Al-Tayyan Mouhammad H, Watts David C, Kurer Hans G, Qualtrough Alison J E
School of Dentistry, The University of Manchester, Manchester, United Kingdom.
J Prosthodont. 2008 Oct;17(7):532-7. doi: 10.1111/j.1532-849X.2008.00347.x. Epub 2008 Aug 26.
This study had two aims: (1) to compare the retention of a flexible directly placed fiber-bundle dowel system with that of a rigid prefabricated fiber-reinforced composite (FRC) dowel system, and (2) to determine the effect of decreasing the volume of luting cement around the flexible fiber-bundle dowels on the axial retention of the restorations.
Single-canal premolars (n = 36) were decoronated, cleaned, shaped, and prepared for both flexible and rigid dowels to a depth of 10 mm using a size 2 drill. The roots were then randomly allocated into three groups: Ia, Ib, and II (n = 12). Flexible fiber-bundle dowels were placed in groups Ia and Ib. These were available in three fiber-bundle diameters: small (0.9 mm), medium (1.2 mm), and large (1.5 mm). These bundles were luted in the root canals with Variolink II. The differences between Ia and Ib were in the ratio of the volume of fiber-bundles to the volume of luting cement and in the mode of application. Medium fiber-bundles were placed to the end of the preparation in groups Ia and Ib; however, in group Ia, a small diameter auxiliary bundle was placed, whereas in group Ib, a large-diameter auxiliary bundle was cut axially into strips of circa 0.2-mm thickness before being sequentially overlapped in placement. Roots in group II were restored with size 2 rigid prefabricated fiber dowels and luted with the light-cured cement provided by the manufacturer. After 24 hours of storage, axial tensile forces were applied to all luted dowels progressively to failure at 0.5 mm/min. Data were analyzed using a one-way analysis of variance (ANOVA) and the Bonferonni test.
The mean axial resistance forces (standard deviation [SD]) for groups Ia, Ib, and II were not statistically different at 166 (49), 157 (36), and 151 (44) N, respectively (p > 0.05).
There was no significant difference between the retention of the flexible fiber-bundle dowel system and that of the rigid prefabricated fiber dowel system. Decreasing the volume of luting cement around the flexible dowels did not have a significant effect on the axial retention of the restorations.
本研究有两个目的：（1）比较柔性直接放置纤维束桩系统与刚性预制纤维增强复合材料（FRC）桩系统的固位情况；（2）确定减少柔性纤维束桩周围粘结剂体积对修复体轴向固位的影响。
选取单根管前磨牙（n = 36），去除牙冠，清理、预备根管，使用2号钻将柔性和刚性桩的根管预备至10 mm深度。然后将牙根随机分为三组：Ia组、Ib组和II组（n = 12）。Ia组和Ib组放置柔性纤维束桩。这些桩有三种纤维束直径：小（0.9 mm）、中（1.2 mm）和大（1.5 mm）。这些纤维束用Variolink II粘结于根管内。Ia组和Ib组的区别在于纤维束体积与粘结剂体积的比例以及应用方式。Ia组和Ib组均将中等直径纤维束放置到预备根管的末端；然而，Ia组放置一根小直径辅助纤维束，而Ib组则将大直径辅助纤维束轴向切割成约0.2 mm厚的条带，然后在放置时依次重叠。II组的牙根用2号刚性预制纤维桩修复，并用制造商提供的光固化粘结剂粘结。储存24小时后，以0.5 mm/min的速度对所有粘结桩逐渐施加轴向拉力直至破坏。使用单因素方差分析（ANOVA）和Bonferonni检验分析数据。
Ia组、Ib组和II组的平均轴向阻力（标准差[SD]）分别为166（49）N、157（36）N和151（44）N，差异无统计学意义（p > 0.05）。
柔性纤维束桩系统与刚性预制纤维桩系统的固位情况无显著差异。减少柔性桩周围粘结剂的体积对修复体的轴向固位没有显著影响。
