Tooth decay

Dental caries is an acute or chronic pathological process that manifests itself as a change in color, demineralization and destruction of hard dental tissues and occurs with the active participation of microorganisms.

Over the centuries-long history of the specialty, more than 414 theories, views, and concepts of the disease have been proposed. In 1898, Miller presented the generally accepted and confirmed by many scientists chemical-parasitic theory of caries development. The essence of the theory is that oral microorganisms that cause dental caries, in the presence of special low-molecular carbohydrates, produce organic acids. With their prolonged effect on tooth enamel, its demineralization and the formation of a carious cavity occur. At the same time, there are secondary factors that cause dental caries. These include the rate of secretion and composition of oral fluid, pH, buffer capacity of saliva, frequency and duration of carbohydrate action, occlusion disorders, and pathology of tooth formation.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ]

What causes dental caries?

One of the leading factors that causes dental caries is dental plaque. Dental plaque is a structured viscous deposit on the tooth, consisting of components of saliva, bacteria, bacterial metabolic products and food debris.

The process begins with the formation of supragingival plaque on hard-to-clean areas of the teeth (fissures, approximal surfaces, cervical areas of the crown). Dental plaque is formed in several stages. Initially, an unstructured film 0.1 - 1 μm thick, consisting of salivary proteins, is formed on the tooth surface. It includes acidic, proline-rich proteins, glycoproteins, serum proteins, enzymes, immunoglobulins. These inclusions are linked to each other electrostatically. The acellular film acts as a semi-impermeable membrane that controls the exchange processes between the oral environment, plaque and the tooth.

At the second stage, gram-positive cocci (Streptococcus sanguis), actinomycetes, veillonella and filaments attach to the formed film. The plaque increases in volume by division and further accumulation of bacteria. Mature plaque consists of a dense layer of bacteria by 60-70% of its volume. It is not washed off by saliva and is resistant to rinsing the mouth. The composition of the plaque matrix depends on the composition of saliva, the nature of nutrition and the products of bacterial activity. The formed microbial plaque is a key factor that causes dental caries. The leading role in the process of caries formation is played by Str. mutans, which is found in the microbial plaque and has significant productivity in metabolism. In the presence of sugar, Str. mutans, using glucosyl transferases, ensures tight adhesion of microorganisms to the tooth surface. Due to anaerobic glycolysis, streptococci form organic acids (lactate, pyruvate), which, upon contact with tooth enamel, demineralize hard tissues. Str. mutans, along with the formation of organic acids, is resistant to an acidic environment. It can exist at an acidity below 5.5. Under these conditions, other microorganisms die. Other microorganisms of the oral cavity that play a role in the pathogenesis of caries are lactobacilli and actinomycetes. Lactobacilli exhibit metabolic activity in an acidic environment. Actinomycetes slightly increase the acidity of dental plaque, but they contribute to the development of dental caries. In particular, Orlander and Blayner in 1954, in experiments on animals proved that when they are kept in sterile conditions and fed a cariogenic diet, dental caries does not occur. As soon as Str. mutans, caries developed in animals. Cariogenic infection can also be transmitted from one animal to another. Thus, the possibility of caries infection in humans was demonstrated, in particular from mother to infant through a pacifier.

The quality of nutrition and frequency of consumption of carbohydrates (sucrose, glucose, fructose, lactose and starch), which form a nutrient medium for microorganisms, are the main factors that cause dental caries. Oral fluid is of great importance in the oral cavity protection system. It contains 0.58% of mineral components (calcium, phosphorus, fluorine, etc.). pH is 6.8 fi.4. Up to 1.5-2 liters are excreted per day. The functions of oral fluid are numerous. These include: rinsing the oral cavity organs, neutralizing acids (bicarbonates, phosphates, proteins), remineralizing enamel (fluorides, phosphates, calcium), creating a protective shell on the tooth surface (glycoprotein, mucin), antibacterial effect (antibodies, lysozyme, lactoferrin, lactoperoxidase), participation in digestion (amylases, proteases). Changes in the volume of oral secretion (hyposalivation) and its biochemical properties contribute to the development of caries.

