不同固位力下杆式附着体的基牙位移

The Effect of Retention on Displacement,Inclination and Torsion of Abutment of Bar-Attachments

目的研究不同固位力对下颌杆式附着体式全口覆盖义齿基牙位移的影响。方法在上牙列完整,下颌仅余两颗尖牙的实验模型上,分别制作固位力为500 g、930 g、1 450 g的杆式附着体式覆盖义齿。在双侧后牙区放置食物片的咬合状态下,负载2 kg、4 kg、6 kg、8 kg咀嚼力时,测量并计算出基牙在近远中向、唇舌向、垂直向的位移、倾斜、扭转量,统计分析不同固位力大小对基牙位移影响的意义。结果杆式附着体在义齿500 g、930 g、1 450 g的固位力时,除垂直向位移外,差别均有统计学意义(P<0.05),1 450 g时基牙的位移、倾斜、扭转大于另两者。结论随着义齿固位力的增加,基牙的水平扭转和近远中、唇舌向的倾斜、位移也增大。

Objective To study the influence of overdenture with bar-attachment with various retention to displacement of abutment.Methods Fabricate overdentures with bar attachments with 500 g,930 g and 1 450 g retention respectively as study model——a intact maxilla and a mandible with only two canines remained. When food chip was masticated between dentitions, place food chip in posterior occlusion bilaterally. When the masticated loads were 2 kg, 4 kg, 6 kg, 8 kg, measure displacement of the abutment and calculate displacement, inclination, and torsion of the abutment in mesial-distal, labial-lingual and vertical directions respectively. Then analyze the effect of retention on displacement, inclination and torsion of abutment. Results The displacement, inclination and torsion of overdenture with bar-attachment were significantly different except in vertical direction when the retention was 500 g, 930 g and 1 450 g. It was greater in retention of 1 450 g than the other two. Conclusion Abutment displacement increase with some degree of increase of the overdenture retention.