Combining the Anterior Subapical Osteotomy With Traditional Orthognathic Surgery

Abstract

The anterior sub-apical osteotomy (ASO) is a valuable procedure in the treatment of certain dentoskeletal deformities. Kole popularized the mandibular ASO in 1959. It can be used in the maxilla and mandible often in conjunction with extraction of premolars. This technique has been performed on its own for correction of dentoalveolar protrusion as well as skeletal-dental open bite and deep bite deformities while maintaining chin position and improving labiomental relationships. It can also be used in combination with Le Fort I (LFI) and bilateral sagittal split osteotomies (BSSO) with benefits including improved lip relations and labiomental esthetics, chin contour and incisor proclination. In addition, it is well known that large mandibular setbacks can increase the likelihood of airway compromise and the mandibular ASO can circumvent the need for large posterior repositioning. The purpose of this study is to present the utility of combined mandibular ASO with the LFI, BSSO and maxillary ASO as an approach for addressing certain dentoskeletal deformities. This study includes 13 patients (4 male, 9 female) of an average age of 19.8 years (range 13 to 28 years), 7 with clefts, 1 Crouzon syndrome and 5 dentoskeletal deformities. Six patients underwent mandibular ASO and LFI; 4 underwent mandibular ASO, LFI and BSSO; 2 patients underwent bi-maxillary ASO, and 1 maxillary ASO and BSSO. All procedures were completed by a single surgeon (JWP). The patients were followed a minimum of 2 years after surgery. Cephalometric changes before and after surgery were analyzed using a paired t test (p<0.05). The results demonstrated a favorable improvement in the mandibular incisor to mandibular plane angulation, increased distance between pogonion and the tip of the lower incisor, decreased distance of the lips to the esthetic line and increase in the depth of the labiomental fold. Based on the measured parameters all patients had an improvement in their skeletal, dental and soft tissue relations. The combination of the mandibular ASO with other maxillary and mandibular osteotomies is a useful surgical option in the treatment of certain dentoskeletal deformities.