Changes in Dental Arch Dimensions Expressed on the Basis of Tooth Eruption as a Measure of Biologic Age

¹ Forsyth Dental Center, Harvard School of Dental Medicine, Harvard School of Public Health

Arch dimensions were studied from serial dental casts of 184 individuals observed between three to five and sixteen to eighteen years, together with additional data of 48 individuals which included only the incisor transition.

The findings serve principally to illustrate differences in mean patterns for the intercanine distance and arch length on a biologic age scale, as opposed to the use of chronologic age.

For the dentition, tooth emergence and eruption are more suitable as parameters of dental development than chronologic age in defining the changes in arch dimensions as they actually occur in the average child. Except for arch length, the variances in the absolute intercanine distance as well as in the increments of both arch dimensions were not appreciably decreased, as was expected by the more homogeneous sample composition when grouping individuals at similar stages of development.