Department of Medical Biotechnologies, Unit of Endodontics and Restorative Dentistry, University of Siena, Siena, Italy.
Department of Medical Biotechnologies, Undergraduate Program in Dentistry, University of Siena, Siena, Italy, Phone: +39 0577 585772, e-mail:
J Contemp Dent Pract. 2020 Dec 1;21(12):1374-1378.
The present study compared the fracture strength and failure pattern of endodontically treated, bi-rooted, maxillary premolars with different number of coronal walls and postendodontic restoration (one vs double post).
105 premolars were divided into 3 groups according to the number of residual walls: control group (intact teeth; = 15), group 1 (3 residual walls; = 45), group 2 (2 residual walls; = 45). Each test group was then divided into 3 subgroups ( = 15 each) according to postendodontic restoration: no post (A), 1 post (B) or 2 posts (C). A load was applied parallel to the longitudinal axis of the teeth, thus simulating physiological occlusion. ANOVA and Tukey's tests were used to detect fracture strength differences among groups, while Chi-square test was used to check differences in fracture pattern.
No significant differences were observed between control group (intact teeth) and groups A1 ( = 0.999), B1 ( = 0.997) and C1 ( = 1.000); statistically significant differences were detected between control group and groups A2 ( < 0.001), B2 ( < 0.001) and C2 ( < 0.05). Different post placement techniques were non-significantly associated with fracture pattern in both groups 1 ( = 0.666) and 2 ( = 0.143) while, irrespective of the number of posts, the presence of the post was significantly associated with the fracture pattern in teeth with two residual walls. The double-post technique did not further improve the fracture resistance of hardly damaged endodontically treated maxillary bi-rooted premolars compared to single-post technique. Therefore, the insertion of a single post in the palatal canal could be a safer and more conservative choice.
The double-post technique did not further improve the fracture resistance of severely structurally compromised endodontically treated maxillary premolars with two roots compared to the single-post technique. Therefore, the safer and less invasive treatment is the placement of a single post in the palatal canal.
本研究比较了不同数量的冠壁和根管治疗后修复（单根 vs 双根）对双根管上颌前磨牙的骨折强度和破坏模式。
根据剩余壁的数量，将 105 个前磨牙分为 3 组：对照组（完整牙齿；n=15）、组 1（3 个剩余壁；n=45）和组 2（2 个剩余壁；n=45）。每个实验组根据根管治疗后修复情况再分为 3 个亚组（n=15）：无桩（A）、1 根桩（B）或 2 根桩（C）。载荷沿牙齿的纵轴平行施加，模拟生理咬合。采用方差分析和 Tukey 检验检测各组之间的骨折强度差异，采用卡方检验检测骨折模式差异。
对照组（完整牙齿）与 A1 组（n=0.999）、B1 组（n=0.997）和 C1 组（n=1.000）之间无显著性差异；对照组与 A2 组（n=0.001）、B2 组（n=0.001）和 C2 组（n=0.05）之间有显著性差异。在组 1（n=0.666）和组 2（n=0.143）中，不同的桩放置技术与骨折模式无显著相关性，而无论桩的数量如何，在有两个剩余壁的牙齿中，桩的存在与骨折模式显著相关。与单桩技术相比，双桩技术并不能进一步提高严重结构受损的双根管上颌前磨牙的抗折能力。因此，在腭侧管中植入单根桩可能是一种更安全、更保守的选择。
与单桩技术相比，双桩技术并不能进一步提高严重结构受损的双根管上颌前磨牙的抗折能力。因此，更安全、侵入性更小的治疗方法是在腭侧管中植入单根桩。
