用全瓷修复体修复的根管治疗前磨牙的应变测量和抗折性

Strain measurements and fracture resistance of endodontically treated premolars restored with all-ceramic restorations.

作者信息

Seow Liang Lin, Toh Chooi Gait, Wilson Nairn H F

机构信息

School of Dentistry, International Medical University, 126, Jalan Jalil Perkasa 19, 57000 Kuala Lumpur, Malaysia.

出版信息

J Dent. 2015 Jan;43(1):126-32. doi: 10.1016/j.jdent.2014.10.001. Epub 2014 Oct 19.

DOI:10.1016/j.jdent.2014.10.001

PMID:25448436

Abstract

OBJECTIVES

The aim of this study was to investigate the recovery of cuspal stiffness and fracture resistance in endodontically treated maxillary premolars restored with bonded ceramic inlays and onlays of various designs.

METHODS

Seventy intact premolars were selected for this study; six cavity designs were investigated: (i) mesio-occlusal-distal (MOD) inlay (I), (ii) MOD inlay with palatal cusp coverage (IPC), (iii) MOD onlay (O), (iv) MOD inlay with pulp chamber extension (IPE), (v) MOD inlay with palatal cusp coverage and pulp chamber extension (IPCPE), and (vi) MOD onlay with pulp chamber extension (OPE). Intact teeth acted as control. Strain gauges were attached to the buccal and palatal surfaces of the teeth to measure cuspal stiffness under static loading. All specimens were eventually subjected to compressive load to failure. Cuspal stiffness and fracture resistance data were analyzed using ANOVA and Tukey test.

RESULTS

The I and IPE restorations restored cuspal stiffness to 75% of the sound tooth value. The O and OPE restored teeth had stiffness values greater than that of a sound tooth. The I, IPC, O, IPE, IPCPE and OPE restored teeth demonstrated fracture strength values of 938N±113 N (s.d.), 1073N±176 N and 1317N±219 N, 893N±129 N, 1062N±153 N and 1347N±191 N respectively.

CONCLUSIONS

Within the limitations of this study, it was concluded that the all-ceramic onlay or inlay with palatal cusp coverage provided best biomechanical advantage in restoring an endodontically treated maxillary premolar tooth.

CLINICAL SIGNIFICANCE

The onlay approach which is more conservative compared to full coverage restoration is considered an appropriate approach to the restoration of endodontically treated maxillary premolars. The addition of a pulpal extension to the all-ceramic restorations, apart from being technically challenging, was not found to offer any biomechanical advantage to the restored teeth.

摘要

目的

本研究旨在调查用各种设计的粘结陶瓷嵌体和高嵌体修复的根管治疗上颌前磨牙的牙尖刚度恢复情况和抗折性。

方法

本研究选取70颗完整的前磨牙；研究了六种洞型设计：（i）近中-咬合-远中（MOD）嵌体（I），（ii）覆盖腭尖的MOD嵌体（IPC），（iii）MOD高嵌体（O），（iv）延伸至髓腔的MOD嵌体（IPE），（v）覆盖腭尖并延伸至髓腔的MOD嵌体（IPCPE），以及（vi）延伸至髓腔的MOD高嵌体（OPE）。完整牙齿作为对照。在牙齿的颊面和腭面粘贴应变片，以测量静态加载下的牙尖刚度。所有标本最终承受压缩载荷直至破坏。使用方差分析和Tukey检验分析牙尖刚度和抗折性数据。

结果

I和IPE修复体将牙尖刚度恢复到健全牙齿值的75%。O和OPE修复的牙齿刚度值大于健全牙齿。I、IPC、O、IPE、IPCPE和OPE修复的牙齿的抗折强度值分别为938N±113N（标准差）、1073N±176N和1317N±219N、893N±129N、1062N±153N和1347N±191N。