附着体式全口覆盖义齿的基牙位移

目的探讨球形、磁性和杆式附着体对下颌全口覆盖义齿基牙位移的影响。方法制作球形、磁性和杆式附着体式覆盖义齿,在后牙区放置食物片并负载2 kgf、4 kgf、6 kgf、8 kgf时,用激光位移测量仪测量计算出基牙的位移量,进行统计分析。结果双侧后牙放置食物片时,磁性附着体垂直向位移最大,球形附着体的唇舌向倾斜和水平扭转最大,杆式附着体近远中位移最大。单侧后牙放置食物片时,工作侧除垂直向位移外,杆式附着体均大于磁性附着体。非工作侧杆式附着体在近远中和唇舌向倾斜、水平扭转均为最大;球形附着体在唇舌向倾斜和移动大于磁性附着体。结论不同附着体类型的覆盖义齿基牙,在实验中显示出不同的位移、倾斜、扭转的运动特点,磁性固位方式较杆式固位方式具有更好的生物力学效应。

Study on abutment displacement of overdentures with attachments

Objective To study the influence of three different types of attachments on abutment displacement of mandibular overdentures.Methods To fabricate study model(Nissin Co,Japan) overdentures with ball,magnet,and bar attachments.Food chips were placed on the occlusal surface and the dentures were loaded by 2 kgf,4 kgf,6 kgf,8 kgf respectively.The abutment displacements were measured by laser displacement sensor.All data were analyzed by statistic software.Results It was found that when food chips were masticated between bilateral sides of dentition,magnet-attachments gone greatest vertical displacement changes,ball-attachments showed greatest labial-lingual inclination and torsion changes of,and bar-attachments resulted in greatest mesialdistal displacement changes.When food chip was masticated between unilateral side of dentition,changes(inclination,torsion and displacement) of bar-abutments were bigger than magnet-abutments on the working side except for vertical displacement.Changes(inclination and torsion) of bar-abutments were the biggest on the non-working side.Changes(labial-lingual) of ball-abutments were bigger than magnet-abutments on the non-working side.Conclusion Overdentures with different attachments showed different characteristics in inclination,torsion,and displacement.Magnets were better than bars in stress distribution.