A STUDY OF THE EFFECT OF LOW INTENSITY INITIAL LIGHT CURING ON THE BOND STRENGTH OF RESIN RESTORATION |
|
초기 저광도 광중합이 레진 수복물의 결합강도에 미치는 영향에 관한 연구 |
한미란, 권순원, 김종수 |
단국대학교 치과대학 소아치과학교실 |
|
|
Abstract |
Recently some studies have shown that low light intensity followed by final cure at high light intensity may result in a smaller marginal gap and may be no negative effect on material properties. The purpose of this study was to evaluate the influence of the initial cure with low intensity on the shear bond strength of dentin and the microhardness of composite resin. Twenty intact bovine teeth were prepared for shear bond strength test and each tooth sectioned to three specimens. The specimens were randomly divided into three groups according to the light intensity and curing time as follows; Group I. 450mmW/cm2 40sec Group II. 300mmW/cm2 20sec and 600mmW/cm2 20sec Gropu III. 250mmW/cm2 20sec and 450mmW/cm2 20sec. Samples of each group were restored with light-cured composite resin after dentin bonding and then the shear bond strength of each specimen were measured using universal testing machine. Ten resin specimens per group were prepared. After 24 hours, the Vickers microhardness value was measured at the top and bottom surfaces. The result are as follows; 1. Mean value of low initial intensity groups(II, III) were higher than the control group(I) in shear bond strength, but no significant difference could be found. 2. No significant difference could be found between three groups in microhardness. |
Key Words:
Low initial intensity, Shear bond strength |
|