Abstract
Objective
Many studies have carried out research on comparisons between laser etching and conventional etching systems to investigate methods of reinforcing shear bond strength. The purposes of this study were to assess the efficiency of bonding with erbium, chromium doped: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser etching combined with the conventional etching technique.
Methods
Sixty-four sound premolars, extracted for orthodontic purposes, were randomly divided into 4 groups and treated in the following manner. First group, conventional etching of 37% phosphoric acid for 15 seconds (control); second group, 1.5 W laser etching for 10 seconds followed by conventional etching; third group, conventional etching followed by 1.5 W laser etching; fourth group, 1.5 W laser etching for 15 seconds only. We assessed the shear bond strength, the surface characteristics, and the adhesive remnant index scores between all groups.
Results
Experimental groups showed higher shear bond strength than the control group. But no statistically significant differences were found between the second and third groups. Adhesive remnant scores were compared with the Kruskal-Wallis test, and no statistically significant differences were found between all groups.
Figures and Tables
Table 2
*Adhesive remnant index scores were: 1, All adhesive remaining on the tooth; 2, more than 90% of the adhesive remaining on the tooth; 3, more than 10% but less than 90% of the adhesive remaining on the tooth; 4, less than 10% of the adhesive remaining on the tooth; 5, no adhesive remaining on the tooth (p < 0.05).
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