摘要
目的研究不同高度的箍结构设计对预成纤维桩核修复后牙体抗力的影响。方法32颗完整离体下颌第一前磨牙于颊侧釉牙骨质界上1mm处截冠,预备残根模型;按箍结构高度不同(0.0mm、1.0mm、2.0mm、3.0mm)分为4组,预成碳纤维桩联合复合树脂核修复残根。试件自铸造全冠颈缘完成线下2mm包埋于自凝塑料内,电子万能试验机以与牙长轴成150°、横梁位移速度1.0mm/min于颊尖顶加载,测定断裂载荷并进行统计学分析(α=0.05)。结果箍结构高度为1.0mm组与箍结构高度为2.0mm和3.0mm组相比,均表现出较高的折裂载荷(P<0.05)。结论采用牙冠延长术设计高度2.0mm以上的箍结构,会降低桩核冠修复后牙体的抗力。
Objective To investigate the effect of various ferrule lengths on the fracture resistance of endodontically treated teeth restored with prefabricated carbon fiber post-and-core system. Methods Thirty-two extracted endedonticaUy treated mandibular first premolars were sectioned perpendicular to the long axis at a point 1.0 mm occlusal to the buccal cementoenamel junction （CEJ）. All the prepared endodontically treated root models were divided into four groups according to the ferrule lengths from 0.0 mm to 3.0 mm with 1.0 mm interval each （Group A, B, C and D）. After restoration with prefabricated carbon fiber post-and-core system, each specimen was embedded in a self-cured acrylic resin block from 2.0 mm apical to the margins of a cast Ni-Cr alloy crown,then loaded at 150 degrees from the long axis in a universal testing machine at the crosshead speed of 1.0 mm/min until fracture. Data were recorded and analyzed using ANOVA and Fisher＇ s exact tests, with a = 0.05. Results Compared with Group C and Group D, Group B demonstrated significantly higher fracture strengths （ P 〈 0. 05）. Conclusions Crown lengthening with a ferrule length more than 2.0 mm resulted in reduced fracture strengths for endodontically treated roots restored with prefabricated carbon fiber post-and-core system and cast metal crowns.
出处
《口腔医学》
CAS
2007年第3期146-148,共3页
Stomatology
关键词
箍结构
纤维桩
残根
抗力
femde
fiber post
endodontically treated root
fracture resistance
