不同框架材料对远距离延伸可拆卸部分假牙引起的应力的影响:张力计分析
Maha Mahmoud Fahmy1, Mahmoud Hassan Al-Afandy1, Hebatallah Tarek Mohamed1
1Oral and Maxillofacial Prosthodontics Department, Faculty of Dentistry, Ain-Shams University, Cairo, Egypt.
概括
聚基基 (PKK) 可拆卸部分假牙 (RPD) 与- (Co-Cr) RPD相比,将较少的应力转移到支架上,但更多的应力转移到残留脊上. PKK可能适用于具有损坏支柱的RPD.
科学领域:
- 生物材料科学 生物材料科学
- 牙科假肢 牙科假肢
- 生物力学 生物力学
背景情况:
- 可拆卸部分假牙 (RPD) 对于恢复部分无牙患者的功能和美学至关重要.
- 对于RPD框架的材料选择显著影响压力分布和支口腔结构的寿命.
- - (Co-Cr) 合金是传统的材料,而聚基基 (PEKK) 是一种具有潜在好处的较新的替代品.
研究的目的:
- 为了在远端延伸RPD中比较PEKK和Co-Cr材料之间传递到支柱和残余的应变.
- 评估这些材料在RPD功能期间保护支结构方面的潜力.
主要方法:
- 创建了一个肯尼迪I类部分无牙下弓的虚拟模型,并用于打印两组RPD框架 (每组n=5).
- 框架是由Co-Cr合金或PEKK空白制成的.
- 应力测量器罗塞特被连接到支柱和残余脊,并受到单边垂直和斜负荷. 统计分析包括曼-惠特尼U和弗里德曼测试 (p ≤0.05).
主要成果:
- 在垂直负载下,在负载和不负载的支柱上,以及在不负载的残余脊上,在PEKK和Co-Cr组之间观察到显著的应变差异.
- 在斜负荷下,在所有测量位置上,在两组材料之间发现了统计学上显著的拉伸差异.
结论:
- 与Co-Cr.相比,PEKK材料造成了对支柱的较低压力,但对残余的压力更高.
- PEKK可能是支持弱化支柱的RPD的推材料,可能有助于维护口腔结构.
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