Dentistry. Cheat sheet: briefly, the most important

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Dentistry. Cheat sheet: briefly, the most important

Lecture notes, cheat sheets

Directory / Lecture notes, cheat sheets

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Table of contents

Dentistry as a science
Anatomical structure of the maxillofacial region
The structure of the teeth
Innervation of the maxillofacial region
Caries
Pulpitis
Periodontitis
Complications of periodontitis. Radicular cysts of the jaw
Equipment and equipment of the dental office
Anomalies in the size, shape and number of teeth
Anomalies in the position of the teeth
Anomalies of bite and anomalies of the dentition
Increased tooth wear
Etiology of increased tooth wear
Clinical manifestations of increased tooth wear
Treatment of increased tooth wear
Two-stage orthopedic treatment of increased tooth wear
Periodontitis
Chronic focal oral infection
Diseases of the oral mucosa
Catarrhal stomatitis and ulcerative stomatitis
Acute aphthous stomatitis and leukoplakia
Chronic recurrent aphthous stomatitis (CRAS)
Changes that occur on the oral mucosa in various diseases
Acute mechanical injury of the oral mucosa
Chronic mechanical trauma (CMT) of the oral mucosa
Chemical damage to the oral mucosa, types of anesthesia
Chronic chemical injury (CCT) of the oral mucosa
Diagnosis of the state of the human body by language
collagenoses
Trigeminal nerve diseases
Periomandibular abscesses and phlegmon
Phlegmon of the submandibular region
Phlegmon of the buccal region, posterior-mandibular, pterygo-mandibular and parapharyngeal spaces
Phlegmon of the floor of the mouth
Etiology, pathogenesis and pathological anatomy of osteomyelitis
Clinic and diagnosis of acute odontogenic osteomyelitis
Treatment of osteomyelitis
Modern filling materials
Composite materials. Definition, development history
Classification of composite materials
Macrofilled composite materials
Microfilled and hybrid composites
Composite properties
Mechanism of adhesion of composites to dentin
Polymerization of composites
Requirements for working with composite material
Adhesion mechanism between composite layers
Polycarboxylate cements
Glass ionomer cements
Gasket cements
Compomers
The method of working with composite materials of chemical curing (on the example of the microfilament composite "Degufil")
Method of application of light-cured composite material
Principles of biomimetic construction of teeth with restorative materials

1. Dentistry as a science

Dentistry is a relatively young discipline in medicine: as a separate branch, it was formed only in the 20s. XNUMXth century Its name comes from two Greek roots "stoma" - mouth, hole and "logos" - teaching and literally means "science of the organs of the oral cavity." In the modern sense, dentistry is defined as a field of clinical medicine that deals with the study of diseases of the teeth, oral mucosa, jaws, face and part of the neck, and which develops methods for their diagnosis, treatment and prevention.

The prototype of modern dentistry in antiquity was dentistry, which at that time did not belong to traditional official medicine, and maxillofacial surgery, which was considered a branch of general surgery. The representatives of dentistry were mainly hairdressers and artisans, and sometimes simply self-taught. The first book on dentistry in Russia "Dentistry, or dental art about the treatment of diseases, with the application of children's hygiene" was written and published in 1829 by the head physician of the St. Petersburg Medical and Surgical Academy (today the St. Petersburg Military Medical Academy) Alexei Sobolev. But, despite this, the development of dentistry in Russia was very slow; the first dental school was founded only in 1881 by the works of N. V. Sklifosovsky, A. A. Limberg and N. N. Znamensky. The first society of dentists in Russia was organized in 1883.

In the late nineteenth - early twentieth centuries. dental care was mainly provided in private paid medical institutions, their services were available only to a small circle of the public, which also did not contribute to the rapid development of dentistry. Only after the First World War and then the October Revolution, with a change in the social way of life of the country, conditions appeared for the rapid development of the practical and scientific foundations of this area of medicine. With the expansion and strengthening of the theoretical base and the accumulated experience, the prerequisites for the merging of dentistry and maxillofacial surgery into a single discipline appeared based on the similarity of pathological processes and approaches to treatment. A. A. Limberg, A. I. Evdokimov, G. A. Vasiliev, I. G. Lukomsky, A. E. Rauer, F. M. Khitrov, D. A. Entin, N. M. Mikhelson, M. V. Mukhin.

Later, with the development of a new discipline, independent sections were formed in it: therapeutic dentistry, surgical, pediatric and orthopedic.

2. Anatomical structure of the maxillofacial region

Oral cavity It is represented by the following organs and anatomical formations: the oral fissure, the vestibule of the oral cavity, cheeks, lips, hard palate, soft palate, tongue, gums, teeth, upper and lower jaws.

oral fissure limited lips, forming the corners of the mouth from the sides. The thickness of the lips is represented by the circular muscle of the mouth and subcutaneous fat. thick cheeks make up adipose tissue (Bish's lump) and buccal muscle bundles. On the inner surface of the cheeks in the projection of the crown of the upper second large molar, there is a papillary eminence of the mucous membrane, on the top of which or under it in the vestibule of the oral cavity, the excretory duct of the parotid salivary gland opens. vestibule of the oral cavity formed in front - by the oral fissure (or closed lips) and cheeks on the sides, behind - by the upper and lower gums and teeth. Gums - the alveolar processes of the upper jaws and the alveolar part of the lower jaw, covered with a mucous membrane, they cover teeth in the neck area. Paired parotid, sublingual and submandibular, as well as many small glands of the oral mucosa secrete saliva (up to 1,5 liters per day). Thanks to it, the mucous membrane and enamel of the teeth are constantly moistened. Solid sky formed by the palatine processes of the upper jaws, perpendicular processes of the palatine bones. Soft sky represented by muscle fibers covered with a mucous membrane with a large number of mucous glands; arches depart from it on the sides - palatoglossal and palatine-pharyngeal, between which there are accumulations of lymphoid tissue (palatine tonsil). Language - a muscular organ covered with a mucous membrane. In its structure, a root, a wider back, a body, a middle part and an apex are distinguished. In the rough mucous membrane of the tongue, four types of papillae containing taste buds are distinguished: filiform, leaf-shaped, mushroom-shaped, rough.

The upper jaw is a paired immovable bone. In its structure, the body, the palatine process, which takes part in the formation of the hard palate, the frontal process, which participates in the formation of the orbit, the zygomatic process (connects to the zygomatic bone), the alveolar process, which carries the holes of the teeth - alveoli, are distinguished. In the body of the upper jaw there is a cavity called the maxillary sinus, which contains air and is lined from the inside with a mucous membrane. In the immediate vicinity of it are the tops of the roots of large molars (especially the sixth), which creates conditions for the transition of the inflammatory process from the tooth and nearby tissues to the sinus and the development of sinusitis. The lower jaw is an unpaired movable bone that has the shape of a horseshoe. In its structure, a body is isolated, containing dental alveoli on the upper edge, two branches ending in the condylar and coronoid processes; the condylar process, connecting with the articular fossa of the temporal bone, participates in the formation of the temporomandibular joint.

3. The structure of the teeth

In the structure of temporary and permanent teeth, the following formations are distinguished:

1) crown - part of the tooth protruding above the gingival margin into the oral cavity. In turn, a tooth cavity is isolated in the crown, which, when narrowed, passes into the root canal of the tooth, the pulp is a loose tissue that fills the tooth cavity and contains a large number of vessels and nerves;

2) neck - part of the tooth that separates its root from the crown and is located under the gingival margin;

3) root - part of the tooth, immersed in the alveolus of the jaw, it passes through the canal of the root of the tooth, ending with a hole; the main purpose of the root is to tightly fix the tooth in the alveolus with the help of a powerful ligamentous apparatus, represented by strong connective tissue fibers that connect the neck and root with a plate of compact bone substance of the alveolus.

The ligamentous apparatus of the tooth, together with the blood and lymph vessels supplying it, the nerves, is called the periodontium. It provides a tight fixation of the tooth, and due to loose fiber and interstitial fluid between the fibers, it also provides cushioning.

In the histological structure of the tooth, the following layers are distinguished:

1) enamel - the hardest tissue of the human body, close in strength to diamond, it covers the crown and neck of the tooth, its thickest layer is located above the tubercles of the tooth crown, towards the cervical region its thickness decreases. The strength of enamel is due to the high degree of its mineralization;

2) dentin - the second strongest tissue, which makes up the bulk of the tissues of the tooth, consisting of collagen fibers and a large amount of mineral salts (70% of the mass of dentin is lime phosphate); in the outer layer of the main substance of dentin, collagen fibers are arranged radially, and in the inner (near-pulpal) - tangentially. In the peripulpal dentin, in turn, predentin is isolated - the most deeply located layer of constant growth of the dentin layer;

3) cement covers the root of the tooth, is similar in structure to bone tissue, incorporates collagen fibers and a large number of inorganic compounds;

4) pulp It is represented by loose fibrous connective tissue with a large number of nerves and blood vessels, which are branches of the corresponding arteries and nerves of the jaws, as well as lymphatic vessels. Nerves and arteries in the form of a neurovascular bundle penetrate into the tooth cavity through the opening of the root canal. The pulp performs various functions: trophic, regenerative (due to the supply of cambial elements), manifested in the formation of new replacement dentin during the carious process, and protective.

4. Innervation of the maxillofacial region

The maxillofacial region is innervated by the following nerves:

1) trigeminal (V pair of cranial nerves), which performs, in addition to sensory innervation, also motor (for masticatory muscles) and departs from the trigeminal node as part of three branches: ophthalmic, maxillary and mandibular nerves;

2) facial (VII pair of cranial nerves), which carries out motor and autonomic (for the sublingual and submandibular salivary glands) regulation, in its course it gives off branches of the temporal, zygomatic, buccal, mandibular marginal and cervical.

The high regenerative abilities of the tissues of the maxillofacial region are due to a rather abundant blood supply, mainly due to the external carotid artery, which branches into the lingual, facial, maxillary and superficial temporal.

The lymphatic network of the maxillofacial region is quite well developed and provides good lymph drainage. All lymph nodes of this zone are divided into lymph nodes of the face, submandibular region and neck. From the region of the tubercle of the upper jaw and the maxillary sinus, the lymph is directed to the deep cervical lymph nodes, which are usually not possible to palpate. On the way of outflow of lymph from the teeth, the first barrier is represented by the submandibular and submental nodes. From the tissues of the maxillofacial region, lymph through the lymphatic vessels of the neck enters the jugular lymphatic trunks.

The laying of the dentition occurs in humans at the 6-7th week of intrauterine development from the ectodermal and mesodermal sheets. At 6-7 months of age, the eruption of temporary, or milk, teeth begins, which is completed by 2,5-3 years. The anatomical formula of the teeth of the temporary bite looks like: 212, i.e. on each side of the upper and lower jaws there are two incisors, one canine and two molars; the total number of temporary teeth is 20. At the age of 5-6 years, the eruption of permanent teeth, or molars, begins, which by the age of 12-13 completely replace milk teeth; however, this process is completed only by the age of 22-24 with the appearance of the third large molars ("wisdom teeth"), and sometimes later. There are 32 teeth in the permanent bite, their anatomical formula looks like: 2123, i.e. two incisors, a canine, two premolars and three molars on each side on the upper and lower jaws. The oral cavity together with the dentition performs various functions in the human body, such as:

1) mechanical processing of food;

2) chemical processing of food;

3) the function of sound production;

4) respiratory function;

5) sensitive (analyzer) function.

5. Caries

Currently, there are a huge number of theories of the occurrence of caries. One of them boils down to the fact that if oral hygiene is not observed, plaque appears, which is localized on the lateral surfaces of the teeth, fissures, in other words, in those places where it is not removed during chewing and is firmly associated with the surface of the teeth. The composition of plaque consists mainly of polysaccharides, mineral salts, which contribute to its compaction. In practical dentistry, such a formation is called "dental plaque", which, along with the above components, includes microorganisms, mainly represented by streptococci. Bacteria, in turn, produce lactic acid, which demineralizes the enamel and becomes the beginning of a carious process. There is no doubt that the resistance of teeth to caries is associated with the body's natural defenses. It is noticed that in persons with a weakened resistance, soft plaque is more actively formed. According to another theory, it is believed that the frequency of occurrence of carious lesions is determined not only by the state of the body, but also by the properties and qualitative composition of saliva. In persons who are prone to caries, saliva is more viscous, the content of mineral salts in it is changed. In the occurrence of caries, the presence of carbohydrates in saliva and the permeability of tooth enamel play a certain role.

carious spot (macula cariosa) - a whitish spot, which is represented by an area of enamel turbidity and weaker light refraction. There are no signs of enamel destruction. When probing this area, the enamel defect is not detected. The likely outcome of this stage is the transition to the next stage of superficial caries (caries superficialis). This stage is characterized by the appearance of roughness and pigmentation at the site of the chalky spot. In addition, it is possible to identify areas of softening of the enamel. This stage ends when the process extends to the entire thickness of the enamel. Medium caries (caries media) is characterized by the presence of a carious cavity, which is located in the dentin layer at a shallow depth. A condition in which a carious cavity of considerable size is formed is called deep caries (caries profunda).

clinical picture very clear: the absence of spontaneous pain, episodic pain attacks, which is due to thermal and chemical factors. After elimination of these irritants, the pain disappears. The appearance of pain with mechanical pressure indicates deep caries.

RџSЂRё treatment caries, it is first necessary to remove the affected areas of dentin and enamel by mechanical treatment with a bur and a drill. After that, the resulting cavity, which is larger than the original carious cavity, is filled with filling material. Treatment of superficial and medium caries is performed in one session, deep - in 2-3 sessions.

6. Pulpitis

As the carious process spreads to deeper layers of dentin, there comes a time when a thin layer of infected dentin remains between the bottom of the carious cavity and the cavity of the tooth. The ability of microorganisms to penetrate through the dentinal tubules into the layers of dentin that have not yet been destroyed causes infection of the pulp long before the first signs of communication between the carious cavity and the tooth cavity appear.

Acute pulpitis. There is a direct relationship between the severity of the development of inflammation of the dental pulp and the virulence of microorganisms. In acute pulpitis, exudate compresses the nerve endings, which, in turn, leads to pain.

Clinic characterized by the appearance of acute spontaneous and paroxysmal pain. Often, patients cannot accurately indicate the location of the tooth, since the pain is diffuse in nature due to its irradiation along the branches of the trigeminal nerve. The paroxysmal pain is due to the blood filling of the vessels.

In the clinic, several types of pulpitis are distinguished: acute serous-purulent focal and acute purulent diffuse pulpitis. In the case of serous-purulent pulpitis, the pain is aggravated by cold water, and with purulent pulpitis it temporarily subsides.

Thanks to pyogenic bacteria, the serous inflammatory process quickly progresses to a purulent one, which ultimately leads to gangrene of the pulp. In turn, purulent pulpitis is accompanied by increased pain.

RџSЂRё treatment pulpitis to relieve pain, analgesics are used, but this measure is not always effective.

Chronic pulpitis. This disease proceeds much more slowly than acute pulpitis. It may be accompanied by intermittent aching pains. In some situations, any pathological sensations may be absent, which is explained from the pathological and anatomical point of view. The dead tissue is replaced by granulations. Sometimes these granulations can protrude into the cavity of the tooth - a tooth polyp.

Treatment is to eliminate the inflammatory process and prevent its spread, relieve pain. The classic method of treatment is the use of arsenic paste, which is applied to the bottom of the carious cavity. Arsenic is a protoplasmic poison that causes necrosis and mummification of the pulp and its elements.

