3种不同方式的双板法坚固内固定髁突矢状骨折生物力学分析

Biomechanical analysis on the fixation of mandibular condyle with sagittal fracture by double plates in 3 ways

目的:对3种双板法坚固内固定髁突矢状骨折(SFMC)行生物力学分析。方法:构建SFMC双直板(SS)、一直一L板(SL)、双L板(LL)坚固内固定三维有限元模型,对比其生物力学因素。结果:SS固定的髁突残端最大等效应力(MES)、最大总位移(MTD)和最大总转角(MTC)分别为525.475 MPa、0.902 2 mm、0.260 1°;游离端为4.425 MPa、0.882 7 mm、0.019 9°。SL固定的髁突残端为1 135 MPa、0.936 7 mm、0.126 1°;游离端为2.656 MPa、0.887 1 mm、0.016 9°。LL固定的髁突残端为2 208 MPa、0.923 8 mm、0.172 2°;游离端为14.66 8 MPa、0.876 6 mm、0.018 1°。结论:双L板生物力学分布方式合理。

Objective： To analyze the biomechanical stress distribution on the sagittal fractured of the mandibular condyle（SFMC） fixed by double plates in 3 different ways. Methods： The fixation finite element models with double straight plates （SS）, one straight and one L-form plates（ SL）, and double L-form plates（LL） were established. The biomechanical stresses on condyle were calculated with finite element analysis. Results： In the model of SS fixation the maximum equivalent stress （ MES）, maximum total displacement （MTD） and maximum total corner（MTC） of condylar stump were 525. 475 MPa, 0.902 2 mm and 0.260 1 ~ ; MES, MTD, and MTC on fractured free-end were 4. 425 MPa, 0. 882 7 mm and 0. 019 9°, respectively. In the model of SL fixation MES, MTD and MTC on condylar stump were 1 135 MPa, 0.9367 mm and 0. 126 1° ; MES, MTD and MTC on fractured free-end were 2. 656 MPa, O. 887 1 mm and 0. 016 9°, respectively. In the model of LL fixation MES, MTD and MTC on condylar stump were 2 208 MPa, 0. 923 8 mm and 0. 172 2° ; MES, MTD and MTC on fractured free-end were 14.66 8 MPa, 0. 876 6 mm and 0.018 1°, respectively. Conclusion： Double L plates fixation is a proper waY for SFMC.