RESUMO
Objective:To investigate the stress distribution and the initial displacement of maxillary anterior teeth during en-masse retraction with clear aligner.Methods:The initial 3D finite element model of the maxillary teeth,PDL and alveolar bone was constructed by CBCT image reconstruction technique.Laser scanned image of crowns was merged with initial 3D model.The stress distribution and the initial displacement were analyzed by ANSYS Workbench when aligner was loaded.Results:The high simulation maxillary complex was constructed.Distal and lingual crown tipping of central incisors and lateral incisors were observed.The tendency of extrusion of the central and lateral incisors was consistant.The same tendency of stress distribution in PDL and initial displacement was appeared on incisors.The distal tipping movement was occurred on canine.Conclusion:Tipping movement along with extrusion can be produced by maxillary anterior teeth during en-rnasse retraction in extraction treatment with clear aligner.
