Presentation on theme: "Topic. Classification of cavities by Black. Basic principles of cavities preparation. Stages and features of the conventional preparation of carious cavities."— Presentation transcript:
Topic. Classification of cavities by Black. Basic principles of cavities preparation. Stages and features of the conventional preparation of carious cavities depending on the class. Modern methods of cavity preparation for composite materials. Alternative methods of preparation. Department of Therapeutic Dentistry Lecturer: Levkiv Mariana Ternopil State Medical University named by I. Horbachevskyy
Definition DENTAL CARIES is an irreversible microbial disease of the calcified tissues of the teeth that occurs after theirs eruption; is characterized by demineralization of the inorganic portion and destruction of the organic substance of the tooth, which often leads to cavitation.
Schematic diagram to demonstrate the requirement for diet, bacteria and dentition to interact together over time to initiate caries.
2. The anatomical: -caries of enamel -caries of dentine -caries of cement
3. Based on localization: -fissures and pits -proximal -in the cervical part (circulating)
4. Based on a severity of disease: -acute -chronic -plural (rampant) -secondary -arrested (stopped) Chronic course of superficial caries
5. Based on an intensity of lesion: -a compensated -a sub-compensated -a decompensated
6. Based on the presence of complications: -simple -complicated 7. Black’s classification
Cavity Simple cavity Compound cavity Complex cavity Feature A cavity involving only one tooth surface A cavity involving two surfaces of tooth A cavity that involves more than two surfaces of a tooth
It was based on the knowledge and evidence available at the time of Black, early 20-th of 20 century and is still used by some people today despite its limitations: it only refers to carious lesions and does not include root or secondary caries.
Class I (Simple) ◦ Developmental cavities in pit and fissures of teeth located in: Occlusal surfaces of posterior teeth Buccal or lingual pits on the molars Lingual pit near the cingulum of the maxillary incisors 15
16 Cavity (Caries) Classifications Class II (Compound, Complex) Proximal surfaces on the posterior teeth MO restorationMOD restoration
17 Class III (Simple) Interproximal surface of anterior teeth
18 Cavity (Caries) Classifications Class IV (Compound) Interproximal surface of anterior teeth and include the incisal edge
19 Cavity (Caries) Classifications Class V (Simple) Cervical third of the facial or lingual surface of the tooth Occurs because patient often sucks on sweets
20 Cavity (Caries) Classifications Class VI ( Simon’s modification) (Simple) Not part of original standard classification Later identified in order to more clearly label cavities that involve the incisal or occlusal surface worn away from abrasion
Black suggested that it was necessary to: ■ remove additional tooth structure to gain access and visibility; ■ remove all trace of demineralised enamel and dentine from the floor, walls and margins of the cavity; ■ make room for the insertion of the restorative material in sufficient bulk to provide strength; ■ provide mechanical interlocking retentive designs; ■ extend the cavity to self-cleansing areas to avoid recurrent caries.
Preparation is aimed at dissection of decayed dental hard tissues in order to stop further progression of the caries process and the creation of necessary conditions for reliable fixing of filling material, restore anatomical shape and function of the tooth. Principles of cavities preparation : The principle of "extension for prevention" (Black) The principle of "biological suitability" (Lukomskyj).
- transition of the carious cavity bottom (the surface which is turned to a pulp) to the wall should be at right angle - transition of one wall to another should be at a right angle –the shape of the cavity- is box- shaped form (except the V class) - enamel edges should be straight and smooth - bottom of the cavity should be flat or somewhat remind the form of the occlusal surface of the tooth