After mechanical amputation of the pulp, the next stage is started, which consists in drug treatment, followed by filling the root canal with liquid cement, and the tooth cavity is filled with filling material. It should be added that the treatment of pulpitis can be carried out with the help of a local anesthetic, which greatly simplifies the procedure, since arsenic paste is not used in this case.

7. Periodontitis

Microorganisms can cause inflammation in periodontal - the ligamentous apparatus of the tooth, and are also able to penetrate there in different ways, including hematogenous.

Allocate acute serous periodontitis and acute purulent periodontitis. In the first case, the clinic will be characterized by aching pains with a clear localization, a feeling of elongation of the affected tooth. In acute purulent periodontitis, local and general changes will be observed. The pain intensifies, takes on a pulsating character with rare light intervals. Often there is irradiation of pain along the branches of the trigeminal nerve. Even a light touch can cause severe pain. The tooth becomes mobile as a result of melting of the ligamentous apparatus.

During treatment, it is first necessary to ensure the outflow of exudate by creating drainage through the carious cavity. To do this, the gangrenous pulp is removed with an extractor.

Chronic periodontitis. As a rule, it proceeds in an asymptomatic form. There are the following types: fibrous, granulating, granulomatous chronic periodontitis. With fibrous periodontitis, there is practically no pain, the pulp is replaced by coarse fibrous connective tissue. Downstream, this type of periodontitis is sluggish. On the radiograph, it looks like a narrow uniform strip, limited by the contours of the tooth root and the line of the plate of the compact substance of the alveolus. In this case, deformation in the form of periodontal thickening is observed at the top of the tooth root. With granulating periodontitis, granulation tissue is formed in the periodontium. There is a destruction of the cortical plate in the alveolus. Unlike fibrous periodontitis, in this case, the plate of the compact bone substance of the alveolus is destroyed. This form of periodontitis is the most active, since, in addition, it is accompanied by destruction of the periodontal gap and infiltrative growth of granulations. In some cases, fistulas can form, which can break through to the skin of the face in the perimaxillary region. When examined by a dentist, hyperemia and swelling are found at the root of the diseased tooth, and the presence of a fistulous passage facilitates the correct diagnosis. With granulomatous periodontitis, a connective tissue membrane is formed in the form of a sac attached to the top of the tooth root. This formation is called a granuloma. Due to the constant increase in the size of the granuloma, there is an increase in pressure on the surrounding tissue, which, in turn, leads to the melting and displacement of the bone elements of the alveoli.

The only possible option treatment This pathology is a surgical intervention, which is aimed at removing pathological tissue from the peridental focus of inflammation.

8. Complications of periodontitis. Radicular cysts of the jaw

The following complications are distinguished: local and general. Common complications include the phenomena of intoxication as a result of the absorption of waste products of microorganisms from the focus of inflammation. Dissemination of bacteria to various organs, which, in turn, can lead to secondary diseases. Local complications include such as fistulous tracts and cysts. Let us consider in more detail several nosological units.

Odontogenic fistulas. They are formed as a result of the penetration of granulation tissue into the thickness of the alveolar process, under the periosteum, and then under the mucosa. As a result, a fistulous passage is formed at the level of the projection of the apex of the tooth root.

To confirm the diagnosis chronic periodontitis, it is necessary to conduct a thorough diagnosis with the maximum detail of diagnostic techniques. One of the main methods is the radiography of the diseased tooth, as well as the palpation determination of the granulation cord extending from the alveolar process into the soft tissues.

Treatment aimed at sanitation of the source of infection (diseased tooth). At the same time, in some cases, the fistulous course is tightened independently, otherwise curettage of granulations is performed. If the diseased tooth is not amenable to conservative treatment, resection of the apex of the tooth root or replantation is performed. In order to avoid recurrence of the fistula, the granulation cord is transected, for which a 2-3 cm long incision is made, then the compact plate of the alveolar process and the exit site of the granulation cord from the bone are exposed. This cord is crossed, then the wound is plugged with gauze with iodoform for 3-4 days.

Radicular cysts of the jaw - These are formations of a tumor-like form that occur as a result of an inflammatory process in the periodontium of the tooth. This disease is a consequence of a chronic inflammatory process, which involves the remnants of the embryonic epithelium, which, in turn, forms the inner layer of the cyst membrane.

The clinic of this disease has an erased character, so the absence of pain can often lead to the destruction of the jaw, as in the previous case. Diagnosis of this disease, as in the previous case, is based mainly on X-ray data. This type of cyst is visualized as a clearly defined rarefaction of the bone tissue of a round or oval shape. In addition, there are such generally accepted research methods as palpation, with which you can determine the protrusion of the lower jaw.

Treatment is only surgical, in which partial excision of the cyst membrane or complete removal of the membrane is performed. Before proceeding with this operation, the issue of preserving the tooth that caused this pathological process, as well as the neighboring teeth, the roots of which may be involved in the pathological process, is resolved.

9. Equipment and equipment of the dental office

In polyclinics and dental departments, it is desirable to allocate an initial examination room, a functional diagnostics room, an amalgam preparation room, a room for washing and sterilizing instruments, and a physiotherapy service room.

To organize one workplace in the dental office, if possible, a spacious room with good natural light should be allocated: its area should be about 15 m² (approximately 4,4 x 3,5 m). The height of the ceilings in the office should be at least 3,3 m.

In daily activities, when providing qualified assistance, the dentist uses special equipment. It includes:

1) dental chair for the patient;

2) electric or turbine drill;

3) dental unit;

4) a chair for a doctor.

The dental chair is designed for comfortable positioning of the patient, fixing him in a sitting or lying position, facilitating the doctor's access to the surgical field, eliminating the patient's discomfort and tension.

With the help of a drill, a dentist performs the main event in the clinic of therapeutic dentistry, namely, the preparation of hard dental tissues.

The dental unit is designed to provide assistance in stationary conditions. It is equipped with an electric motor, a lamp, a saliva ejector, a diathermocoagulator, an apparatus for electrodiagnostics, a water system unit, guns for water and air. In the clinical practice of examination, treatment of teeth and oral mucosa, the dentist uses a special set of tools. The main ones are:

1) dental mirror. With its help, areas of the oral cavity that are inaccessible to direct vision are examined, cheeks, tongue, lips are fixed, and they are also protected from injury while working with sharp instruments. Dental mirrors are of two types - flat, giving a true reflection of the object in question, and concave, increasing it;

2) dental probe. Depending on the shape, it can be angular or straight, sharp or blunt;

3) dental tweezersused to hold and transfer cotton swabs into the oral cavity to isolate the tooth from saliva;

4) trowels. With the help of a trowel (spatulas of a straight or curved shape), medicinal substances are introduced into the carious cavity of the tooth;

5) dental hookshaving the form of a straight or curved spatula with pointed ribs;

6) excavator, which is a pen with sharp spoons on both sides.

10. Anomalies in the size, shape and number of teeth

giant teeth - These are teeth with very large, incongruous crowns. This pathology occurs most often with permanent occlusion and somewhat less frequently with milk. Usually, the incisors of the upper or lower jaw are affected, but other teeth can also be affected. The treatment for this defect consists in the removal of giant or adjacent teeth. In the event that after the removal of these teeth and correcting the position of the rest, gaps remain between the teeth, they resort to prosthetics and close the corresponding defects.

Often there is also a directly opposite anomaly of magnitude - small teeth. These are teeth that have the correct shape, but disproportionately small crowns. Such a defect is mainly found in permanent occlusion, most often the incisors are affected, especially the upper and lateral ones. Small teeth, as a rule, are separated by large gaps and distort the harmony of the face with their appearance. To correct this defect, such teeth are covered with plastic crowns or they are removed with subsequent prosthetics.

Anomalies in the shape of the teeth

ugly teeth - teeth that have a diverse, irregular shape, more often this defect is observed on the upper jaw in its frontal area. The treatment is to correct the shape of the malformed tooth by prosthetics or to remove it.

spiked teeth - These are teeth that have crowns, pointed in the form of a spike. These can be the lateral teeth of both jaws, the central and lateral incisors also often suffer. Treatment of such defects consists in prosthetics; often spiked teeth are removed and subsequently replaced with various prostheses, which can be both removable and fixed.

Anomalies in the number of teeth

One of the most common examples of these anomalies is adentia - congenital absence of teeth and their rudiments. There are two forms of adentia: partial and complete. Treatment - prosthetics, which may be preceded by a course of orthodontic treatment.

Supernumerary teeth - excessive number of teeth. They are located most often in the region of the anterior teeth and are often spike-shaped, but may resemble adjacent teeth. In determining the treatment tactics, the location of the extra tooth and its effect on the position of complete teeth are taken into account. In case of displacement of adjacent teeth, supernumerary teeth are removed and appropriate orthodontic treatment is carried out. However, it is also possible to save a supernumerary tooth if it is located in the arch and does not adversely affect the adjacent teeth, while the shape of the crown can be corrected by prosthetics.

11. Anomalies in the position of the teeth

Vestibular deviation is the displacement of the teeth outward from the dentition, such a deviation may affect one or even several teeth of the upper or lower jaw. In the treatment of this pathology, the teeth that are located vestibularly are moved in the palatal direction.

With a high or low arrangement of teeth, they are shifted in the vertical direction. In the upper jaw, supraocclusion is a high position of the tooth, while its tip does not reach the plane in which the dentitions close; infraocclusion - low position of the tooth. Treatment: the tooth and the area of the alveolar process adjacent to it are subjected to traction, for this purpose traction devices are used.

Mesiodistal displacement of teeth is understood as their incorrect location in front of the normal position in the dental arch or behind. The anterior and posterior teeth can be displaced equally. The main principle of treatment is the movement, restoration and fixation of teeth in the correct position, which is achieved by using removable and non-removable orthodontic appliances.

Oral tilt - an incorrect position of the teeth, in which there is a displacement of the teeth inward from the dental arch, in the palatal direction or towards the tongue. Usually, when tilted, the root of the tooth is located in the alveolar process, and only its crown is deviated to the side, with corpus dystopia, the tooth is completely displaced outside the dentition. An acceptable method of treatment is the separation of the bite and the movement of the teeth in the vestibular direction.

Diastema - a wide gap separating the central incisors is observed mainly in the upper jaw. Various factors can contribute to the development of a diastema. Treatment can be only orthodontic or complex, including surgical intervention followed by hardware convergence of the incisors.

Tooth rotation - an incorrect position in which the tooth is in its normal place, but is rotated while causing cosmetic and functional defects. Most often, the incisors of the upper and lower jaws are subjected to deformation. Treatment for this disorder consists in turning the tooth in the right direction, giving it the correct position and further fixing.

Transposition of teeth - permutation of teeth in the dentition.

Crowded arrangement of teeth. With this anomaly, the teeth are located very closely, while they stand in a position rotated along the axis and lean on each other.

Trems - gaps between teeth. There are physiological and pathological tremas. Physiological arise as a result of the growth of the jaws and relate to the features of the milk bite. Pathological tremas are observed after the replacement of milk teeth with molars with concomitant occlusion pathology.

12. Anomalies of bite and anomalies of the dentition

This violation is caused by narrowing of the alveolar processes of the jaws or expansion in various places and is expressed by crowding of teeth, vestibular or oral teething, partial adentia, their rotation along the axis, the presence of supernumerary teeth, diastemas. There are many forms of narrowed dentition, here are the most common:

1) acute-angled shape;

2) common form;

3) saddle shape;

4) V-shape;

5) trapezoidal shape;

6) asymmetrical shape.

The main causes of deformation of the dental arches are the underdevelopment of the jaws caused by diseases of early childhood. The basis of treatment is the expansion and contraction of the dental arches and the correct placement of the teeth.

Bite anomalies

Bite anomalies are deviations in the relationship between the dentition of the upper and lower jaws. The following deviations are distinguished.

Sagittal deviations

Prognathia (distal occlusion) - discrepancy between the dentition, characterized by the protrusion of the upper teeth or distal displacement of the lower jaw. Prognathia can be partial or total.

Progenia (medial bite) is a discrepancy between the dentition due to the protrusion of the lower teeth or the medial displacement of the lower jaw. It can be partial or complete. The reasons may be a congenital feature of the structure of the facial skeleton, improper artificial feeding, etc. Treatment is achieved by correcting the oral inclination of the upper incisors.

Transversal deviations

These include the narrowing of the dentition, the discrepancy between the width of the upper and lower dentition. vertical deviations.

Deep bite - closing of the dentition, while the front teeth overlap with antagonists. There are two types of bite - vertical and horizontal. Treatment consists in uncoupling the bite, expanding the dentition on the lagging jaw.

Open bite - the presence of a gap between the teeth. This gap is more common in the region of the anterior teeth.

A crossbite is a reverse closure of the teeth of the right or left half of the bite.

13. Increased tooth wear

This is a natural process of erasing the upper layer of the tooth throughout life, which is observed in the horizontal and vertical planes. Erasure in the horizontal plane is observed on the tubercles of the canines, along the cutting edge of the incisors, on the chewing surface of premolars and molars. The associated decrease in the height of the crowns of the teeth should be considered as an adaptive reaction of the organism. The fact is that with age, the vascular system and other periodontal and temporomandibular joint tissues change. By vertical abrasion is meant, in particular, the abrasion of the contact surfaces of the tooth, whereby the interproximal contact parts are converted into contact areas over time. Disappearance of contacts between the teeth usually does not occur due to the medial displacement of the teeth. It is known that with age there is a settling (retraction) of the gums and interdental papilla. This should have resulted in the formation of triangular spaces between the teeth. However, their occurrence is prevented by the appearance of the contact area. In some people, natural functional wear is slow or absent. This could be explained by the use of soft food, a deep bite that makes lateral movements of the lower jaw difficult, and weakness of the masticatory muscles.

However, there are patients who have a normal bite, and they eat a wide variety of foods, and the abrasion is so weakly expressed that with age, the tubercles of the molars and premolars remain almost unchanged. The reasons for this are unknown. Often such patients suffer from periodontitis.

In addition to natural, there is also increased abrasion. It is characterized by a rapid course and significant loss of enamel and dentin. Increased tooth wear occurs in 4% of people aged 25 to 30 years and in 35% - up to 40-50 years (V. A. Alekseev). Increased abrasion violates the anatomical shape of the teeth: the tubercles and cutting edges of the incisors disappear, while the height of the crowns decreases. With a direct bite, the cutting edges and the chewing surface of all teeth are abraded, and with a deep bite, the surfaces of the lower teeth are abraded.

There are three degrees of abrasion. At the first degree, the tubercles and cutting edges of the teeth are erased, the second degree is characterized by the erasure of the crown of the contact pads, at the third - to the gums. In this case, not only enamel and dentin, but also secondary (replacement) dentin are subjected to abrasion. In response to abrasion, a protective reaction develops from the side of the tooth pulp. It is expressed in the deposition of secondary dentin, which deforms the tooth cavity, and sometimes causes its complete infection. With degeneration of the pulp, the deposition of replacement dentin may not keep pace with the loss of tooth tissue. As a result, the death of pulp tissue may occur without perforation of its cavity.

14. Etiology of increased tooth wear

Enamel abrasion may be accompanied by increased sensitivity to thermal and chemical irritants.

With the preservation of the plastic properties of the pulp, hyperesthesia can quickly disappear, since a layer of dentin is formed.

With increased abrasion, periapical foci of inflammation are sometimes found.

Increased abrasion of teeth is polyetiological. The causes of the pathological process may be the following.

