可靠性,故障模式和应力分布在形连接中,具有不同类型的保留方式
Michele Costa de Oliveira Ribeiro1, Vanessa Felipe Vargas-Moreno1, Rafael Soares Gomes2
1PhD student, Department of Prosthodontics and Periodontology, Piracicaba Dental School (FOP), University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
The Journal of prosthetic dentistry
|February 13, 2025
概括
渐变干扰适合 (TIF) 植入系统在无螺丝牙假体中表现出高可靠性. 然而,定制的角度支柱可能会降低TIF系统的可靠性,有利于传统的螺丝式系统.
科学领域:
- 生物材料和生物力学
- 牙科植入物学 牙科植入物学
- 牙修复 牙修复 牙修复 牙修复 牙修复
背景情况:
- 螺丝松动是牙科植入物假体的常见并发症.
- 无螺丝的形干扰适配 (TIF) 系统是为了解决这个问题而开发的.
- 对于TIF系统的生物力学数据有限,特别是对有角度支柱的系统.
研究的目的:
- 为了比较TIF系统的可靠性,故障模式和应力分布与传统的缩集成螺丝式 (TIS) 系统.
- 评估直线与定制的办公室角度支柱对TIF和TIS系统的影响.
- 在模拟的临床负载条件下评估生物机械性能.
主要方法:
- 105个单冠植入物被分为TIF和TIS组,具有直或角的支柱.
- 使用步骤应力加速寿命测试 (SSALT) 测试可靠性.
- 通过断层学分析了故障模式,并使用有限元分析 (FEA) 评估了应力分布.
主要成果:
- 在100N时,TIF系统的可靠性很高,而TIS-P的可靠性较低.
- 在150N时,TIS,TIS-P和TIF-A的可靠性下降,而TIF和TIS-A仍然很高.
- 在TIF系统中,FEA表明支柱应力增加,但植入应力减少,骨应力分布更好.
- 发生在跨粘膜支柱区域的故障.
结论:
- 由于高可靠性和有利的骨压力分布,TIF系统对于前部植入物支持的假肢是可靠的.
- 在办公室定制的支柱角度可能会损害TIF系统的可靠性.
- 当需要角度支柱时,传统的TIS系统可能更好.
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