Occlusal Aspect
From the occlusal aspect, some differences are to be noted between the two premolars. On the second premolar, the outline of the crown is more rounded or oval, rather than angular (see Figures 9-21 and 9-24). There are, of course, exceptions. The central developmental groove is shorter and more irregular, and there is a tendency toward multiple supplementary grooves radiating from the central groove. These supplementary grooves terminate in shallow depressions in the enamel that may extend out to the cusp ridges.
This arrangement makes for an irregular occlusal surface and gives the surface a very wrinkled appearance.
Occlusal AspectFrom the occlusal aspect, some differences are to be noted between the two premolars. On the second premolar, the outline of the crown is more rounded or oval, rather than angular (see Figures 9-21 and 9-24). There are, of course, exceptions. The central developmental groove is shorter and more irregular, and there is a tendency toward multiple supplementary grooves radiating from the central groove. These supplementary grooves terminate in shallow depressions in the enamel that may extend out to the cusp ridges.This arrangement makes for an irregular occlusal surface and gives the surface a very wrinkled appearance.
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