Dental caries in the spot stage (initial caries)

There are no complaints of pain. Cosmetic defect: white or pigmented spot. Possible feeling of soreness.

History: the spot appeared recently (days, weeks, pigmented - months). The size and intensity of the spot color increase. The white spot may become pigmented.

Examination reveals a whitish enamel area or enamel pigmentation. White is more typical for children's teeth, while pigmented spots are more typical for adults. Localization: cervical areas of the tooth, pits, fissures, proximal surfaces. Strict symmetry of lesions is not typical; multiple dental caries is possible. Drying increases the matte and whiteness of the spot.

Objective data. Probing: the enamel surface is clinically unchanged, the probe does not linger, glides over the surface; there is no roughness. No pain is noted. Thermometry: physiological sensitivity is unchanged (the tooth does not react to cold). Percussion - the reaction is negative. The affected area of enamel is stained with methylene blue. Transillumination reveals an area of luminescence extinction. Electrical excitability of the tooth is within normal limits (2-5 μA). There are no changes in hard tissues and periodontium on the radiograph. Differential diagnostics are carried out with non-carious lesions of the enamel.

[ 8 ], [ 9 ], [ 10 ]

What types of dental caries are there?

More than 20 systems have been proposed for recording the condition of teeth in clinical documents. In our country, the system of digital designation of teeth of the upper and lower jaws proposed by Zigmonoidi in 1876 is used.

In 1970, in Budapest, the International Dental Federation (FDI), the International Organization for Standardization (ISO) and the World Health Organization (WHO) approved an international system of tooth designation, where each half of the upper and lower jaws is designated by a number.

The tooth number is designated from the measuring incisor to the third molar by numbers from 1 to 8, respectively.

In the United States, the American Dental Association's universal numerical system has been adopted.

Permanent bite:

• 1-8 9-16
• 32-25 24-17

Temporary bite:

• ABCDE FYHI
• TSRQP ONMLK

ISO suggests that the name of the tooth surface accepted in the clinic be designated by letters:

• occlusal - O (O),
• mesial - M (M),
• distal - D (D),
• vestibular (labial or buccal) - B (V),
• lingual - L,
• radicular (root) - P (G).

The classification of the carious process can be presented according to the following features.

Topographic:

• dental caries in the spot stage;
• superficial dental caries;
• moderate dental caries;
• deep dental caries.

Anatomical:

• enamel caries;
• dentin caries;
• cement caries.

By localization:

• fissure caries of teeth;
• approximal dental caries;
• cervical dental caries.

According to Black (1914), five classes are distinguished based on the localization of carious lesions.

• Class 1 - cavities located in the pits and fissures of the molars and premolars, the lingual surface of the upper incisors and the vestibular and lingual grooves of the molars.
• Class 2 - cavities on the approximal (contact) surfaces of molars and premolars.
• Class 3 - cavities on the approximal surfaces of incisors and canines without damage to the cutting edges.
• Class 4 - cavities on the approximal surfaces of incisors and canines with damage to the cutting edge.
• Class 5 - cavities in the cervical region on the vestibular and lingual surfaces.

American dentists also distinguish a 6th class.

Class 6 - cavities on the cutting edge of incisors and on the tops of tubercles.

By duration of the course:

• rapidly progressing dental caries;
• slow progressing dental caries;
• stabilized dental caries.

By intensity of caries development:

• compensated dental caries;
• subcompensated dental caries;
• decompensated dental caries (for children).

A number of authors have proposed classifications that take into account the above properties of the carious process. Thus, E.V. Borovsky and P.A. Leis (1979) proposed the following classification.

Clinical form:

• a) spot stage (carious demineralization);
• b) progressive (white and light spots);
• c) intermittent (brown spots);
• d) suspended (dark brown spots).

Carious defect (disintegration):

• enamel (superficial dental caries);
• dentin;
• moderate dental caries;
• deep dental caries;
• cement.

By localization:

• fissure caries dental caries;
• caries of the cervical region.