1. Functional insufficiency of hard tissues of teeth, due to their morphological inferiority:

1) hereditary (Stenson-Capdepon syndrome);

2) congenital;

3) acquired (a consequence of neurodystrophic processes, dysfunctions of the circulatory system and endocrine apparatus, metabolic disorders of various etiologies.

2. Functional overload of teeth with:

1) partial loss of teeth (with a decrease in the number of antagonistic pairs of teeth, mixed function, etc.);

2) parafunctions (bruxism, foodless chewing, etc.);

3) hypertonicity of the masticatory muscles of central origin and hypertonicity associated with the profession (vibration, physical stress);

4) chronic trauma of the teeth.

Occupational hazards: acid and alkaline necrosis, dustiness, hydrochloric acid intake for achilles. Some of the listed reasons can cause generalized abrasion, and some can only cause local damage.

Obviously, the term "increased abrasion" combines various conditions of the dental system, the causes of which often remain unclear, but the pathological and anatomical characteristic is common to all: the rapid loss of enamel and dentin substance of all, perhaps only part of the teeth.

Increased abrasion captures various surfaces of the teeth: chewing, palatine, labial and cutting edges. According to the localization of the defect, three forms of increased abrasion are distinguished: vertical, horizontal and mixed. With a vertical form, increased abrasion in patients with normal overlap of the anterior teeth is observed on the palatal surface of the upper anterior and labial surfaces of the lower teeth of the same name. The horizontal form is characterized by a decrease in hard tissues in the horizontal plane, as a result of which horizontal abrasion facets appear on the chewing or cutting surface. Horizontal increased abrasion most often captures both the upper and lower dentition. There are patients with intensely pronounced abrasion of tooth tissues, observed only in the upper jaw, with normal abrasion of teeth in the lower jaw. With a mixed form, abrasion can develop both in the vertical plane and in the horizontal.

15. Clinical manifestations of increased tooth wear

The tendency to increased abrasion is limited and spilled. Limited or localized increased abrasion captures only individual teeth or groups of teeth, without spreading along the entire arch. Usually, the anterior teeth are affected, but premolars and molars can also be involved in the destructive process. With a generalized (diffuse) form, increased abrasion is noted throughout the entire dental arch.

Depending on the compensatory-adaptive reaction of the dentition, the increased abrasion of dental tissues is divided into the following clinical variants: uncompensated, compensated and subcompensated. These options are both with generalized abrasion and with localized. Localized uncompensated increased abrasion is characterized by a decrease in the size of the crowns of individual teeth and the subsequent appearance of a gap between them (open bite). The interalveolar height and shape of the face are preserved due to the presence of worn teeth. Localized compensated abrasion causes shortening of the crowns of individual teeth, worn teeth, while in contact with antagonists due to hypertrophy of the alveolar part (vacant hypertrophy) in this zone, which leads to dentoalveolar elongation. The interalveolar height and face height remain unchanged. Generalized uncompensated increased abrasion of hard dental tissues inevitably leads to a decrease in the height of the crowns of the teeth, which is accompanied by a decrease in the interalveolar height and face height. The lower jaw approaches the upper, its distal displacement is possible. The facial skeleton in patients with this form of abrasion, according to X-ray cephalometric analysis (V. M. Shulkov), is characterized by:

1) a decrease in the vertical dimensions of all teeth;

2) deformation of the occlusal surface;

3) a decrease in the depth of incisal overlap and sagittal inter-incisal distance;

4) decrease in interalveolar height;

5) dentoalveolar reduction in the region of the upper canines and first premolars.

Generalized compensated increased abrasion of dental tissues is expressed in a reduction in the vertical dimensions of the crowns of all teeth, a decrease in the interalveolar height, and the height of the lower third of the face does not change. The decrease in crowns is compensated by the growth of the alveolar process.

A generalized subcompensated form of increased tooth wear is a consequence of insufficiently pronounced dentoalveolar elongation, which does not fully compensate for the loss of hard tooth tissues, which contributes to a decrease in the vertical dimensions of the lower third of the face and the approach of the lower jaw. Increased abrasion can be combined with the loss of part of the teeth, pathology of the masticatory muscles and temporomandibular joints. The clinical picture becomes even more complex.

16. Treatment of increased tooth wear

Therapy for patients with increased tooth wear should include:

1) elimination of the cause;

2) replacement of loss of hard tissues of teeth by orthopedic methods.

Prosthetics with increased abrasion of teeth provides for both therapeutic and prophylactic purposes. The former means improving the function of chewing and the appearance of the patient, the latter - preventing further erasure of hard tissues of the tooth and preventing diseases of the temporomandibular joints.

The treatment of patients is:

1) restoration of the anatomical shape and size of the teeth;

2) restoration of the occlusal surface of the dentition;

3) restoration of interalveolar height and height of the lower third of the face;

4) normalization of the position of the lower jaw. After defining the tasks, the means for their implementation are selected. These include various types of artificial crowns, inlays and removable dentures with occlusal linings.

Therapy of patients with generalized uncompensated abrasion in the early stages is prophylactic and consists of prosthetics with counter crowns or inlays. Crater-shaped cavities are filled with composite materials.

With increased abrasion of the II degree, prosthetics are carried out with artificial crowns (cermet, metal-plastic, porcelain) or removable dentures with cast occlusal platforms. Restoration of the shape of the tooth at the III degree of abrasion is carried out using stump crowns, since root canals with increased abrasion are often obliterated and the treatment of such teeth is difficult. In this case, the stump is fixed on parapulpal pins.

Restoring the occlusal surface of worn dentition is a difficult task, it is carried out by various methods. One of them is recording the movements of the lower jaw using a pantograph and further modeling of fixed prostheses or occlusal linings in an individual articulator.

The second method consists in modeling bridges and crowns on individual occlusal surfaces obtained using intraoral recording of the movement of the lower jaw on hard wax bite ridges. Wax occlusal rollers are applied to the upper and lower dentition along the width of the corresponding teeth 2 mm above the expected height of the crowns. Further, the required interalveolar height is determined and a prosthetic plane is built. The next step is the rubbing of the rollers with various movements made by the lower jaw. In the occluder, modeling and selection of artificial crowns are carried out.

17. Two-stage orthopedic treatment of increased tooth wear

Initially, temporary plastic crowns and bridges are made, and patients use them for a month. During this period, the formation of occlusal surfaces of temporary prostheses takes place. At the second stage, temporary prostheses are replaced by permanent ones. To do this, impressions are taken from temporary prostheses, models are cast, then they are crimped in a thermal vacuum apparatus using polystyrene. In the oral cavity, after the removal of temporary prostheses, impressions are obtained and collapsible models are created. Teeth prints in polystyrene are filled with melted wax and a template is applied to the model. After the wax has hardened, the polystyrene templates are removed, leaving a wax impression of an individually shaped chewing surface on the model.

Restoration of the height of the lower third of the face and the position of the lower jaw in patients with uncompensated generalized increased abrasion is performed simultaneously or gradually. At the same time, the interalveolar height can be increased within 4-6 mm in the region of the lateral teeth in the absence of a disease of the temporomandibular joint and masticatory muscles. It is obligatory to maintain a free interocclusal distance of at least 2 mm. The change in the position of the lower jaw is carried out simultaneously by prosthetics or on a medical device with an inclined plane, followed by prosthetics. Simultaneous movement of the lower jaw is indicated for patients in whom erasure developed quickly, who developed the habit of holding it in an advanced position. Treatment and restoration of the form from an anatomical point of view of the function of the teeth and the appearance of patients without changing the interalveolar height. With grade I abrasion, the treatment is prophylactic and consists in creating a three-point contact on opposite crowns or inlays without changing the interalveolar height. With grade II wear, it becomes necessary to restore the anatomical shape of the teeth without a significant increase in the height of the lower third of the face, since the latter is not changed. When erasing teeth of the XNUMXst degree, orthopedic treatment is carried out in several ways. In some patients, in order to carry out the restructuring of the alveolar parts, followed by prosthetics with stump crowns, special training is carried out. In other patients, a special preparation of the oral cavity is carried out: filling the roots of the teeth according to the Elbrecht method and prosthetics with removable dentures. In the third patients, special surgical preparation is carried out, which consists in the extraction of the roots of worn teeth and part of the alveolar ridge. Prosthetics in these patients is staged: immediate and remote. Treatment of patients with localized erasure is carried out according to the principles described above, and depends on the form of erasure.

18. Periodontitis

Periodontitis called a pathological process in which the gums, periodontium, bone tissue, alveoli are involved.

The reason for the development of pathology in the periodontium is a violation of its nutrition. Trophic changes, in turn, are the result of narrowing of the lumen of the supply vessels due to their sclerosis and neurovascular changes in the functional state of the central nervous system.

Violation of the blood supply and nutrition of the periodontium invariably leads to the development and progression of atrophy of the alveolar processes of the upper jaw, as well as the circular ligament and the entire ligamentous apparatus of the tooth. Consider the following reasons for the development of periodontitis:

1) the presence of any local irritant (for example, tartar), which constantly affects the gum, leading to the development of local inflammation;

2) the presence in the oral cavity of specific microorganisms, such as amoeba, dental spirochete;

3) changes in hormonal levels and vitamin deficiency (primarily vitamin C).

Clinical symptoms periodontitis are varied. The main manifestations are symptomatic gingivitis (inflammation of the gums), the formation of pathological gum pockets, the release of pus from the alveoli, atrophy of the alveolar processes. The first sign signaling the occurrence of a pathological process in the periodontal tissues is discomfort, discomfort in the form of itching, burning and paresthesia in the region of the gum margin. Later, swelling and swelling of the gingival papillae joins these symptoms, cyanosis of the gums appears as a result of congestion.

The presence of a focus of chronic inflammation leads to the formation of granulation tissue and its replacement of the ligamentous apparatus of the tooth.

General treatment contributes to the normalization of metabolic processes in the body, replenishing the lack of vitamins (primarily vitamins C and P), increasing the body's reactive abilities, protective and regenerative forces, stabilizing the neuropsychic state: aloe, vitreous, immunomodulators, antihistamines are used, autohemotherapy is performed. Local treatment is designed to normalize the anatomical and physiological state of the periodontium. To do this, sanitation of the oral cavity is carried out, gum pockets are washed with hydrogen peroxide, various antiseptics, teeth with III degree of mobility are removed. Then curettage is performed to remove granulation tissue. In order to create favorable conditions for scarring of the wound surface, magnetic laser therapy and solcoseryl are used. Surgical treatment of periodontitis is carried out under local anesthesia, in order to expose the gingival pocket, the gingival mucosa is dissected and thrown back, granulations, deeply located remnants of tartar and vegetation of the epithelium are removed with a sharp spoon, bur or laser beam.

19. Chronic focal infection of the oral cavity

Chronic infection of the oral cavity has long been a subject of increased interest for physicians as a possible cause of many somatic diseases. For the first time, the idea that a tooth affected by an infectious process as a primary focus can cause secondary lesions of internal organs was expressed by the English scientist D. Genter at the end of the 1910th century. based on long-term clinical observations. A little later, in 2, he was the first to propose the concepts of "focal infection of the oral cavity" and "oral sepsis". Following D. Genter, the American researcher I. Rosenow, in the course of numerous experiments, came to the conclusion that every depulped tooth inevitably becomes the cause of infection of the body. This conclusion led to an unjustified expansion of indications for the extraction of teeth with pulp damage. Domestic dentists have made a significant contribution to the development of ideas about chronic infection of the oral cavity. So, I. G. Lukomsky in his writings showed and then proved in practice that due to the prolonged course of chronic inflammation in the root zone, serious pathophysiological changes occur in its tissues, leading, in turn, to the accumulation of toxins and antigens that change the reactivity of the body and pervert immunological responses to many factors. To date, it is reliably known that all forms of chronic periodontitis and periodontitis with a diverse microflora, sometimes persisting for several years, are sources of chronic inflammation and sensitization of the body, invariably affecting many organs and systems. Odontogenic sources of infection as chronic foci of intoxication are the cause of such diseases as nephritis, endocarditis, myocarditis, iridocyclitis, rheumatism. In this regard, a practicing physician of any specialty should never lose sight of the condition of the patient's oral cavity as a possible cause of the development of the disease or the aggravation of the condition and the occurrence of complications. The danger of these violations due to the need for thorough sanitation of the oral cavity. With the development of chronic periodontitis, various types of conservative treatment are recommended for practically healthy people, while for patients with existing somatic pathology, the affected tooth should be removed to prevent the spread of odontogenic infection throughout the body. Preventive measures to prevent the development of chronic foci of inflammation in the oral cavity are the planned sanitation of the oral cavity for the entire population, regular preventive examinations XNUMX times a year to identify new local foci of infection, the provision of qualified dental care to all patients who are under dispensary observation and undergoing treatment in general medical clinics.

20. Diseases of the oral mucosa

Lesions of the oral mucosa are, as a rule, local in nature and can be manifested by local and general signs (headaches, general weakness, fever, lack of appetite); in most cases, patients turn to the dentist with already pronounced general symptoms. Diseases of the oral mucosa can be primary or be symptoms and consequences of other pathological processes in the body (allergic manifestations, diseases of the blood and gastrointestinal tract, various vitamin deficiencies, hormonal disorders and metabolic disorders). All diseases of the oral mucosa of inflammatory etiology are called the term "stomatitis", if only the mucous membrane of the lips is involved in the process, then they speak of cheilitis, of the tongue - of glossitis, of the gums - of gingivitis, of the palate - of palatinitis.

Despite a large number of publications and various studies of the etiology, pathogenesis and relationship of clinical manifestations of stomatitis, much in their development remains unexplored and unclear. One of the most determining factors in the occurrence of an inflammatory process in the oral mucosa is the presence of a systemic disease that reduces the overall resistance to the action of the bacterial flora; the risk of developing stomatitis increases with existing diseases of the stomach, intestines, liver, cardiovascular system, bone marrow and blood, endocrine glands. Thus, the state of the oral mucosa is often a reflection of the state of the whole organism, and its assessment is an important measure that allows one or another disease to be suspected in time.

As in the case of the etiology of stomatitis, there is still no consensus on their classification. The most common classification proposed by A. I. Rybakov and supplemented by E. V. Borovsky, which is based on the etiological factor; according to this qualification are distinguished:

1) traumatic stomatitis;

2) symptomatic stomatitis;

3) infectious stomatitis;

4) specific stomatitis (lesions that occur with tuberculosis, syphilis, fungal infections, toxic, radiation, drug injuries).

Traumatic, symptomatic and infectious stomatitis can occur both acutely and chronically, depending on the causative agent, the state of the body and the therapeutic measures performed, while specific stomatitis occurs, as a rule, chronically in accordance with the characteristics of the course of diseases, secondary manifestations of which they are.

There is also a classification of stomatitis according to clinical manifestations: catarrhal, ulcerative and aphthous. This classification is more convenient for studying pathological changes and features of individual forms of stomatitis.

21. Catarrhal stomatitis and ulcerative stomatitis

Catarrhal stomatitis is the most common lesion of the oral mucosa; develops mainly in case of non-compliance with hygiene measures, lack of oral care, which leads to the appearance of massive dental deposits and tooth decay. Clinically, catarrhal stomatitis is manifested by severe hyperemia and swelling of the mucous membrane, its infiltration, the presence of white plaque on it, which then becomes brown; characterized by swelling and bleeding of the gingival papillae. Like most inflammatory diseases of the oral cavity, stomatitis is accompanied by the presence of bad breath, a large number of leukocytes is determined in a laboratory scraping from the mucous membrane. Treatment of catarrhal stomatitis should be etiotropic: it is necessary to remove deposits of tartar, smoothing the sharp edges of the teeth. To accelerate healing, the mucous membrane is treated with a 3% hydrogen peroxide solution, the oral cavity is rinsed several times a day with warm solutions of chamomile or calendula.

