Impacts of Conservative Endodontic Cavity on Root Canal Instrumentation Efficacy and Resistance to Fracture Assessed in Incisors, Premolars, and Molars
Impacts of Conservative Endodontic Cavity on Root Canal Instrumentation Efficacy and Resistance to Fracture Assessed in Incisors, Premolars, and Molars
复制标题
DOI：
10.1016/j.joen.2013.12.012
复制
发表时间：
2014-08-01
影响因子：
4.2
通讯作者：
Friedman, Shimon
中科院分区：
文献类型：
--
作者：
Krishan, Rajesh;Paque, Frank;Friedman, Shimon
简介：保守性牙髓腔 (CEC) 可以提高牙齿的抗折断能力，但会影响根管的安装。本研究评估了 CEC 对 3 种牙齿类型的两个变量的影响。方法：使用微型计算机断层扫描成像（20μm 分辨率）对拔除的完整上颌切牙、下颌前磨牙和磨牙（n = 20/型）进行成像，并将其分配到 CEC 组或传统牙髓腔 (TEC) 组（n = 10/组/型）。将最小 CEC 绘制在扫描图像上。使用 WaveOne 仪器（Dentsply Maillefer，Ballaigues，瑞士）使用 1.25% 次氯酸钠制备根管，并获得处理后的显微计算机断层扫描图像。使用独立样本 t 检验分析每种牙齿类型的未触及根管壁 (UCW) 和牙本质去除体积 (DVR) 的比例。将 60 颗装有仪器的牙齿和 30 颗完整牙齿（阴性对照，n = 10/型）在 Instron 万能试验机（Instron，Canton，MA）（1 mm/min）中加载至断裂，并使用单向方差分析和 Tukey 检验对数据进行分析。结果：与 TEC (36.7% +/- 17.2%) 相比，UCW 的平均比例仅在 CEC 磨牙的远中管中显着较高 (P < .04) (57.2% +/- 21.7%)。切牙（16.09 +/- 4.66 vs 23.24 +/- 3.38 mm(3)）、前磨牙（8.24 +/- 1.64 vs 14.59 +/- 4.85 mm(3)）和磨牙（33.37 +/- 67.71）的 CEC 平均 DVR 显着小于 TEC（P < .003）毫米（3））。前磨牙 (586.8 +/- 116.9 vs 328.4 +/- 56.7 N) 和磨牙 (1586.9 +/- 196.8 vs 641.7 + 62.0 N) 中 CEC 的平均断裂载荷显着高于 TEC (P < .05)。在两种牙齿类型中，CEC 与阴性对照没有显着差异。结论：虽然 CEC 仅与磨牙远中根管中根管器械受损的风险相关，但它保留了 3 种牙齿类型中的冠状牙本质，并具有增加下颌磨牙和前磨牙的抗骨折能力的益处。
Introduction: Conservative endodontic cavity (CEC) may improve fracture resistance of teeth but compromise the instrumentation of canals. This study assessed the impacts of CEC on both variables in 3 tooth types. Methods: Extracted human intact maxillary incisors, mandibular premolars, and molars (n = 20/type) were imaged with micro-computed tomographic imaging (20-mu m resolution) and assigned to CEC or traditional endodontic cavity (TEC) groups (n = 10/group/type). Minimal CECs were plotted on scanned images. Canals were prepared with WaveOne instruments (Dentsply Maillefer, Ballaigues, Switzerland) using 1.25% sodium hypochlorite and post-treatment micro-computed tomographic images obtained. The proportion of the untouched canal wall (UCW) and the dentin volume removed (DVR) for each tooth type was analyzed with the independent-samples t test. The 60 instrumented and 30 intact teeth (negative control, n = 10/type) were loaded to fracture in the Instron Universal Testing machine (lnstron, Canton, MA) (1 mm/min), and the data were analyzed with 1-way analysis of variance and the Tukey test. Results: The mean proportion of UCW was significantly higher (P < .04) only in the distal canals of molars with CEC (57.2% +/- 21.7%) compared with TEC (36.7% +/- 17.2%). The mean DVR was significantly smaller (P < .003) for CEC than for TEC in incisors (16.09 +/- 4.66 vs 23.24 +/- 3.38 mm(3)), premolars (8.24 +/- 1.64 vs 14.59 +/- 4.85 mm(3)), and molars (33.37 +/- 67.71 mm(3)). The mean load at fracture for CEC was significantly higher (P < .05) than for TEC in premolars (586.8 +/- 116.9 vs 328.4 +/- 56.7 N) and molars (1586.9 +/- 196.8 vs 641.7 + 62.0 N). In both tooth types, CEC did not differ significantly from the negative controls. Conclusions: Although CEC was associated with the risk of compromised canal instrumentation only in the molar distal canals, it conserved coronal dentin in the 3 tooth types and conveyed a benefit of increased fracture resistance in mandibular molars and premolars.