定制和现有形-形支柱的200万周期疲劳性能:移除扭矩和SEM研究
Furkan Selvi1, Berk Bilgen2, Meltem Özdemir Karataş2
1Istanbul University, Faculty of Dentistry, Institute of Health Sciences, Istanbul, Turkey.
Clinical implant dentistry and related research
|September 5, 2025
概括
定制支柱保持预负荷类似于牙科植入物中的原始支柱,尽管起始扭矩较低. 早期重新拉紧螺丝是稳定的关键.
科学领域:
- 生物材料科学
- 牙科植入物学
- 机械工程
背景情况:
- 螺丝松动是植入式假肢的常见机械并发症.
- 螺杆前负荷的损失是螺杆松动的主要原因.
- 评估支柱机械性能对于长期的植入成功至关重要.
研究的目的:
- 为了比较CAD-CAM定制支柱 (CA) 和原始支柱 (SA) 的机械性能.
- 在长期循环负荷下评估预负荷损耗和表面形态.
- 为了确定支柱螺丝固定的长期稳定性.
主要方法:
- 四十四个植入器支架组件 (内部形-六边形连接) 分为SA和CA组.
- 按照ISO-14801标准进行了高达2x10^6周期的循环加载.
- 在多个时间点分析了移除扭矩值 (RTV) 和表面形态 (SEM).
主要成果:
- 对于SA,基线RTV高于CA. 这两组的RTV均下降至1x10^6周期.
- 在1x10^6周期之前,CA的RTV显著降低;此后观察到部分RTV恢复.
- 在SA中,SEM显示出更多的磨损,而CA显示出局部的适应;所有样本都保持了线程完整性.
结论:
- 在200万个循环后,定制支柱保持了有效的预载荷,与库存支柱相美.
- 定制和原始支柱在机械上适用于功能性载荷.
- 最大的预负载损失发生在早期 (50,000-1x10^6周期),建议早期重新紧固支柱螺丝.
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