TOILET OF THE CAVITY:
This is the act of freeing the preparation walls and margins from objects that may interfere with proper adaptability and behavior of the restorative material.
It is accomplished by
Removal of all enamel and dentin chips due to excavation and grinding with warm water.
Drying with air syringe.
Sterilization.
Englander et al have shown that silver nitrate [...]
FINISHING OF THE CAVITY WALLS:
It is the further development, when indicated, of a specific cavosurface design and degree of smoothness that produces the maximum effectiveness of the restorative material being used.
OBJECTIVES:
To create the best marginal seal possible between the restorative material and the tooth structure.
Afford a smooth marginal junction.
Provide maximum strength of both tooth and [...]
PULP PROTECTION:
Though not taken in principles of cavity preparation it is one of the important steps before final restoration.
Pulpal injury can result due to:
Heat generated by injudicious cutting.
Restorative material with good thermal conductivity.
Chemical from the restorative materials.
Galvanic currents
Microleakage.
Liners and bases are used fro pulp protection. Liners are volatile or aqueous suspensions or dispersion of zinc [...]
REMOVAL OF REMAINING CARIOUS DENTIN OR OLD RESTORATIONS:
It is the elimination of any infected carious tooth structure or faulty restorations left in the tooth after initial cavity preparation.
Caries left in the pulpal/ axial floor is excavated thoroughly making the cavity deeper. 0.75- 1 mm of dentin should cover the pulp. All the infected/ soft dentin [...]
CONVENIENCE FORM
Definition: Convenience form is defined as that form of cavity preparation that allows adequate observation, accessibility and case of operation in preparing and restoring the cavity.
Modification in tooth preparation for convenience form:
Occlusal step in classII.
Labial/lingual access for classIII/classIV.
Occlusal divergence of cavity walls in cast restorations.
INSTRUMENT MODIFICATION:
Contra angling
Bayoneting
Addition of angles to the shank of the [...]