할로겐과 LED 광조사기의 중합모드에 따른 미세누출 비교

Abstract

The purpose of this study was to compare the microleakage of cervical resin composite restorations cured with different modes of halogen and LED light curing units. Sixty box-shaped class V cavities were prepared in extracted human molars with gingival margins located apical beyond the CEJ. Cavities were filled using Single Bond and hybrid resin composite, Z 250. Two types of light source, halogen (Optilux 501, Kerr, Orange, CA, USA) or LED light curing unit (Bluephase, Ivoclar/ Vivadent, Schaan, Liechtenstein) were used for curing the composite. Each curing unit was applied with three different curing modes (standard, ramp and high intensity curing mode). Thus the specimens were divided randomly into six groups of 10. After thermocyding between 5 and 55℃ for 500 cycles, the specimens were immersed in 2% methylene blue at 37℃ for 24 hours. The teeth were longitudinally sectioned with Diamond Wheel Saw and 3 cuttings per tooth were provided 6 surfaces for evaluation. The marginal dye penetration was recorded on a scale from 0 to 3 under the microscope. Kruskal-Wallis and Mann-Whitney tests were used for statistical analysis. There was no statistically significant difference of microleakage between light curing units at enamel margin. At gingival margin, the microkakage by LED light curing unit was significantly higher than by halogen light curing unit. Using high intensity curing mode, the difference of gingival microleakage between light curing units was not statistically significant. When comparing the microleakage obtained with different curing mode on halogen light curing unit, the gingival microleakage by ramp curing mode was significantly lower than by high intensity curing mode. When comparing the influence of different curing mode on LED light curing unit, no significant difference was shown. At gingival margin, the microleakage obtained with LED light curing unit was significantly higher than with halogen light curing unit. Stress relief by ramp curing mode of halogen light curing unit was achieved.