中国实用口腔科杂志

中国实用口腔科杂志 ›› 2011, Vol. 4 ›› Issue (08): 485-487.

• 论著 • 上一篇    下一篇

钴铬合金及纯钛铸造卡环疲劳性能比较研究

  

  1. 大连市口腔医院·大连大学附属口腔医院修复科，辽宁  大连  116021
  • 收稿日期:2011-06-02 修回日期:2011-07-30 出版日期:2011-08-15 发布日期:2011-09-07

  • Received:2011-06-02 Revised:2011-07-30 Online:2011-08-15 Published:2011-09-07

摘要：

目的    比较钴铬合金和纯钛铸造卡环在不同倒凹深度下的疲劳寿命，为临床卡环材料的选择提供依据。方法    2009年10至2010年4月在大连市口腔医院采用两种钴铬合金Vitallium2000、Vera PDS和纯钛分别铸造直型卡环各10个。根据弯曲位移的不同每组再分成0.25 mm和0.5 mm两组，每组各5个试件。使用万能材料测试机在卡环尖端加载交变载荷，距卡环尖端5 mm卡环臂处发生弹性形变，加载方向是由卡环的平面侧向曲面侧弯曲。频率20 Hz。当载荷衰减为小于初始载荷的15%时认为卡环已经疲劳失效。初始载荷和疲劳失效时的载荷循环次数被自动记录。结果    （1）位移为0.25 mm时， 3种金属铸造卡环的初始载荷之间差异具有统计学意义 （P < 0.05），其中Vera PDS合金高于Vitallium2000，纯钛铸造卡环最小；在循环次数方面，纯钛卡环与 Vitallium2000卡环之间差异无统计学意义（P = 0.135），而Vera PDS卡环的循环次数显著高于其余两者（均P＜0.05）。（2）当弯曲位移为0.5 mm时，纯钛卡环的初始载荷明显小于Vitallium2000、Vera PDS卡环组（均P＜0.05），后两者之间差异无统计学意义 （P = 0.327）；在循环次数方面，纯钛卡环的循环次数低于后两者（均P＜0.05）， Vitallium2000、Vera PDS卡环组之间差异无统计学意义 （P = 0.103）。结论    Vera PDS钴铬合金铸造卡环的疲劳寿命高于Vitallium2000卡环和纯钛铸造卡环。

关键词: 铸造卡环, 疲劳寿命, 倒凹深度

Abstract:

Objectives    To compare the fatigue performance of three kinds of metal clasps in different undercut depth， providing theoretical evidence for choosing different material alloys in clinic. Methods    From 2009.10 to 2010.4， two kinds of co-cr alloy （Vitallium2000，Vera PDS） and pure titanium were used to cast ten straight clasps respectively according to the recommended investment system and corresponding casting method in Dalian Stomatological Hospital . Based on the difference of deflection displacement，each clasp group was divided into two groups：0.25 mm／0.5 mm，5 pieces in each group. The constant-deflection fatigue test was carried out with a pneumatic testing machine in this study. The alternating force was loaded on the clasp tip. Elastic deformation took place on the situation of 5㎜ from the tip of the clasp arm. The load direction was from the flat side to curve side， the frequency 20Hz.The test was terminated when the force was reduced to less than 15% of the initial load. The initial load and number of loading cycles were recorded automatically. Results    （1）When the displacement was 0.25 mm，there was statistic significant difference in three kinds of alloy clasps （P＜0.05）. The initial load of Vera PDS was more than Vitallium2000 and pure titanium， and pure titanium’s was the smallest. In the number of loading cycles， there was no significant difference between Vitallium2000 and pure titanium （P=0.135）. Vera PDS was significant more than the other two（P＜0.05）. （2）When the displacement was 0.5mm， the initial load of pure titanium was less than vitallium2000 and Vera PDS（P＜0.05 each），and there was no difference in the other two （P = 0.327）. In the number of loading cycles， pure titanium was less than Vitallium2000 and Vera PDS（P＜0.05 each）.There was no difference between Vitallium2000 and Vera PDS （P = 0.103）. Conclusion    The fatigue life of Vera PDS clasps is longer than that of Vitallium2000 clasps and pure titanium clasps.

Key words: casting clasps；fatigue life；undercut depth