복합레진 접착력의 레이저 영향에 관한 연구 = A Study on the Effect of Laser to the Bond Strength of Composite Resin

다국어 초록 (Multilingual Abstract)

The purpose of this study was investigating the shear bond strength between posterior composite resin and enamel surface of the permanent premolar.
The enamels of sound permanent premolars extracted for orthodontic therapy were used for experiment. They were classified into 6 groups at random ; 2 Clearfil self-cured resin groups and 2 P-50 light-cured resin groups and 2 Clearfil light-cured resin groups which have lased group and unlased group each other.
Laser impacts on each experimental groups were made at energy density of Pulsed Nd : YAG laser with 40 J/㎠.
Then the decalcified patterns of enamel by 37% phosphoric acid and resin tags of each group were investigated with scanning electron microscope and adhesive shear bond strength was measured on the each decalcified enamel surface after adhesion of light-cured and self-cured resins.
The obtained results were as follows.
1. There were significant increase in shear bond strength of Clearfil light-cured resin groups and Cleafil self-cured resin groups in contrast to P-50 light-cured resin groups at significant level α=0.05 in unlased condition(P<0.05).
2. There were not significant difference statistically between the groups but increased order in shear bond strength was ; Clearfil self-cured resin groups, Clearfil light-cured resin groups, P-50 light-cured resin groups in lased condition(P>0.05).
3. In case of P-50 light-cured resin groups, there was significant increase of shear bond strength at significant level α=0.01 after laser irradiation(P<0.01). In case of Clearfil light-cured resin and Clearfil self-cured resin groups, there was increase of shear bond strength but not significant statistically at significant level α=0.05 after laser irradiation(P>0.05).
4. There were significant increase in shear bond strength of Clearfil light-cured resin groups and Clearfil self-cured resin groups in contrast to P-50 light-cured resin groups at significant level α=0.05 in all groups(P<0.05).
5. The sample of high shear bond strength had many resin tags were deep and uniform penetration and the resin tags had many small tags in contrast to the sample of low shear bond strength.