Effects of titanium tetrafluoride on human enamel.

Acid etch biopsy specimens of human enamel surfaces treated with a TiF4 solution have shown fluoride uptake to be significantly greater than in untreated surfaces, but less than that obtained with an APF solution of the same fluoride concentration. The TiF4 treated surfaces, however, do show a statistically significant reduction in the acid solubility of the enamel. The presence of acid-resistant coating was shown by SEM.