Downstream:

• rapidly progressing caries dental caries;
• slow-moving caries dental caries;
• stabilized process.

By intensity of damage:

• isolated lesions;
• multiple lesions;
• systemic lesions.

Tooth decay

Dental caries is characterized by toothaches that are strictly causal in nature and disappear immediately after the irritating factor is eliminated. The presence of a defect in the hard tissues of the tooth.

History. Dynamics of sensations: in the early stages - a feeling of soreness, then - pain from sweets, then - pain from thermal and mechanical irritants. The tooth defect appears after eruption (the tooth erupts intact).

Examination. Localization outside immune zones (gingival, proximal surfaces, pit and fissure areas). There is no strict symmetry of lesions. Single defects of individual teeth or multiple dental caries are possible. During examination, a spot or cavity is determined.

Objective data. Roughness on probing of the cavity bottom and walls. Percussion is painless. Electrical excitability of the pulp is within the limits of physiological sensitivity (2-10 μA). There are no changes in the periodontal space on the radiograph.

[ 11 ], [ 12 ]

Superficial dental caries

Complaints: pain from chemical irritants (from sweets). A cosmetic defect is determined in the form of a shallow cavity, color disturbance. Roughness of the enamel is detected.

History: the sensations appeared recently (weeks). Previously, there was a change in the color of the enamel in a separate area of the tooth. When pigmentation appears in the changed area, the pain from sweets may disappear.

Inspection: defect within the enamel - walls are whitish or pigmented. Localization - areas of low enamel resistance (cervical, proximal areas, pits, fissures).

Objective data. Probing reveals surface roughness. No pain. Thermometry and percussion are painless. The enamel around the defect is stained with methylene blue. Transillumination reveals extinction of the glow. Electrical excitability of the pulp is within normal limits (2-5 μA). There are no changes in the periodontal gap on the radiograph.

Probing provides additional information. In case of caries and acid necrosis, the surface is rough, the probe tip is retained in microdefects. In case of hypoplasia, fluorosis, erosion, wedge-shaped defect, the probe tip slides along the surface, no roughness is detected, the defect surface is smooth and shiny.

Moderate acute dental caries

Complaints of pain from chemical, thermal and mechanical effects, which disappears immediately after the irritant is removed. The presence of a cavity, food getting stuck.

History: The cavity may exist for several weeks or months. Previously, there was a change in the color of the enamel in a separate area of the tooth, roughness of the enamel, pain from sweets.

Examination reveals a cavity within the mantle dentin (medium depth), the dentin is light, without pigmentation. Localization is a favorite for caries (cervical area, proximal, occlusal surfaces, fissures, pits). Both single and multiple lesions are possible.

Objective data. Probing reveals roughness of the cavity bottom and walls, pain in the enamel-dentin junction area. Preparation of this area with a bur causes pain. Thermometry is painful: a directed stream of coolant provokes a short-term pain reaction. Percussion is painless. The enamel around the defect is stained with methylene blue. Electrical excitability of the pulp is unchanged (2-5 μA). There are no changes in the periodontal gap on the radiograph, an area of enlightenment is determined in the area of the carious cavity.

Moderate chronic dental caries

Complaints about the presence of a cavity (food getting stuck). The bottom and walls of the cavity are pigmented. Pain is absent or strictly causal (from cold), of low intensity.

History: the cavity may exist for several weeks or months. Previously, there was a change in the color of the enamel in a separate area of the tooth, roughness of the enamel. When pigmentation appeared in the changed area, the pain could disappear.

Inspection: the cavity is located within the mantle dentin (medium depth and size), the bottom and walls are pigmented. Localization is a favorite for caries (cervical area, proximal, occlusal surfaces). Symmetrical lesions are possible, but more often isolated.

Objective data. Probing reveals the roughness of the defect surface, probing can be painless or slightly sensitive in the area of the enamel-dentine junction. Preparation with an EDS bur is painful. Thermometry: a directed stream of coolant can cause a short-term pain reaction of low intensity. Percussion is painless. The enamel around the defect is not stained with methylene blue. Electrical excitability of the pulp is preserved. There are no changes in the periodontium on the radiograph, an area of enlightenment is detected in the area of the carious cavity.

