Eruption sequence similarities in the maxilla and mandible.

Maxillary and mandibular dentitions exhibit correspondences to a truly remarkable degree. Correlations of upper and lower opponents (isomeres) in both the deciduous and permanent dentitions are exceeded only slightly by right-left (antimere) correspondences, both in crown size (Garn and Burdi, J Dent Res 50:1407, 1971) and in tooth emergence timing (Garn and Smith, J Dent Res, in press, 1980). Under these circumstances one might also expect inter-jaw correspondences in the order of tooth emergence, such that an M2P2 or P2M2 emergence order in one jaw would be associated with the same sequence in the opposing dentition. To explore this possibility we have made use of two data sources, restricting data analysis to those boys and girls for whom sequences were completely clear for both upper and lower dentitions. The first data base, which we have extensively explored, is that of the Ten-State Nutritional Survey of 1968-1970 (Garn et al., J Dent Res 51:1506, 1972). The second data base includes the participants of the University of Michigan Longitudinal Study (Moyers et al., Standards ofHuman Occlusal Development, Ann Arbor, Center for Human Growth and Development, 1976). The first data base provides 220 black individuals and 284 white individuals, analyzed separately because of population differences in emergence sequence and timing. The second data base yields a total of 60 boys and