在定制CAD/CAM和预制支柱和螺丝之间对逆扭矩值的比较分析:一个体外研究
The International journal of oral & maxillofacial implants
|September 24, 2024
概括
定制的CAD/CAM支柱显示了比预制支柱更低的移除扭矩值,这引发了人们对其在循环负荷下机械成功的担忧. 需要进一步的临床研究来比较它们的长期有效性.
科学领域:
- 牙科植入物学 牙科植入物学
- 生物材料科学是生物材料的科学.
- 机械工程 机械工程 机械工程
背景情况:
- 牙科植入物修复需要稳定的支柱和螺丝连接.
- 定制的计算机辅助设计/计算机辅助制造 (CAD/CAM) 支架提供患者特定的解决方案.
- 预制支柱提供了一个标准化的替代方案.
研究的目的:
- 为了比较定制CAD/CAM与预制支柱和螺丝的机械稳定性.
- 为了评估循环负荷对这些组件移除扭矩值 (RTV) 的影响.
- 在重复加载后评估螺丝疲劳性能.
主要方法:
- 28个牙科植入物被分为两组:预制和定制的CAD/CAM支柱/螺丝.
- 移除扭矩值 (RTVs) 在5万次和100万次加载周期之前和之后进行测量.
- 通过重新收紧和重新测量RTVs来评估螺丝疲劳.
- 统计分析包括ANOVA和配对t测试.
主要成果:
- 预制支柱最初显示的RTV明显高于定制CAD/CAM支柱.
- 这两组在循环加载后的RTV显著下降.
- 定制的CAD/CAM支柱显示了显著较低的RTV,特别是在100万个循环后.
- 两组之间没有观察到螺丝疲劳性能的显著差异.
结论:
- 与预制部件相比,定制的CAD/CAM支柱和螺丝具有较低的机械稳定性.
- 减少的RTV引发了关于定制CAD/CAM支柱的临床有效性和广泛应用的问题.
- 进一步的临床研究对于验证定制与预制植入物组件的长期机械成功至关重要.
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