a significant increase in the f-concentrations in three enamel layers of the test-teeth was found as compared to the control-teeth : 1732 +/- 156 ( 884 +/- 101 ) , 904 +/- 82 ( 464 +/- 79 ) and 524 +/- 88 ( 296 +/- 24 ) ppm f .
C0011350
enamel
C0040426
teeth