This presentation serves as a guide to prepare cavity. it also comprises some materials necessary to efficiently do the procedure.

1. Equipment and materials used in
class 3 cavity preparation

2. 1. Equipment
 Explorer: used to detect or explore the
cavity
 Radiographic machine (x-ray): too used to
examine the decayed portion of tooth
 Dental light: for examination

3. cont’
 Round tungsten carbide bur or diamond :used
with high speed handpiece
 Gingival margin trimmer : used for smoothing
the prepared cavity and too for trimming the
composite after filling
 Finishing bur

4. 2. Materials
 Resin composite: is used to improve the esthetic
in anterior teeth
 Resin modified glass ionomer materials – used
for filling dental caries with margins extending
onto the root surface

5. Steps for cavity preparation
 Establish outline form – based on the location and extent of the carious
lesion
 Obtain resistance form – so that the restoration is resistant to
displacement.
 Obtain retention form - obtained by shaping the preparation or via bonding
procedures that attach the restorative materials to the tooth structure.
 Obtain convenience form- allows adequate observation, accessibility and
ease of operation during preparation and restoration of the tooth.
 Remove remaining carious dentin
 Finish enamel walls and cavo-surface margins- it involves making the walls
relatively smooth
 Clean the preparation- it includes washing and scrubbing away any debris
in the preparation and drying the preparation.

6. Principles for class 3 Cavity prep.
Shaft of bur should not
be parallel to proximal
plane
Access through labial
embrasure

7. Principles for class 3 prep cont’
Center on gingival of contact
area
 Extend lingually until contact is broken.

8. WE THANK YOU ALL TO LISTEN !!

9. Reference
 Operative dentistry
 http://student.ahc.umn.edu/dental/2012/6436/Cl3%20co
mp%20prep.09.pdf
 http://collections.nlm.nih.gov/ext/dw/51030490R/PDF/51
030490R.pdf