Social class and dental health: Pathways to tooth loss in black and white adults

Purpose To identify pathways by which social class affects tooth loss in Americans age 18–64 and to determine if paths vary by race. Methods Data used were extracted from NHANES III, and included 6,814 black and white dentate Americans age 18–64 who had had a dental exam, and had complete data on education, income and occupation. Path analysis, using an a priori model (based on Adler, 1993), explored relationships among variables that proposed to explain the relationship between social class and tooth loss. Path coefficients were created via robust regression algorithms that down-weighted outliers and managed heteroskedasticity. Explanatory variables for tooth loss included (1) social class (income, education, occupation), (2) dental care (access, frequency), (3) psychosocial factors (food insufficiency, social support, marital status), and 4) dental health damaging behaviors (smoking and diet). Models were controlled for demographic and medical factors that potentially confound the relationship between social class and tooth loss, including sex, age and diabetes. A path model for each race was created, and the models compared. Results Bivariate analyses demonstrated whites were missing fewer teeth than blacks (1 vs. 3, Mann Whitney Test, p < 0.001). Path analysis revealed that social class was directly related to tooth loss for both races; this relationship was more than twice as strong for whites than for blacks (beta = 0.24 vs. 0.10). Indirect effects of social class on tooth loss were evident through dental care and smoking for whites but not for blacks. Conclusion These results demonstrate that mechanisms by which social class affects tooth loss are likely to vary by race, and that the pathways by which social class affect dental health require more investigation, especially among blacks. Racial and social class differences in dental health are profound and require attention, and efforts towards elucidation of mechanisms by which race and social class affect dental disease are crucial towards reduction of disparities in dental health.