摘要
目的:研究残冠牙体余量对核桩冠桩根联合体水平承载力学性能的影响。方法:制备标准尺寸的有机玻璃模拟上中切牙根144个,分成3种不同牙嵴高度和6种不同牙体余量共18组试件制作桩核蜡型、铸造、粘固。进行压缩测试,记录最大载荷。结果:牙体余量0mm、0.5mm、1mm、1.5mm、2mm、2.5mm组抗折力均数分别为232.90±25.93、246.68±50.43、259.21±66.33、269.23±69.35、272.25±43.44、279.08±62.91N,随牙体余量增加核桩冠桩根联合体水平承载力呈明显增长趋势。牙体余量0mm组与2mm、2.5mm组间差异具有统计学意义。牙体余量、桩冠根部总长和水平承载力之间成直线回归关系。结论:增加桩的长度可提高核桩冠桩根联合体的水平承载力,桩的长度即可向根部延长也可向冠部延长,牙体余量的增加延长了桩的长度从而提高了核桩冠桩根联合体水平承载力学性能。因此,在临床操作中应该尽量保留牙体组织,提高桩的长度增强核桩冠桩根联合体水平承载力学性能。
Objective： To evaluate the effects of the amount of residual tooth on the resistance ability to horizontal load in post and core crown and root system. Methods： 144 upper central incisor root analogs made of polymethylmethacrylate were divided into 18 groups according to 3 different heights of the alveolar ridge and 6 different amount of residual tooth. The posts and cores were cast and cemented on the roots. Then the samples were compressively loaded to fracture on Instron 4302 and the mode of failure was recorded. Results： The mean fracture resistance values were 232.90±25.93, 246.68±50.43,259.21±66.33, 269.23±69.35, 272.25±43.44 and 279.08±62.91 in groups with the amount of residual tooth for 0.5mm, 1.0mm, 1.5mm, 2.0mm and 2.5mm in turn. The fracture resistance increased with the increase of the amount of residual tooth. The fracture resistance in 2.0mm and 2.5mm groups was significantly greater than that in 0mm group. Linear regression analysis demonstrated significant association between the length of post, the amount of residual tooth and the fracture resistance. Conclusions： The fracture resistance increased with the increase of either the amount of residual tooth or the length of post. In clinical practice, the residual tooth should be preserved as much as possible.
出处
《口腔颌面修复学杂志》
2005年第4期268-270,274,共4页
Chinese Journal of Prosthodontics
关键词
残冠
桩根联合体
牙体余量
水平承载力
residual crown
post-core crown and root system
tooth remain
horizontal load
