套筒冠及杆卡附着体对种植覆盖义齿应力分布的影响比较

A three-demension finite elements analysis of the combined bar-attachment and telescope-crown attachment in mandibular implant-retained overdenture

目的比较下颌颏孔前区套筒冠、杆卡附着体及二者联合式附着体对种植覆盖义齿应力分布影响。方法用CT扫描机,建模及分析软件CATIA,ABAQUS,建立健康无牙下颌骨模型;比较套筒冠、杆卡及二者联合式附着体三种模型对下颌种植覆盖义齿受到垂直载荷情况的受力情况。结果三种模型中,骨组织界面应力无明显差别,应力峰值出现在远中种植体的远中侧;杆卡式附着体模型中牙槽嵴表面上的最大压应力峰值为5.2Mpa,套筒冠式附着体模型的压应力峰值为5.0Mpa。结论下颌颏孔前区二者联合式及套筒冠附着体对于种植覆盖义齿应力分布影响优于杆卡式附着体。

Objective To compare the stress distribution of mandibular implant-surpported overdenture retained by bar-attachments and telescope crowns respectively by 3D-FEA. Methods 3D-FEA models of mandibular implant-supported overdenture retained by ball attachments and telescope crowns were constructed from a man＇ s mandible and a centric occlusal force was simulated to load on them. Results The stress in the bone interface was concentrated in the bone tissues around the neck of implant in both models. The maximum compressive stress in the surface of alveolar crest was 5.0 Mpa in the ball attachment model and 5.2 Mpa in the telescope crown model. The peak stress of central implant and lateral implant in the telescope crown model was lower than that of ball attachment model. Conclusion There is no statistic differences between the two type of attachment in the front of the foramina mentale of the mandible.