FLUORIDE PROFILES IN DIFFERENT SURFACES OF HUMAN PERMANENT MOLAR ENAMELS FROM A NATURALLY FLUORIDATED AND A NONFLUORIDATED AREA

The surfaces, sites and depths of fluoride profiles of enamel from a n aturally fluoridated area (West Hartlepool, WHP, 1.9 parts/10(6) F in drinking water) and a non-fluoridated area (Leeds, LDS, <0.1 parts/10( 6) F in drinking water) were examined in detail. Using a regression cu rve, y = ax(-b) comparisons of fluoride concentrations were made at de pths of 1, 3, 5, 10, 20 and 30 mu m at occlusal, middle and cervical s ites of buccal, lingual, mesial and distal molar enamel surfaces. In t he outermost enamels (<10 mu in depth), fluoride concentrations tended to be lower in the occlusal sites than in the cervical sites. In inte rior enamels (> 20 mu m in depth), the fluoride concentrations of mola rs from WHP were statistically higher than those from LDS, while few s ignificant differences were found in the outermost layers. In the mesi o- and disto-occlusal sites of approximal surfaces, there were some si gnificant differences in the exponential regression coefficients of fl uoride profiles between the two groups of molars.