Kiomarsi Nazanin, Espahbodi Melika, Chiniforush Nasim, Karazifard Mohammad Javd, Kamangar Sedighe Sadat Hashemi
Department of operative dentistry, Dental school, Tehran University of Medical Sciences, International campus, Tehran, Iran.
Tehran University of Medical Science, International campus, Tehran, Iran.
Laser Ther. 2017 Sep 30;26(3):173-180. doi: 10.5978/islsm.17-OR-12.
This study aimed to assess the effect of surface treatment by bur and laser and application of universal adhesive on repair bond strength of composite resin.
A total of 120 composite blocks measuring 6×4×4 mm were fabricated of Filtek Z250 composite. All samples were subjected to 5,000 thermal cycles and divided into two groups for surface preparation by bur and by Er,Cr:YSGG laser (n = 60). The surfaces were then etched with orthophosphoric acid, rinsed with water and divided into three groups (silane, silane plus Single Bond and silane plus Single Bond Universal). Repair composite was then bonded to aged composite. Half of the samples in each group were stored in distilled water at 37°C for 24 hours and the other half underwent 5000 thermal cycles. All samples were then subjected to shear bond strength testing using a universal testing machine at a crosshead speed of 1 mm/minute. The data were analyzed using one-way ANOVA and Tukey's HSD test. Mode of failure was determined using a stereomicroscope.
Bur preparation plus universal adhesive yielded the highest bond strength (30.16 µ 2.26 MPa). Laser plus silane yielded the lowest bond strength (5.63 µ 2.43 MPa). Bur preparation yielded significantly higher bond strength than laser (P < 0.001). Also, application of universal adhesive significantly improved bond strength compared to conventional adhesive and silane (P < 0.001). Bond strength after aging (5000 thermal cycles) had no significant difference with primary bond strength at 24 hours within each group (P = 0.182).
Surface preparation of aged composite by bur and application of universal adhesive can improve the repair bond strength of composite. Application of silane (without adhesive) in the process of repair cannot provide adequately high repair bond strength.
本研究旨在评估用牙钻和激光进行表面处理以及应用通用型黏结剂对复合树脂修复黏结强度的影响。
用Filtek Z250复合树脂制作120个尺寸为6×4×4mm的复合树脂块。所有样本均经历5000次热循环，然后分为两组，分别用牙钻和Er,Cr:YSGG激光进行表面处理（每组n = 60）。接着用正磷酸对表面进行酸蚀，用水冲洗，再分为三组（硅烷组、硅烷加Single Bond组和硅烷加Single Bond Universal组）。然后将修复用复合树脂黏结到老化的复合树脂上。每组样本的一半在37℃蒸馏水中储存24小时，另一半再经历5000次热循环。之后使用万能试验机以1mm/分钟的十字头速度对所有样本进行剪切黏结强度测试。数据采用单因素方差分析和Tukey's HSD检验进行分析。使用体视显微镜确定失败模式。
牙钻处理加通用型黏结剂产生的黏结强度最高（30.16 µ 2.26 MPa）。激光处理加硅烷产生的黏结强度最低（5.63 µ 2.43 MPa）。牙钻处理产生的黏结强度显著高于激光处理（P < 0.001）。此外，与传统黏结剂和硅烷相比，通用型黏结剂的应用显著提高了黏结强度（P < 0.001）。每组中老化后（5000次热循环）的黏结强度与24小时时的初始黏结强度无显著差异（P = 0.182）。
用牙钻对老化复合树脂进行表面处理并应用通用型黏结剂可提高复合树脂的修复黏结强度。在修复过程中单独应用硅烷（无黏结剂）无法提供足够高的修复黏结强度。
