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骨折轴向分级加压应力松弛的测量与分析
Measurement and analysis on the decline of "prestressing"at fracture site with axial interfragmental gradient compression
【摘要】 目的 本研究用18 根新鲜离体湿骨( 均分三组) 形成人工骨折, 作附设钢丝张力带的分级加压固定,A 组轴向压力98 .62 ±10 .08N、B 组137 .93 ±4 .20N、C 组169 .20 ±5 .78 N; 重复加压, 轴向压力122 .41 ±16 .07 N。方法 利用电阻应变测量技术记录分析各组压应力随时间变化规律, 并作组织学对照观察。结果 三组加压应力均随时间逐步衰减, 组间总衰减率无显著性差异, 衰减幅度约为14 % ~16 % 。应力衰减约持续24 小时, 加压后第1 小时内衰减幅度约为总衰减量的1/3 ;4 小时内约达总衰减量的2/3 ;10 小时以后, 应力呈缓慢衰减。重复加压后, 应力衰减幅度1 .43 % ±0 .53 % , 约相当于初始加压总衰减量的1/10 。结论 组织学分析显示在本实验设定的压力下骨细微结构未出现明显形态改变
【Abstract】 Objective To detect the naturally change of prestress on the fracture ends.Methods Eighteen freshly harvested sheep tibiae divided into group A, B and C in equal numbers were fractured and imposed prestressing at fracture ends with tension device and plates. The interfragmental pressure was exerted 98.62 ± 10.08 N for group A, 137.92 ± 4.20 N for group B and 169.20 ± 5.78 N for group C. Strain gauge measurement technique was applied to record the floating of prestressing until compressure was constant. Results Prestressing had a gradual decrease during the first 24 hours, but there was no significant in the rate of prestressing decline among three groups. The degree of decline was approximately 14%~16% in total. By the end of first hour prestressing decreased sharply by 1/3, by the end of fourth hour only 1/3 of prestressing remained, then a constant prestressing was gradually arrived.The decline rate of prestressing in repeat compression was shown as 1.43 %± 0.53 % which was about 1/10 of the original rate.Conclusion The further histological examination showed no change of bone microstructure at the fracture ends at the given conditions.
- 【文献出处】 现代口腔医学杂志 ,JOURNAL OF MODERN STOMATOLOGY , 编辑部邮箱 ,1999年04期
- 【分类号】R318.01
- 【被引频次】2
- 【下载频次】50