Treatment of Mandibular Prognathism with Bilateral Sagittal Split Ramus Osteotomy and Paranasal Augmentation: Mandible-to- Paranasal Bone Transfer without Additional Bone Graft Donor-Site

Chun, Yong Hoon; Hyon, Won Sok; Oh, Kap Sung

Abstract

The patients with mandibular prognathism frequently have a retrusion of the lower nasal base and around the piriform aperture. In such cases, paranasal depression or flattening gives a person a gloomy, tired, depressive and old appearance by accentuating the nasolabial folds. In this case, mandibular set back is not enough to achieve the maximum aesthetic results and facial harmony. Although severe retrusion of maxilla needs large graft for paranasal augmentation or Lefort osteotomies, mild retrusion around the piriform aperture can be restored by simple autogenous onlay bone graft. In order to correct the mild paranasal retrusion combined with mandibular prognathism, we performed sagittal split osteotomy of ramus and retropositioned the distal segment of mandible for mandibular set back. Thereafter, we harvested autogenous bone from the distal portion of a mandibular proximal segment. The harvested bone was about 1 X 2.5cm sized and sculptured in a semilunar shape to fit the paranasal region. Through two separate 1-cm upper buccal incision, the bone grafts were placed around the piriform aperture for contour restoration and fixed with screw. Our operative technique is simple and easy, moreover has no need for another donor site for paranasal augmentation. Using this method, we treated paranasal depression as well as mandibular prognathism at the same time and so, improved facial profile and contour in 5 cases. At the time of follow-up at 1 year, there has been no infection, extrusion or relapse with this technique and patients were satisfied with their aesthetic results.