ผลของการปรับสภาพพื้นผิววัสดุเรซินคอมโพสิตชนิดเสริมความแข็งแรงด้วยไฟเบอร์เส้นสั้นที่ผ่านการตัดแต่งต่อค่าความแข็งแรงยึดเฉือนและความคงทนของการยึดติดเมื่อทำการยึดติดด้วยเรซินซีเมนต์

Abstract

Introduction: Biomimetic dentistry becomes the cornerstone in the development of restorative materials, which mimic the natural tooth’s characteristics including mechanical, physical, and optical properties. The short fiber-reinforced resin composite (SFRCs) has been used as core build up in severely damaged teeth. SFRCs were presented the denuded fiber exposure and no oxygen inhibited layer after tooth preparation process for indirect restoration, these might inhibit adhesion to resin cement. There was no evidence about SFRCs bonding capacity to resin cement after tooth and core material preparation. Purpose: To evaluate the effect of surface treatment on shear bond strength (SBS) and bond durability between prepared SFRCs and self-adhesive resin cement. Methods: 20 conventional resin composites blocks (filtekTMZ350XT, FT) and 80 SFRCs blocks (everX posteriorTM, EV) with a dimension of 5 mm diameter and 4 mm height, were cross sectioned at middle to obtained 200 resin composite discs (5 mm diameter, 2 mm height) with a cut surface. The resin composite discs were embedded in epoxy resin with exposed the cut surface then polished and stored in distilled water at 37°C for 7 days. The 40 FT specimens were used as control group and 160 EV specimens were randomly divided into 4 groups according to surface treatments methods: no treatment (EV1), silanization (EV2), sandblasting (EV3) and sandblasting with silanization (EV4). Specimens were cemented with resin composite rods (3 mm diameter, 2 mm height) using the self-adhesive resin cement (RelyXTMUnicem) then divided into 2 subgroups; 1) water storage for 24 hours, 2) water storage for 24 hours and thermocycling 10,000 cycles. All specimens were subjected to SBS test. Data were analyzed by Two-way ANOVA and Tukey’s test. Modes of failure were observed by stereomicroscope. Result: The SBS of EV groups was significantly higher than that of FT group (p<0.05). After thermocycling, the SBS was significantly decreased in all group except EV2 (p<0.05). Failure mode analysis showed predominantly mixed failure in EV2, EV3, EV4 and adhesive failure in FT, EV1. Conclusion: SFRCs presented higher SBS to the self-adhesive resin cement than that of conventional resin composite. All of surface treatments of prepared SFRCs resulted in increasing SBS to self-adhesive resin cement. The silanization of prepared SFRCs presented highest bond durability.