Paramolar Structures of the Upper Dentition

¹ Walter G. Zoller Memorial Dental Clinic, University of Chicago

A study of the upper paramolar cusp formation in the collection of the Chicago Natural History Museum was described.

The upper paramolar cusp formation varied in its size and pattern—from a furrow or groove delineation to various stages of cusp formation. Therefore, it was decided [see table in the PDF file] that it would be more appropriate to refer to it as "upper paramolar structures," for a particular type is only one of a group of related phenomena. These structures in human dentition probably represent the remnants of the cingulum of mammals and the lower primates.

The occurrence of this structure was very low in upper first molars compared with upper second molars or upper third molars in all the given populations. Southwestern Indians showed a higher occurrence in both deciduous and permanent molars compared with other populations. The occurrence of the paramolar structures prevailed unilaterally for the permanent molars.