Sex Differences in Intraindividual Tooth-Size Communalities

¹ Department of Growth and Genetics, Fels Research Institute, Yellow Springs, Ohio

Intraindividual tooth-size correlations were calculated for mesiodistal crown measurements of the maxillary and mandibular teeth of 137 Ohio white girls and 106 boys from the same population sample.

For each tooth involved, intraindividual tooth-size correlations were consistently higher for girls than for boys by an average of 0.10—a trend further demonstrated in 141 out of 182 individual correlations involving the upper and lower jaws.

This tendency for higher intragirl than for intraboy tooth-size correlations (like the similar sex difference in timing of tooth development and ossification timing) may be attributed to the reduplication of X-chromosomal material in the female.