تاثیر روشهای تراش حفره و نوع ماده ادهسیو بر تطابق لبه ای در مارژین سرویکالی حفرات کلاس II کامپوزیتی

Abstract

[بدون چکیده]

Introduction: One of the challenges in durability of posterior tooth-colored restorative materials is the shrinkage generated during polymerization reaction causing stress and gap between restoration and tooth. Bacteria and fluids present at this interface and compromise the durability of restoration. Objectives: The aim of the present study was to investigate the marginal adaptation of the ClII composite restorations using two etch & rinse and a self- etch adhesive systems in cavities prepared either with bur or Er.Cr.YSGG laser and. Methods and materials: A total of 45 sound human premolars were selected. In each tooth mesial and distal ClII cavities were prepared either by diamond instrument or Er.Cr.YSGG laser with the margins 1mm above the CEJ. Then the teeth were randomly divided into three groups each of 15 according to the type of adhesive syetem (Single Bond, Single Bond2 and Adper Easy One adhesive systems). To simulate the clinical stress, the specimens were subjected to thermal cycling at (5±2) ± (55±2) ˚C total of 500 cycles. The teeth were then cut longitudinally (mesiodistally) into two halves using a diamond disk mounted on a handpiece with water cooling. Marginal adaptation was evaluated using stereomicroscope and the values for gap width were obtained in micrometer. The data was analyzed using the SPSS statistical package. Two Factor ANOVA test were used. Results: the results demonstrated that there was statistically significant difference in mean marginal gap width between adhesive and preparation groups (P<0.05). Conclusion: The mean interfacial gap width in bur-prepared cavities is significantly less than laser prepared cavities and the lowest gap width was observed in Adper Easy One.