Distance gradient in prenatal dental development.

In postnatal dental development, and in crown size itself, there is a demonstrable "distance gradient" so that teeth closer together within a jaw quadrant show higher correlations. Thus, adjacent teeth exhibit systematically higher commonality in both tooth formation and crown size than more remote teeth in the same quadrant, despite absolute differences in formation (calcification, root elongation, and movement) and in crown size (specifically the mesiodistal crown diameter) (S. M. GARN, A. B. LEWIS, and R. S. KEREWSKY, J Dent Res 44: 350-354, 1965 and 46:1481, 1967; S. M. GARN, C. G. ROHMANN, T. BLUMENTHAL, and F. N. SILVERMAN, Amer J Phys Anthrop 27:75-82, 1967). We applied this analytic model to intraindividual correlations of tooth stage in the 20 deciduous teeth of 52 male and female embryos in the 14 to 58 mm size range; all embryos