Ulcerative stomatitis. The course of ulcerative stomatitis is more severe, the disease can develop independently or be the result of advanced catarrhal stomatitis. With ulcerative stomatitis, unlike catarrhal, the pathological process affects not only the surface layer of the oral mucosa, but its entire thickness. In this case, necrotic ulcers are formed, penetrating deep into the underlying tissues; these areas of necrosis can merge with each other and form extensive necrotic surfaces. The transition of the necrotic process to the bone tissue of the jaws and the development of osteomyelitis are possible.

Clinical manifestations in ulcerative stomatitis are similar to those in catarrhal (bad breath, hyperemia and swelling of the mucosa), but are more pronounced, the appearance of general intoxication: headache, weakness, fever up to 37,5^оC. Approximately on the 2-3rd day of the disease, whitish or dirty-gray plaques are formed on separate parts of the oral mucosa, covering the ulcerated surface. Saliva acquires a viscous consistency, the smell from the mouth is putrid. Any irritation of the mucous membrane causes severe pain. The disease is accompanied by an increase and soreness of regional lymph nodes. In the general analysis of blood, leukocytosis and an increase in the level of ESR are observed.

Treatment should begin as soon as possible. Antiseptic and deodorizing agents are used locally for irrigation: 0,1% potassium permanganate solution, 3% hydrogen peroxide solution, furacillin solution (1:5000), ethacridine lactate (rivanol), these drugs can be combined in various ways, but the presence hydrogen peroxide and potassium permanganate in any scheme is required.

22. Acute aphthous stomatitis and leukoplakia

Acute aphthous stomatitis. This disease is characterized by the appearance of single or multiple aphthae on the oral mucosa. Most often it affects people suffering from various allergies, rheumatism, diseases of the gastrointestinal tract, attacked by a viral infection.

The first symptoms of incipient aphthous stomatitis are general malaise, fever, apathy and depression, accompanied by pain in the mouth, a slight leukopenia and an increase in ESR to 45 mm / h are noted in the general blood test.

Then, aphthae appear on the mucous membrane of the oral cavity - small (with lentil grain) foci of a round or oval shape, clearly delimited from healthy areas by a narrow red border, in the center they are covered with a grayish-yellow coating due to the deposition of fibrin. In their development, they go through four stages: prodromal, aphthous, ulcerative and healing stage.

Aphthae can heal on their own, without a scar. In the treatment of aphthous stomatitis, rinsing the oral cavity with disinfectant solutions is locally prescribed, aphthae are treated with a 3% solution of methylene blue, sprinkled with a powder mixture consisting of nystatin, tetracycline and white clay.

General treatment involves the appointment of antibiotics (biomycin, tetracycline), antihistamines, anti-inflammatory drugs (acetylsalicylic acid, amidopyrine 500 mg 2-5 times a day).

Leukoplakia

Leukoplakia is a chronic disease of the oral mucosa, manifested by thickening of the mucosal epithelium, keratinization and desquamation; the most common localization is the buccal mucosa along the line of teeth closure, on the back and sides of the tongue, at the corner of the mouth. The disease begins, as a rule, asymptomatically, a slight itching or burning sensation is possible. Morphologically, leukoplakia is a focus of thickening of the mucous membrane of a whitish color, its size can vary from the size of a millet grain to the entire inner surface of the cheek. There are 3 forms of leukoplakia:

1) flat shape;

2) verrucous form, characterized by compaction and vegetation of the epithelium in the affected areas;

3) erosive-ulcerative form, which is dangerous due to the possibility of malignancy.

Treatment involves the elimination of all possible provoking factors: oral hygiene, abstinence from smoking, eating too hot or too spicy food, and avoiding alcoholic beverages. If the verrucous form is accompanied by the appearance of deep cracks, it is necessary to excise the lesion and its mandatory histological examination.

23. Chronic recurrent aphthous stomatitis (CRAS)

HRAS is considered not as a local pathological process, but as a manifestation of the disease of the whole organism.

The factors provoking relapses include trauma to the oral mucosa, hypothermia, exacerbation of diseases of the digestive system, stressful situations, and climatic and geographical factors.

The development of an allergic reaction in CRAS is accelerated in the presence of predisposing factors, among which heredity is generally recognized.

Characteristic morphological elements in CRAS are aphthae, which are usually localized in any area of the OM and have a development cycle of 8-10 days. Aftas are more often solitary, round or oval in shape, have regular outlines, bordered by a thin bright red rim. Elements of the lesion are localized more often on the hyperemic (with sympathetic tone) or pale base of the oral mucosa (with parasympathetic tone).

The size of the aft varies from finely punctate to 5 mm in diameter or more. They are covered with a yellowish-white fibrous film, which is on the same level with the mucous membrane or slightly protrudes above its level.

CRAS can be divided into several forms: fibrinous, necrotic, glandular, scarring, deforming, lichenoid.

The fibrinous form appears on the mucous membrane in the form of a yellowish spot with signs of hyperemia, on the surface of which fibrin precipitates, tightly soldered to the surrounding tissues.

In the necrotic form, a short-term vasospasm leads to necrosis of the epithelium, followed by ulceration. Necrotic plaque is not tightly soldered to the underlying tissue and is easily removed by scraping.

In cases of the glandular form, in addition to the oral mucosa, the small salivary glands in the area of the lips, tongue, and lymphopharyngeal ring are also involved in the inflammatory process. Areas of hyperemia appear, against which the salivary glands seem to be raised due to edema.

The scarring form is accompanied by damage to the acinar structures and connective tissue. The function of the salivary glands is markedly reduced. Healing goes with the formation of a rough scar.

The deforming form is characterized by a deeper destruction of the connective tissue up to the muscle layer. An ulcer in this form is sharply painful, has a migratory character, small erosions and aphthae often appear along its periphery.

In the case of the lichenoid form, limited areas of hyperemia appear on the oral mucosa, bordered by a whitish ridge of hyperplastic epithelium.

24. Changes that occur on the oral mucosa in various diseases

Since the oral mucosa is often involved in certain pathological processes occurring in the body, the study of its condition is very informative.

Gastrointestinal disease

Even in the absence of patient complaints about any disorders of the gastrointestinal tract, certain symptoms may appear on the mucous membrane, usually indicating an exacerbation of an existing chronic disease. The presence and color of plaque on the tongue is especially indicative. Coating of the tongue during exacerbations of chronic diseases of the gastrointestinal tract and some infectious diseases does not require specific treatment.

Diseases of the cardiovascular system

Cyanosis of the mucous membrane of the lips, cheeks, tongue, floor of the mouth quite often accompanies hypertension and some heart defects. In this case, often on the surface of the mucosa there is a burning sensation, tingling, itching.

Small-focal myocardial infarction is characterized by cyanotic color of the mucous membrane, its swelling, and dry mouth. In acute myocardial infarction, the mucous membrane becomes cyanotic, cracks appear on it, erosions, sometimes ulcers, and even hemorrhages.

Diseases of the blood

Granulocytosis, which in itself is characterized by a very vivid clinical picture, is also accompanied by ulcerative necrotic changes on the lips, tongue, gums, buccal surface of the mucous membrane, on the tonsils and even in the oropharynx.

Hypochromic iron deficiency and pernicious anemia. The main manifestations of these diseases in the oral cavity are burning, itching and tingling in the tongue, atrophy and deformation of the papillae of its mucosa, dry mouth.

Thrombocytopenia (Werlhof's disease) is characterized by recurrent bleeding (usually from the gums, but other localization is possible), which often occur unexpectedly against the background of complete well-being, without previous violation of the integrity of the mucous membrane.

Syndrome of disseminated intravascular coagulation. DIC can complicate the course of a number of diseases, such as sepsis, severe injuries, burn disease, complicated childbirth, and various poisonings. At the same time, changes also affect the outer integument of the body along with mucous membranes: elements of a rash appear, multiple hemorrhages under the skin and in the submucosal layer, bleeding of the skin and gums.

Psoriasis

In this disease, the back of the tongue is covered with red, pink and white areas, alternating with each other, the tongue becomes similar to a geographical map ("geographic tongue"), while the defects do not cause any discomfort to the patient.

25. Acute mechanical injury of the oral mucosa

Mechanical damage can be caused by acute trauma as a result of biting the mucosa while eating, an attack of epilepsy, a blow, preparation of teeth for crowns (bur, probe, disc), when filling teeth.

Open wounds

They often occur in practically healthy people from the simultaneous impact of a traumatic agent and quickly disappear after its elimination.

Excoriation is a lesion in which the layer of the mucosa itself is not affected, a pain symptom is expressed, but there may not be bleeding, which indicates that the papillary layer has not been opened.

Erosion is a superficial injury when the epithelial and papillary layers are involved, which is explained by the appearance of blood droplets, like "dew".

Clinical manifestations of wounds depend on the depth of the lesion, the type of injury, and vascular involvement.

The course of an open wound, regardless of the type of damage, goes through the following stages:

1) stage of hydration (exudation), which lasts 1-2 days. Patients complain of burning, pain, aggravated by eating, talking. There are pronounced hyperemia and edema around the lesion. Immediately after the injury, ice or a cold compress can be applied to the wound. The pain is relieved by the use of painkillers. The wound is washed;

2) stage of dehydration (after 1-3 days). The pain subsides. This stage is characterized by the formation of crusts on the skin and plaque on the mucosa. During this period, you can assign, in addition to anti-inflammatory drugs, enzymes;

3) stage of epithelialization. Epithelialization of acute traumatic lesions occurs quickly, within 1-3 days. When a secondary infection is attached, they do not heal for a long time. Healing is possible through scarring. Reparants have proven themselves well: vitamins A, E, groups B, C, K, their oil solutions.

closed wounds

Closed wound - hematoma - hemorrhage into the tissue surrounding the vessels. The hematoma undergoes changes over several stages, which are called the stages of the course of the hematoma:

1) red hematoma - 1st day. The color of the hematoma is due to hemorrhage into the surrounding tissues of red blood cells. In case of injury, vascular rupture, thrombosis, and the release of blood cells occur. Immediately after the injury, it is good to apply cold, carry out cryoapplication;

2) blue hematoma - 2-3rd day - due to venous congestion, changes in uniform elements. It is good to use FTL, anti-inflammatory therapy during this period;

3) green hematoma - 4-5th day. The color is due to the formation and release of hemasiderin;

4) yellow hematoma - 6-7th day. Resolving therapy is recommended: ranidase, lidase, hyaluronidase.

26. Chronic mechanical injury (CMT) of the oral mucosa

They are more common than acute. They are caused mainly by the following operating reasons: carious teeth, poor-quality fillings, dentures and their clasps, lack of a contact point, tartar.

The process develops over months, years. Initially, the phenomena of catarrhal inflammation (hyperemia, swelling, soreness) appear in the tissue. But with a long course of the process, hyperemia from bright red becomes cyanotic, the edges and bases of the lesion become denser not only due to edema, but also as a result of the development of dense connective tissue.

During chronic mechanical injury, the following stages can be distinguished:

1) catarrhal stage. It is characterized by burning, tingling, feeling of soreness. Possible glossalgia. Objectively: hyperemia and edema develop on the mucosa in places according to the action of the traumatic factor.

2) violations of the integrity of the epithelium (erosion, aphtha, ulcer). More often they are localized on the lateral surfaces of the tongue, cheeks, hard palate. A long-lasting ulcer can spread to muscle tissue, and move from the palate to the bone, causing its perforation. Usually the edges and bottom of the ulcer are hyperemic, edematous, dense on palpation, slightly painful. The epithelium normally regenerates within 3 days. If erosion, aphtha, ulcer do not pass to the next stage, but persist for 14 days, then rebirth occurs.

3) the stage of proliferative processes. This is vegetation, papillomatosis.

A type of chronic traumatic injury to the mucosa is decubitus or prosthetic stomatitis. Under the prosthesis, catarrh occurs first, then erosion and even an ulcer, which can disappear immediately after the timely correction of the prosthesis. Prolonged wearing of such a prosthesis leads to the development of a chronic inflammatory process, which is accompanied by the growth of connective tissue in the area of injury - lobular fibroma or papillomatosis occurs.

The oral cavity is being rehabilitated. Antiseptic rinses with potassium permanganate 1:5000, furatsilin 1:5000, 1-2% sodium bicarbonate solution (soda), heparin applications on the mucosa are shown. In the stage of violation of the integrity of the epithelial cover, apply:

1) enzymes;

2) anti-inflammatory and antiseptic applications, painkillers;

3) from the 3rd day - applications of keratoplastic agents: galascarbine, rosehip oil, keratolin.

In traumatic lesions, if the ulcer does not heal within 10-14 days during treatment, a biopsy should be done.

27. Chemical damage to the oral mucosa, types of anesthesia

Chemical damage to the oral mucosa can result from acute or chronic exposure to various substances.

An acute lesion occurs when potent substances accidentally enter the mucous membrane.

Medication-induced lesions of the oral mucosa are more common (50% of all lesions).

These mucosal burns are the result of mistakes made by dentists when treating with the following drugs: silver nitrate, resorcinol-formalin mixture, EDTA, acid for expanding root canals (nitric, sulfuric, aqua regia). When they get on the mucous membrane, they cause severe burns, the patient feels a sharp pain, a strong burning sensation.

Burn stages:

1) stage of intoxication (hydration, catarrhal changes);

2) necrosis stage. In the affected area, coagulation of the mucosa occurs, and, depending on the duration and strength of the impact of the pathogenic object, necrosis occurs, followed by the formation of erosion or ulcers. With acid necrosis, the affected area is covered with a dense film (brown from sulfuric acid, yellow from nitric acid, white-gray from other acids). The mucosa around and the subject are inflamed, tightly soldered to the tissues of necrosis. Alkali burns have a loose surface, their consistency is similar to jelly. After rejection of necrotic masses, extensive erosive surfaces and ulcers are formed;

3) scarring stage. Erosion or ulcer, covered with necrotic plaque, passes into the next stage - the stage of scarring, epithelialization. Possible vegetation, papillomatosis with symptoms of hyperkeratosis.

When providing first aid, one must act on the principle of neutralizing acids with alkalis, and vice versa. Abundant rinsing, irrigation, washing. The simplest thing that can be done for acid burns is to wash the affected area with soapy water, 1-2% sodium bicarbonate solution. Alkalis are neutralized with weak solutions of acids - 0,5-1% solutions of citric, acetic acids, 0,1% hydrochloric acid.

Patients are prescribed a diet, cold on the affected areas.

The emerging necrosis is treated with painkillers, antiseptics in the form of applications, nitrofuran preparations (such as furacilin, furazolidone, furagin). The necrotic film is removed by enzymes. In order to regenerate the epithelial layer, applications of keratoplastic agents are used: vinylin, oil solutions of 1% citral, vitamin A and E concentrate, cigerol, keratolin.

In the formation of contractures, surgical excision of scars is used.

Drug-induced lesions have a specific management, which consists in the use of special antidotes.

28. Chronic chemical injury (CCT) of the oral mucosa

Chronic chemical injuries of the mucous membrane have a special character of manifestation. In some cases, they can be in the form of a delayed-type allergic reaction, in others - in the form of intoxication of the body.

Prolonged contact with pesticides causes chronic inflammation of the oral mucosa, exfoliative cheilitis, leukoplakia of the palate, hyperkeratosis.

Mucosal changes in the form of hyperkeratosis are caused by the action of phenol, mercury, anthracite, liquid resins, arsenic, etc.

