Enamel hypoplasia in a Canadian historic sample.

Analyses of historical skeletal samples provide useful comparisons of the prevalence of skeletal indicators of stress to documentary information on health, diet, and socioeconomic status. A sample of the permanent dentitions of 253 adults from the St. Thomas' Anglican Church 19th-century skeletal sample in Belleville, Ontario, was examined macroscopically for the prevalence of enamel defects on the six anterior maxillary and mandibular teeth. The maximum frequency of hypoplasias on the left mandibular canine is 36.1%. The prevalence of enamel defects is low to moderate compared to almost all other reported frequencies in historical samples, which is consistent with historical descriptions of this developing community of middle to high socioeconomic status Canadians. Hypoplasias are significantly more frequent in males but there are no significant differences in the mean age at death between individuals with hypoplasia and those without. Calculations of the peak ages of occurrence of hypoplasias fall within the commonly observed 2-4-year range. This is not consistent with separate studies, demographic, isotopic and historical, of the introduction of complementary foods to 19th-century Belleville infants and of the weaning process. These results do not support the view that peak ages of occurrence of hypoplastic defects are associated with the cessation of breast-feeding or the weaning process in general. Am. J. Hum. Biol. 11:513-524, 1999. Copyright 1999 Wiley-Liss, Inc.