The procedure (in Class III restoration) shown is:
Larger preparations may require additional beveling of the accessible enamel walls to enhance retention by bonding these enamel margins, which are beveled with a flame-shaped or round diamond instrument.
The bevel is prepared by creating a 45-degree angle to the external surface and to a width of 0.5 to 2 mm, depending on the size of the preparation, location of the margin, and esthetic requirements of the restoration.
Smoothening of enamel margin
Beveling of the external tooth surface
Refining the proximal walls
Flaring of proximal walls