Ionizing radiation

Radiation sickness.

There are acute and chronic forms of radiation sickness (ARS). Acute develops after a single exposure to doses of 100-1000 rad. It appears in four periods.

Clinical forms of ARS:

1) typical;

2) intestinal;

3) toxic;

4) nervous.

The period of the primary reaction develops 1-2 hours after irradiation and lasts up to 2 days.

Nausea, vomiting, dyspepsia appear, salivation is disturbed, neurological symptoms are expressed, leukocytes decrease in the peripheral blood.

Clinic: dryness or hypersalivation in the oral cavity, decrease in taste and sensitivity of the mucous membrane, swelling of the lips and mucous membranes of other departments, hyperemia, petechial hemorrhages appear.

It is recommended to reduce the intake of radioisotopes into the body:

1) take a shower;

2) wash the mucous membranes with soda solution;

3) wash the stomach, intestines;

4) prescribe radioprotectors.

Latent period - imaginary well-being (from several hours to 2-5 weeks). During this period, clinical symptoms are not expressed. Agranulocytosis is the main manifestation that leads to a violation of the body's defenses.

On ORM - xerostomia, which can be removed with pilocarpine. It is possible to take bitterness, which have salivary properties (coltsfoot, yarrow). This is a period of active rehabilitation of the oral cavity, taking drugs that restore or protect the activity of hematopoietic organs.

The third period (the height of the disease). Against the background of a sharp deterioration in the general condition in the oral cavity, a clinical picture of a severe form of ulcerative necrotic gingivostomatitis occurs. The mucosa swells, the gingival papillae loosen, necrotic, the bone tissue of the alveolar process is resorbed, necrotized (radiation necrosis), sequestered, and jaw fractures are possible.

29. Diagnosis of the state of the human body by language

Of all the parts of the mucous membrane of the oral cavity, the surface of the tongue reacts most sensitively and early to various changes in the human body. Informational value is the color of the tongue, humidity, the presence and location of furrows, the state of individual zones, which are a reflection of certain organs, the presence and color of plaque. So, the anterior third corresponds to the heart and lungs in the tongue, the middle third corresponds to the stomach, spleen and pancreas, the intestines are projected onto the root of the tongue, the liver and kidneys are projected onto its lateral surfaces, the fold running along the middle of the tongue reflects the state of the spine. Increased sensitivity and discoloration of various areas indicate a violation of the functioning of those organs with which these areas are associated, the curvature of the median fold indicates damage to the spine, and the places of the bends indirectly indicate the suffering department. Uneven desquamation and regeneration of the epithelium are characteristic of lesions of the gastrointestinal tract, diathesis, helminthic invasions, and toxicosis during pregnancy. Tremor of the tongue indicates dysfunction of the autonomic nervous system, beginning neurosis, thyrotoxicosis. The presence of cracks, deep folds in the tongue indicates a violation of the bioenergetics of the body; the appearance of persistent imprints of teeth on it indicates a violation of the digestive processes.

Diagnosis by the color of plaque and the color of the mucous membrane of the tongue:

1) tongue without plaque, cracks and lines, pale pink - the body is healthy;

2) yellow plaque - a violation of the functions of the digestive organs;

3) dense white coating - intoxication, constipation;

4) dense white plaque, thinning over time - a sign of improvement in the patient's condition;

5) black plaque - severe chronic dysfunction of the digestive organs, accompanied by dehydration and acidosis;

6) brown plaque - diseases of the lungs and gastrointestinal tract;

7) pale tongue - anemia and exhaustion of the body;

8) shiny, smooth tongue - anemia;

9) purple tongue - diseases of the blood and lungs in an advanced stage;

10) red tongue - disorders of the cardiovascular system, lungs and bronchi, hematopoietic system, also indicates an infectious process;

11) dark red tongue - speaks of the same disorders, but the prognosis is worse, the development of a life-threatening condition is possible;

12) blue tongue - diseases of the cardiovascular system, kidneys, lungs in an advanced stage;

13) bright blue tongue - a pre-agonal state.

30. Collagenoses

collagen diseases - a widespread group of diseases; most often they affect women of young and middle age. They are allergic in nature and are accompanied by the development of autoimmune reactions that damage the connective tissue of the body. The course of collagenosis is long, cyclic, progressive, accompanied by an increase in body temperature. In parallel, signs of allergy are detected, their development is provoked by various exogenous factors, such as cooling, injury, infection in the body, and medication.

Rheumatism

The most common manifestations of rheumatism in the maxillofacial region are pallor of the skin of the face, anemic mucous membranes, catarrhal inflammation of the gums, their thickening in the form of a roller, the severity of the vascular pattern, the formation of precarious chalky spots, multiple caries.

Rheumatoid arthritis

With this form of collagenosis, the color of the teeth changes, the enamel becomes thinner, light yellow spots (translucent dentin) appear on it, the edges of the teeth are erased and can be completely destroyed, vasculitis, submucosal hemorrhages, and petechial rashes on the mucosa may develop.

In the temporomandibular joint, articular syndrome is expressed, which is manifested by short-term stiffness of the masticatory muscles, limitation and pain in opening the mouth, and a feeling of discomfort in this joint.

Systemic lupus erythematosus

In addition to the presence of characteristic erythematous spots on the face in the form of a butterfly, with systemic lupus erythematosus, hard tissues of the teeth are affected, due to which their color changes, they become dull, chalk spots appear in the cervical zone of the teeth, areas of enamel necrosis with yellow or black pigmentation. The mucous membrane of the oral cavity at this time becomes hyperemic, edematous; along the line of closure of the molars, foci of clouded epithelium, the so-called lupus spots, rising above the rest of the surface, can form. In the acute stage of systemic lupus erythematosus in the oral cavity, a sharp fiery red lesion of the entire mucous membrane can be observed, on which erythematous edematous areas with clear boundaries are distinguished, as well as foci of desquamated epithelium, erosion in the soft palate.

Systemic scleroderma (progressive systemic sclerosis)

This disease is manifested by severe microcirculation disorders and the development of sclerotic processes leading to tissue thickening. At the same time, the appearance of a person changes significantly: the mobility of the soft tissues of the face decreases, facial expressions are almost absent, wrinkles are smoothed out, a microstoma develops - a decrease in the mouth opening, the lips are thinned, due to the shortening of the frenulum of the tongue, its mobility is limited.

31. Diseases of the trigeminal nerve

Trigeminal neuralgia. The disease is manifested by bouts of pain along one or more branches of the trigeminal nerve, it is not uncommon.

Trigeminal neuralgia is a polyetiological disease, its causes can be various infections (syphilis, tuberculosis, malaria, influenza, tonsillitis), gastrointestinal diseases, acute and chronic intoxications, oncological lesions, vascular changes in the brain, such as sclerosis, abnormal development , dental diseases (sinusitis, chronic periodontitis, the presence of an impacted tooth, cysts, bite pathology), arachnoiditis.

Allocate true and secondary neuralgia. The true (or idiopathic) neuralgia is an independent disease, the cause of which cannot be established. Secondary (or symptomatic) neuralgia - this is a companion of any underlying disease (tumors, infections, intoxication, stomatogenic processes, brain diseases). Clinically, trigeminal neuralgia is manifested by attacks of sharp, jerking or cutting short-term pain, a burning sensation in a certain area of the face, the area of the oral mucosa, or in the jaw itself. The pain is unbearable, it can radiate to the neck, neck, temples, patients cannot speak, eat, turn their heads, as they are afraid to provoke a new pain attack. The pain ends as quickly as it begins. A painful attack may be accompanied by dilated pupils, hyperemia of the area of innervation of the trigeminal nerve, increased salivation, lacrimation, an increase in the amount of nasal secretion, convulsive contractions of the mimic muscles.

One of the branches of the trigeminal nerve is usually affected: with neuralgia of the first branch (involved in the pathological process less often than the second and third), the pain is concentrated in the forehead, superciliary arches, anterior temporal region; neuralgia of the second branch is characterized by pain in the region of the upper lip, lower eyelid, wing of the nose, nasolabial groove, zygomatic zone, upper teeth, soft and hard palate; with neuralgia of the third branch, pain is determined in the region of the lower lip of the chin, teeth, cheeks, and tongue.

During palpation of the zones innervated by the trigeminal nerve, with its neuralgia, paresthesia of the skin is determined, the most painful points corresponding to the places where its branches exit: the eyebrow, infraorbital and mental foramina.

Treatment of trigeminal neuralgia should include the elimination of the primary disease, along with the aim of relieving painful symptoms for the patient, painkillers, B vitamins, prozerin, tegretol, chlorpromazine can be prescribed, in some patients a pronounced positive effect was observed after the use of bee venom, recommend the appointment of anticonvulsants and blockade of the affected branch with novocaine.

32. Periomaxillary abscesses and phlegmons

Abscess - limited purulent inflammation of the cellular tissue with the formation of a cavity (and a granulation shaft), the purulent-inflammatory process is limited to the limits of any one isolated cellular space.

Phlegmon - acute diffuse purulent inflammation of the tissue (subcutaneous, intermuscular, interfascial), characterized by a tendency to further spread; diffuse purulent-inflammatory process, extending to 2-3 or more adjacent cellular spaces.

Cellulite - serous inflammatory process in certain cellular spaces (MCF). If the inflammatory process acquires a diffuse character, then it is already interpreted as a phlegmon.

Etiology: These two pathological processes are considered together in view of the great difficulty in differential diagnosis.

The main features of the topical diagnosis of purulent maxillary phlegmon of odontogenic origin:

1) a sign of "causal tooth";

2) a sign of "severity of inflammatory infiltrate" of the soft tissues of the maxillary region;

3) sign "impaired motor function of the lower jaw";

4) sign "difficulty swallowing"

Classifications of abscesses and phlegmons of the maxillofacial region:

1) according to topographic and anatomical features;

2) at the location of the fiber in which phlegmon appear;

3) according to the initial localization of the infectious-inflammatory process, highlighting osteophlegmons and adenophlegmons;

4) by the nature of the exudate.

Clinical picture: inflammation, as a rule, begins acutely. There is a rapid increase in local changes: infiltration, hyperemia, pain. In most patients, there is an increase in body temperature up to 38-40 ° C, in some cases there is a chill, which is replaced by a feeling of heat. In addition, general weakness is noted, which is due to the phenomenon of intoxication.

The following stages of the inflammatory process are distinguished:

1) serous inflammation;

2) serous-purulent inflammation;

3) the stage of delimitation of the infectious focus, cleansing the surgical wound with proliferation phenomena.

Depending on the ratio of the main components of the inflammatory reaction, phlegmon with a predominance of exudation phenomena (serous, purulent) and phlegmon with a predominance of alteration phenomena (putrefactive necrotic) are distinguished.

The ultimate goal of the treatment of patients with abscesses and phlegmon of the maxillofacial area is the elimination of the infectious process and the complete restoration of impaired body functions in the shortest possible time.

33. Phlegmon of the submandibular region

Among the phlegmon located near the lower jaw, the most common phlegmon of the submandibular triangle. It occurs as a result of the spread of infection from inflammatory foci in the region of the lower large molars.

Its initial clinical manifestations are characterized by the appearance of edema, and then infiltration under the lower edge of the body of the lower jaw. The infiltrate spreads relatively quickly to the entire submandibular region. Puffiness of soft tissues passes to the cheek area and the upper lateral part of the neck. The skin in the submandibular region is stretched, shiny, hyperemic, not taken into a fold. Mouth opening is usually not affected. In the oral cavity on the side of the purulent-inflammatory focus - moderate swelling and hyperemia of the mucous membrane.

With an isolated lesion of the submandibular region, external access is used. A skin incision 6-7 cm long is made in the submandibular region along a line connecting a point 2 cm below the top of the jaw angle with the middle of the chin. This direction of the incision reduces the likelihood of damage to the marginal branch of the facial nerve, which in 25% of people descends in a loop below the base of the mandible. The subcutaneous adipose tissue and the subcutaneous muscle of the neck with the superficial fascia of the neck enveloping it are dissected over the entire length of the skin incision. Above the grooved probe, the superficial plate of the own fascia of the neck is also dissected. Then, stratifying and pushing the fiber with a hemostatic clamp, they penetrate between the edge of the jaw and the submandibular salivary gland into the depths of the submandibular triangle - to the center of the infectious and inflammatory focus. If the facial artery and the anterior facial vein meet on the way, it is better to cross them between the ligatures. In order to avoid damage to the facial artery and anterior facial vein, when dissecting tissues during the operation, do not approach the bone of the body of the lower jaw with a scalpel, over the edge. This improves access to the infectious focus and reduces the likelihood of secondary bleeding.

An abscess and phlegmon of the submental region is opened parallel to the edge of the lower jaw or along the midline (in the direction from the lower jaw to the hyoid bone), the skin, subcutaneous fatty tissue and superficial fascia are dissected; to the abscess penetrate the blunt way.

The prognosis for isolated phlegmon of the submandibular and submental areas in the case of timely complex treatment is usually favorable.

Duration of inpatient treatment of patients with phlegmon of the submandibular region - 12 days, submental region - 6-8 days; the total duration of temporary disability for patients with phlegmon of the submandibular region is 15-16 days, the submental region is 12-14 days.

34. Phlegmon of the buccal region, posterior-mandibular, pterygo-mandibular and parapharyngeal spaces

The configuration of the face is sharply changed due to infiltration, swelling of the cheeks and adjacent tissues: there is swelling of the eyelids, lips, and sometimes in the submandibular region.

The choice of operative access depends on the localization of the infiltrate. The incision is made either from the side of the oral cavity, drawing it along the line of closure of the teeth, taking into account the course of the parotid duct, or from the side of the skin, taking into account the course of the facial nerve. After evacuation of purulent exudate, drainage is introduced into the wound.

Phlegmon behind the mandibular space

Surgical opening of the phlegmon is performed with a vertical incision parallel to the posterior edge of the lower jaw branch and, depending on the spread of the abscess, the angle of the jaw is included. Drain the cavity with a rubber tube.

Phlegmon of the pterygo-mandibular space

Surgical opening of the phlegmon of the pterygo-maxillary space is performed from the side of the skin in the submandibular region with an incision bordering the angle of the lower jaw, departing from the edge of the bone by 2 cm. A part of the tendon of the medial pterygoid muscle is cut off with a scalpel, the edges of the entrance to the cellular space are bluntly pushed apart with a hemostatic clamp. Purulent exudate comes out from under the muscles under pressure, a rubber outlet tube is inserted into the cavity.

Phlegmon of the peripharyngeal space

Surgical opening of the abscess of the peripharyngeal space in the initial phase is performed by an intraoral incision passing somewhat medially and posteriorly from the pterygo-mandibular fold, the tissues are dissected to a depth of 7-8 mm, and then stratified with a blunt hemostatic forceps, adhering to the inner surface of the medial pterygoid muscle, until pus is obtained .

With a phlegmon of the peripharyngeal space that has spread downward (below the dentition of the lower jaw), the intraoral opening of the abscess becomes ineffective, so it is immediately necessary to resort to an incision from the side of the submandibular triangle closer to the angle of the lower jaw.

After dissection of the skin, subcutaneous tissue, superficial fascia, subcutaneous muscle and outer leaf of the own fascia of the neck, the inner surface of the medial pterygoid muscle is found and the tissue is bluntly stratified along it until pus is obtained. After a digital revision of the abscess and combining all its spurs into one common cavity for drainage, a tube and a loose-gauze swab moistened with an enzyme solution are inserted on the first day.

