Khamverdi Zahra, Damavandi Leila Yazdani, Kasraei Shahin
Associate Professor, Member of Dental Research Center, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran.
Assistant Professor, Operative Dentistry Department, Dental School, Gorgan University of Medical Sciences, Golestan, Iran.
J Dent (Tehran). 2014 Jan;11(1):85-92. Epub 2014 Jan 31.
The aim of this study was to evaluate the effect of cyclic loading on the bond strength of quartz fiber posts to root canal dentin after different surface treatments of different regions of root canal dentin.
Forty-eight single-rooted human teeth were selected. Post spaces were prepared and then the teeth were divided into four groups: G1: no treatment (control); G2: irrigation with a chemical solvent; G3: etching with 37% phosphoric acid; G4: treatment with ultrasonic file. The fiber posts were cemented using dual-cured resin cement. Half of the specimens were load-cycled (10000 cycles, 3 cycles/s) and the others did not undergo any load cycling. From each root, two slides measuring 1 mm in thickness were obtained from the apical and cervical regions. The push-out bond strength test was performed for each slice. Data were analyzed by using 3-way ANOVA and Tukey HSD tests. The fracture modes were evaluated under a stereomicroscope at ×20.
The effect of load cycling and surface treatment as the main factors and the interaction of main factors were not significant (P=0.734, P=0.180, and P=0.539, respectively). The most frequent failure mode under the stereomicroscope was adhesive.
It appears that load cycling and surface treatment methods had no effect on the bond strength of fiber posts to root canal dentin, but it depended on the region of the root canal dentin.
本研究旨在评估根管牙本质不同区域经不同表面处理后，循环加载对石英纤维桩与根管牙本质粘结强度的影响。
选取48颗单根人牙。制备桩道后，将牙齿分为四组：G1：不做处理（对照组）；G2：用化学溶剂冲洗；G3：用37%磷酸酸蚀；G4：用超声锉处理。使用双固化树脂水门汀粘结纤维桩。一半标本进行循环加载（10000次循环，3次/秒），另一半不进行任何循环加载。从每个牙根的根尖和颈部区域获取两片厚度为1mm的切片。对每片切片进行推出粘结强度测试。数据采用三因素方差分析和Tukey HSD检验进行分析。在体视显微镜下以×20放大倍数评估断裂模式。
循环加载和表面处理作为主要因素的影响以及主要因素之间的相互作用均不显著（P分别为0.734、0.180和0.539）。在体视显微镜下最常见的失效模式是粘结性失效。
循环加载和表面处理方法似乎对纤维桩与根管牙本质的粘结强度没有影响，但这取决于根管牙本质的区域。
