Cavity Classification And Nomenclature 2o6w4n

Cavity Classification and Nomenclature

What is the Cavity? Cavity is a defect in hard tooth structure. What is cavity preparation? It is surgical excision of the lesion in hard tooth structure and modification in the cavity to accept the restoration and be retentive to this restoration and resistant to 2 fracture.

.Classification of cavities 1. Anatomical classification. 2. Black's classification. 3. Numerical classification. 4. Mount‫؛‬s Site Stage classification.

Anatomical classification 1. Pit and fissure

2. Smooth surface

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Black's classification 1. Class I: Pit and fissure any where it exists 2. Class II: Proximal of posterior teeth. 3. Class III: Proximal of anterior teeth not involving incisal angle 4. Class IV: Proximal of anterior teeth involving incisal angle 5. Class V: cervical area buccal and lingual in all teeth 6. Class VI: Cusp tip and incisal edge. 5

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:Numerical classification • According to no. of surfaces involved 1. Simple … One surface Ex. Simple class I,II.III and V 2. Compound…Two surfaces Ex. Compound class I,II and III 3. Complex…More than two surfaces Ex complex class I,II ,III and IV 10

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Classification by Mount and .Hume • Site Stage classification: • (Si/Sta) • It includes 3 sites and 5 sizes.

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:The three sites of carious lesions

Site 1: Pits, fissures and enamel defects on occlusal surfaces of posterior teeth or other smooth surfaces Site 2: Proximal enamel immediately below areas in with adjacent teeth

Site 3: The cervical one third of the crown or followin gingival recession, the exposed root 13

The five sizes of carious lesions Size 0: Lesion with no surface discontinuity may not require surgical intervention. Size1:Minimal involvement of dentin just beyond treatment by remineralization alone. Size2: Moderate involvement of dentin. Following cavity preparation, remaining enamel is sound, well ed by dentin and not likely to fail under normal occlusal load. The remaining tooth structure is sufficiently strong to . 14 the restoration.

Size 3: the cavity is enlarged beyond moderate. The remaining tooth structure is weakened to the extent that cups or incisal edges are split, or are likely to fail or left exposed to occlusal or incisal load. the cavity needs to be further enlarged so that the restoration can be designed to provide and protection to the remaining tooth structure. Size4: Extensive caries with bulk loss of tooth structure has already occurred. 15

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Cavity preparation Nomenclature. Enamel wall: Portion of cavity wall in enamel. Dentin wall: Portion of cavity wall in dentin. Dentino-Enamel Junction (DEJ) Cemento - Enamel Junction (CEJ) 17

• Cavo-suface margin: • It is the external margins of the cavity • Cavo-suface angle: • It is the angle formed between the cavity wall and the external too surface (it is interior angle inside tooth structure). • Isthmus: • It is the portion of the compound and complex 18 cavities that ing the two portions.

Walls and Angles: :Blacks Rules 1. Rule I: Walls named as the corresponding tooth surface. 2. Rule II: Walls over the pulp and perpendicular to long axis called pulpal. 3. Rule III: Walls over the pulp and parallel to long axis called axial. 4. Rule IV: Line angle is meeting of 2 surfaces and named from the two walls 5. 19Rule V: Point angle is meeting of 3 surfaces and named from the three walls

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