The duration of inpatient treatment of patients with phlegmon of the pterygo-mandibular space - 6-8 days, peripharyngeal space - 12-14 days; the total duration of temporary disability for patients with phlegmon of the pterygo-mandibular space - 10-12 days, peripharyngeal - 16-18 days.

35. Phlegmon of the floor of the mouth

Phlegmon of the floor of the mouth is a purulent disease, when the sublingual, submandibular regions, submental triangle are affected in different combinations.

With the diffuse nature of phlegmon, only wide incisions can be recommended parallel to the edge of the lower jaw, retreating from it by 2 cm. This incision can be made according to indications of any length up to the collar with partial clipping of the attachment of the maxillohyoid muscle on both sides (for 1,5- 2 cm).

With a spilled abscess that has descended far, it can be opened with another collar incision in the region of its lower edge, passing along the upper cervical fold. Both methods of opening provide good drainage, comply with the laws of purulent surgery.

Putrid-necrotic phlegmon of the floor of the mouth is opened with a collar-shaped incision. It can be recommended to make only wide incisions (which achieve drainage and aeration of the tissues) parallel to the edge of the lower jaw, retreating from it by 2 cm. 1,5-2 cm). With a spilled abscess that has descended far, it can be opened with another collar incision in the region of its lower edge, passing along the upper cervical fold. Both methods of opening provide good drainage, comply with the laws of purulent surgery. All cellular spaces (submandibular, submental, sublingual) involved in the inflammatory process are widely opened and drained. At the same time excised necrotic tissue.

With the localization of putrefactive-necrotic phlegmon in other cellular spaces, they are widely opened and drained from the side of the skin according to generally accepted rules.

Thus, surgical treatment for putrefactive-necrotic phlegmon in a number of cases includes tracheotomy with tracheostomy, wide opening of phlegmon, necrotomy, necrectomy, removal of the causative tooth (with the odontogenic nature of the disease), etc.

Pathogenetic treatment: local oxygenation, achieved by periodic insufflation of oxygen through a catheter into the wound, (HBO) tissues.

Regional infusion of antibiotics is carried out. Proteolytic enzymes are widely used.

For common, extensive phlegmon, a hyperergic reaction of the body is characteristic, they are often complicated by mediastinitis, thrombophlebitis and thrombosis of the vessels of the face and brain, sinuses of the dura mater, sepsis.

Hemo-, lymphosorption, lymphatic drainage, plasmapheresis should be widely used. In the local treatment of wounds, it is advisable to use local dialysis, vacuum suction of exudate, sorbents, immobilized enzymes.

36. Etiology, pathogenesis and pathological anatomy of osteomyelitis

Any microorganism can cause osteomyelitis, but its main causative agent is Staphylococcus aureus. However, since the mid-70s XNUMXth century the role of gram-negative bacteria has increased, in particular Proteus vulgaris, Pseudomonas aeruginosa, Escherichia coli and Klebsiella, which are more often sown in association with staphylococcus aureus.

There are many theories of the pathogenesis of osteomyelitis. The most famous of them are vascular, allergic, neuroreflex.

In the osteomyelitic focus, proliferative changes in the periosteum and Haversian canals compress the vessels from the outside, and swelling of the walls of the vessels themselves reduces their lumen from the inside. All this makes it difficult and disrupts blood circulation in the bones, contributing to the occurrence of osteomyelitis.

According to the neuroreflex theory, the occurrence of osteomyelitis is promoted by a prolonged reflex vasospasm with impaired blood circulation.

In the pathogenesis of acute osteomyelitis, autogenous sources of microflora are of particular importance. Foci of latent or dormant infection in carious teeth, tonsils, constantly releasing toxins and decay products, contribute to the development of a delayed-type allergic reaction, create a predisposition of the body to the onset of the disease. In this situation, in a sensitized organism, nonspecific stimuli play the role of a resolving factor and can cause aseptic inflammation in the bones. Under these conditions, when microbes enter the bloodstream, it is converted into acute hematogenous osteomyelitis. On the 1st day, reactive inflammation phenomena are noted in the bone marrow: hyperemia, dilation of blood vessels, blood stasis with the release of leukocytes and erythrocytes through the altered vascular wall, intercellular infiltration and serous impregnation. On the 3rd-5th day, the medullary cavity is filled with red and yellow bone marrow. In some of its areas, accumulations of eosinophils and segmented neutrophils, single plasma cells are found. On the 10-15th day, purulent infiltration progresses with the development of severe bone marrow necrosis throughout; sharply dilated vessels with foci of hemorrhages between the bone crossbars, multiple accumulations of exudate with a huge number of decaying leukocytes are revealed. On the 20-30th day, the phenomena of acute inflammation persist. Fields filled with necrotic masses, detritus and surrounded by large accumulations of segmented neutrophils and lymphocytes are visible in the bone marrow. On the 35-45th day of the disease, necrosis extends to almost all elements of the bone tissue, the cortical substance becomes thinner. The bone continues to collapse, there is no endosteal formation, the cavities are filled with homogeneous masses, in which sequesters are found surrounded by purulent exudate. Sequesters are adjacent to necrotic tissue, which, without sharp boundaries, passes into fibrous connective tissue.

37. Clinic and diagnosis of acute odontogenic osteomyelitis

With a relatively slow development of osteomyelitis, the initial symptom is pain in the region of the causative tooth. Percussion of the tooth is acutely painful, first weakened, and then its significant mobility is detected. The mucous membrane in the area of the gingival margin on both sides is edematous and hyperemic. Palpation of this area is painful.

Body temperature increases to 37,5-38^оC, more often patients experience general malaise. A similar formation of osteomyelitis may resemble a picture of periostitis. With the active dynamics of osteomyelitis that has arisen in a certain area of the jaw, the pain is rapidly spreading and intensifying. In the next few hours, body temperature reaches 40^оC. There is a chill. In especially severe cases, twilight states are noted in patients.

When examining the oral cavity, a picture of multiple periodontitis is revealed: the teeth adjacent to the causative ones are mobile, painful on percussion. The mucous membrane of the gums is sharply hyperemic, loose and edematous.

Subperiosteal abscess occurs early. Interest in the inflammatory process of masticatory muscles causes their contracture. At the height of the development of an acute process, a decrease in the sensitivity of the skin of the chin area (Vincent's symptom) is determined, which is the result of compression of the lower alveolar nerve by inflammatory exudate. Already in the acute period, lymphadenopathy of regional lymph nodes is noted.

Under favorable conditions, purulent exudate breaks under the periosteum and, melting the mucous membrane, pours into the oral cavity. Quite often, thus, osteomyelitis is complicated by phlegmon.

The acute stage of osteomyelitis of the jaws lasts from 7 to 14 days. The transition to the subacute stage occurs during the formation of a fistulous tract, which ensures the outflow of exudate from the focus of inflammation.

In subacute osteomyelitis of the jaw, pain decreases, inflammation of the oral mucosa subsides, body temperature drops to subfebrile, blood and urine tests are close to normal. Pus is abundantly secreted from the fistula. Pathologically, the subacute stage of osteomyelitis is characterized by a gradual limitation of the area of bone lesion and the beginning of the formation of sequesters. In the same period, along with the necrotic process, reparative phenomena are observed. On the radiograph, an area of osteoporosis of the bone with a noticeable border between healthy and affected tissue is determined.

Subacute osteomyelitis lasts an average of 4-8 days and without noticeable signs becomes chronic.

The chronic form of osteomyelitis of the jaws can last from 4-6 days to several months. The final outcome of chronic osteomyelitis is the final rejection of necrotic bone areas with the formation of sequesters. Self-healing occurs only after the elimination of all sequesters through the fistulous course, but treatment is still mandatory.

38. Treatment of osteomyelitis

In acute osteomyelitis of the jaw, early wide periostotomy is indicated to reduce intraosseous pressure by ensuring the outflow of exudate and preventing the spread of the process to neighboring areas. It is also necessary to eliminate the main factor that caused the development of osteomyelitis (removal of the causative tooth). Tooth extraction must be combined with antibiotic therapy.

You can also use the method of intraosseous washing. To do this, two thick needles are inserted through the cortical plate into the thickness of the bone marrow. The first - at one pole of the border of the bone lesion, the second - at the other. An isotonic sodium chloride solution with an antiseptic or antibiotic is dripped through the first needle, and the liquid flows out through the second needle. The use of the method contributes to the rapid relief of the process, the removal of intoxication, and the prevention of complications.

In the subacute stage of osteomyelitis, the previously prescribed therapy is continued. In the chronic stage with the end of the formation of sequesters, it is necessary to choose the right time for surgical intervention. Removal of sequesters should be done with their final rejection, without injuring a healthy bone; on roentgenograms the sequesters freely lying in a sequestral cavity are visible.

Sequestrectomy is performed, depending on the area of the jaw lesion, either under local anesthesia or under general anesthesia. The approach to the sequester cavity is usually determined by the exit site of the fistulous tract. A wide incision exposes the bone. With a preserved cortical plate, it is trepanned in the place where it is pierced by the fistulous tract. Curettage spoon remove sequesters, granulations. Destruction of the natural barrier along the periphery of the sequester cavity should be avoided. If a sequester that has not yet completely separated is found, it should not be forcibly separated. It is necessary to leave it with the expectation of self-rejection and removal through the wound. The sequester cavity is washed with a solution of hydrogen peroxide and filled with an iodoform swab, the end of which is brought into the wound. The edges of the wound are sutured.

In the event of a spontaneous fracture of the lower jaw with the formation of a defect, bone grafting is indicated. After sequestrectomy and the creation of receptive sites on the fragments, the graft is placed overlay and strengthened with wire sutures.

The teeth involved in the inflammatory process and become mobile can become stronger as the acute events subside. However, the preservation of such teeth sometimes requires treatment similar to that of periodontal disease.

39. Modern filling materials

Filling is the restoration of the anatomy and function of the destroyed part of the tooth. Accordingly, the materials used for this purpose are called filling materials.

Filling materials are divided into four groups.

1. Filling materials for permanent fillings.

2. Temporary filling materials (water dentin, dentin paste, tempo, zinc-eugenol cements).

3. Materials for medical pads.

4. Materials for filling root canals.

Requirements for permanent filling materials.

1. Technological (or manipulation) requirements for the initial uncured material:

1) the final form of the material should contain no more than two components that are easily mixed before filling;

2) after mixing, the material should acquire plasticity or a consistency that is convenient for filling the cavity and forming an anatomical shape;

3) the filling composition after mixing must have a certain working time, during which it retains plasticity and the ability to form (usually 1,5-2 minutes);

4) the curing time (the period of transition from a plastic state to a solid state) should not be too long, usually 5-7 minutes;

5) curing must occur in the presence of moisture and at a temperature not exceeding 37^оC.

2. Functional requirements, i.e. requirements for the cured material. The filling material in all respects should approach the indicators of the hard tissues of the tooth:

1) exhibit stable over time and in a humid environment;

2) during curing, give minimal shrinkage;

3) have a certain compressive strength;

4) have low water absorption and solubility;

5) have a coefficient of thermal expansion close to the coefficient of thermal expansion of the hard tissues of the tooth;

6) have low thermal conductivity.

3. Biological requirements: the components of the filling material should not have a toxic, sensitizing effect on the tissues of the tooth and oral cavity organs.

4. Aesthetic requirements:

1) the filling material must match the color, shades, structure, transparency of the hard tissues of the tooth;

2) the seal must have color stability and not change the quality of the surface during operation.

40. Composite materials. Definition, development history

In the 40s. 30th century Acrylic quick-hardening plastics were created, in which the monomer was methyl methacrylate, and the polymer was polymethyl methacrylate. Their polymerization was carried out thanks to the initiator system BPO-Amin (benzoyl and amine peroxide) under the influence of oral temperature (40-XNUMX^оC), e.g. Acryloxide, Carbodent. The specified group of materials is characterized by the following properties:

1) low adhesion to tooth tissues;

2) high marginal permeability, which leads to a violation of the marginal fit of the filling, the development of secondary caries and inflammation of the pulp;

3) insufficient strength;

4) high water absorption;

5) significant shrinkage during polymerization, about 21%;

6) discrepancy between the coefficient of thermal expansion and that of the hard tissues of the tooth;

7) high toxicity;

8) low aesthetics, mainly due to a change in the color of the filling (yellowing) during the oxidation of the amine compound.

In 1962, RL BOWEN proposed a material in which BIS-GMA, with a higher molecular weight, was used as a monomer instead of methyl methacrylate, and quartz treated with silanes as a filler. Thus, RL BOWEN laid the foundation for the development of composite materials. In addition, in 1965, M. Buonocore made the observation that the adhesion of the filling material to the tissues of the tooth improves significantly after pre-treatment of the enamel with phosphoric acid. These two scientific achievements served as prerequisites for the development of adhesive methods for the restoration of tooth tissues. The first composites were macrofilled, with the particle size of the inorganic filler from 10 to 100 microns. In 1977, microfilled composites were developed (particle size of inorganic filler from 0,0007 to 0,04 µm). In 1980, hybrid composite materials appeared, in which the inorganic filler contains a mixture of micro- and macroparticles. In 1970, M. Buonocore published a report on filling fissures with a material that polymerizes under the influence of ultraviolet rays, and since 1977, the production of light-cured composites polymerized under the action of blue color (wavelength - 450 nm) began.

Composite materials are polymeric filling materials containing more than 50% by weight of finished inorganic filler treated with silanes, therefore composite materials are called filled polymers, in contrast to unfilled ones, which contain less than 50% inorganic filler (for example: Acryloxide - 12%, Carbodent - 43%.

41. Classification of composite materials

The main components of composites are an organic matrix and an inorganic filler.

There is the following classification of composite materials.

1. Depending on the particle size of the inorganic filler and the degree of filling, the following are distinguished:

1) macro-filled (ordinary, macro-filled) composites. The particle size of the inorganic filler is from 5 to 100 microns, the content of the inorganic filler is 75-80% by weight, 50-60% by volume;

2) composites with small particles (microfilled). The particle size of the inorganic filler is 1-10 microns;

3) microfilled (microfiled) composites. The particle size of the inorganic filler is from 0,0007 to 0,04 microns, the content of the inorganic filler is 30-60% by weight, 20-30% by volume. Depending on the shape of the inorganic filler, microfilled composites are divided into:

a) inhomogeneous (contain microparticles and conglomerates of prepolymerized microparticles);

b) homogeneous (contain microparticles).

4) hybrid composites are a mixture of conventional large particles and microparticles. Most often, composites of this group contain particles ranging in size from 0,004 to 50 µm. Hybrid composites, which include particles no larger than 1-3,5 microns, are finely dispersed. The amount of inorganic filler by weight is 75-85%, by volume 64% or more.

2. According to the purpose, composites are distinguished:

1) class A for filling carious cavities of class I-II (according to Black);

2) class B for filling carious cavities III, IV, V classes;

3) universal composites (inhomogeneous microfilled, finely dispersed, hybrid).

3. Depending on the type of the original form and the method of curing, the materials are divided into:

1) light-cured (one paste);

2) chemical curing materials (self-curing):

a) type "paste-paste";

b) "powder - liquid" type.

42. Macro-filled composite materials

The first composite, proposed by Bowen in 1962, had quartz flour as a filler with particle sizes up to 30 microns. When comparing macrofilled composites with traditional filling materials (unfilled polymer monomers), their lower polymerization shrinkage and water absorption, higher tensile and compressive strength (by 2,5 times), and lower coefficient of thermal expansion were noted. Nevertheless, long-term clinical trials have shown that fillings made of macrofilled composites are poorly polished, change in color, and there is a pronounced abrasion of the filling and the antagonist tooth.

