Department Surgical Sciences, Dental School, University of Turin, Turin, Italy.
Department of Surgical Sciences, Dental School, University of Turin, Turin, Italy.
Clin Oral Investig. 2021 Oct;25(10):5967-5975. doi: 10.1007/s00784-021-03902-y. Epub 2021 Apr 15.
To evaluate different direct restoration techniques on various cavity designs in anterior endodontically treated teeth (ETT).
Ninety upper central incisors (n = 90) were selected, endodontically treated, and divided into three groups (n = 30) accordingly to the cavity design: minimal endodontic cavity access (group A), endodontic access + mesial class III cavity (group B), and endodontic access + two class III cavities (group C). Three subgroups (n = 10) were then created accordingly to the restoration technique: nano hybrid composite restoration (subgroup a), glass fiber post + dual-cure luting cement (subgroup b), and bundled glass fiber + dual-cure luting cement (subgroup c). Samples underwent micro-CT scan, chewing simulation, and a second micro-CT scan. 3D quantification (mm) of interfacial gap progression was performed; then, samples underwent fracture resistance test. Data were statistically analyzed setting significance at p < 0.05.
Groups A and B showed significantly lower interfacial gap progression compared with group C. Subgroup b performed significantly better compared with subgroups a and c. Improved fracture strength was reported for group C compared with group A, while both subgroups b and c performed better than subgroup a.
Cavity design significantly influenced interfacial gap progression and fracture resistance. Fiber posts significantly lowered gap progression and improved fracture resistance while bundled fibers only increased fracture resistance. A significant reduction of non-repairable fractures was recorded when fibers were applied.
A minimally invasive approach, conserving marginal crests, should be applied whenever possible. Inserting a fiber post is indicated when restoring anterior ETT, in order to reduce gap progression, improve fracture resistance, and avoid catastrophic failures.
评估不同直接修复技术在前牙牙髓治疗牙（ETT）不同窝洞设计中的应用。
选择 90 颗上颌中切牙（n=90），进行根管治疗，然后根据窝洞设计分为三组（n=30）：最小根管入口窝洞（A 组）、根管入口+近中 III 类窝洞（B 组）和根管入口+两个 III 类窝洞（C 组）。然后，根据修复技术将每组分为三个亚组（n=10）：纳米混合复合材料修复（a 亚组）、玻璃纤维桩+双固化水门汀（b 亚组）和捆绑玻璃纤维+双固化水门汀（c 亚组）。对样本进行微 CT 扫描、咀嚼模拟和第二次微 CT 扫描。对界面间隙进展的 3D 定量（mm）进行了分析；然后，对样本进行了抗折强度测试。设置 p<0.05 为显著性水平，对数据进行了统计学分析。
与 C 组相比，A 组和 B 组的界面间隙进展明显较低。与 a 亚组和 c 亚组相比，b 亚组表现出更好的性能。与 A 组相比，C 组的骨折强度得到了改善，而 b 亚组和 c 亚组的性能均优于 a 亚组。
窝洞设计显著影响界面间隙进展和抗折强度。纤维桩显著降低了间隙进展并提高了抗折强度，而捆绑纤维仅提高了抗折强度。当使用纤维时，记录到非可修复性骨折显著减少。
只要可能，应采用微创方法，保存边缘嵴。在前牙牙髓治疗中，为了减少间隙进展、提高抗折强度和避免灾难性失败，应插入纤维桩。
