Age change of molar wear in the Japanese macaque (Macaca fuscata fuscata)

Abstract

Age change of molar wear in the Japanese macaque (Macaca fuscata fuscata) was studied. Molar wear was graded into stages and categorically scored. Sum of wear scores were tabulated for each tooth type. Then scores of all molars were summed to obtain a total wear score. Wear scores were significantly correlated with age, although a detailed assessment of the pattern of wear rate was not possible with the present categorical system. In all molars, wear in males tended to be faster than that in females. This difference was statistically significant in both maxillary and mandibular second molars. Comparison among molar positions indicated significant differences in wear rate between the first or second and the third molars. Third molars tended to wear more slowly than the mesial molars although no difference in wear scores were detected between the third and the other molars after the relative age of approximately 13 years. The results of this study could be used as a standard for assessing wear rate and pattern in molars of the captive Japanese macaque.