TOOTH PREPARATION TERMINOLOGY
A termed simple if only one tooth surface is involved, compound if two surfaces are involved, and complex if a
preparation involves three or more surfaces
ABBREVIATED DESCRIPTIONS OF TOOTH PREPARATIONS
Tooth preparation is abbreviated by using the first letter, capitalized, of each tooth surface involved,
O = Occlusal tooth preparation
MO = Mesial and Occlusal surfaces
MOD = Mesial, Occlusal, and Distal Surfaces
TOOTH PREPARATION WALLS
INTERNAL WALL
The prepared surfaces that does not extend to the external tooth surfaces
- Pulp and Axial
AXIAL WALL
The internal wall parallel to the long axis of the tooth
PULPAL WALL (FLOOR)
The internal wall that is perpendicular to the axis of the tooth and occlusal of the pulp.
EXTERNAL WALL
The prepared surface that extends to the external tooth surface.
A wall takes the name of the tooth surface that the wall is adjacent to
1. FLOOR (SEAT)
- The prepared wall that is reasonably horizontal and perpendicular to the occlusal forces that are
directed occlusogingivally.
- Pulpal and gingival floors.
- This preparation feature increases the resistance form of the restored tooth against post-
restorative fracture.
2. ENAMEL WALL
- Portion of a prepared external wall consisting of enamel
-
3. DENTINAL WALL
- Portion of a prepared external wall consisting of dentin, in which mechanical retention features
may be located
TOOTH PREPARATION ANGLES
The junction of two or more prepared surfaces is referred to as angle
The junction is almost always “softened” so as to present a slightly rounded configuration.
1. LINE ANGLE – the junction of two planar surfaces of different orientation along a line.
- Internal line angle is line angle whose apex points into the tooth
- External line angle is the line angle whose apex points away from the tooth
2. POINT ANGLE – the junction of three planar surfaces of different orientation
CAVOSURFACE ANGLE AND CAVOSURFACE MARGIN
The angle of tooth structure formed by the junction of a prepared wall and the external surface of the tooth.
The actual junction I referred to as cavosurface margin
Carvosurfac angle differ with the location on the tooth, the direction of the enamel rods on the prepared wall,
or the type of restorative material be used
A termed simple if only one tooth surface is involved, compound if two surfaces are involved, and complex if a
preparation involves three or more surfaces
ABBREVIATED DESCRIPTIONS OF TOOTH PREPARATIONS
Tooth preparation is abbreviated by using the first letter, capitalized, of each tooth surface involved,
O = Occlusal tooth preparation
MO = Mesial and Occlusal surfaces
MOD = Mesial, Occlusal, and Distal Surfaces
TOOTH PREPARATION WALLS
INTERNAL WALL
The prepared surfaces that does not extend to the external tooth surfaces
- Pulp and Axial
AXIAL WALL
The internal wall parallel to the long axis of the tooth
PULPAL WALL (FLOOR)
The internal wall that is perpendicular to the axis of the tooth and occlusal of the pulp.
EXTERNAL WALL
The prepared surface that extends to the external tooth surface.
A wall takes the name of the tooth surface that the wall is adjacent to
1. FLOOR (SEAT)
- The prepared wall that is reasonably horizontal and perpendicular to the occlusal forces that are
directed occlusogingivally.
- Pulpal and gingival floors.
- This preparation feature increases the resistance form of the restored tooth against post-
restorative fracture.
2. ENAMEL WALL
- Portion of a prepared external wall consisting of enamel
-
3. DENTINAL WALL
- Portion of a prepared external wall consisting of dentin, in which mechanical retention features
may be located
TOOTH PREPARATION ANGLES
The junction of two or more prepared surfaces is referred to as angle
The junction is almost always “softened” so as to present a slightly rounded configuration.
1. LINE ANGLE – the junction of two planar surfaces of different orientation along a line.
- Internal line angle is line angle whose apex points into the tooth
- External line angle is the line angle whose apex points away from the tooth
2. POINT ANGLE – the junction of three planar surfaces of different orientation
CAVOSURFACE ANGLE AND CAVOSURFACE MARGIN
The angle of tooth structure formed by the junction of a prepared wall and the external surface of the tooth.
The actual junction I referred to as cavosurface margin
Carvosurfac angle differ with the location on the tooth, the direction of the enamel rods on the prepared wall,
or the type of restorative material be used
