Pauletto Guilherme, de Pellegrin Sidnei Flores, Padoin Yasmin, Vargas Andressa Weber, Castillo Duvan Cala, Pereira Gabriel Kalil Rocha, Bier Carlos Alexandre Souza, Morgental Renata Dornelles
Faculty of Dentistry, Federal University of Santa Maria (UFSM), Roraima Avenue #1000, T Street, Building 26F, Room 2383, Santa Maria, Rio Grande do Sul State, 97.105-900, Brazil.
Odontology. 2025 Aug 29. doi: 10.1007/s10266-025-01185-3.
This study aimed to investigate the influence of apical root resection level and root canal filling technique on the fracture resistance of endodontically treated teeth. Eighty mandibular premolars were selected and evenly distributed based on similar anatomical characteristics into two groups (n = 40) according to the root canal filling technique: single-cone technique and lateral compaction technique. One week after root canal treatment, each group was further divided into four subgroups (n = 10) based on the level of apical root resection: without root resection, 3 mm, 4 mm, and 5 mm. Following resection, a retrograde cavity was prepared and filled with mineral trioxide aggregate. All specimens were embedded in cylindrical acrylic molds and subjected to a fracture resistance test and fracture pattern analysis. Two-way ANOVA, Tukey's post hoc and Fisher's exact tests were performed (α = 5%). Teeth that underwent apical root resection 5 mm from the apex demonstrated significantly lower fracture resistance compared to those without root resection (p < 0.05). No differences were observed among the 3 mm and 4 mm resection groups, nor between these groups and the groups without resection or with 5 mm resection (p > 0.05). The root canal filling technique did not affect fracture resistance (p > 0.05) and the fracture pattern was similar between groups (p > 0.05). In conclusion, the fracture resistance of endodontically treated teeth decreased following a 5 mm apical root resection. The single-cone and lateral compaction techniques demonstrated comparable biomechanical performance.
本研究旨在调查根尖切除术水平和根管充填技术对根管治疗后牙齿抗折性的影响。选取80颗下颌前磨牙，根据根管充填技术，基于相似的解剖特征将其均匀分为两组（n = 40）：单锥技术组和侧方加压技术组。根管治疗1周后，根据根尖切除术水平，每组再进一步分为四个亚组（n = 10）：未进行根尖切除术、根尖切除3 mm、4 mm和5 mm。切除后，制备倒充填洞形并用三氧化矿物凝聚体充填。所有标本嵌入圆柱形丙烯酸模具中，进行抗折性测试和折裂模式分析。采用双向方差分析、Tukey事后检验和Fisher确切概率法（α = 5%）。与未进行根尖切除术的牙齿相比，根尖切除5 mm的牙齿抗折性显著降低（p < 0.05）。3 mm和4 mm切除组之间以及这些组与未切除组或5 mm切除组之间均未观察到差异（p > 0.05）。根管充填技术不影响抗折性（p > 0.05），且各组之间的折裂模式相似（p > 0.05）。总之，根尖切除5 mm后，根管治疗后牙齿的抗折性降低。单锥技术和侧方加压技术表现出相当的生物力学性能。
