Variation of Dental Calculus in Captive Macaques

Dental calculus in nonhuman primates varies with diet, ecology, and immune health. As in humans, monkeys with excessive dietary carbohydrates can accumulate calculus buildup over time, although there is little information on variation of this dental pathology within nonhuman primates. Focusing on the variance between sexes and species, we scored the presence and severity of dental calculus in 91 skeletal specimens of captive adult Macaca mulatta (N=33) and Macaca fascicularis (N=58). An adult only sample was established to partially control for variance in calculus due to age, adult defined as erupted M3. Calculus was scored on each tooth from 0 to 3, with 0 as “none present” and 3 indicating “over 50% of surface affected”. Each side was scored independently. Missing teeth were evaluated for apparent causation of tooth loss. Most teeth exhibited some degree of dental calculus, but all four incisors were the most heavily calcified in both species. The anterior labial surfaces were the most impacted. The frequency of premortem canine removal in our sample prevented us from examining this trait in neighboring dentition. The least calcified were the M3s, probably due to the difference in eruption time between the incisors and the molars. We performed a one-way ANOVA on the total sample, and found no significant difference in calculus buildup between females and males for either species. We did find differences between the two species (F = 27.63, p<0.0001) with M. fascicularis exhibiting significantly more calculus.