Korean J Orthod.  2010 Apr;40(2):87-94. 10.4041/kjod.2010.40.2.87.

Modified laser etching technique of enamel for bracket bonding

• Yun MS
• Lee SM
• Yang BH

• KMID: 2273216
• DOI: http://doi.org/10.4041/kjod.2010.40.2.87

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.
CONCLUSIONS
To obtain maximum shear bonding strength, a combined technique of Er,Cr:YSGG and 37% phosphoric acid is useful even though it may be inconvenient.

Keyword

Laser; Etching; Acid etching; Shear bond strength

MeSH Terms

Adhesives
Bicuspid
Chromium
Dental Enamel
Erbium
Phosphoric Acids
Adhesives
Chromium
Erbium
Phosphoric Acids

Figure

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  Fig. 1 Mounting state on universal testing machine (UTM) and Force direction.

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  Fig. 2 Means and standard deviations of the bond strengths for each group. 1, 37% phosphoric acid; 2, laser etching + phosphoric acid; 3, phosphoric acid + laser etching; 4, laser etching.

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  Fig. 3 SEM images of enamel surface. A, 37% phosphoric acid (× 1,500); B, Laser etching + phosphoricacid (× 1,700); C, Phosphoric acid + laser etching (× 1,600); D, Laser etching (× 1,800).

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