The effect on the tensile bond strength of orthodontic brackets of titanium tetrafluoride (TiF4) application after acid etching.

Titanium tetrafluoride (TiF4) was applied to acid-etched enamel surfaces to study the effect on surface structure and tensile bond strength of orthodontic brackets. Three groups of 20 premolars each were compared in debonding tests. Group I received a 1% and Group II received a 4% topical TiF4 treatment after acid etching. Group III served as control, that is, no fluoride solution was applied to the enamel after acid etching. Each treatment lasted 60 seconds followed by a thorough rinsing with water for 30 seconds. Brackets were bonded on all teeth with the same procedure. All premolars were then placed in a water bath at 37 degrees C. Ten teeth from each group were debonded after 24 hours, and the remaining teeth were debonded after 6 months. Results indicated that the application of 1% and 4% TiF4 solutions on etched enamel surfaces did not alter the tensile bond strength significantly after 24 hours and 6 months. The scanning electron microscope (SEM) examination of the surface structure demonstrated the presence of extensive reaction products, which covered enamel surfaces and appeared to interfere with etch patterns. It was concluded that the application of TiF4 solutions to etched enamel surfaces before bonding will not have an adverse effect on the tensile strength of orthodontic attachments.