Background: Dentofacial-deformities are traditionally treated by maxillary and mandibular osteotomies conducted separately or simultaneously. Recently, distraction osteogenesis (DO) has become an irreplaceable part of the surgical armamentarium. Our aim is to describe a combined surgical technique of simultaneous maxillary Le-Fort I advancement as a skeletal template for mandibular surgical repositioning by means of bilateral-sagittal-split-osteotomy (BSSO) with a curvilinear distractor based on a preliminary computerized presurgical prediction.
Methods: Seven patients, all suffering from obstructive sleep apnea, who presented with a large skeletal open bite and severe mandibular retrusion were included. The presurgical procedure included orthodontic preparation and computerized planning. After performance of Le-Fort I maxillary advancement, a BSSO predistraction procedure was initiated facilitating final mandibular position as dictated by the surgical splint. Thereafter a curvilinear distractor was attached to the osteotomized mandible and the jaw was released allowing the distractor to be expanded freely until it could be fixed to the distal component. Then a simultaneous curvilinear DO was conducted and the respective spiral movement of the mandible was achieved. Lateral cephalometric X-rays, before and after surgery, were traced by plotting different skeletal landmark points and were then analyzed.
Results: All patients tolerated the procedures well through completion. The average vertical change at point I for the maxillary and mandibular incisors and at points A and B was similar (3.14–4.21 mm). However, the average horizontal changes at points I (of the mandibular incisors) and B were almost 5 times larger (14.28 mm and 15 mm, respectively).
Conclusion: A simultaneous maxillary and mandibular surgical advancement protocol using maxillary Le-Fort I and mandibular BSSO with curvilinear DO is a useful and accurate technique for dentofacial-deformity management. This technique allows the surgeon to refine the reliability of the distraction and the final occlusion. Additionally this technique is preferable in terms of operation-time and expanses.
Key words : Le-Fort I; BSSO; curvilinear distraction