Biomechanical Research Group, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
Int Endod J. 2012 Feb;45(2):136-45. doi: 10.1111/j.1365-2591.2011.01953.x. Epub 2011 Oct 13.
To evaluate the effect of luting agent and fibreglass post design on bond strength to root dentine at different depths within the canal.
Ninety single-rooted teeth were root filled and prepared to receive either a parallel-sided and serrated fibreglass post (Reforpost no. 2) or a tapered and smooth fibreglass post (Exato Cônico). The posts were cemented with the following resin cements: dual-cured resin cement (Rely X ARC), two self-adhesive resin cements (Rely X Unicem and MaxCem) and a self-cured resin cement (Cement-Post). The roots were cross-sectioned to obtain two 1-mm-thick discs for each cervical, middle and apical third of the prepared root portion. The posts were submitted to a micropush-out test at a speed of 0.5 mm min(-1), and the bond strength values (MPa) were submitted to anova in a split-plot arrangement and Tukey's test (P < 0.05).
The RelyX Unicem demonstrated significantly higher bond strength values (P < 0.001) along the root dentine. The RelyX ARC and Cement-Post had similar bond strength values in the cervical third; however, the bond strength decreased significantly (P < 0.001) in an apical direction for the RelyX ARC. Significantly lower bond strength values (P < 0.001), irrespective of canal region, were found for MaxCem cement. The bond strength was similar for both post configurations irrespective of the resin cement and canal region.
The retention of glass fibre posts remained unaffected by surface roughness but was influenced by resin cement type. The self-adhesive cement RelyX Unicem yielded a significantly greater (P < 0.001) bond strength value when cementing the fibreglass posts.
评估不同根管深度的黏结剂和纤维桩设计对牙本质黏结强度的影响。
90 颗单根牙进行根管填充和预备，以接收平行侧和锯齿纤维桩（Reforpost no. 2）或锥形和平滑纤维桩（Exato Cônico）。使用以下树脂水门汀黏固纤维桩：双固化树脂水门汀（Rely X ARC）、两种自黏结树脂水门汀（Rely X Unicem 和 MaxCem）和自固化树脂水门汀（Cement-Post）。将牙根切成 1mm 厚的薄片，每个薄片取自预备牙根的颈、中、根尖三分之一。以 0.5mm/min 的速度将纤维桩进行微推出试验，将黏结强度值（MPa）进行分割区组方差分析和 Tukey 检验（P<0.05）。
RelyX Unicem 在牙本质中表现出显著更高的黏结强度值（P<0.001）。RelyX ARC 和 Cement-Post 在颈三分之一处具有相似的黏结强度值；然而，RelyX ARC 在根尖方向的黏结强度显著降低（P<0.001）。MaxCem 水门汀的黏结强度显著降低（P<0.001），与根管区域无关。两种纤维桩构型的黏结强度在不同树脂水门汀和根管区域均相似。
纤维桩的保留不受表面粗糙度的影响，但受树脂水门汀类型的影响。黏固纤维桩时，自黏结水门汀 RelyX Unicem 产生显著更高的黏结强度值（P<0.001）。
