Principles of cavity prep

Question 1

define Cavity Margins

Answer 1

the junction between the walls of the cavity preparation and the external surface of the tooth

Question 2

define Cavo-Surface Margin Angle

Answer 2

the angle formed at any point, on the junction of a preparation with the unprepared surface of the tooth. Should be approximately 90° in amalgam (60°-120° clinically acceptable)

Question 3

define Line Angles

Answer 3

the line formed by the junction of two surfaces of a prepared or an prepared surface

Question 4

define Point Angles

Answer 4

the angle formed by the junction of three surfaces.

Question 5

define Occlusal/Pulpal floor

Answer 5

the occlusal floor of the cavity is the surface which is parallel to
the occlusal plane and overlies the pulp.

Question 6

define Gingival floor

Answer 6

A cavity surface in an approximal cavity which is approximately parallel to the occlusal plane and is bounded externally by the gingival margin.

Question 7

define Pulpal Axial wall

Answer 7

The axial wall is the cavity surface that is parallel to the long axis of the tooth

Question 8

define buccal/lingual axial wall

Answer 8

cavity wall is the cavity surface which is bounded by the cavosurface angle and the cavity floor

Question 9

define Isthmus

Answer 9

least wide part of the occlusal key cut in a proximo-occlusal preparation as a retentive form.