Water and Saliva Contamination Effect on Shear Bond Strength of Brackets Bonded with a Moisture-Tolerant Light Cure System

Objective: To evaluate the effects of water and saliva contamination on shear bond strength of brackets bonded with a moisture-tolerant light cure system. Materials and Methods: Brackets were bonded to 240 bovine lower incisors divided into 12 groups. Four bonding procedures were evaluated, including (1) TSEP/Transbond XT, (2) TMIP/ Transbond XT, (3) TSEP/Transbond PLUS, and (4) TMIP/Transbond PLUS, each under three different bonding conditions: without contamination, with water contamination, and with saliva contamination. Shear bond strength was measured with a universal testing machine. The adhesive remnant on the teeth was quantified with the use of image analyzing equipment. Results: Without contamination, bond strengths for the four procedures were similar (P > .05). TSEP/Tranbond PLUS and TMIP/Transbond PLUS left significantly less adhesive on the teeth after debonding than TSEP/Transbond XT and TMIP/Transbond XT (P < .008). Bond strength and adhesive remaining for TMIP/Transbond XT contaminated with water or saliva showed significantly worse performance than the other procedures evaluated (P < .008). Contamination (with water or saliva) did not affect either bond strength or adhesive remaining on the teeth for TSEP/ Transbond XT, TSEP/Transbond PLUS, or TMIP/Transbond PLUS (P > .017), although for TMIP/ Transbond XT, both variables showed significant reductions after contamination (P < .017). Conclusion: TSEP/Transbond PLUS, TMIP/Transbond PLUS, and TSEP/Transbond XT showed greater tolerance to wet conditions than was shown by TMIP/Transbond XT.