Biomechanical Evaluation of the Maxilla during Maxillary Distraction Osteogenessis with the New Hybrid Distraction Device: A Finite Element Analysis
Poonsak Pisek DDS, MSc, FRCDS, M Orth RCSEd*, Somchai Sessirisombat DDS, MS, MD**, Bunyong Rungroungdouyboon PhD***
Affiliation : * Department of Orthodontics, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand ** Department of Oral and maxillofacial surgery, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand *** Department of Mechanical Engineering, Faculty of Engineering, Thammasat University, Bangkok, Thailand
Background : Patients with cleft lip and palate (CLP), who have malocclusion combined with severe skeletal Class III
problems, usually have multidimensional maxillary hypoplasia. The present study invented a new hybrid distraction device to
correct severe skeletal problems.
Objective : To evaluate biomechanical of a new hybrid distractor device during maxillary sagittal distraction osteogenesis.
Material and Method: Three-dimensional finite element skull models of a 20-year-old, non-syndromic male patient with
bilateral complete cleft lip and palate was constructed. Stress distributions and displacement of the new hybrid distractor were
analyzed using ANSYS v.10.0.
Results : The maximum stress levels were observed for both external and internal components of the new hybrid distractor
device. The values of maximum stress were not exceeding yield stress and the range of safety factor was 2.36 to 3.76. The
maxilla bone was in equilibrium balance between action force and reaction force and showed symmetrical displacement.
Conclusion : The new hybrid distractor device has enough strength during maxillary distraction osteogenesis and can
provide controlled symmetrical displacement of the maxilla.
Keywords : Maxillary distraction osteogenesis, Maxillary distractor device, Cleft lip and palate patient
