Dental Fluorosis and Oral Health-Related Quality of Life (OHRQoL): NHANES 2003-2004

Objectives: The purpose of this study is to investigate the influence of dental fluorosis on oral health-related quality of life (OHRQoL) among adolescents and adults in the United States.
Methods: We analyzed the National Health and Nutrition Examination Survey (NHANES) 2003 – 2004 data of individuals aged 16-49 years, who completed the home interview and dental fluorosis examination (n=3,541). OHRQoL was calculated as sum of 7-items out of the 14-items NHANES Oral Health Impact Profile. OHRQoL score can range 6-28 (lower score indicates better oral health). OHRQoL was further divided into two sub-categories: psychological/social (3-items) and physical/functional disabilities (4-items). Fluorosis experience was measured by Dean’s Index. Other covariates were socio-demographic characteristics, DMFT, self-perceived mouth/teeth condition (1-item), and previous dental visit (time and reason). Bivariate and multivariable analyses were conducted with OHRQoL (overall and two sub-categories) as outcome. All analyses were weighted and adjusted for the complex design of the NHANES survey, using SAS 9.3 survey procedures.
Results: The overall distribution of dental fluorosis was: unaffected (41.9%), questionable (31.1%), very mild (20.0%), mild (5.5%) and moderate to severe (2%). Simple regression analysis, with OHRQoL as outcome and fluorosis as predictor, showed that OHRQoL was significantly decreased with higher level of fluorosis severity (β-coefficient=-0.27, p-value=0.02). Severity of fluorosis was significantly inversely associated with DMFT score (β-coefficient=-1.36, p-value <0.0001). The lower DMFT scores explain the better perception of oral health (lower OHRQoL scores) in higher fluorosis severity groups (β-coefficient=0.13, p-value <0.0001). After controlling of DMFT and covariates in a multiple regression model, fluorosis severity was no longer significantly associated with lower OHRQoL score. Anterior teeth-only analysis showed the same results.
Conclusions: The results demonstrated clearly the inverse relationship between dental caries and fluorosis. The findings also suggest that the benefit from fluorides outweighs the esthetic impact from fluorosis in the US population.