基于I-Scan系统的人颞下颌关节负荷分析模型的建立及初步研究

目的探讨基于I-Scan压力分布测试系统的冰鲜人颞下颌关节（TMJ）负荷分析模型的建立及其咬合加载研究。方法通过口内检查、计算机体层摄影术（CT）及磁共振成像（MRI）筛选出咬合关系及颞下颌关节正常的冰鲜头颅标本3例．利用I-Scan系统及动磁式力学加载机建立人TMJ负荷分析模型,记录并分析予前倾12°,107、214、321N加载力时的双侧TMJ上、下腔关节面压力分布情况。结果（1）建立了能即时反映TMJ关节面压力分布及接触面积的测试模型：（2）各力值加载时,关节面高压力区均位于髁突前斜面和关节结节后斜面外侧：（3）随着加载力值的增加．除左上关节腔面压力峰值在107N与214N组、214N与321N组间差异无统计学意义外（P〉0．05）．余关节腔面压力峰值均逐渐增加（P〈0．05）,但增幅不成比例;（4）各力值加载时,同侧关节腔面压力峰值,上腔均较下腔低（P〈0．05）：（5）各力值加载时。双侧对应关节腔面压力峰值．左侧均比右侧低（P〈0．05）。结论以I-Scan系统为基础建立的人TMJ关节面压力分析模型．能较为真实、直观地反映关节面的压力分布情况：予模拟加载时,压力集中区均位于髁突前斜面和关节结节后斜面外侧,冰鲜关节盘仍有一定的缓冲作用．使上腔关节腔面压力峰值均较下腔低：双侧关节的不对称性使异侧关节面压力峰值不同．

A preliminary study and development of the model for analyzing the stress distribution on temporomandibular joint based on the I-Scan system

Objective To study the establishment of the model for analyzing stress distribution on temporomandibular joint （TMJ） based on the I-Scan system. Methods Three fresh-frozen cadaveric heads with normal occlusion and TMJ were selected through oral examination, CT and MRI, I-Scan system and BOSE force machine was used to analyze the stress distribution of TMJ when it was loaded （107 N, 214 N, 321 N, 12° forward）. Results （1）The whole system was constructed and worked well. （2）Under the centric occlusion, the most pressed area was the lateral part of both posterior of the eminence and the anterior of the condylar. （3）As the loading increased, the interface peak pressure of TMJ increases （P 〈 0.05）,except for the upper articular cavity in the left side when it was under the loading 107 N VS 214 N and 214 N VS 321 N （P 〉 0.05）. （4）when loaded, the interface peak pressure in lower compartment of TMJ is greater than the upper （P 〈 0.05）. （5）Under the loading, the stress distribution in one side of TMJ is different from the other side （P 〈 0.05）. Conclusions The model based on the fresh-frozen cadaveric head and the I-Scan system could be more intuitive and realistic to analyze the stress distribution in TMJ qualitatively. In the trial condition, the most pressed area of TMJ was the lateral part of both posterior of the eminence and the anterior of the condylar, the buffering of the ice fresh disc make the interface peak pressure different between the upper and lower articularcavity, and the asymmetry of the joint make peak pressure different in the both side of TMJ.