CLASS III CAVITIES

¨When the contact is open the outline is triangular with base towards the gingival aspect of the cavity

¨Gingival cavity wall is inclined occlusally to parallel the enamel rod direction

CLASS II CAVITIES

¨Due to presence of broad contact area, the gingival floor of the proximal box should be wide

¨The box should converge occlusally with the buccal and lingual wall paralleling the external tooth surface .the walls of proximal box should meet the occlusal wall in a straight line

CLASS I CAVITIES

¨Due to narrow occlusal table isthmus should not be more than 1/3^rd the intercuspal distance in the case of small carious lesion

¨The depth should not be more

 than 0.5 mm into the dentin

MODIFICATION OF CAVITY PREPARATION IN PRIMARY TEETH

   Factors to be considered while restoring primary teeth

§The smaller tooth dimension of the deciduous dentition

§The thin enamel covering the teeth

§Broad contact area

§Proximity of the pulp chamber

§Narrow occlusal table

RECENT CONCEPT

            PRINCIPLES OF RECENT CONCEPT 

    ¨Cavity design should be dictated under the site and extent of the lesion

    ¨Should not be in expectation of extending cavity out to the “caries free” area.         

    ¨Restorative material should be one that displays some degree of biological activity

FINAL PROCEDURE

¨It include removing all chips and lose debris that have accumulated ,drying the preparation and making a final complete inspection of the preparation for any remaining infected dentin or any condition that renders the preparation unacceptable to receive the restorative material.

FINISHING EXTERNAL WALLS AND MARGINS

¨It is the further development when indicated of a specific cavosurface design and degree of smoothness  that produces maximum effectiveness of the restorative material used.