Oral Status of Chimpanzees in Primate Research Institute Kyoto University

Objectives: Chimpanzees are our closest animal relative and so close that their 98 % DNA is identical to us. The highly intelligent primates, chimpanzees, share many of human's physical and behavioral characteristics those actually make them attractive for us to conduct the oral health research. Data on oral status of chimpanzees are scarce. This is the first report of dental caries and periodontal diseases prevalence in unstudied chimpanzees in the Primate Research Institute Kyoto University. Methods: During a routine medical check-up under a general anesthesia the dental examinations were conducted by two calibrated examiners for 9 chimpanzees, 9Y(years old)/F(female), 9Y/F, 10Y/M(male), 25Y/F, 28Y/F, 32Y/F, 33Y/F, 42Y/F and 43Y/M. Results: Total number of teeth were 279, of which 2 were missing, 8 were decayed and none was filled. Consequently DMF Teeth were 10 and DMF Index was 1.11. Periodontal pocket depth of 5 mm was found in 8 teeth, 6 mm in 2 teeth, 7 mm in 1 tooth, 8 mm in 1 tooth and 10 mm in 1 tooth those were out of 277 teeth. Pocket depth was less than 4 mm in all other teeth. No bleeding on probing was found for 6 subjects and a mobility of teeth was none for 7 subjects. An accumulation of dental plaque and a deposition of calculus were extensive for 7 subjects. Conclusions: If these pilot samples were representative of chimpanzees target population (14 subjects) in the institute, it can be concluded that their oral health regarding caries and periodontal diseases is extremely good under the situation that no oral hygiene has ever been conducted. This indicates the key importance of their dietary conditions where more than 100 well-balanced food items were properly provided.