Di Fiore Peter M, Reyes Adrian, Dorn Samuel O, Cron Stanley G, Ontiveros Joe C
Professor, Department of Endodontics, University of Texas, School of Dentistry, Houston, Texas.
Resident, Department of Endodontics, University of Texas, School of Dentistry, Houston, Texas.
J Prosthet Dent. 2016 Jan;115(1):35-41. doi: 10.1016/j.prosdent.2015.07.003. Epub 2015 Sep 26.
Fractures of endodontically treated teeth have been attributed to weakened tooth structure caused by root canal enlargement and post preparation.
The purpose of this in vitro study was to evaluate the fracture resistance of roots filled with either gutta percha, composite resin (LuxaCore Dual), or calcium silicate-based cement (Biodentine).
One hundred twenty freshly extracted, human, permanent maxillary anterior teeth were sorted by type and assigned to 1 of 4 groups (n=30). The teeth in group NT were not endodontically treated and served as the control. The teeth in groups GP, LC, and, BD were accessed and instrumented to size 40/06. In group GP, the root canals were completely filled with gutta percha. In groups LC and BD, only the apical 5-mm portion of the root canals was filled with gutta percha, and the remaining portion of the root canals was filled with (LuxaCore Dual) in group LC and with (Biodentine) in group BD. Fracture resistance (kN) was assessed at the middle portion of each root, using a 3-point bending test with a universal testing machine exerting a compressive load on a loading pin at a crosshead speed of 0.5 mm/min until fracture occurred. One-way ANOVA was used to compare the mean root fracture resistance among the 4 groups (α=.05).
The mean ± SD fracture loads were 2.13 ±0.53 kN for group NT, 1.97 ±0.60 kN for group GP, 2.18 ±0.71 kN for group LC, and 2.22 ±0.54 kN for group BD. No statistically significant differences were found among the 4 groups (P>.05).
The roots of endodontically treated maxillary anterior permanent incisors filled with gutta percha, Biodentine, or LuxaCore Dual had resistance to fracture similar to that of teeth that were not endodontically treated.
根管治疗后的牙齿发生骨折被认为是由于根管扩大和桩道预备导致牙体结构削弱所致。
本体外研究的目的是评估用牙胶、复合树脂（LuxaCore Dual）或硅酸钙基水门汀（Biodentine）充填的牙根的抗折性。
将120颗新鲜拔除的人上颌前磨牙按类型分类，分为4组（每组n = 30）。NT组的牙齿未进行根管治疗，作为对照组。GP组、LC组和BD组的牙齿开髓并预备至40/ 06号。GP组根管完全用牙胶充填。LC组和BD组仅根管根尖5mm部分用牙胶充填，LC组根管其余部分用（LuxaCore Dual）充填，BD组用（Biodentine）充填。使用万能试验机以0.5mm/min的十字头速度对加载销施加压缩载荷直至骨折发生，在每个牙根的中部评估抗折性（kN）。采用单因素方差分析比较4组之间的平均牙根抗折性（α = 0.05）。
NT组的平均 ± 标准差骨折载荷为2.13 ± 0.53 kN，GP组为1.97 ± 0.60 kN，LC组为2.18 ± 0.71 kN，BD组为2.22 ± 0.54 kN。四组之间未发现统计学显著差异（P>0.05）。
用牙胶、Biodentine或LuxaCore Dual充填的根管治疗后的上颌前磨牙牙根的抗折性与未进行根管治疗的牙齿相似。
