The effect of 4% titanium tetrafluoride solution on root canal walls--a preliminary investigation

The aim of the present study was to evaluate the effect of 4% titanium tetrafluoride (TiF4) solution on root canal walls by scanning electron microscopy. Twenty four root canals with or without a smear layer were treated with 4% TiF4 solution. Scanning electron microscopic observation of the smeared canal walls showed that TiF4 solution modified the smear layer and produced a massive structure. In smear-free group, a granular coating was formed on intertubular and intratubular dentin. The stability of this layer was tested further with EDTA and/or NaOCl irrigations on 20 additional specimens. It was observed that none of the solutions was able to remove this modified smear layer. These results may indicate that this extremely stable structure may be advantageous in endodontics, because it can prevent further infection of root canal dentin by sealing off the tubules permanently, and can reduce microleakage by preventing further dissolution and disintegration of the smear layer.