The Biomechanical Study Of Two-dimensional And Three-dimensional Fixation Of Mandibular Fractures With Finite Element Method

Objective:Three-dimensional finite element analysis of titanium mandibular fractures in different number of spatial locations of different fixation for the various operating conditions (central occlusion, ipsilateral occlusion in molars, premolars affected side occlusion, contralateral anterior occlusion, contralateral occlusion after molar) mandibular segment fault displacement, stress distribution and stress distribution of nail plate. Comparison of different fixation methods of fixed effects, clinical trials using rigid internal fixation of mandibular fracture treatment of reference.Methods:Using ANSYS software to build three-dimensional finite element model of mandible, and modify three-dimensional finite element model of the mandible, the establishment of fracture fixation of three-dimensional finite element model of mandibular symphysis, body fractures using a different number and different plate nail spatial location row two-dimensional double-plate fixation, three-dimensional double-plate fixation,two-dimensional three-plate fixation, three-dimensional three-plate fixation. Under way in different occlusal stress and displacement of fracture fragments calculated to compare the different conditions of stress fractures of fault, the displacement of fracture fragments, fixed plate stress, to evaluate the effect of a fixed manner.Result:1, mandibular body fractures:(1) Two-dimensional double-plate fixation:two plates apart 4mm and 6mm displacement of fracture fragments were:ipsilateral premolar bite 0.096391mm and 0.088464 mm. (2) three-dimensional double-plate fixation:11mm and 13mm away from the two plate displacement fracture fragments are:affected side premolar bite 0.091322mm and 0.087881 mm.(3) two-dimensional three-dimensional three-plate fixation and plate fixation:ipsilateral premolar bite 0.084659mm and 0.078288mm.2, Mental fracture:(1) Two-dimensional double-plate fixation:two plates apart 3mm,5mm and 7mm displacement of fracture fragments were central occlusion as 0.079547mm,0.078166mm and 0.076751mm. (2) three-dimensional double-plate fixation:two plates apart 10mm,12 mm and 14 mm displacement of fracture fragments were central occlusion as 0.072839mm, 0.07212mm and 0.07212mm. (3) two-dimensional three-dimensional three-plate fixation and plate fixation:the displacement of fracture fragments are central occlusion as 0.0765599mm and 0.071286mm.3, two-dimensional double-chin plate fixation and two-dimensional three-plate fixed bite force 200N in the middle of the displacement when the fracture fragments, respectively:0.153502mm and 0.153197mm. Three-dimensional double-chin plate fixation and three-dimensional three-plate fixed to the center when the bite force 210N displacement of fracture ends, respectively:0.149881mm and 0.149701mm.4, two-dimensional double-plate fixation body and three-dimensional double-plate fixation prior to grinding in the affected side when the bite force 170N displacement of fracture fragments were: 0.155248mm and 0.1466mm. Two-dimensional three-body and three-dimensional three-plate fixed plate fixed to the ground before the affected side when the bite force 190N displacement of fracture fragments were:0.160852mm and 0.148747mm.Conclusion:1, mandibular symphysis and body fractures, the patient should be split to avoid the median and ipsilateral premolar occlusion.2, below the lower margin of mandible buccal lip plate plus three-dimensional titanium plate fixation for the mandibular body and symphysis fracture is a safe and reliable fixation method, and in most cases better than the traditional two-dimensional power fixation.3, the mandibular body and symphysis fracture fixed stability than conventional three-plate dual-board, three-dimensional three-dimensional double sheet better than the board.4, for the mandibular body and symphysis fracture without injury where nerve and root the greater distance between the two plates, fixed the better.