Universidade Estadual de Campinas - Unicamp, Piracicaba Dental School , Department of Restorative Dentistry , Piracicaba , SP , Brazil .
University of Florida , College of Dentistry , Department of Restorative Dental Sciences , Gainesville , FL , USA .
Braz Oral Res. 2022 Jun 10;36:e075. doi: 10.1590/1807-3107bor-2022.vol36.0075. eCollection 2022.
This study aimed to evaluate the effect of light attenuation through ceramic veneers and resin cement on degree of conversion (DC), cohesive strength (CS), and microshear bond strength (μSBS) of experimental adhesive systems. Experimental etch-and-rinse and self-etch adhesives were combined with different ratios of camphorquinone (CQ) and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiators: CQ-only; 3CQ:1TPO; 1CQ:1TPO; 1CQ:3TPO and TPO-only. Square-shaped ceramic veneer (IPS Empress Esthetic, Ivoclar Vivadent) (n = 10; 10mm long x 10mm wide x 0.5mm thick) and resin cement specimens (Variolink Esthetic LC, Ivoclar Vivadent) (n = 10; 10 mm long x 10 mm wide and 0.3 mm thick) were prepared. Light transmittance of a multiple-peak LED (Bluephase G2, Ivoclar Vivadent) was measured through restorative materials using a spectrometer (n = 5). Adhesive specimens were analyzed for DC, CS, and μSBS by light-curing the adhesive with or without (control) ceramic veneer, and with resin cement fixed to output region of the light-curing tip (n = 10). Data were submitted to ANOVA and Tukey's test (α = 0.05). Total light transmittance through the restorative materials was attenuated, and this attenuation was more evident for the violet spectrum. The DC for the TPO groups in ratios up to 1CQ:1TPO was similar to the control. 1CQ:3TPO showed lower values for CS. μSBS was reduced for all groups with light attenuation, but lower values were observed for 1CQ:3TPO and TPO-only. In conclusion, light transmission was reduced with interposed restorative materials. Adhesives combined with CQ and TPO up to 1CQ:1TPO showed greater cure efficiency and mechanical properties compared with a higher amount of TPO.
本研究旨在评估通过陶瓷贴面和树脂水门汀的光衰减对实验性粘接系统的转化率（DC）、内聚强度（CS）和微剪切结合强度（μSBS）的影响。实验性酸蚀-冲洗和自酸蚀粘接剂与不同比例的樟脑醌（CQ）和二苯基（2,4,6-三甲基苯甲酰）氧化膦（TPO）光引发剂组合使用：仅 CQ；3CQ:1TPO；1CQ:1TPO；1CQ:3TPO 和 TPO 仅。制备方形陶瓷贴面（IPS Empress Esthetic，Ivoclar Vivadent）（n = 10；10mm 长 x 10mm 宽 x 0.5mm 厚）和树脂水门汀标本（Variolink Esthetic LC，Ivoclar Vivadent）（n = 10；10mm 长 x 10mm 宽 x 0.3mm 厚）。使用分光光度计测量多峰 LED（Bluephase G2，Ivoclar Vivadent）透过修复材料的光透射率（n = 5）。将粘合剂样本用光固化，或不用（对照）陶瓷贴面，用光固化尖端的输出区域固定树脂水门汀（n = 10），分析其 DC、CS 和 μSBS。数据提交进行方差分析和 Tukey 检验（α = 0.05）。修复材料的总透光率降低，紫光谱的衰减更为明显。在高达 1CQ:1TPO 的 TPO 比例下，TPO 组的 DC 与对照相似。1CQ:3TPO 的 CS 值较低。所有经过光衰减的组的 μSBS 均降低，但 1CQ:3TPO 和 TPO 仅的 μSBS 较低。总之，中间放置修复材料会降低光传输。与更高量的 TPO 相比，与 CQ 和 TPO 结合的粘合剂在高达 1CQ:1TPO 的比例下显示出更高的固化效率和机械性能。
