Alkali-soluble and insoluble fluoride in erupted and unerupted human enamel from a high fluoride area with a low fluorosis score.
The amounts of fluoroapatite and 'CaF2-like' fluoride (F) were determined in enamel of unerupted and erupted teeth that had been exposed in vivo to 1.8-2.6 parts/10(6) F in the drinking water and to brushing with F dentifrice at least once a day, and occasionally to a F mouth-rinse (0.022% F). Enamel was sampled by acid-etching and the F levels were measured with an adapted F ion-selective electrode. More F was built into the deeper enamel in the high-F area than in a similar low-F area. Unerupted enamel did not etch significantly (p > 0.05) deeper than erupted enamel. No significant differences (p > 0.05) were found in the F concentrations amongst the following: alkali-washed erupted, unwashed erupted, alkali-washed unerupted and unwashed unerupted at the outer most enamel (approx. 6 microns). However the erupted enamel (alkali-washed or not) showed higher F levels than unerupted enamel (alkali-washed or not) between approx. 6 microns and greater than 100 microns. The increase of F for this high-F area was about 100% in the deeper enamel while for a low-F area it was approx. 78% in the most outer enamel with no increase after a depth of about 20 microns. In contrast to a similar low-F area (water F < 0.10 parts/10(6)), no significant 'CaF2-like' F could be detected in erupted or unerupted enamel for the high-F area.
Oral and Dental Research Institute, Faculty of Dentistry, University of Stellenbosch, Tygerberg, South Africa.
S R
SR
Grobler
J F
JF
van Zyl
I
I
Stander
T J
TJ
Kotze
D003743:Dental Enamel / Q000737:chemistry / Q000378:metabolism*; D005457:Fluoridation; D005459:Fluorides / Q000032:analysis / Q000493:pharmacokinetics*; D009050:Fluorosis, Dental / Q000209:etiology / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides; D008964:Molar, Third / Q000378:metabolism; D017680:Potassium Compounds; D012995:Solubility; D018709:Statistics, Nonparametric; D014097:Tooth, Unerupted / Q000737:chemistry / Q000378:metabolism*; D014100:Toothpastes
D006878:Hydroxides; D017680:Potassium Compounds; D014100:Toothpastes; D005459:Fluorides; C029943:potassium hydroxide