322 Dentine Fluoride as a Biomarker of Fluoride Intake and Fluorosis

Thursday, March 22, 2012: 2 p.m. - 3:15 p.m.
Presentation Type: Poster Session
J. WEFEL1, S.M. LEVY2, B. BROFFITT2, D.V. DAWSON1, and J. HEILMAN3, 1Dows Institute, University of Iowa, Iowa City, IA, 2Prev. & Comm. Dentistry, University of Iowa, Iowa City, IA, 3College of Dentistry, University of Iowa, Iowa City, IA
The main hypothesis of this study is that the dentine fluoride of exfoliated primary second molars is a good indicator of the cumulative intake of fluoride and may be related to future permanent tooth fluorosis.

Objective:    To correlate dentine fluoride levels obtained from exfoliated teeth with cumulative fluoride intake data and age-related fluorosis data obtained from the Iowa Fluoride Study (IFS).

 Methods:    Exfoliated primary second molars collected from IFS subjects were used to determine dentine fluoride values in 90 samples via micro-diffusion and ion-specific electrode techniques.  Spearman rank correlations were used to evaluate the relationships between dentine F and fluoride intake measures reported for specified ages and age intervals.  Other analyses investigated the relationship of dentine fluoride to fluorosis.   

Results:    The 90 subjects were 55.6% female, and predominantly White (95.6%).  Dentine F determinations, measured in micrograms F/g, ranged from 0.85 to 701.75 micrograms F/g (mean  193.50 micrograms F/g, sd 149.64 micrograms F/g).   Significant (p < 0.05) positive correlations  were identified between dentine F measurements and the longitudinally-based AUC (Area Under the Curve) measures of reported F intake in mg, whether or not adjustment was made for body weight, although the rank correlations were modest ( 0.26 - 0.39).  In contrast, results assessing potential relationships between dentine F and reported fluoride intake at specific ages tended to be weaker, except for age 5 results which were similar in magnitude to AUC results.   A modest correlation (r=0.33, p=0.0041) was found between dentine F levels and a quantitative measure of fluorosis measures based upon the number of affected zones (FRI score of 2 or 3) in the permanent incisors/first molars. 

 Conclusion:   Dentine F levels are modestly associated with F intake and with permanent incisor and 1st molar fluorosis scoring.  

This abstract is based on research that was funded entirely or partially by an outside source: Supported by NIDCR RO1 DE09551, ARRA funding RO1 DE018513, GCRCP (MO1-RR00059), and NCRR (UL1RR024979)

Keywords: Dentine Fluoride and Fluorosis