聚合度对核桩冠桩核联合体固位力的影响(英文)  

Influence of convergence angle on the retention of cast metal post and core restorations

作　　者：周笿 陈新民[1] 马砚南[1] 杨艳[1] 

机构地区：[1]四川大学华西口腔医学院修复科,四川省成都市610041

出　　处：《中国临床康复》2006年第37期175-179,共5页Chinese Journal of Clinical Rehabilitation

基　　金：四川省科技厅资助项目(02SY029-117)~~

摘　　要：背景:临床上通常采用桩核加金瓷冠的方式修复前牙残根,因牙冠的缺失,修复体的固位力主要由根桩提供,因此根桩所提供的固位力大小直接影响到远期修复效果。目的:分析不同聚合度铸造金属桩的固位力的变化,探讨桩聚合度对固位力的影响。设计:重复观察测量。单位:四川大学华西口腔医学院修复科。材料:实验于2005-05在四川大学高分子材料楼完成。制备标准尺寸的有机玻璃,模拟上中切牙牙根试件54个,分为桩道聚合度0°,3.93°,5.71°,7.48°,11.31°,14.71°组,9个/组。方法:①试件的制备:用数控精密机床分别进行聚合度为0°,3.93°,5.71°,7.48°,11.31°,14.71°的桩道预备。②黏接桩核的铸造:按临床操作制作桩核,确保试件与桩密合。在铸造金属核上磨一小洞,作为拉伸时拉钩穿过的位置。试件桩道、根面、铸造桩核用乙醇处理后吹干,磷酸锌水门汀黏固,黏固时加压直至黏接剂凝固。③桩固位力实验:将试件用生理盐水浸泡24h后进行拉伸加载测试,加载速度10mm/min,铸造桩核被拉出时的载荷即为桩核的固位力。④平面黏接力测试:制备有机玻璃圆柱,圆柱侧面上制备与中心长轴成0°,1.9°,3°,6°,9°,12°,15°斜面,制备矩形铜片。再铸造8个直径为8mm、厚1mm的小圆片。按临床操作情况将圆柱斜面、铜片喷沙面、铸造圆片清洁吹干后磷酸锌水门汀黏固,浸泡于生理盐水中24h后进行拉伸加载测试,加载速度10mm/min,铜片或铸造圆片从圆柱上脱落时的载荷即为不同聚合度的黏接力。⑤摩擦力和约束力的计算:桩可近似看作圆台,轴面黏接面积按圆台侧面积公式计算,桩与牙根的牙合面黏接面积为牙根面面积与桩道底面积之和。固位力、摩阻力、单位面积黏接力、单位面积固位力、单位面积摩阻力对聚合度之间进行回归分析。主要观察指标:①不同聚合度的黏接力测定。②不同聚合度�BACKGROUND： The residual root of anterior teeth are usually repaired by means of post and cores plus porcelain fused metal crown in clinic, and the retention force is mainly provided by the post because of the deletion of crown, so the retention force provided by the post is directly correlated with the long-term effect of repair. OBJECTIVE： To analyze the changes of retention of cast metal post and core restorations with different convergence angles, and investigate the influence of convergence angles on retention. DESIGN： A repeated observational measurement. SETTING： Department of Prosthodonties, West China School of Stomatology, Sichuan University. MATERIALS： The experiments were carried out in the building of high polymer material of Sichuan University in May 2005. Fifty-four simulated tooth roots were manufactured by the numerical control machine tools. They were divided into six groups according to the convergence angles of post being 0°, 3.93°, 5.71°, 7.48°, 11.31° and 14.71°, with nine specimens in each group. METHODS： ①Manufacture of the standard specimens： The tooth roots with the convergence angles of 0°, 3.93°, 5.71°, 7.48°, 11.31° and 14.71° were prepared with the digital control precision machine. ② Manufacture of the cast post and cores： The post and core wax patterns of the specimens were made in the condition similar to the clinical practice. The post and cores were cast and tried in, necessary grinding was made to ensure the adoption of the posts and the specimens. Then the posts were luted to the specimens with ZPC after the posts and the simulated root canals having been cleaned by alcohol. The posts and the specimens were pressed until the ZPC solidified.③ Retention Force test： After having been dipped in physiological saline for 24 hours, the bonded castings and specimens were subjected to a tensile testing at the drawing speed of 10 mm per minute. The retention force of post was the load recorded when the post was pulled out from the specimen.④

关 键 词：桩核技术 义齿固位 牙粘合 切牙 

分 类 号：R318[医药卫生—生物医学工程]