具有内部形连接和微线程的植入系统的旋转负荷疲劳性能
The International journal of oral & maxillofacial implants
|February 28, 2024
概括
牙植入物几何和直径并没有显著影响疲劳性能. 只有在正规直径的植入物中发生了故障,这给检索带来了挑战.
科学领域:
- 生物材料科学 生物材料科学
- 机械工程 机械工程
- 牙科植入物学 牙科植入物学
背景情况:
- 牙植入物设计,特别是带有微线程的内部形连接,对于机械稳定性至关重要.
- 了解植入物几何和直径对疲劳性能的影响,对于临床成功至关重要.
研究的目的:
- 评估植入物几何形状 (直线与形) 和直径 (4.2毫米与4.8毫米) 对Astra Tech EV植入物的旋转负载疲劳阻力的影响.
- 在周期性负载条件下识别潜在的故障模式.
主要方法:
- 四组Astra Tech EV植入物 (4.2毫米直线/圆形,4.8毫米直线/圆形) 与支柱进行了旋转负载疲劳测试.
- 在14Hz时,应用了35Ncm的曲矩,直到故障或5x10^6周期.
- 失败的样本使用扫描电子显微镜进行分析.
主要成果:
- 在正规直径 (4.2毫米) 组中发生了两次故障,涉及支柱螺丝和植入物骨折.
- 所有直径大 (4.8毫米) 的植入物都超过了疲劳极限,尽管有一个经历了支柱螺丝松动.
- 在植入物几何形状或直径之间没有发现疲劳性能的统计学上显著差异.
结论:
- 虽然没有发现显著差异,但故障仅限于直径为正规的植入物.
- 骨折位置 (植入物深处和模拟骨层以下) 存在潜在的检索困难.
- 植入物直径可能是抗疲劳的关键因素,需要进一步调查.
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