M.A. Theses: Stephen Collier, 1983

Australian Aboriginal Immature Dentition

This is a study of the dentition of precontact Australian aborigines from three geographical areas - Swanport, the Murray Basin, and Broadbeach. The individuals sampled from these areas include adults and juveniles.

The major questions examined are the relationships between environment, diet, tooth size, sex, age and possible industrial use of teeth, and the rate and degree of dental attrition. The methods used in the investigation of these questions were: 1. To use dental formation stages revealed by radiography to determine age at death of the juveniles; 2. To measure all teeth to calculate mean tooth sizes for each site; 3. To assess degree of dental attrition by the application of a 14 point ordinal scale of tooth wear stages.

Rates of tooth wear were determined by calculation of the gradient of wear of the deciduous and permanent molars (wear of first molar minus wear of second molar), and by regression analysis of wear against functional age of second deciduous molars, and permanent molars and incisors. Pattern of wear was determined by comparing anterior wear (first incisor) with posterior wear (first molar).

Deciduous teeth displayed the same rates of wear for all three sites when analysed by molar wear gradient, but regressive analysis showed Swanport to have the most rapid wear. In the permanent dentition the Broadbeach juveniles exceeded the Swanport juveniles in rate of molar wear, though Broadbeach teeth exceeded those of the other sites in length but not in width. There were no significant differences in the molar wear gradients for adults between the sites.

Anterior teeth were worn relative to posterior teeth very much more in Swanport males and adolescents and Murray Basin males and females than in Broadbeach males and females and Swanport females. Environment and diet were examined and did not reveal a likely cause for this difference in attrition pattern.

Ethnographically observed industrial use of teeth, specifically in the preparation of fibre cord and manufacture of fishing nets, is proposed as the cause of this differential tooth wear between the Murray River sites and the Queensland coastal site of Broadbeach.