Kabtoleh Alaa, Aljabban Ossama, Alsayed Tolibah Yasser
Endodontics, Damascus University, Damascus, SYR.
Pediatric Dentistry, Damascus University, Damascus, SYR.
Cureus. 2023 Jan 31;15(1):e34462. doi: 10.7759/cureus.34462. eCollection 2023 Jan.
Background and aims A root perforation is a connection between the root canal system and the external supportive tissues. Strip perforation (SP), occurring within root canals in a strip, can worsen the prognosis of a treated tooth, reduce its mechanical resistance, and impair the tooth structure. One of the suggested methods to treat SP is to seal it with a bio-material such as calcium silicate cement. Therefore, this in vitro study aimed to assess the molar structure impairment due to SP, which requires studying the fracture resistance, and the ability of mineral trioxide aggregate (MTA), bioceramic, and calcium-enriched mixture (CEM) to repair this perforation. Materials and methods Seventy-five molars were instrumented to size #25 and taper 4%, irrigated with sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA), dried, and then divided randomly into five groups (G1-G5): in G1, root canals were filled with gutta-percha and sealer (negative control sample), whereas the rest of the groups (G2-G5) had a manual simulated SP made with Gates Glidden drill at the mesial root of the extracted molar, and filled with gutta-percha and sealer up to their perforation area; in G2, SP was filled with gutta-percha and sealer (positive control sample); G3 used MTA to repair the SP; G4 used bioceramic putty; and G5 used CEM. Fracture resistance tests of the molars were conducted in the crown-apical direction using a universal testing machine. One-way ANOVA test and Bonferroni test were used to study the significance of the differences in the mean values of the tooth fracture resistance, where statistical significance was set at 0.05. Results The ANOVA test showed that there were statistically significant differences between the fracture resistance (in newtons) values among groups (p = 0.000). The Bonferroni test showed that G2 had a smaller fracture resistance mean than the other four study groups (656.53 N; p = 0.000), and that of G5 was smaller than G1, G3, and G4 (794.40 N, 1083.73 N, 1025.20 N, and 1034.20 N, respectively; p = 0.000 in each pairwise comparison). Conclusion SP reduced the fracture resistance of endodontically treated molars. SP restored using MTA and bioceramic putty was better than that treated with CEM and similar to molars without SP. Moreover, MTA and bioceramic putty enhanced the fracture resistance of endodontically treated teeth to levels similar to molars without SP.
背景与目的 牙根穿孔是根管系统与外部支持组织之间的连通。条状穿孔（SP）发生在根管内呈条状，会使治疗后牙齿的预后变差，降低其机械抗力，并损害牙齿结构。一种建议的治疗SP的方法是用生物材料如硅酸钙水门汀进行封闭。因此，本体外研究旨在评估由于SP导致的磨牙结构损害，这需要研究抗折性，以及三氧化矿物凝聚体（MTA）、生物陶瓷和富钙混合物（CEM）修复这种穿孔的能力。
材料与方法 75颗磨牙预备至25号锉、锥度4%，用次氯酸钠和乙二胺四乙酸（EDTA）冲洗、干燥，然后随机分为五组（G1 - G5）：G1组根管用牙胶和封闭剂充填（阴性对照样本），而其余组（G2 - G5）在拔除磨牙的近中根用盖茨 - 格利登钻制作人工模拟SP，并用牙胶和封闭剂充填至穿孔区域；G2组SP用牙胶和封闭剂充填（阳性对照样本）；G3组用MTA修复SP；G4组用生物陶瓷糊剂；G5组用CEM。使用万能试验机在牙冠 - 根尖方向对磨牙进行抗折性测试。采用单因素方差分析和邦费罗尼检验研究牙齿抗折性平均值差异的显著性，设定统计学显著性水平为0.05。
结果 方差分析显示各组之间抗折性（以牛顿计）值存在统计学显著差异（p = 0.000）。邦费罗尼检验显示G2组的抗折性平均值低于其他四个研究组（656.53 N；p = 0.000），G5组低于G1、G3和G4组（分别为794.40 N、1083.73 N、1025.20 N和1034.20 N；每组两两比较p = 0.000）。
结论 SP降低了根管治疗后磨牙的抗折性。用MTA和生物陶瓷糊剂修复SP的效果优于用CEM治疗的效果，且与无SP的磨牙相似。此外，MTA和生物陶瓷糊剂将根管治疗后牙齿的抗折性提高到与无SP磨牙相似的水平。
