Cause-Specific Tooth Loss and Its Heterogeneous Association With Systemic Health

Background Epidemiological studies have frequently reported tooth loss as a homogenous exposure but ignored its diverse aetiologies. This study aimed to investigate the associations between cause-specific tooth loss and systemic health outcomes. Methods This cross-sectional study based on data from the National Health and Nutrition Examination Survey (NHANES). A main cohort from 2011 to 2018 was established to evaluate mental health and physical function, and a sub-cohort from 2011 to 2014 was designed to assess cognitive function. Tooth loss was classified using the Coronal Caries Tooth Count variables. Survey-weighted linear regression models adjusted for sociodemographic and clinical covariates were used to estimate the associations. Results Pathological tooth loss was associated with more severe depression, worse physical function, and lower verbal fluency. Non-pathological tooth loss showed no significant associations with any outcome. Associations with delayed recall and processing speed were attenuated after adjustment. Sensitivity analyses adjusting for current periodontal status and untreated caries produced essentially unchanged estimates, and a graded pattern was observed with increasing numbers of teeth lost to disease. Conclusions The systemic health consequences of tooth loss are highly heterogeneous and depend on the underlying aetiology. Pathological tooth loss is associated with poorer mental health, physical function, and verbal fluency. These findings support the integration of aetiology-based tooth loss classifications into epidemiological research.