Postgraduate student, School of Dentistry, University of Ribeirão Preto, São Paulo, Brazil.
Doctoral student, School of Dentistry, University of Ribeirão Preto, São Paulo, Brazil.
J Prosthet Dent. 2018 Jan;119(1):97-102. doi: 10.1016/j.prosdent.2017.01.013. Epub 2017 Apr 28.
A major issue related to the failure of endodontically treated teeth restored with an intraradicular post is gradual debonding of the glass fiber post, resin cement, and dentin.
The purpose of this in vitro study was to evaluate the influence of laser irradiation on the push-out bond strength of glass fiber posts to radicular dentin.
Thirty-two mandibular bovine incisors were endodontically treated and divided into 4 groups according to the surface treatment of the post: silane control (GC); irradiation with Er:YAG (GYAG); irradiation with Er,Cr:YSGG (GCR); and 980-nm diode laser (GDI) application. After surface treatment, the glass fiber posts were cemented with dual adhesive resin cement. To evaluate bond strength, the specimens were subjected to a push-out test at a crosshead speed of 0.5 mm/min using a universal testing machine. Failure mode was analyzed using stereomicroscopy. The surface morphology was evaluated qualitatively after surface treatment by using confocal laser microscopy. The push-out test data (MPa) were analyzed using a linear mixed effects model and the Bonferroni test (α=.05).
At the cervical third, no significant differences were observed between the GC and GCR groups (P=1.00), and both of the groups exhibited higher bond strength. At the middle and apical thirds, the GCR group revealed higher bond strength, which was significantly different from that observed in all other groups (P<.05). No statistical differences were observed among the other tested protocols (GC, GYAG, and GDI groups; P=1.00). Adhesive failure was predominant in all groups.
Irradiation with Er,Cr:YSGG improved the bond strength of the cement-post-dentin interfaces.
与用根管内桩修复的牙髓治疗牙失败相关的一个主要问题是玻璃纤维桩、树脂水泥和牙本质的逐渐脱粘。
本体外研究的目的是评估激光照射对玻璃纤维桩与根管牙本质的推出粘结强度的影响。
32 颗下颌牛切牙进行根管治疗，并根据桩的表面处理分为 4 组：硅烷对照组（GC）；Er:YAG 激光照射组（GYAG）；Er,Cr:YSGG 激光照射组（GCR）；980nm 二极管激光应用组（GDI）。表面处理后，用双粘结树脂水泥粘结玻璃纤维桩。为了评估粘结强度，将标本在万能试验机上以 0.5mm/min 的十字头速度进行推出试验。使用体视显微镜分析破坏模式。用共聚焦激光显微镜对表面处理后的表面形貌进行定性评价。使用线性混合效应模型和 Bonferroni 检验（α=.05）分析推出试验数据（MPa）。
在颈三分之一处，GC 组和 GCR 组之间无显著差异（P=1.00），且两组粘结强度均较高。在中三分之一和根尖三分之一处，GCR 组的粘结强度较高，与其他所有组均有显著差异（P<.05）。其他测试方案（GC、GYAG 和 GDI 组）之间无统计学差异（P=1.00）。所有组均以黏附性破坏为主。
Er,Cr:YSGG 激光照射可提高粘结剂-桩-牙本质界面的粘结强度。
