Three-dimensional Finite Element Analysis Of Temporomandibular Joint In Adult Patients With Class Ii Division 1 After Single Maxillary Extract Correction

Objective: To compare and analysis the stress distribution and biomechanic ch aracters of temporomandibular joint(TMJ)of before and after single maxillary extraction treatment of adult Class II division 1 classification.Methods: The three-dim-ensional finite element models of normal,before and after single maxillary extratio-n in Class?division1 occlusion will be constructed by integrating the data of CT and MRI.And then the stress distribution in their temporomandibular joint parts wil-l be conducted after mechanical loading and boundary constraint to this three mod elsrespectively.Results: Compared with Class?~1malocclusion,the stress distribution of temporomandibular joint after orthodontic tooth extraction was more uniform,an-d no significant stress concentration area,the stress value of condylar stress is lower than before,the articular disc and the temporal bonewere larger than those of before the treatment,but the stress distribution was more balanced,similar to stress distribution characteristics of normal occlusion.Conclusion: This kind of orthodonti-c treatment program reduces the risk of temporomandibular joint disorder with Cla-ss?~1malocclusion,which is in line with the goal of orthodontic treatment.But fo-r the treatment of the former condyle has been in the posterior joint of the poster-ior part of the Class ? division 1 patients should be carefully selected maxillary single tooth extraction treatment,so as not to increase the local stress is too large and increased its risk of temporomandibular disorders.