Periodontal disease susceptible matrilines in the Cayo Santiago Macaca mulatta macaques.

OBJECTIVE AND BACKGROUND: The expression of periodontitis, including age of onset, extent, and severity is considered to represent an interaction of the individual's oral microbiome and host response to the microbial challenge that is modified by both genetics and environmental factors. The aim of this study was to determine the distribution of periodontitis in a population of nonhuman primates, to document features of familial distribution that could reflect heritability and transmission of microbes with enhanced virulence. MATERIAL AND METHODS: This report presents our findings from evaluation of periodontal disease bone defects in skulls from 569 animals (5-31 years of age) derived from the skeletons of the rhesus monkeys (Macaca mulatta) of Cayo Santiago derived from eight matrilines over 6-9 generations. The distance from the base of alveolar bone to the cemento-enamel junction on 1st /2nd premolars and 1st /2nd molars from all four quadrants was evaluated as a measure of periodontal disease. Additionally, we documented the presence of periodontitis in 79 living descendants within these matrilines. RESULTS: The results demonstrated an increased extent and severity of periodontitis with aging across all matrilines. Extensive heterogeneity in disease expression was observed among the animals and this was linked to specific periodontitis susceptible matrilines. Moreover, we identified some matrilines in which the members appeared to show some resistance to more severe disease, even with aging. CONCLUSION: Linking these disease variations to multigenerational matriarchal family units supported familial susceptibility of periodontitis. This familial disease relationship was reinforced by the distribution of naturally-occurring periodontitis in the living descendants.

Odontogenic abscesses in rhesus macaques (Macaca mulatta) of Cayo Santiago.

OBJECTIVES: Odontogenic abscesses are one of the most common dental diseases causing maxillofacial skeletal lesions. They affect the individual's ability to maintain the dental structures necessary to obtain adequate nutrition for survival and reproduction. In this study, the prevalence and pattern of odontogenic abscesses in relation to age, sex, matriline, and living periods were investigated in adult rhesus macaque skeletons of the free-ranging colony on Cayo Santiago, Puerto Rico. MATERIALS AND METHODS: The skulls used for this study were from the skeletons of 752 adult rhesus macaques, aged 8-31 years, and born between 1951 and 2000. They came from 66 matrilines ranging from 1 to 88 individuals. Fistulae or skeletal lesions caused by odontogenic abscesses drainage, carious lesions, tooth fractures, tooth loss, and alveolar resorption were evaluated visually. RESULTS: Seventy-two specimens (9.57%) had odontogenic abscesses of varying severity. Males had a significantly higher prevalence than females. The prevalence of odontogenic abscesses in several matrilines was significantly higher than in the population as a whole. Animals born between 1950 and 1965 tended to have a higher prevalence of odontogenic abscesses than those born in later periods. DISCUSSION: These results suggest that oral pathologies, such as dental and periodontal abscesses in rhesus macaques are fairly common, which may indicate familial effects interwoven with ecological and social factors. The closeness of the rhesus and human genomes allows insights to understand of the epidemiology of these diseases in the human population. Further assessment of the role played by environmental and familial factors on rhesus oral health and disease are warranted.

Familial periodontal disease in the Cayo Santiago rhesus macaques.

Substantial ongoing research continues to explore the contribution of genetics and environment to the onset, extent and severity of periodontal disease(s). Existing evidence supports that periodontal disease appears to have an increased prevalence in family units with a member having aggressive periodontitis. We have been using the nonhuman primate as a model of periodontal disease for over 25 years with these species demonstrating naturally occurring periodontal disease that increases with age. This report details our findings from evaluation of periodontal disease in skulls from 97 animals (5-31 years of age) derived from the skeletons of the rhesus monkeys (Macaca mulatta) on Cayo Santiago. Periodontal disease was evaluated by determining the distance from the base of the alveolar bone defect to the cemento-enamel junction on 1st/2nd premolars and 1st/2nd molars from all four quadrants. The results demonstrated an increasing extent and severity of periodontitis with aging across the population of animals beyond only compensatory eruption. Importantly, irrespective of age, extensive heterogeneity in disease expression was observed among the animals. Linking these variations to multi-generational matriarchal family units supported familial susceptibility of periodontitis. As the current generations of animals that are descendants from these matrilines are alive, studies can be conducted to explore an array of underlying factors that could account for susceptibility or resistance to periodontal disease.