[Three-dimensional finite element study on middle face advancement with distraction osteogenesis]

Area of Science:

• Biomedical Engineering
• Craniofacial Surgery
• Orthodontics

Background:

• Class III skeletal malocclusion presents complex challenges in craniofacial reconstruction.
• Predicting soft tissue response to surgical skeletal movements is crucial for optimal outcomes.
• Existing methods often lack precise prediction of facial soft tissue deformation.

Purpose of the Study:

• To establish a 3D finite element biomechanical model of facial soft tissue for Class III malocclusion.
• To simulate and predict facial soft tissue deformation resulting from three surgical plans: distraction osteogenesis and LeFort I, II, III maxillary complex advancement.
• To investigate the center of resistance during maxillary advancement and provide guidance for surgical planning.

Main Methods:

• Development of a patient-specific 3D finite element model based on anatomic structures.
• Simulation of distraction osteogenesis and LeFort I, II, III maxillary complex advancement.
• Calculation of facial soft tissue deformation ratios and visualization of 3D facial shape changes.

Main Results:

• The 3D finite element model successfully predicted facial soft tissue deformation for simulated surgical plans.
• The ratio of facial location deformation to free bone advancement was calculated.
• The center of resistance for LeFort I advancement was identified approximately 30 mm posterior to the soft tissue A point.

Conclusions:

• 3D finite element analysis of distraction osteogenesis provides valuable instruction for surgical protraction point and force direction.
• Predicting facial soft tissue deformation aids surgeons and patients in understanding surgical options and planning.
• This biomechanical modeling approach enhances precision in planning craniofacial surgeries for Class III malocclusion.