不同牙髓延伸深度的CAD/CAM氧化锆内冠粘结于上颌磨牙的抗折性、失效模式及可修复性：一项体外研究

Fracture resistance, failure mode and restorability of CAD CAM Zirconia endocrowns with different pulpal extension depths bonded to maxillary molars: an in-vitro study.

作者信息

Gaafar Sarah Salah, El Ballouli Dana, Rayyan Mohammad, Sayed Mohamed, Basta Doaa Gamal, Fouad Maha

机构信息

Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, Dar Al Uloum University, Riyadh, Saudi Arabia.

Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.

出版信息

BMC Oral Health. 2025 Feb 1;25(1):176. doi: 10.1186/s12903-025-05466-9.

DOI:10.1186/s12903-025-05466-9

PMID:39893449

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11786583/

Abstract

BACKGROUND

Pulpal extension depth (PED) is critical for endocrowns restored teeth stability and longevity. There is a conflicting result regarding the minimum PED needed for the success of endocrowns. The aim of the current study was to compare Fracture resistance, failure mode, and restorability of CAD-CAM zirconia endocrowns with different pulpal extension depths bonded to maxillary molars.

MATERIALS AND METHODS

Forty maxillary 1st molars were selected, decoronated, and randomly divided into 4 main groups (n = 10) according to the PED measured from the pulpal floor to the occlusal end of the wall height into; group D2, PED was 2 mm, group D3, PED was 3 mm, group D4, PED was 4 mm, group D5 PED was 5 mm. Teeth were prepared and secured in resin dies with pseudo periodontal ligament. Specimens from all groups were individually scanned using an intra oral digital scanner. Monolithic zirconia endocrowns were constructed and bonded to their corresponding. Following thermal cycling, each specimen was axially loaded in a universal testing machine at a 0.5 mm/min crosshead speed. Failure modes were inspected, and restorability of specimens was recorded. Data was collected, tabulated, and statistically analyzed.

RESULTS

Descriptive statistics displayed higher mean value of the D2 group (3657 1673.8 N) followed by the D3 group (3009.3 853.5 N), then the D4 group (2087.3 413.9 N) and finally the D5 group (1972.7 ±330.4 N). At a 95% confidence level, one-way analysis of variance (ANOVA) revealed significant differences between tested groups. (P = 0.014). Regarding failure mode, D2 recorded 100% restorable failures, followed by D3 (90%) and D4 (60%), while the least was D5 (50%).

CONCLUSIONS

Endocrowns with 2 mm PED recorded the highest fracture resistance and the highest restorable failure modes. Endocrowns with 5 mm PED recorded the lowest fracture resistance and the lowest restorable failure modes. Tall walls should be shortened during the preparation of endocrowns in maxillary molars.

摘要

背景

牙髓延伸深度（PED）对于嵌体冠修复牙齿的稳定性和寿命至关重要。关于嵌体冠成功所需的最小牙髓延伸深度，存在相互矛盾的结果。本研究的目的是比较不同牙髓延伸深度的计算机辅助设计与制造（CAD-CAM）氧化锆嵌体冠粘结到上颌磨牙后的抗折性、失败模式和可修复性。

材料与方法

选取40颗上颌第一磨牙，去除牙冠，并根据从髓底到壁高咬合端测量的牙髓延伸深度随机分为4个主要组（n = 10）；D2组，牙髓延伸深度为2mm；D3组，牙髓延伸深度为3mm；D4组，牙髓延伸深度为4mm；D5组，牙髓延伸深度为5mm。制备牙齿并固定在带有假牙周韧带的树脂模型中。使用口腔内数字扫描仪对所有组的标本进行单独扫描。制作整体氧化锆嵌体冠并粘结到相应的牙齿上。经过热循环后，每个标本在万能试验机上以0.5mm/min的十字头速度进行轴向加载。检查失败模式，并记录标本的可修复性。收集数据、列表并进行统计分析。

结果

描述性统计显示，D2组的平均值较高（3657±1673.8N），其次是D3组（3009.3±853.5N），然后是D4组（2087.3±413.9N），最后是D5组（1972.7±330.4N）。在95%置信水平下，单因素方差分析（ANOVA）显示测试组之间存在显著差异（P = 0.014）。关于失败模式，D2组记录的可修复失败率为100%，其次是D3组（90%）和D4组（60%），而最低的是D5组（50%）。