EFFECTS OF DIETARY OIL CONTAMINATION AND ABSENCE OF PROPHYLAXIS ON ORTHODONTIC BONDING

The effect of contamination by dietary oil on acid etching has not bee n reported in the literature. If dietary oil adversely affects acid et ching, then a decrease in bond strength is expected. This in vitro stu dy investigated the bond strength of brackets bonded to tooth surfaces that had been contaminated with dietary oil and on which prophylaxis was not carried out. The mean shear bond strengths for the control, te eth with oil contamination and teeth with oil contamination but no pro phylaxis undertaken were 53.33 +/- 14.31 (SD), 61.76 +/- 19.32 and 64. 12 +/- 17.09 N, respectively. An analysis of variance (ANOVA) test sho wed that there was no significant difference between the three groups. The power of the ANOVA was calculated for the minimum clinical change that would be worth detecting and was found to be approximately 1.0. It can therefore be concluded that the presence of dietary oil on the tooth surface does not adversely affect shear bond strength, even if p rophylaxis is not carried out. Bond failures for all three groups occu rred mainly at the tooth-adhesive interface.