IN-VITRO EVALUATION OF TOPICAL FLUORIDES FOR OVERDENTURE ABUTMENTS

Statement of problem. Topical fluorides are effective, yet none have b een developed specifically for root or dentin surfaces. Purpose. This study evaluated the ability of several commercial topical fluorides to protect overdenture abutments from in vitro acid demineralization. Ma terial and methods. Twenty extracted teeth from persons aged 50 to 70 years were prepared for overdenture abutments. The teeth were sectione d to provide 40 buccal and lingual halves, covered with nail varnish e xcept for windows on the occlusal and root surfaces, and randomly divi ded into 4 groups of 10 specimens, which were cycled for 6 hours in ac id demineralization, washed, and then held 17 hours in a remineralizin g solution for 18 days. Before each cycle, the specimens were treated with either Karigel, Karigel-N, or a NaF solution. The control group w as treated with fluoride-free solution. Results. The depth of the arti ficial lesions on the root surfaces showed a statistically significant dose response. On the occlusal, there were no differences in lesion d epth between the various topical fluorides and the control group. But there was a dose response when the remineralized band was subtracted f rom the lesion depth. Remineralization bands in the occlusal lesions w ere !lot evident in the control group, but were present in the fluorid e groups. Conclusion. This study suggests that higher concentrations o f NaF are more protective for overdenture abutments.