Reconstruction of mandibular symphyseal defects by trifocal distraction osteogenesis: an experimental study in Rhesus

Area of Science:

• Oral and Maxillofacial Surgery
• Regenerative Medicine
• Biomaterials Science

Background:

• Mandibular symphyseal defects cause significant maxillofacial deformity and functional impairment.
• Distraction osteogenesis is an emerging technique for reconstructing craniofacial bone defects.

Purpose of the Study:

• To evaluate the efficacy of trifocal distraction osteogenesis using custom multiplanar distractors for reconstructing mandibular symphyseal defects in a rhesus monkey model.

Main Methods:

• Anterior mandibulectomy was performed on four rhesus monkeys, creating artificial symphyseal defects.
• Bilateral transport segments were created and reconstructed using custom multiplanar distractors and trifocal distraction osteogenesis.
• Serial X-rays, 3D CT scans, and histological examinations were used to assess bone regeneration and union.

Main Results:

• Successful repair of mandibular symphyseal defects was achieved in all animals, with restored anterior mandibular contours.
• Histological examination revealed perfect bone regeneration in distraction gaps and fibro-bony union between segments at 16 weeks.
• The custom multiplanar distractors facilitated simultaneous forward and inward distraction of bilateral transport segments.

Conclusions:

• Trifocal distraction osteogenesis with custom multiplanar distractors is a viable method for reconstructing anterior mandibular defects.
• This technique promotes significant bone regeneration and achieves stable union, potentially offering an alternative reconstructive approach.