In situ effect of titanium tetrafluoride and sodium fluoride on artificially decayed human enamel.

This study compared in situ the application of 4% titanium tetrafluoride (TiF4) solution and 2% sodium fluoride (NaF) gel on artificial white-spot lesions in human enamel. A crossover, double-blind study using in situ caries models was carried out. Eleven volunteers used an intraoral appliance containing five demineralized human enamel blocks. The blocks (n=170) were randomly divided according to treatment into the following groups: TiF4 (n=55), NaF (n=55), positive control (n=55). A negative control group was composed of demineralized specimens (n=5). The microhardness test was performed using a Knoop penetrator. Energy dispersive spectrometer (EDS) was used to analyze the concentration of titanium, calcium, phosphate and oxygen. The enamel microhardness at different depths for TiF4, NaF and positive control samples was not statistically different (p>0.05). The samples from these three groups had statistically higher microhardness values than the negative control samples (p<0.05). EDS analysis did not provide conclusive results about the penetration of titanium in the TiF4 samples. While in some fragments it had substantial penetration, in other fragments it only had superficial penetration. It was possible to conclude that, under in situ conditions, 4% TiF4 solution and 2% NaF gel were able to remineralize artificial white-spot lesions in human enamel. However, the magnitude of the remineralization did not differ between groups.