Scanning electron microscopy of cusp-tip pits in developing and mature human dentitions.

A variety of cusp-tip pits were observed with the scanning electron microscope (SEM) on canines and molars of both deciduous and permanent dentitions. Larger pits or craters usually were single and funnel-shaped with a narrow 100 micron base widening to 300-400 micron peripheral opening; smaller pits were in groups. As defects occur precisely in the tips of cusps, developing cusps fetal dentitions were examined for a consistent structural pattern which could explain cusp-tip pit development.