Number of teeth is associated with hip fracture and femoral neck bone mineral density in the NHANES

Purpose/Introduction Tooth loss has been found to be associated with fractures and osteoporosis. However, the associations between number of teeth with bone mineral density as well as with hip fractures have not been explored in the same study setting. Methods Data from the cross-sectional National Health and Nutrition Examination Survey (2005-2010, 2013-2014, and 2017-2018) with completed femoral neck bone mineral density (BMD) measurements, osteoporosis questionnaires, and dentition examinations were analyzed. A total of 15,198 participants, with a mean age of 53.9 and diverse ethnicity, males (52%), and females (48%), were analyzed. Multivariate logistic regression analyses for self-reported hip fractures, self-reported osteoporosis, and measured low femoral BMD accounting for traditional risk factors were tested for the total number of natural teeth (NoT) present, or by NoT in the anterior or posterior segments. Results Subjects with fewer natural teeth present were more likely to report a hip fracture, osteoporosis, or having lower levels of femoral neck BMD. With one additional tooth present in the mouth, there was a decreased association with self-reported hip fracture [OR(95%CI) = 0.98(0.96-0.99); P = 0.005] or with less likelihood of having low femoral neck BMD [OR(95%CI) = 0.99(0.97-1.00); P = 0.007]. Conclusions With the limitation of the cross-sectional study design, results should be interpreted cautiously, yet our analyses point to an association between a decreased number of natural teeth present and self-reported hip fractures or low femoral neck BMD. The number of teeth present could be potentially utilized for assessing risks of hip fracture and osteoporosis. Future research is needed to validate our findings.