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Author Spotlight: Development of a Novel Finite Element Analysis Model for Improved Orthognathic Surgical Techniques
Published on: October 20, 2023
Comparative biomechanical analysis of three rapid maxillary expanders in BCLP patients: A three-dimensional finite
Shuoyi Hui1, Jianing Liu2, Yanqi Zhang1
1State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, Shaanxi, China.
Abstract:
Maxillary expansion in bilateral complete cleft lip and palate (BCLP) poses unique biomechanical challenges due to disrupted anatomy and scarred sutures. This finite element study compared three expander types-conventional Hyrax, pre-positioned Hyrax, and fan-shaped-in a patient-specific BCLP model derived from CBCT data. We evaluated 3D dentoalveolar displacement, craniofacial suture strain, and periodontal ligament (PDL) stress. The fan-shaped expander achieved greater anterior expansion and vertical control but induced higher von Mises stress and buccal tipping, raising concerns over periodontal safety. In contrast, conventional and pre-positioned Hyrax expanders produced more uniform force distribution and better posterior anchorage control. Skeletal displacement patterns were comparable across models. The findings suggest that fan-shaped expanders may be beneficial for cases with severe anterior constriction but require caution due to stress concentration risks, while Hyrax variants offer biomechanically safer alternatives for moderate expansion needs. This study provides novel, evidence-based insight into expander selection in complex cleft patients and emphasizes the importance of individualized, morphology-driven appliance design.
