PDF(Pubmed)
Abstract：
UNASSIGNED: Dentinal microcracks formed during apical resection may lead to increased susceptibility to root fracture and improper sealing of apical preparation that may negatively influence the outcome of endodontic microsurgery.
UNASSIGNED: This study was performed to analyze the root-end surface for dentinal microcracks using a scanning electron microscope (SEM) after resection with high-speed bur and trephine drill.
UNASSIGNED: Thirty extracted single-rooted maxillary premolar teeth were selected and randomly distributed into two groups (n = 15). Working length was established using a #15 K-type file. Canals were prepared with a rotary Ni-Ti system to size 30/0.06 using endomotor, irrigated with 3% sodium hypochlorite, dried with paper points, and obturated with gutta-percha cones using a single-cone technique. All samples were mounted on preformed molds and poured using a mixture of sawdust and gypsum. In Group A; tungsten carbide bur was used to perform a freehand apicoectomy. In Group B; a trephine drill was used with a three-dimensional guide to perform 3 mm of root resection. Apicoectomy was performed in both groups under a dental operating microscope. Resected root ends were inspected for microcracks using SEM. The Shapiro-Wilk and Mann-Whitney U-test were used for statistical analysis.
UNASSIGNED: Microcracks were observed in all samples in both study groups. Trephine drill produced more microcracks on the resected root surface compared to the use of high-speed tungsten carbide bur with a statistically significant difference (P < 0.05).
UNASSIGNED: The trephine drill used during targeted endodontic microsurgery produced more microcracks on the resected root dentine surface compared to the high-speed tungsten carbide bur used during freehand apicoectomy.
UNASSIGNED: This study was performed to analyze the root-end surface for dentinal microcracks using a scanning electron microscope (SEM) after resection with high-speed bur and trephine drill.
UNASSIGNED: Thirty extracted single-rooted maxillary premolar teeth were selected and randomly distributed into two groups (n = 15). Working length was established using a #15 K-type file. Canals were prepared with a rotary Ni-Ti system to size 30/0.06 using endomotor, irrigated with 3% sodium hypochlorite, dried with paper points, and obturated with gutta-percha cones using a single-cone technique. All samples were mounted on preformed molds and poured using a mixture of sawdust and gypsum. In Group A; tungsten carbide bur was used to perform a freehand apicoectomy. In Group B; a trephine drill was used with a three-dimensional guide to perform 3 mm of root resection. Apicoectomy was performed in both groups under a dental operating microscope. Resected root ends were inspected for microcracks using SEM. The Shapiro-Wilk and Mann-Whitney U-test were used for statistical analysis.
UNASSIGNED: Microcracks were observed in all samples in both study groups. Trephine drill produced more microcracks on the resected root surface compared to the use of high-speed tungsten carbide bur with a statistically significant difference (P < 0.05).
UNASSIGNED: The trephine drill used during targeted endodontic microsurgery produced more microcracks on the resected root dentine surface compared to the high-speed tungsten carbide bur used during freehand apicoectomy.
摘要：
■根尖切除过程中形成的牙本质微裂纹可能导致牙根断裂和根尖准备密封不当的敏感性增加，这可能会对牙髓显微手术的结果产生负面影响。
■这项研究是在用高速钻头和环钻进行切除后，使用扫描电子显微镜（SEM）分析牙本质微裂纹的根端表面。
■选择30颗拔除的单根上颌前磨牙，随机分为两组（n=15）。使用#15K型文件建立工作长度。使用旋转Ni-Ti系统制备管道，尺寸为30/0.06，用3%次氯酸钠灌溉，用纸点干燥，并使用单锥技术用古塔胶锥封闭。将所有样品安装在预制模具上并用锯屑和石膏的混合物倾倒。在A组中；使用碳化钨钻头进行徒手根尖切除术。在B组中；使用环钻钻和三维导向器进行3mm的根部切除。两组均在牙科手术显微镜下进行根尖切除术。使用SEM检查切除的根端是否有微裂纹。使用Shapiro-Wilk和Mann-WhitneyU检验进行统计分析。
■在两个研究组的所有样品中均观察到微裂纹。与使用高速碳化钨钻头相比，在切除的根面产生了更多的微裂纹，差异有统计学意义（P<0.05）。
■与徒手根尖切除术中使用的高速碳化钨钻头相比，靶向牙髓显微手术中使用的环钻在切除的牙根牙本质表面产生了更多的微裂纹。
■这项研究是在用高速钻头和环钻进行切除后，使用扫描电子显微镜（SEM）分析牙本质微裂纹的根端表面。
■选择30颗拔除的单根上颌前磨牙，随机分为两组（n=15）。使用#15K型文件建立工作长度。使用旋转Ni-Ti系统制备管道，尺寸为30/0.06，用3%次氯酸钠灌溉，用纸点干燥，并使用单锥技术用古塔胶锥封闭。将所有样品安装在预制模具上并用锯屑和石膏的混合物倾倒。在A组中；使用碳化钨钻头进行徒手根尖切除术。在B组中；使用环钻钻和三维导向器进行3mm的根部切除。两组均在牙科手术显微镜下进行根尖切除术。使用SEM检查切除的根端是否有微裂纹。使用Shapiro-Wilk和Mann-WhitneyU检验进行统计分析。
■在两个研究组的所有样品中均观察到微裂纹。与使用高速碳化钨钻头相比，在切除的根面产生了更多的微裂纹，差异有统计学意义（P<0.05）。
■与徒手根尖切除术中使用的高速碳化钨钻头相比，靶向牙髓显微手术中使用的环钻在切除的牙根牙本质表面产生了更多的微裂纹。
