Classes for Black: the location of carious cavities, classification and treatment of caries

Why classify dental caries? This is only at first glance a simple disease known to everyone. For dentists, there is a differentiation of its various types, and each of them requires its own special approach to treatment.

Caries varies

Caries - the most common disease of the mouth, developing in different areas of the teeth, can differ and the clinical picture of the course of the process. For the convenience of treatment, the correct choice of tooth preparation and the material used for filling, caries types are usually classified. So allocate classes on Black, the depth of defeat, the degree of activity of the process of destruction, the presence of complications, the clinical nature and localization of the lesion.

Especially popular is the classification proposed in 1986 by the American dentist J. Black. Its goal was to systematize the principles of treatment for various types of carious tooth lesions.

Classes by Black

Black identified five classes of localization on the surface, that is, depending on where exactly the carious cavity is located:

1. Localization in fissures (grooves and gaps in the chewing surface enamel), pit molars and premolars (large and small molars), canines and incisors.
2. Two or more surfaces are affected - medial and distal (caries on the front teeth) or occlusal (cutting and chewing surface) of molars and premolars are captured.
3. The development of the disease on the medial and distal part of the canines and incisors.
4. The localization is the same as in the third class, plus the angle of the crown part or the cutting surface is captured.
5. The cavity occupies the cervical portion of any group of teeth.

Classes for Black systemize all possible options for the development of caries, for each of them provides for a separate treatment, a method of dissecting a diseased tooth and installing a seal.

First class in Black

The carious cavity located in this way increases the risk of breaking the edge of the filling due to high pressure on it when chewing. When preparing the tooth, measures are provided to exclude this possibility. This occurs by reducing the bevel of the enamel and applying a thicker layer of filling material. When using a composite with chemical curing, it is applied parallel to the bottom of the carious cavity, since the shrinkage will be directed towards the pulp. If a light curing material is used, it is laid with oblique layers. Shrinkage in this case will be directed to the source of polymerization. Layers should lie from the middle of the bottom to the edge of the cavity, the glare occurs through the side walls, and after - perpendicular to the masticatory surface. As a result, a tight fit of the seal in the cavity.

The stages of filling the first class cavities

Such actions should be taken by the dentist in order to cure the 1st grade in Black:

• Anesthetize (use anesthetic gel or lidocaine spray) ,
• Prepare the tooth (preparation involves drilling a carious area deep into a hard tissue),
• If necessary, apply an insulating pad (to prevent the composite from affecting the pulp and to irritate it),
• Etch and wash acid, dry the cavity,
• Isolate from saliva,
• If necessary, apply a primer (for the preparation of dentin),
• Apply an adhesive (a bonding element between the composite and the dental tissue or primer),
• Layer by layer to apply the material, to conduct its curing,
• Adjust to the desired shape, finish and polish,
• To make a glare (final curing).

Second class in Black

Having its complexities, the 2nd class in Black suggests in its treatment two main tasks - to create a strong contact between the teeth and ensure a tight fit of the composite to the edge of the main cavity. Often the sealing process can be complicated by the appearance of an overhanging edge of the filling, the absence of contact between the teeth or the material with a carious cavity. To prevent this, thin matrices are used, the tooth is displaced (to the extent possible) by means of wooden wedges. In interdental space, the matrix is inserted and fixed with a wedge, then moistened with water. Wedge swells and pushes back the tooth. This method, when sealed, avoids overhanging the edge of the filling, which in turn can cause gum disease. The tight adherence of the material to the cavity ensures the use of an adhesive, a binder, since the composite itself can be firmly bonded only to the enamel, but not to the dentin.

Stages of filling the cavities of the second class

Classes for Black in the treatment have similar points, but each of them requires special nuances of sealing. Here are the steps for the second class:

• anesthesia,
• Preparation,
• If necessary, correction of the gums,
• Installation of a matrix with the introduction of a wooden wedge or holder,
• If necessary, spreading teeth,
• The application of an insulating gasket (if necessary),
• The procedure of etching, acid washing and drying
  Cavity,
• Isolation of the tooth from saliva,
• Primer and adhesive application,
• If necessary - restoration of the enamel edge (if there is none),
• Overlay composite in layers,
• Matrix and wedge extraction,
• Interdental contact control,
• Correction, polishing,
• Finishing glare.

Third and fourth grades

Here the main role is played by the selection of the color of the filling material, because in this case caries on the front teeth is localized. In connection with the different coefficient of transparency of dentin and enamel, it is necessary to use a composite of two different colors during treatment. It is necessary for the tooth to appear uniform, and the seal does not look like a patch. To create the most natural effect, use white material shades that mimic dentin, and almost transparent - to recreate the enamel. To make the transition imperceptible, the bevel of the enamel overlaps by 2-3 mm. It is important that such a delicate work involved a good dentist who can correctly determine the transparency of the tooth. There are three of its degrees: opaque (usually yellowish hue, even the cutting edge is opaque), transparent (yellow-gray hues, cutting edge transparent), very transparent (grayish shade, transparent edge occupies a third of the tooth.

Stages of filling cavities 3 and 4 classes

To seal the third and fourth classes of cavities by Black, the dentist needs to do the following:

• Clean the surface of the plaque,
• Determine the shade of the tooth,
• Anesthetize,
• Prepare the tooth, release from the affected tissue,
• To establish retraction threads or matrices, when necessary (the gingival margin is affected),
• Apply an insulating gasket,
• If necessary, restore the contours of the teeth,
• Wash acid and dry the cavity,
• Isolate saliva,
• Apply primer (optional) and adhesive,
• Layer layers of plaiting material,
• Removal of the matrix and filaments, if any,
• Adjust the edges, give the desired shape of the tooth,
• Grinding and polishing,
• Finishing glare.

The fifth grade in Black

In this case, the main importance is the relationship between the gum and the carious cavity. With a deep lesion with the closure of the lower edge of the gum, its bleeding, a good dentist will immediately determine that correction of the gingival margin is necessary. After the appropriate manipulations with the gum for a few days, a temporary seal is applied to exclude further difficulties in setting a constant. The fifth class involves the use of composite materials and compomers (composite-ionomer compositions). The second ones are used for superficial lesions with a significant localization site. In cases where the aesthetic appearance is important (or the damage affects only the enamel), light-curing composites of a specially selected shade are used.

Stages of filling of cavities of the fifth class

The necessary action in the treatment of caries of the fifth class:

• Clean the surface of the tooth from plaque,
• Determine the shade,
• Conduct anesthesia,
• Perform preparation, removal of soft tissue,
• Correct the gingival margin, if necessary,
• Introduce a retraction thread,
• Apply a gasket for insulation if necessary,
• Wash acid, dry,
• Isolate from saliva,
• Apply primer and adhesive,
• Styling, lighting,
• Grinding and polishing,
• Finishing glare.

Sixth grade

A well-known American dentist, named after this classification, distinguished five classes of carious cavities. For a long time his system was used in its original form. But later on the initiative of the World Health Organization classes on Black have undergone minor changes - they were added to the sixth. He describes the localization of caries on the sharp edge of the incisors and on the mounds of the chewing teeth.