Bilateral Asymmetry in Tooth Cusp Occurrence in Human Monozygotic Twins, Dizygotic Twins, and Nontwins

Abstract

Bilateral asymmetry in cusp occurrence of the hypoconulid and seventh cusps on the permanent mandibular first molar and the number of cusps on the mandibular premolars was examined in specimens from monozygotic twins, dizygotic twins, and nontwins. Bilateral asymmetry was similar in frequency and displayed no sex or side differences in the three samples.