三种不同材料基台单牙全瓷修复体的抗折性比较

Comparison of Fracture Resistance of Single-tooth Implant-supported All-ceramic Restorations with Three Different Abutments

[目的]探讨三种不同材料基台单牙全瓷修复体在模拟口腔环境下的抗折强度.[方法]将45枚上颌中切牙氧化铝全瓷冠随机分为钛基台组（A组）、氧化铝瓷基台组（B组）和氧化锆瓷基台组（C组）三组,每组15枚.45枚氧化铝全瓷冠分别与三种材料的基台通过树脂粘合剂粘接形成修复体,固定于万能测试机上行体外加载直至修复体发生折裂,记录修复体破坏时的瞬间力值及折裂类型.采用秩和检验分析此3种修复体的抗折性差异（α=0.05）.[结果]45枚修复体均能耐受人工老化过程,且无螺钉脱落.三种不同材料修复体抗折强度分别为：A组1320.0N, B组418.6 N,C组 421.9 N,A组与B组和C组间比较具有显著性差异（P〈0.01）,而B组和C组间无明显差异（P〉0.05）.三组样本的全瓷冠折裂模式相似,均是全瓷冠的顶部及镶贴面材料的整体折裂.[结论]三种材料的修复体均能承受一定程度的牙 合力,适用于前牙区修复;A组较B组和C组的抗折性能好,可为相关人群的需要提供理论依据.

[Objective] To explore the fracture resistance of single-tooth implant-supported all-ceramic res torations with three different abutments under simulated oral condition. [Methods] Forty-five maxillary central incisor alumina crowns were randomly divided into titanium abutment group（group A）, alumina abutment group（group B） and zireonia abutment group（group C） with 15 in each., All 45 alumina crowns stuck to three abutments by using resin adhesive material and then formed restorations. The restorations were fixed on uni- versal testing machine and loaded in vitro until fracture. The moment load and type of fracture while the restorations were destroyed were recorded. Rank sum test was used to analyze the differences in fracture resistance among three abutments（a=0.05）. [Results] All 45 restorations could tolerate the artificial aging process and no screw loosed. The median fracture resistance of three abutments was 1320.0N（group A）, 418. 6N（group 13） and 421.9N（group C）, respectively. There were significant differences between group A and group I3 and C（ P 〈0. 001）. The difference between group B and group C was not significant（ P 〉0.05）. The fracture mode of the crowns in all groups was similar. All fractures were the total destruction at the top of the crown and veneering material. [Conclusion] The restorations with three abutments can endure the occlusal force at some extent, and can be used to repair the anterior teeth region. The fracture resistance in group A is better than that in group B and C. The result can provide the theoretical evidence for the demand of related population.