[ 13 ], [ 14 ], [ 15 ], [ 16 ]

Deep acute dental caries

Complaints: acute pain from chemical, thermal and mechanical irritants, disappears immediately after the causative factor is eliminated. Possible tooth color change, crown defect, significant cavity size, food getting stuck.

The anamnesis includes pain from chemical irritants (sweets), the presence of a small cavity that gradually increased in size.

Examination reveals a deep carious cavity (of considerable size). The entrance opening is smaller than the width of the cavity, which is easily determined by probing. The enamel/dentin on the walls of the cavity may be light or chalky.

Objective data. Probing the bottom of the carious cavity is painful, softened dentin is pliable and is removed in layers. Thermal stimuli cause an intense but short-term pain reaction. Percussion of the tooth is painless. Electrical excitability of the pulp is within normal limits or slightly reduced (up to 10-12 μA). The radiograph shows a clearing area in the area of the carious cavity. There is no communication with the pulp chamber. There are no changes in the periodontium on the radiograph.

Deep chronic dental caries

Complaints about the causal pain are weakly expressed or may be absent. The presence of a cavity where food gets in and a change in the color of the tooth are of concern.

History: pain from chemical, thermal, mechanical irritants - strictly causal, short-term. In chronic course - symptoms are weakly expressed, periodic.

Upon examination, a carious cavity of considerable depth is determined, extending into the peripulpar dentin. A wide entrance opening is characteristic. The bottom and walls of the cavity are covered with pigmented dentin.

Objective data. When probing, there is no pain or it is weakly expressed in the area of the cavity bottom. Dentin is dense. There is no communication with the pulp. Thermometry is painless or weakly sensitive. Electrical excitability of the pulp is sometimes slightly reduced (10-12 μA). On the radiograph, the size of the carious cavity can be determined by the area of enlightenment. No changes in the periodontium are detected.

[ 17 ], [ 18 ], [ 19 ], [ 20 ]

Proximal dental caries

Complaints: food getting stuck between teeth is typical. Discoloration of the proximal part of the tooth. Pain from cold is possible.

The anamnesis provides scant information.

Examination, cavity is not determined. Discolored areas of enamel may be detected: chalky or pigmented

Objective data. Conventional probing of accessible tooth surfaces does not reveal cavities. Careful probing of the proximal area with a sharp instrument reveals roughness - the tip of the probe is retained in dentin. Rinsing the mouth with cold water may not cause pain. A directed stream of coolant provokes a short-term attack of pain. Percussion of the tooth is painless. Transillumination reveals an area of luminescence extinction in the proximal section. Electrical excitability of the tooth is within normal limits or slightly reduced (2-12 μA). X-ray diagnostics is of great importance: an X-ray image reveals an area of enlightenment in the area of the carious cavity.

Cementum caries

The initial stage of caries is characterized by softening of the cement. The defect is not detected, but the surface is characterized by a change in color: it becomes lighter or, conversely, pigmented, acquiring a light brown, reddish tint. Susceptibility to probing is determined. The appearance of a carious cavity is accompanied by destruction of dentin. As a result, the tip of the probe easily immerses into the root tissue. Thermometry and probing become painful, which corresponds to the clinical picture of dentin caries (medium or deep).

Cement caries can spread around the tooth circumference, circularly, towards the root apex or, conversely, towards the enamel-dentin junction. The development of a defect on the proximal surface can proceed asymptomatically until pulpitis occurs.

Removal of dental plaque facilitates visual detection of hidden cement lesions. Use of a sharp probe allows determination of dentin softening and the level of tactile sensitivity.

Radiographic examination - to diagnose proximal dental caries.

The development of caries is possible under an artificial crown. A lesion limited to enamel is rare, if the tooth has been under the artificial crown for a short period of time. If the period is longer, carious damage to dentin is twice as common. The development of cement caries also depends on the period of use of the artificial crown. Combined damage to the crown and root of the tooth is directly related to the duration of wearing the structure. The number of carious cavities in the gingival area increases significantly, and circular dental caries is found in older patients.

