A preliminary study of mandibular shape.

There is a growing realization that traditional osteometric data are of uncertain scientific validity, primarily due to the lack of dissociation between size and shape parameters. This study was specifically based on the metrical definition of mandibular morphologic shape, using a technique termed medial axis transformation. It was based on the digitized mandibular outlines of three age-sexed samples of microcephalics, macrocephalics, and normocephalics. Evaluation of the derived medial axis lengths and branch point distances indicated complex patterns of mandibular shape contrasts between microcephalics and macrocephalics on the one hand and normocephalics on the other. Although larger more homogeneous samples are required to evaluate the specific factors influencing mandibular shape, the present data suggest an association between mandibular shape and cranial form.