【摘要】 我们旨在研究残冠牙体余量对核桩冠修复体核桩脱位力的影响。制备标准尺寸的有机玻璃模型,模拟牙根,制作核桩蜡型、铸造、黏固。进行拉伸测试,记录脱位瞬间的力值。另制作试件,测试出有机玻璃与铸造金属的平面黏结力。结果显示,牙体余量增加,核桩脱位力明显增大,特别是每增加1 mm,脱位力出现显著性差异。核桩冠根部总长及牙体余量与脱位力、黏结力及摩擦阻力成直线回归关系,并得出回归方程。因此,临床核桩修复牙体预备时应尽量保留牙体组织,这样会增强修复体的抗脱位能力。更多还原

【Abstract】 This study was amimed to assess the effects of remain of residual tooth on the retention of postcore crown system.Simulated roots made of polymethylmethacrylate were manufactured.Then the wax pattern of post-core was made,casted and cemented.The post-core was tested at the speed of 10mm/min on the Instron4302,and the retention force was recorded.Other samples were made and subjected to the test for cohesion of polymethylmethacrylate and metal.The result showed that retention significantly increased with the adding of the residual tooth.When the length of post was longer than 8 mm and 1 mm was added to tooth remain,the difference in retention between the two groups was statistically significant.It was noted that there existed relationships of retention to length of post and tooth remain,of cohesion to length of post and tooth remain,and of frictiion resistence to length of post and tooth remain;moreover,the relevant linear regression equations were obtained.So during the tooth preparation of post-core system,the tooth tissue should be reserved as much as possible.更多还原