The main disadvantage of macrophiles was the presence of micropores on the surface of the filling, or roughness. The roughness arises due to the significant size and hardness of the inorganic filler particles compared to the organic matrix, as well as the polygonal shape of the inorganic particles, so they quickly crumble when polished and chewed. As a result, there is a significant abrasion of the filling and the antagonist tooth (100-150 microns per year), the fillings are poorly polished, surface and subsurface pores, they need to be eliminated (by cleaning etching, washing, applying adhesive, polymerizing the adhesive, applying and polymerizing the composite); otherwise, they will be stained. Next, the final finishing (polishing) of the filling is performed. First, rubber, plastic heads, flexible disks, strips are used, and then polishing pastes. Most finishing companies produce two types of pastes: for preliminary and final polishing, which differ from each other in the degree of dispersion of the abrasive. It is necessary to carefully study the instructions, since the time of polishing with pastes of different companies is different. For example: Dent-sply polishing pastes: polishing should be started with Prisma Gloss paste for 63 seconds on each surface separately. Polishing with this paste gives the surface a wet sheen (the filling shines when wet with saliva). Next, the "Frisra Gloss Exstra Fine" paste is used (also for 60 from each surface), which will give a dry shine (when drying the tooth with an air jet, the shine of the composite is comparable to the shine of enamel). If these rules are not observed, it is impossible to achieve an aesthetic optimum. The patient should be warned that dry sheen needs to be restored every 6 months. When filling cavities of II, III, IV classes, flosses are used to control the marginal fit of the seal in the gum area, as well as to control the contact point. Floss is introduced into the interdental space, without delay, but with great effort slides over the contact surface. It shouldn't tear or get stuck.

43. Microfilled and hybrid composites

Composites with small particles (micro-filled) are similar in properties to macro-filled ones, but due to a decrease in particle size, they have a higher degree of filling, are less susceptible to abrasion (about 50 microns per year) and are better polished. For filling in the area of the frontal group, Visio-Fill, Visar-Fill, Prisma-Fill (light-curing) are recommended, in the area of chewing teeth are used: P-10, Bis-Fil II (chemical curing), Estelux Post XR, Marathon, Ful-Fil , Bis-Fil I, Occlusin, Profil TLG, P-30, Sinter Fil (light cured).

In 1977, microfilled composites were created, which include particles of an inorganic filler 1000 times smaller than those of macrophiles, due to this, their specific surface area increases by 1000 times. Microphilic composites are easily polished compared to macrophiles, they are distinguished by high color fastness (light-curing), less abrasion, since they are not characterized by roughness. Nevertheless, they are inferior to conventional composites in terms of strength and hardness, have a higher coefficient of thermal expansion, significant shrinkage and water absorption. An indication for their use is the filling of carious cavities of the frontal group of teeth (III, V classes).

A variety of microfilled composites are inhomogeneously microfilled composites, which include fine particles of silicon dioxide and microfilled prepolymers. In the manufacture of these composites, prepolymerized particles (about 18–20 µm in size) are added to the bulk containing microfilled particles; thanks to this technique, saturation with the filler is more than 80% by weight.

Hybrid composite materials

The inorganic filler is a mixture of conventional large particles and microparticles. Contact with an etching agent on an adjacent tooth, if it is not isolated by a matrix, can lead to the development of caries.

Acid damage to the oral mucosa leads to burns. The etching solution must be removed, the mouth rinsed with an alkali solution (5% sodium bicarbonate solution) or water. With significant tissue damage, treatment is carried out with antiseptics, enzymes, keratoplastic preparations.

After etching, it is necessary to exclude contact of the etched enamel with the oral fluid (the patient should not spit, the use of a saliva ejector is mandatory), otherwise the microspaces are closed by saliva mucin, and the adhesion of the composites deteriorates sharply. If the enamel is contaminated with saliva or blood, the etching process must be repeated (cleaning etching - 10 s).

After washing, the cavity should be dried with an air jet, the enamel becomes matte.

44. Properties of composites

1. Technological properties:

1) the final form of chemically curing composites contains two composites (mixed before filling): "powder - liquid", "paste - paste";

2) after mixing, chemically cured composites acquire plasticity, which they retain for 1,5-2 minutes - working time;

3) the curing time for chemically cured is on average 5 minutes, for photopolymers - 20-40 s.

2. Functional properties:

1) all composites have sufficient adhesion, which depends on the etching, the type of bonds or adhesives used;

2) composites of chemical curing have the greatest shrinkage, mostly of the "powder-liquid" type;

3) compressive and shear strength is the highest for hybrid and macrofilled composites, less for microfilled ones;

4) water absorption is greatest in microfilled ones, which significantly reduces their strength, less in hybrids and macrophiles, since they contain less organic component and more filler;

5) the coefficient of thermal expansion is closest to solid tissues in macrofilled and hybrids due to the high content of the filler;

6) all composites have low thermal conductivity.

3. Biological requirements (properties). Toxicity is determined by the degree of polymerization, which is greater for photopolymers, and therefore they contain fewer low molecular weight substances and are less toxic.

4. Aesthetic properties. All chemically cured composites change color due to the oxidation of benzoyl peroxide, macrofilled - due to roughness.

The task of the dentist is not only to achieve an individual appearance, but also to provide for the variability of the color of natural teeth under any lighting conditions. The solution to this problem is possible if the doctor restores the crown of the tooth with materials that optically exactly imitate dental tissues:

1) enamel + surface enamel, enamel-dentine junction;

2) dentin + peripulpal dentin (does not imitate the pulp).

Finally, artificial dental tissues must be included in the restoration design within the topographical boundaries of natural dental tissues, such as:

1) the center (cavity) of the tooth;

2) dentin;

3) enamel.

To repeat the natural structure of the tooth is the essence of the biomimetic method of tooth restoration.

45. Mechanism of adhesion of composites to dentin

Pathophysiological features of dentin:

1) dentin consists of 50% inorganic matter (mainly hydroxyapatite), 30% organic (mainly collagen fibers) and 20% water;

2) the surface of the dentin is heterogeneous, it is penetrated by dentin tubules containing processes of odontoblasts and water.

Taking into account the above features, in order to obtain a strong bond between dentin and composite, it is necessary:

1) use hydrophilic low-viscosity adhesives;

2) remove the smear layer or impregnate it and stabilize it. In this regard, dentin adhesive systems can be divided into type II:

a) Type I - dissolving the smeared layer and decalcifying dentin;

b) Type II - preserving and including a smeared layer.

A technique for obtaining a connection between composites and dentin.

1. Conditioning - treatment of dentin with acid to dissolve the smear layer, demineralize the surface dentin, open the dentin tubules.

2. Priming - treatment of dentin with a primer, i.e. a solution of a low-viscosity hydrophilic monomer that penetrates into demineralized dentin, dentinal tubules, forming strands. As a result, a hybrid zone is formed.

3. Application of a hydrophobic adhesive (bond) that provides a bond (chemical) with the composite.

When using Type I dentin adhesive systems, an acid solution (conditioner) is used to remove the smear layer.

4. Insulation.

5. Conventional preparation of the cavity with an enamel bevel at an angle of 45°.

6. Medical treatment (70% alcohol, ether, 3% hydrogen peroxide are not used).

7. The imposition of therapeutic and insulating pads (with deep caries) and insulating - with an average. Pads containing eugenol or phenol inhibit the polymerization process.

8. Etching of enamel. The etching gel is applied to the beveled edge of the enamel for 30-60 seconds, then the cavity is washed and dried for the same time.

9. Mixing two-component bond 1:1, applying it to the etched enamel and gasket, spraying.

10. Mixing basic and catalytic paste 1:1 for 25s.

11. Filling the cavity. The time of use of the prepared material is from 1 to 1,5 minutes.

12. Final processing of the seal.

46. Polymerization of composites

The disadvantage of all composites is polymerization shrinkage, which is approximately 0,5 to 5% The reason for shrinkage is the decrease in the distance between the monomer molecules as the polymer chain is formed. The intermolecular distance before polymerization is about 3-4 angstroms, and after it 1,54.

The impetus for the polymerization reaction is given by heat, a chemical or photochemical reaction, as a result of which free radicals are formed. Polymerization occurs in three stages: start, propagation and end. The propagation phase continues until all free radicals have combined. During polymerization, shrinkage occurs and heat is released, as in any exothermic reaction.

Composite materials have shrinkage in the range of 0,5-5,68%, while shrinkage in fast-hardening plastics reaches 21%.

Polymerization shrinkage is most pronounced in chemically cured composites.

Dyract PSA One-Part Adhesive

The curing reaction initially occurs due to the light-initiated polymerization of the composite part of the monomer, and then the acid part of the monomer enters the reaction, leading to the release of fluorine and further cross-linking of the polymer.

Features:

1) reliable adhesion to enamel and dentine;

2) marginal fit, as in composites, but easier to achieve;

3) strength is greater than that of GIC, but less than that of composites;

4) shrinkage, as in composites;

5) aesthetics and surface properties close to composites;

6) prolonged release of fluorine.

Indications:

1) III and V classes of permanent teeth;

2) non-carious lesions;

3) all classes, according to Black, in milk teeth.

DyractAP

Features:

1) reduced particle size (up to 0,8 microns). This increased resistance to abrasion, increased strength, fluorine release, improved surface quality;

2) a new monomer has been introduced, strength has been increased;

3) improved initiator system, increased strength;

4) new adhesive systems Prime and Bond 2,0 or Prime and Bond 2,1 are applied.

Indications:

1) all classes, according to Black, in permanent teeth, cavities of classes I and II, not exceeding 2/3 of the intertubercular surface;

2) to imitate dentine ("sandwich technique");

3) non-carious lesions;

4) for filling milk teeth.

47. Requirements when working with composite material

The requirements are as follows.

1. Subject the light source to periodic inspection, as deterioration in the physical characteristics of the lamp will affect the properties of the composite. As a rule, the lamp has a light output indicator, if it is not there, you can apply a layer of filling material on the mixing pad with a layer of 3-4 mm and cure with light for 40 seconds. Then remove the layer of uncured material from below and determine the height of the fully cured mass. Typically, the power density of curing lamps is 75-100 W/cm².

2. Taking into account the limited penetrating power of light, the filling of the carious cavity and the polymerization of the seal should be incremental, i.e. layered, with a thickness of each layer no more than 3 mm, which contributes to a more complete polymerization and reduced shrinkage.

3. In the process of working with the material, it should be protected from extraneous light sources, especially from the light of the lamp of the dental unit, otherwise, premature curing of the material will occur.

4. Low-power lamps less than 75 W suggest a longer exposure and a reduction in the thickness of the layers to 1-2 mm. In this regard, the increase in temperature below the surface of the seal at a depth of 2-3 mm can reach from 1,5 to 12,3^оC and damage the pulp.

5. To compensate for shrinkage, a directional polymerization technique is used.

Thus, photopolymers have the following disadvantages: heterogeneity of polymerization, duration and complexity of filling, the possibility of thermal damage to the pulp, high cost, mainly due to the high cost of the lamp.

Most of the shortcomings of photopolymers are associated with the imperfection of the light source. The first photopolymers were cured with an ultraviolet emitter, later systems with longer wavelength light sources (blue light, wavelength 400-500 nm) were proposed, which are safe for the oral cavity, the curing time was reduced from 60-90 s to 20-40 s, the degree of polymerization with a material thickness of 2-2,5 mm. At present, the most promising light source is the argon laser, which can polymerize to a greater depth and width.

48. Mechanism of adhesion between composite layers

The construction of the restoration structure is based on gluing, which, according to its intended purpose, can be divided into gluing the restorative material with tooth tissues and gluing fragments of the restorative material (composite or compomer) together, i.e., a layered technique for building restorations.

The polymerization of chemical curing composites is directed towards the highest temperature, i.e., towards the pulp or the center of the filling, therefore chemical curing composites are applied parallel to the bottom of the cavity, since shrinkage is directed towards the pulp. Shrinkage of photopolymers is directed towards the light source.

I class. To ensure a good connection of the composite with the bottom and walls, it is applied in oblique layers approximately from the middle of the bottom to the edge of the cavity on the chewing surface. First of all, the deposited layer is illuminated through the corresponding wall (to compensate for polymerization shrinkage), and then it is irradiated perpendicular to the composite layer (to achieve the maximum degree of polymerization). The next layer is superimposed in a different direction and is also reflected first through the corresponding wall, and then perpendicular to the composite layer.

II class. When filling, the most difficult is the creation of contact points and good marginal adaptation in the gingival part. For this purpose, wedges, matrices, matrix holder are used. To stop the shrinkage, the gingival part of the filling can be made from a chemically cured composite, CRC, since its shrinkage is directed towards the pulp.

III class. Layers are superimposed on the vestibular or oral walls, followed by reflection through the corresponding wall of the tooth, on which the composite layer was applied.

The gingival part of the filling in III and IV classes polymerizes similarly to II.

V class. Initially, a gingival part is formed, the fillings of which are polymerized by directing the light guide from the gum at an angle of 45°. The shrinkage is directed towards the gingival wall of the cavity, resulting in a good marginal fit. Subsequent layers are polymerized by directing the light guide perpendicularly.

After polymerization of the last layer, a finishing treatment is carried out to remove the surface layer, which is easily damaged and permeable to dyes.

The strength of the GIC depends on the amount of powder (the more it is, the stronger the material), the degree of maturity, and the characteristics of the processing of the filler. For example, high-strength type II GRC (having inclusions of silver particles in crushed glass particles) and type III gasket cements have the highest strength.

GIC have low water absorption and solubility associated with the degree of maturity of the cement. GIC maturation, depending on the type of cement, occurs at different times.

49. Polycarboxylate cements

Powder: zinc oxide, magnesium oxide, aluminum oxide.

Liquid: 40% polyacrylic acid solution.

The cured material consists of zinc oxide particles bound in a gel-like zinc polyacrylate matrix. The calcium ions of the dentin combine with the carboxyl groups of the polyacrylic acid, and the zinc ions "crosslink" the molecules of the polyacrylic acid.

Properties: physical and chemical bond with hard tissues, slightly soluble in saliva (compared to CFC), does not irritate (liquid is a weak acid), but has low strength and poor aesthetics. Used for insulating gaskets, temporary fillings, fixation of crowns.

The ratio of liquid and powder is 1:2, the mixing time is 20-30 s, the finished mass stretches behind the spatula, forming teeth up to 1 mm, and shines.

Insulating and medical pads

Composite materials are toxic to the dental pulp, therefore, with medium and deep caries, therapeutic and insulating pads are needed. The use of IV and V generation dentin adhesives (which reliably isolate the pulp and compensate for the shrinkage of composites) makes it possible to do without insulating pads in case of medium caries, and in case of deep caries, therapeutic and insulating pads are applied only to the bottom of the cavity. The use of eugenol-containing cements is unacceptable, since eugenol inhibits polymerization. When filling canals with materials based on resorcinol-formalin mixture and eugenol, an insulating lining made of phosphate cement, glass ionomer or polycarboxylate cement is applied to the mouth of the canal.

Medical pads

With deep caries, the use of calcium-containing therapeutic pads is indicated. Calcium hydroxide, which is part of their composition, creates an alkaline pH level of 12-14, as a result of which it has an anti-inflammatory, bacteriostatic effect (pronounced dehydration) and an odontotropic effect - it stimulates the formation of replacement dentin.

Therapeutic pads are applied only to the bottom of the cavity in the projection of the pulp horns with a thin layer. Etching of enamel and dentine is carried out after the isolation of the medical lining with GIC (glass ionomer cement), since due to the high marginal permeability of the medical lining, an acid depot is created under it.