Destruction of the tooth crown horizontally, without a clearly expressed carious cavity, is recorded when the tooth has been under an artificial crown for a long time. A slit-shaped defect in the gingival area occurs in every fourth case. With an increase in the period of wearing the crown, the incidence of gingival caries increases. Violation of the marginal seal of the filling, the development of secondary caries occurs regardless of the duration of the tooth being under the artificial crown.

[ 21 ], [ 22 ], [ 23 ]

How to recognize dental caries?

Diagnosis of dental caries covered with an artificial crown requires careful probing of the tooth neck. The reaction to thermometry is carried out using a coolant with a directed stream (Coolan). Diagnosis is significantly facilitated after removing the artificial crown.

A thorough examination reveals the loss of the natural shine of the affected area of enamel. It becomes matte, and later, when it reaches the chronic stage with the deposition of melanin pigment and other dyes, it acquires a brown or even black color. The patient does not react to the effects of temperature stimuli. Percussion of this tooth is painless. Electroodontometry diagnostics indicates the presence of indicators equal to 3-6 μA, which corresponds to the norm.

On an X-ray, especially on the approximal surfaces of the teeth, it is possible to identify foci of demineralization, determine the affected area, the further course and results of remineralizing therapy.

In clinical practice, basic and additional methods of caries diagnostics are used; the basic methods include:

1. Stomatoscopy. Irradiation of teeth with an ultraviolet lamp. In the absence of caries, the tooth enamel will fluoresce with a yellowish light, and in the case of damage to the tooth structure (demineralization), a decrease in fluorescence will be noted.
2. Transillumination method. The method involves shining a halogen lamp through the tooth tissues to cure composite materials or a special lamp with fiber optics. The damage to the tooth structure will be noted as darkening participants. The method is used to detect secondary caries around the filling material, cracks in the tooth enamel, and to control the completeness of the removal of altered dentin when treating a carious cavity.
3. Vital staining. The method is based on the fact of increasing the permeability of the enamel barrier with dyes and the zone of demineralization or enamel etching with acid. A tooth cleaned of plaque and dried is stained for 3 minutes with tampons with a 2% aqueous solution of methylene blue. Then the dye is washed off with water and a stained etched area of enamel remains. The color intensity has a range from pale blue to bright blue with a color intensity from 0 to 100%, and in relative numbers from 0 to 10 or 12 depending on the difference in scales. Control is carried out after 24 hours, normal enamel is restored by this time and is not stained or, in the case of a change in acid resistance, remains stained for several more days. The duration of color retention can be used to judge the state of enamel demineralization.
4. Colorimetric test. The method involves sequentially rinsing the oral cavity with 0.1% glucose and 0.15% methylene red solution. In areas of enamel where the pH changes to the acidic side at 4.4-6.0 and below, the color changes from red to yellow. The caries detection rate is 74.8% (Hardwick).
5. Reflection. Detection of the carious process in the cervical area of the tooth by reflected light from the dental unit's lighting lamp.
6. The KAVO Diagnodent device, the laser diode of the device creates pulsed light waves that hit the surface of the tooth. As soon as the changed dental tissue is excited by this light, it begins to fluoresce with light waves of a different length. The length of the reflected waves is analyzed by the device. The level of tissue changes is reflected on the display of the device in the form of digital indicators or an audio signal. The device allows you to identify hard-to-reach areas of demineralization, fissure caries of teeth of the approximal surfaces or changed tissues during the treatment of the carious cavity. The operation of the device does not cause any unpleasant sensations in the patient.

Examination of dental patients allows us to assess the patient's predisposition to the cariogenic process. The predisposition of teeth to carious destruction is characterized by the following signs: caries of the front row teeth, rapid loss of fillings and the appearance of new carious cavities within one year after sanitation, the presence of several carious cavities on one tooth, the presence of depulped teeth and a large amount of plaque on the teeth.