Figure 4-22. Maxillary right cuspid.
a. Facial Surface. The facial surface is markedly convex in all directions. The
facial surface has two longitudinal (axial) grooves delineating the development lobes.
The middle lobes are developed into a prominent ridge running lengthwise from the
cusp area to the cervical third of this surface. The mesial cusp arm is shorter than the
distal cusp arm.
b. Lingual Surface. The lingual surface is scoop-like or shovel-like in
appearance and is bounded by prominent mesial and distal marginal ridges. It is
narrower than the facial surface because both proximal surfaces converge toward the
lingual. The cingulum is located in the cervical third and is slightly distal to the midline
of the crown. The incisal two-thirds is concave and the cervical one-third is convex in
outline.
c. Mesial Surface. The mesial surface is somewhat triangular in shape with the
apex of the triangle toward the incisal edge. It has a slight faciolingual convexity. The
contact area is located in the incisal third.
d. Distal Surface. The distal surface is smaller in area but similar in outline to
the mesial surface. Its contours are more convex than those of the mesial surface. The
contact is located near the junction of the middle and incisal thirds.
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