下颌桩核基牙式全口覆盖义齿基牙牙周支持组织的应力分析

目的 :研究下颌桩核基牙式全口覆盖义齿基牙牙周支持组织的应力分布状况 ,为临床工作提供实验依据和指导。方法 :应用三维有限元应力分析法研究下颌尖牙桩核基牙式全口覆盖义齿基牙牙周支持组织的应力分布特点 ,计算基牙牙周膜、骨硬板的应力值并与自然基牙作对比分析。结果 :基牙远中受力较大。桩核的存在可降低基牙颈部远中及根尖区近中牙周膜的应力值 ,增大根中部远中、根下 1/2近中牙周膜的应力值。桩核可增大基牙颈部远中骨硬板的应力值但减小颈部以下骨硬板的应力值。结论 :基牙有向远中倾斜的趋势 ;桩核对基牙牙周膜及骨硬板的应力分布有一定影响 ;桩有减小根尖部应力的趋势。

Stress analysis of periodontal supporting tissues of mandibular complete overdenture based on post-core abutment

Objective:To study the stress distribution of periodontal supporting tissues of mandibular complete overdenture based on post-core abutment. Methods:3-D finite element method (FEM) was employed to investigate the stress distribution of periodontal supporting tissues of mandibular complete overdenture based on post-core abutment, the stress values of periodontal membrane and lamina dura were calculated and compared with those of natural abutment. Results:The values of stress in distal area of abutment were larger than that in medial area. Post-core reduced periodontal membrane stress value in distal area of abutment cervix dentin, as well as that in apical zone, increased the stress value in distal periodontal membrane of the middle part of root, raised the stress value of distal lamina dura of abutment cervix dentin, while reduced the stress value below the cervix dentin. Conclusion:Abutment tends to incline distally. Post-core can influence stress distribution of periodontal membrane and lamina dura and reduce the stress value on root-end.