Finite Element Analysis of Trans-Sutural Distraction Osteogenesis on the Nasomaxillary Complex in Adolescents with Cleft Lip and Palate.

Introduction: Trans-sutural distraction osteogenesis (TSDO) has emerged as a promising treatment for midfacial hypoplasia. However, the mechanical effects on craniofacial structures remain insufficiently understood.

Material & method: Finite element models (FEM) of two adolescent patients with cleft lip and palate (CLP) (aged 10 and 11) were reconstructed from CBCT data. TSDO was simulated by applying symmetrical traction forces to the maxilla. A modified surgical intervention, transanterior maxillary wall osteotomy, was also modeled to assess its biomechanical impact. Displacement and stress distribution were evaluated using total deformation, first and third principal stresses, and Von-Mises stress.

Results: TSDO induced forward displacement of the midface, especially in the alveolar process, with additional movement in the nasal, infraorbital, and zygomatic regions. Stress concentrations were observed around the traction hooks, nasomaxillary suture, and nasal septum. The cleft palate model exhibited more asymmetrical and uneven stress distribution. The simulated transanterior maxillary wall osteotomy significantly reduced stress in the nasal-infraorbital-zygomatic region while preserving maxillary advancement.

Discussion: TSDO effectively advances the midface in CLP patients but may result in undesirable protrusion in the nasal-infraorbital-zygomatic region. Transanterior maxillary wall osteotomy shows potential for mitigating these effects.