There are single-component medical pads of light (Basic-L) and chemical curing (Calcipulpa, Calcidont) and two-component chemical curing (Dycal, Recal, Calcimot, Live, Calcesil).

Insulating pads

As insulating gaskets can be used:

1) zinc phosphate cements;

2) polycarboxylate;

3) glass ionomer (GIC).

50. Glass ionomer cements

The priority of the invention of the JIC belongs to Wilson and Keith (1971).

Glass ionomer cements are materials based on polyacrylic (polyalkenic) acid and crushed alumino-fluorosilicate glass. Depending on the type of the original form, there are:

1) type "powder - liquid"

2) type "powder - distilled water"

Glass ionomer cements are classified according to their purpose.

I type. It is used for fixation of orthopedic and orthodontic constructions (Aquameron, Aquacem, Gemcem, Fuji I).

Type II - restorative cement for the restoration of defects in the hard tissues of the tooth:

1) type for cosmetic work. Works that require aesthetic restoration, with a slight occlusal load (Chemfill superivjr, Vitremer. Aqua Ionofill).

2) for work requiring increased strength of seals (Ketak-molar; Argion).

III type - laying cements (Bond applican, Gemline, Vitrcbond, Vivoglas, Miner, Bond fotak, Ionobond, Ketak bond, Time Line, Stion APH, Base Line, lonoseal).

Type IV - for root canal filling (Ketak endo applican, Stiodent).

Type V - sealants (Fuji III).

SIC properties.

1. Technological properties (uncured material). The mixing time is 10-20 s, after which the material acquires plasticity, which is maintained for 1,5-2 minutes.

2. Functional properties. Adhesion to enamel and dentin is of a chemical nature (A. Wilson, 1972) due to the combination of calcium ions of hard tooth tissues and carboxyl groups of polyacrylic acid. As a result of finishing - the surface is smooth, transparent, shiny. Under different lighting (direct, transmitted, side light), the restoration is monolithic, the border with dental tissues is not visible.

GIC for cosmetic work

The ratio of powder to liquid is from 2,2:1 to 3,0:1 (if the liquid is polyacrylic acid) and from 2,5:1 to 6,8:1 (for materials mixed with distilled water).

The CIC curing reaction can be represented as an ionic cross-link between polyacrylic acid chains.

GITs of increased strength (Argion, Ketak Molar)

An increase in strength is achieved by the introduction of an amalgam alloy powder, but the physical properties do not change much. A significant increase in strength and resistance to abrasion is achieved by introducing into the composition about 40% by weight of silver microparticles, which are baked into glass particles - "silver cermet".

51. Gasket cements

They are not transparent and not aesthetic, therefore they are covered with restorative materials. They quickly cure, becoming resistant to dissolution within 5 minutes, have chemical adhesion to enamel and dentin, which prevents marginal permeability, emit fluorine, and are radiopaque.

The ratio of powder and liquid is from 1,5:1 to 4,0:1,0; in a "sandwich" type structure, at least 3:1, since a larger amount of powder increases strength and reduces the curing time.

After 5 minutes, they acquire sufficient strength, resistance to dissolution, and can be etched with 37% phosphoric acid simultaneously with the enamel. Mixed manually or in capsules, injected with a spatula or syringe.

When filling several cavities, the CIC is inserted into one cavity and covered with another restorative material. If several cavities are filled at the same time, then to prevent overdrying, the GIC is insulated with varnish. The subsequent overlay of the composite should be layered, following the method of directed polymerization to prevent separation of the GIC from the dentin. The strength is sufficient to replace the dentine with subsequent coating with another restorative material.

Light-curing GICs contain 10% of a light-cured composite and harden under the action of a light activator in 20–40 s. The final curing time required for the formation of polyacrylic chains and the acquisition of final strength by cement is approximately 24 hours. GIC modified with photosensitive polymers are less sensitive to moisture and dissolution (in the experiment - after 10 minutes). The advantage of such cements is also a chemical bond with the composite. Steps for applying glass ionomer cement:

1) tooth cleaning;

2) isolation of the tooth.

Mixing of the components is carried out manually and using a capsule system, followed by the introduction of a spatula or syringe. The capsule mixing system followed by injection with a syringe makes it possible to reduce the level of porosity and evenly fill the cavity. Curing time: mixing time 10-20 s, initial curing 5-7 minutes, final curing after a few months. These properties cannot be changed without losing transparency. After the initial curing, the cement is isolated with a protective varnish based on BIS-GMA (it is better to use a bond from light-activated composites), and the final treatment is carried out after 24 hours, followed by re-insulation with varnish.

Physical properties: GICs of the group under consideration are not sufficiently resistant to occlusal loads, therefore their scope is limited to class III, V cavities, erosions, wedge-shaped defects, cement caries, fissure sealing, filling of milk teeth.

52. Compomers

The term "compomer" was derived from the two words "composite" and "ionomer".

The material combines the properties of composites and glass ionomers.

Adhesive bonding system, polymer matrix was taken from composites, chemical bond between glass particles (filler) and matrix, fluorine release from the mass, proximity of thermal expansion to tooth tissues were taken from CIC.

Composition of composites (using Dyract as an example):

1) monomer (qualitatively new);

2) composite resin (BIS-GMA) and polyacrylic acid;

3) special type powder;

4) liquid (from 1,67 to 5,68%) and least in light-cured composites (0,5-0,7%).

Chemically activated composites consist of two pastes or liquid and powder. The composition of these components includes an initiator system of benzoyl peroxide and amine.

When kneading the base paste containing amine and catalytic components, free radicals are formed that trigger polymerization.

The advantage of this type of polymerization is a uniform polymerization regardless of the depth of the cavity and the thickness of the filling, as well as a short-term heat release.

Disadvantages: possible errors during mixing (incorrect ratio of components), insignificant working time for filling modeling, impossibility of layer-by-layer application, darkening of the filling due to oxidation of the residue of the amine compound.

As a polymerization initiator in light-polymerizable composites, a light-sensitive substance is used, for example, campferoquinone, which, under the influence of light with a wavelength in the range of 400-500 nm, is cleaved to form free radicals.

Light-activated materials do not require mixing, therefore they do not have air porosity inherent in two-component chemically cured composites, i.e. they are more homogeneous.

Possible layer-by-layer applications to a large extent allow you to more accurately select the color of the seal. The absence of a tertiary amine will give the material color stability. Thus, photohardening composites are more aesthetically pleasing.

However, it should be noted that the degree of polymerization is not uniform, polymerization shrinkage is directed towards the source of polymerization. The concentration of underpolymerized groups is the lower, the closer the light source.

Curing time - 5-6 min. Final polymerization after 24 hours, therefore, after curing, it is necessary to protect with a varnish (supplied), for example, Ketak Glaze. Final processing - after 24 hours.

The presented description is indicative, it cannot take into account the peculiarities of the use of various representatives of a large group of glass-filled cements, therefore, in all cases, their use must comply with the manufacturer's instructions.

53. Method of working with composite materials of chemical curing (on the example of microfilament composite "Degufil")

Before working with these composite materials, it is necessary to determine the indications for its use (depending on the classification of cavities, according to Black), for the material in question - classes III, V, it is possible to fill cavities of other classes when preparing a tooth for fixed prosthetics.

1. Tooth cleaning (no fluoride-containing pastes are used).

2. Color selection is made by comparison with the scale in daylight; the tooth must be cleaned.

Total etch technique: acid gel is applied first to the enamel and then to the dentin. Etching time for enamel is 15-60 s, and for dentine - 10-15 s. Washing 20-30 s. Drying - 10 s.

Advantages:

1) saving time - the processing of tooth tissues is carried out in one stage;

2) the lubricated layer and its plugs are completely removed, tubules open, relative sterility is achieved;

3) the permeability of dentin is sufficient for the formation of a hybrid zone.

Disadvantages:

1) when the etched dentin is contaminated, the infection penetrates into the pulp;

2) with a high degree of shrinkage of the composite, hyperesthesia is possible.

Prior to etching, dentine contains 50% hydroxyapatite, 30% collagen and 20% water. After etching - 30% collagen and 70% water. During the priming process, the water is replaced by the adhesive and a hybrid zone is formed. This phenomenon is possible only if the collagen fibers remain moist and do not collapse, therefore water and air jets should be directed to the enamel, only reflected ones to the dentin. After drying, the enamel is matte, and the dentin is slightly moistened, sparkling (the so-called wet bonding concept). When the dentin is dried out, collagen fibers fall off - the "spaghetti effect", which prevents the penetration of the primer and the formation of a hybrid zone.

The next step after conditioning is the application of a primer. The primer contains a low-viscosity hydrophilic monomer (eg, CHEMA - hydroxyethyl methacrylate), penetrating into wet dentin; glutaraldehyde (chemical bond with collagen, denatures, fixes, disinfects protein); alcohol or acetone (reduce the surface tension of water, contributing to the deep penetration of the monomer). Priming time - 30 s or more. As a result of priming, a hybrid zone is formed - a zone of monomer penetration into demineralized dentin and tubules, the penetration depth is limited by the odontoblast process.

54. Method of application of light-cured composite material

I stage. Cleaning the surface of the teeth from plaque, tartar.

II stage. Material color selection.

III stage. Insulation.

IV stage. Preparation of a carious cavity. When using a composite material with enamel adhesives, the preparation is carried out traditionally: a right angle between the bottom and the walls; in classes II and IV, an additional platform is required. It is obligatory to bevel the edge of the enamel - at an angle of 45° or more to increase the surface area of contact between the enamel and the composite. With class V - flame-shaped bevel. If composites with IV, V generation enamel-dentin systems are used, traditional principles of preparation can be abandoned. Enamel bevel is carried out in cavities V and IV; III class - according to aesthetic indications.

V stage. Medical treatment and drying.

VI stage. The imposition of insulating and medical pads

VII stage. Etching, washing, drying.

Solitare is a modification of the cladding material Artglass "Heraeus kulze" and therefore can be included in the group of materials based on polymer glass.

Composition: 1) organic matrix: high molecular weight esters of methacrylic acid, achieving an amorphous highly wettable structure, similar to organic glass. Organic glass is bonded to a silane-treated inorganic filler;

2) inorganic filler:

a) polyglobular particles of silicon dioxide in size from 2 to 20 microns;

b) fluorine glass, particle size - from 0,8 to 1 micron;

c) fluorine-containing glass based on barium aluminosilicate, the average particle size is less than 1 micron;

3) rheologically active silicic acid.

The total amount of inorganic filler is not less than 90%.

The material is recommended for filling I and II classes of carious cavities, according to Black.

It is applied with adhesive system of IV generation "Solid Bond". Shrinkage during polymerization is 1,5-1,8%, the material is resistant to chewing load, dissolution, well polished, color stable.

Used in a simplified way:

1) used with metal matrices and wooden wedges;

2) is applied in layers parallel to the bottom, polymerized with light for 40 s directed perpendicular to the filling, the thickness of the layers is 2 mm or more (except for the first layer).

This material can serve as an alternative to amalgam and can be used for filling the chewing group of teeth, along with fine hybrid composites.

55. Principles of biomimetic construction of teeth with restorative materials

A natural tooth is a translucent optical body, consisting of two optically different tissues: more transparent and light enamel and less transparent (opaque - opaque) and dark dentin.

The ratio of enamel and dentin creates differences in the appearance of different parts of the crown of the tooth, such as:

1) the cervical part of the crown, where a thin plate of enamel is combined with a large mass of dentin;

2) the middle part of the crown, where the thickness of the enamel increases and the amount of dentin decreases significantly;

3) the edges of the crown, where a thin plate of dentin is combined with two plates of enamel.

The combination of enamel and dentin also creates differences in the appearance of different teeth in one person: light incisors, in which enamel is combined with a small amount of dentin; more yellow fangs - enamel is combined with a large amount of dentin; darker molars - the amount of dentin is even more increased compared to enamel.

The crown of the tooth, due to translucency, has color variability under different lighting conditions (cold blue light prevails in the morning, warm red in the evening; the light intensity changes). The range of variability of the teeth depends on the individual transparency of the crown. Thus, more transparent teeth have greater variability, while less transparent teeth have the opposite.

According to the degree of transparency, teeth can be divided into three conditional groups:

1) absolutely opaque "deaf" teeth, when there is no transparent cutting edge, due to the peculiarities of the individual structure or abrasion - these are yellow teeth. The range of color changes of the vestibular surface is low and is detected when the tooth is translucent from the oral side;

2) transparent teeth, when only the cutting edge is transparent. As a rule, these are teeth of yellow-gray shades, the range of color changes of the vestibular surface is not significant;

3) very transparent teeth, when the transparent cutting edge occupies 1/3 or 1/4 and the contact surfaces are also transparent.

Mistakes and complications in the use of composite materials, compomers, GIC

At the stage of tooth cleaning and color determination: before determining the color of the teeth and preparing the carious cavity, it is necessary to clean the tooth from plaque and remove the pellicle layer. For this, a nylon brush and a fluorine-free paste are used, otherwise the color determination will not be carried out correctly. It is also necessary to use the standard rules for determining the color of the teeth (shading scale, moistened tooth, natural light). In the case of aesthetic restorations, it is important to determine the individual transparency of the teeth.

56. The mechanism of adhesion of composites with enamel

Adhesives and bonds are used to improve the micromechanical adhesion of composites to dental tissues, compensate for polymerization shrinkage, and reduce marginal permeability.

Enamel mainly consists of inorganic matter - 86%, a small amount of water - 12% and an organic component - 2% (by volume). Thanks to this composition, the enamel can be dried, so the hydrophobic organic component of the composite is the BIS-GMA monomer, which has good adhesion to the enamel. Thus, hydrophobic viscous adhesives (bonds) are used in the enamel area, the main component of which is the BIS-GMA monomer.

Method for obtaining a bond between composites and enamel

Stage I - forming a bevel at 45° or more. The bevel is necessary to increase the active surface of the bond between the enamel and the composite.

II stage - etching of enamel with acid. 30-40% orthophosphoric acid is used in the form of a liquid or gel, and the gel is preferable, since it is clearly visible and does not spread. The etching period for enamel is from 15 s to 1 min.

As a result of pickling:

1) organic plaque is removed from the enamel;

2) enamel microroughness is formed due to the dissolution of enamel prisms to a depth of approximately 40 μm, which significantly increases the surface area of the adhesion of the composite and enamel. After applying the bond, its molecules penetrate into microspaces. The adhesive strength of the composite to the etched enamel is 75% higher than that of the unetched one;

3) etching allows to reduce the marginal permeability at the "enamel-composite" interface.

Stage III - the use of enamel (hydrophobic) bonds based on the organic matrix of the composite (BIS-GMA monomer), which penetrate into the microspaces of the etched enamel. And after polymerization, processes are formed that provide micromechanical adhesion of the enamel to the bond.

The identification of the patient's teeth is carried out immediately after cleaning with a nylon brush and professional toothpaste (not containing fluoride) in natural light, the surface of the teeth must be moist. The assessment of the result of the restoration is carried out no earlier than 2 hours after completion of the work, preferably after 1-7 days, then a decision is made on the need for correction. A properly executed restoration looks darker and more transparent immediately after completion of the work due to the drying of the enamel, which becomes lighter and less transparent. After water absorption, the color and transparency of artificial and natural dental tissues are the same.

IV stage - application of the adhesive system.

V stage - filling.

Stage VI - final processing.

Authors: Kapustin K.M., Orlov D.N.

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