The Effect of Surface Treatment on Bond Strength of Polycarbonate Bracket

Kim, Seok Pil; Kim, Nyeon Kyeong; Lee, Hyun Jung; Hwang, Hyeon Shik

Abstract

OBJECTIVE
The purpose of this study was to evaluate whether the bond strength of polycarbonate brackets can be increased through surface treatment.
METHODS
One hundred polycarbonate brackets (Alice) were bonded to bovine incisors with light-cured adhesive. The bracket bases were treated with one of three methods; sandblasting, plastic conditioner application, and combined treatment with sandblasting and plastic conditioner. The brackets without any surface treatment served as the control. The shear bond strength was tested with a universal testing machine, and failure pattern was assessed with the adhesive remnant index.
RESULTS
The shear bond strength in all experimental groups was higher than that of the control group (p < 0.001). The group treated with plastic conditioner after sandblasting showed statistically higher shear bond strength than the sandblasting only group (p < 0.05). The group treated with plastic conditioner after sandblasting showed higher shear bond strength than plastic conditioner only group, but the difference was not statistically significant.
CONCLUSION
The above results suggest that the surface treatments of polycarbonate bracket is mandatory to improve bond strength, and the most effective method is an application of plastic conditioner after sandblasting.