Why classify caries? This is only at first glance a simple disease known to everyone. For dentists, there is a distinction between its various types, and each of them requires its own special approach to treatment.
Caries can be different
Caries is the most common disease of the oral cavity, developing in different parts of the teeth, the clinical picture of the process may also differ. For convenience in treatment, the correct choice of tooth preparation and the material used for filling, it is customary to classify the types of caries. This is how classes are distinguished according to Black, according to the depth of the lesion, according to the degree of activity of the destruction process, according to the presence of complications, according to the clinical nature and localization of the lesion.
The classification proposed back in 1986 by the American dentist J. Black is especially popular. Its purpose was to systematize the principles of treatment for various types of carious lesions of the tooth.
Black classes
Black identified five classes according to localization on the surface, that is, depending on where exactly thecavity:
- Localization in fissures (depressions and crevices in the enamel of the chewing surface), pits of molars and premolars (large and small molars), canines and incisors.
- Two or more surfaces are affected - the medial and distal (caries on the front teeth) or occlusal (cutting and chewing surface) of molars and premolars are captured.
- The development of the disease on the medial and distal parts of the canines and incisors.
- Localization is the same as Grade 3, plus the coronal or incisal angle is captured.
- The cavity occupies the cervical region of any group of teeth.
Black's classes systematize all possible options for the development of caries, for each of them a separate treatment is provided, a method for preparing a diseased tooth and installing a filling.
Black First Class
The carious cavity located in this way increases the risk of breaking the edge of the filling due to the high pressure on it when chewing. When preparing a tooth, measures are taken to exclude this possibility. This happens by reducing the bevel of the enamel and applying a thicker layer of filling material. When using a chemically cured composite, it is applied parallel to the bottom of the carious cavity, since shrinkage will be directed towards the pulp. If a light-curing material is used, it is laid in oblique layers. Shrinkage in this case will be directed towards the source of polymerization. Layers should lie from the middle of the bottom to the edge of the cavity, reflectionoccurs through the side walls, and after - perpendicular to the chewing surface. As a result, a tight fit of the filling in the cavity is achieved.
First class cavity filling steps
Such actions must be taken by the dentist to cure class 1 according to Black:
- pain relief (use anesthetic gel or lidocaine spray),
- prepare the tooth (preparation involves drilling the area affected by caries deep into the hard tissue),
- if necessary, apply an insulating gasket (to prevent the composite from affecting the pulp and irritating it),
- etch and wash off acids, dry cavity,
- isolate from saliva,
- apply primer if necessary (to prepare dentin),
- apply adhesive (bonding element between composite and dental tissue or primer),
- layer by layer apply material, cure it,
- adjust to shape, finish and polish,
- make a glow (final curing).
Black Second Class
Class 2 according to Black, which has its own difficulties, involves two main tasks in its treatment - to create a strong contact between the teeth and to ensure a snug fit of the composite to the edge of the main cavity. Often the filling process is complicated by the appearance of an overhanging edge of the filling, the lack of contact between the teeth or the material with the carious cavity. To prevent this, thin matrices are used, a shift is carried outtooth (within possible limits) using wooden wedges. A matrix is introduced into the interdental space and fixed with a wedge, then moistened with water. The wedge swells and pushes the tooth back. This method during filling avoids overhanging the edge of the filling, which in turn can cause inflammation of the gums. The tight fit of the material to the cavity ensures the use of an adhesive - a binder, since the composite itself can only be firmly connected to enamel, but not to dentin.
Stages of filling cavities of the second class
Black's classes in treatment have similar points, but each of them requires special nuances of filling. Here are the steps for the second grade:
- pain relief,
- preparation,
- if necessary, gum correction,
- installation of the matrix with the introduction of a wooden wedge or holder,
- if necessary pushing teeth apart,
- applying an insulating pad (if necessary),
- carrying out the procedure of etching, washing off the acid and dryingcavities,
- tooth isolation from saliva,
- applying primer and adhesive,
- if necessary - restoration of the enamel edge (if there is none),
- composite layering,
- extraction of matrix and wedge,
- interdental contact control,
- correction, polishing,
- finishing reflections.
Third and fourth grades
Here the main role is played byselection of the color of the filling material, because in this case caries is localized on the front teeth. Due to the different transparency coefficient of dentin and enamel, it is necessary to use a composite of two different colors during treatment. This is necessary so that the tooth appears homogeneous, and the filling does not look like a patch. To create the most natural effect, white shades of the material are used to imitate dentin, and almost transparent to recreate enamel. To make the transition invisible, the enamel bevel overlaps by 2-3 mm. It is important that such fine work is done by a good dentist who can correctly determine the transparency of the tooth. There are three degrees of it: opaque (usually yellowish, even the cutting edge is opaque), transparent (yellow-gray shades, the cutting edge is transparent), very transparent (grayish tint, the transparent edge occupies a third of the tooth.
Stages of filling cavities of grades 3 and 4
To fill the third and fourth classes of Black cavities, the dentist must do the following:
- clean the surface from plaque,
- determine the shade of the tooth,
- anesthetize,
- prepare the tooth, free from affected tissues,
- install retraction cords or matrices when needed (gingival margin affected),
- apply insulating pad,
- if necessary, restore the contours of the teeth,
- wash off the acid and dry the cavity,
- isolate saliva,
- apply primer (optional) andadhesive,
- apply layers of blocking material,
- removing the matrix and threads, if any,
- correct the edges, give the desired shape to the tooth,
- grinding and polishing,
- finishing reflections.
Black Fifth Grade
In this case, the relationship between the gums and the carious cavity is of primary importance. With a deep lesion with the closure of the lower edge of the gum, its bleeding, a good dentist will immediately determine that a correction of the gingival margin is necessary. After carrying out the appropriate manipulations with the gums, a temporary filling is applied for several days to eliminate further difficulties when installing a permanent one. The fifth class involves the use of composite materials and compomers (composite-ionomer compositions). The latter are used for superficial lesions with a significant area of localization. In cases where the aesthetic appearance is important (or the lesion affects only the enamel), light-curing composites of a specially selected shade are used.
Stages of filling fifth grade cavities
Necessary actions in the treatment of caries of the fifth grade:
- clean the surface of the tooth from plaque,
- define shade,
- administer anesthesia,
- perform preparation, removal of softened tissue,
- adjust gingival margin if necessary,
- insert retraction thread,
- apply insulation pad if necessary,
- wash off acids, dry,
- isolate from saliva,
- apply primer and adhesive,
- material laying, reflection,
- grinding and polishing,
- finishing reflections.
Sixth grade
The well-known American dentist, after whom this classification is named, identified five classes of carious cavities. For a long time, his system was used in its original form. But later, at the initiative of the World He alth Organization, the Black classes underwent minor changes - a sixth was added to them. He describes the localization of caries on the sharp edge of the incisors and on the mounds of chewing teeth.
