In our study during 1989-1990, the effects of fluoride (F) content on the remineralization of root surfaces were not clarified because F level of remineralizing solution was fixed at 3.0 ppm. To access the relationship between F level in solution and the degree of remineralization, demineralized root specimens with cementum were immersed in solutions at different F level (0.5, 1, 0, 2, 0 and 3, 0 ppmF : F05, F1, F2, F3 group) for 14 days without application of fluorides. Treatment with F free solution (FO) was also studied. The results were as follows ;
(1) Treatments with F containing solutions were significantly effective with relative mineral increments (against the mineral volume after demineralization), F05 : 6.4%, F1 : 7.6%, F2 : 9.2%, F3 : 10.0% and F3 : 13.9%, respectively. The mineral volume increments were remarkably depended on F level in solution and significant coefficient correlation (r=0.98, p<0.05) was observed.
(2) F contents in surface layer (depth : 0-15mum) after 14-day remineralization were F0 : 1, 700ppm, F05 : 5, 000ppm, F1 : 6, 600ppm, F2 : 7, 200ppm and F3 : 7, 400ppm, respectively. Group F05, F1, F2 and F3 showed significantly higher F contents than F0. Furthermore, F contents in deeper part (depth : 40-50mum) of F2 and F3 were also significantly higher than those of another groups.
Our previous findings in 1989-1990 were presented in the 40th Conference of the Japanese Society for Dental Health (September, 1991), and the main results obtained during 1989-1992 were published as a original paper in Journal of Dental Health (D. INABA : Vol. 42, p. 66-78, 1992).
In addition, we have developed the quantitative video-densitometry for the evaluation of mineral volume, and we now intend to publish the papers on the new methodology and its application.