1. Class V. cavity preparation and restoration
ONLAY

2. Class V.
Cervical caries usually develops because the affected tooth surface is unclean
Location: mainly vestibular, sometimes lingual surfaces
Between the marginal gingiva and the largest convexity of the enamel

3. Poor oral hygene
Poor brushing, wrong brushing technique
cervicalPlaque accumulation

4. class V. cavity preparation
The outline for the class V cavity preparation is primarily determined by the location and size of the carious area
Round or tapered fissure bur of suitable size enter the carious lesion
Mainly bean or kidney shape
bur’s depth can be related to the original tooth contour
Extend the preparation incisally, gingivally, mesially, and distally untill all external walls are positioned in sound tooth structure at pulpal depths ranging from 0,75 mm at the gingival wall to 1.25 mm at the incisal wall
The axial wall follows mesiodistally the contour of the facial surface of the tooth

5. Class V. cavity preparation
The axial wall will be convex mesiodistally
The axial wall will be slightly shallower pulpally at the gingival wall with little or no enamel (approximately 0.75 to 1mm in depth) than at the occlusal wall with more enamel (1 to 1.25mm in depth)

6. Removal of any remaining dentin
Round stainless steel bur
Low speed

7. Pulp protection
Apply appropriate base: axiopulpal wall should be covered
Polycarboxilate cement
Glass ionomer cement

8. Retention form
The mesial,distal, gingival, and occlusal walls of the cavity preparation being perpendicular to external tooth surface, diverge outward, thus retention form must be provided
Two retention grooves :mostly occlusally, and gingivally along the occlusoaxial, and gingivoaxial line
Depth of the grooves should approximate 0.25mm
Alternatively four retention coves may be prepared, one each in the four axialpoint angles of the preparation

9. Final procedures of cavity preparation
Cleaning the cavity
Inspecting
Finishing external walls (suitable hand instruments: chisels or margin trimmers)
Not to leave unsupported enamel

10. Insertion of amalgam
Class V amalgam restorations are placed without the use af any type of matrix
Using the amalgam carrier, insert the mixed amalgam into the preparation in small increments
Condense first into the retention areas with an appropriately sized condenser
Next condense against the mesial and distal walls of preparation
Finally build the central portion to sufficient bulk to allow for carving

11. Carving and contouring restoration
Removing excess immediately
Carving should be done paralell to the margins, using the side of the explorer tine or the Hollenback carver
Locate occlusal, mesial, distal finally the gingival margins and carve away the excess
Facial contours may be increased only enough to prevent food impaction into gingival sulcus

12. Finishing and polishing the surface of the restoration
Necessary to correct a mrginal discrepancy, or correct the contour
Polishing of high copper amalgam s is unnecessary
Not attempted within a 24 –hour period following insertion
Should be perfect continuity of surface contour

13. Class VI. Class VI. cavity preparation is used to restorate:
Incisal edge of anterior teeth
Cusp tip regions of the posterior teeth
Attritional wear has removed the enamel, and expose the underlaying dentin
Hypoplastic cusp pit

14. Class VI. cavity preparation
Enter the area with a small fissure bur
Depth of 1.5mm is sufficient to provide bulk of material for srength
Retention of restoration is ensured by the creation of small undercuts along the internal line angles
Not to remove dentin supporting the enamel