The Association Between the Number of Natural Remaining Teeth and Appendicular Skeletal Muscle Mass in Korean Older Adults

Background: The aim of this study was to examine the correlation between the number of remaining natural teeth (NRT) and the appendicular skeletal muscle mass index (SMI) in older adults. Methods: This study was based on data from the 2008-2010 Korea National Health and Nutritional Examination Surveys. The participants were 2,378 older participants (984 men and 1,394 women) aged over 65 years. Survey dentists conducted oral health examinations, and ASM was measured using dual-energy X-ray absorptiometry. Results: The participants with NRT >= 20 had more ASM and SMI than those with NRT<20 in both sexes. SMI was correlated with NRT in men (r=0.018, p<0.001) and in women (r=0.007, p<0.001). The positive correlation between the NRT and SMI remained significant in men even after adjusting for age, marital status, income, smoking, drinking, physical activity, protein intake, energy intake, calcium intake, body mass index, fasting blood glucose level, medications, and prostheses (beta=0.011, p=0.001). In women, the correlation disappeared after adjustment for smoking, alcohol, physical activity, protein intake, energy intake, calcium intake, marital status, income, fasting basal glucose, medication administration, and prostheses. Conclusion: This study showed a correlation between NRT and SMI in those >= 65 years of age in Korea. The relationship persisted in men, but not in women, even after adjusting for confounders.