Sharath Chandra S M, Agrawal Nishtha, Sujatha I, Sivaji K
Department of Conservative Dentistry and Endodontics, Krishnadevaraya College of Dental Sciences, Bengaluru, Karnataka, India.
J Conserv Dent. 2016 May-Jun;19(3):270-3. doi: 10.4103/0972-0707.181946.
The aim of this study is to compare in vitro the fracture resistance of the endodontically treated tooth restored with a novel design Sharonlay, with the two component restorative method, i.e., post with separate onlay, and onlay without post.
45 single-rooted mandibular second premolars were taken, and root canal treatment was performed. Teeth were then randomly divided into three groups (n = 15) based on the type of restoration given: Group I - metal onlay with cast post extension (Sharonlay), Group II - metal onlay with prefabricated metal post (Mani post system), Group III - metal onlay over endodontically treated tooth obturated with Gutta-percha (control group). Fracture resistance was checked using the Instron universal testing machine and the fracture patterns were analyzed.
According to the values recorded, Group I showed maximum mean fracture resistance followed by Groups II and III. Statistically significant difference was found between Groups I and II and Groups I and III and statistically significant difference was found between Groups II and III.
A single unit component Sharonlay, gives higher fracture resistance to a premolar as compared to (a) metal onlay with prefabricated metal post and (b) metal onlay over endodontically treated tooth.
本研究旨在体外比较采用新型设计Sharonlay修复的根管治疗牙与两种成分修复方法（即带单独高嵌体的桩和无桩高嵌体）的抗折性。
选取45颗单根下颌第二前磨牙，进行根管治疗。然后根据修复类型将牙齿随机分为三组（n = 15）：第一组——带铸造桩延长体的金属高嵌体（Sharonlay），第二组——带预成金属桩的金属高嵌体（马尼桩系统），第三组——用牙胶尖充填根管治疗后的牙齿上的金属高嵌体（对照组）。使用英斯特朗万能试验机检查抗折性并分析折裂模式。
根据记录的值，第一组显示出最大平均抗折性，其次是第二组和第三组。在第一组和第二组之间以及第一组和第三组之间发现有统计学显著差异，在第二组和第三组之间也发现有统计学显著差异。
与（a）带预成金属桩的金属高嵌体和（b）根管治疗后牙齿上的金属高嵌体相比，单一组分的Sharonlay能为前磨牙提供更高的抗折性。
