Impact of socio-economic factors on residuals of tooth loss independent of dental disease

Objectives: To identify associations between socio-economic indicators and tooth loss conditional on caries and periodontal disease. Methods: Analyses were conducted on 14,871 dentate adults, using National Health and Nutrition Examination Survey-III data. Multivariate linear regression was used to explore the relationship between tooth loss and socio-economic factors, using residuals of number of missing teeth conditional on age, decay filled surfaces, and severe periodontal disease. Results: Using a residually adjusted outcome allowed for direct interpretation of the amount of variation in number of missing teeth explained by the socio-economic variables conditional on age, decay and severe periodontal disease. In multivariate models Mexican American ethnicity was associated with significantly fewer missing teeth compared to Whites (Β=-1.43, 95%CI:-1.78,-1.07). At least 8 years of education was associated with increased number of missing teeth compared to >12 years (Β=0.54, 95%CI: 0.04,1.05). Dental care utilization was strongly associated with number of missing teeth, adjusting for age and dental disease only. In multivariate analyses, only visiting a dentist “whenever needed” was significantly associated with greater number of missing teeth compared to visiting “once a year” (Β=0.35, 95%CI: 0.13,0.57). Conclusions: Socio-economic factors are associated with tooth loss conditional dental disease. Social factors irrespective of disease severity play an important role in the decision to extract. Traditional socio-economic indicators may not be as strong of predictors of tooth loss in racial/ethnic sub-populations as for Whites. Possibly cultural differences in extraction, utilization of dental services, or differential care may be more important predictors of tooth loss for Blacks and Mexican-Americans.