不同固位形式可摘局部义齿对支持组织应力分布的研究

Study of the stress distribution on the supporting tissues of removable partial dentures with different retainer

目的:探讨附着体义齿与常见可摘局部义齿修复单侧游离端缺失对支持组织应力分布的影响。方法:分别以磁性附着体、RPI卡环组、联合卡环组三种固位形式的可摘局部义齿修复下颌单侧游离端缺失,用三维光弹应力冻结切片技术测试义齿加载后对基牙和缺牙区牙槽骨应力分布,并与基牙不戴义齿时载荷下的应力比较。结果:磁性附着体对54|基牙和缺牙区的牙槽骨应力稍大于RPI,只占54|基牙应力的48%,且对基牙近、远中应力基本相等;联合卡环对基牙牙槽骨应力最小,对缺牙区牙槽骨应力最大。结论:磁性附着体义齿修复单侧游离端缺失能够达到RPI义齿功能效果,特别适合于对美观和舒适要求较高者,不主张使用仅靠单侧固位的联合卡环组义齿。

Objective： To study the stress distribution on the supporting tissues of attachment dentures and common removable partial dentures （RPDs） of unilateral distal-extension edentulous. Method： Mandible unilateral distal-extension edentulous were restored with RPDs in magnetic attachment, RPI clasps and unilateral combined clasps. Three-dimensional photo-elastic frozen section method was used to test the stress distribution on abutment and edentudous alveolar. The stress of three forms of dentures are compared the abutment with no dentures. Result： The stress of magnetic attachment is little more than RPI denture on alveolar of abutments and edentulous. Magnetic attachment only occupy 48% of the stress on two abutments. And it is equal to the stress on abutments alveolar in mesial direction and distal direction on the whole. Thestress of combined clasps RPDs on the abutment alveolar is the smallest, while on the edentulous alveolar is the biggest. Conclusion： Magnetic attachment dentures used to restore unilateral distal-extension edentulous could attain to the function of RPI denture. And it is especially suitable for the patients who have high demands for sense of beauty and comfort. While the combined clasps RPDs is not recommended for unilateral distal-extension edentulous.