Clinical Anatomy in Bimaxillary Osteotomies

To perform bimaxillary osteotomies, explicit knowledge of the anatomy of the maxilla, midface to skull base and that of the lower third of the face is essential. Obwegeser described osteotomy and relocation of the maxilla in 1965 and simultaneous bimaxillary osteotomy for correction of dysgnathia in 1970 (Obwegeser, Schweiz Monatsschr Zahnheilkd 75:365–371, 1965; Obwegeser, Schweiz Monatsschr Zahnheilkd 80:347–356, 1970). The downfracture method as it is used today was mainly studied and described by Bell et al. (Int J Adult Orthodon Orthognath Surg 3(1):23–52, 1988), Bell (Modern practice in orthognathic and reconstructive surgery. WB Saunders, Philadelphia, 1992), Moloney and Worthington (J Oral Surg 39(10):1278–1282, 1981), Obwegeser (Plast Reconstr Surg 43(4):351–365, 1969), and Spiessl (New concepts in maxillofacial bone surgery. Springer, Berlin, 1976). Today, the Le Fort I osteotomy is a standard procedure for the correction of maxillary or bimaxillary malocclusion. In the anatomy of the mandible, the course of the inferior alveolar nerve and the bone structures in the area of the gonion angle play the most important role. Measurement points and anatomical orientation aids serve to transfer the virtual reality of computerized planning to the surgical site.