Gassmann C J, Nishioka G J, Van Sickels J E, Thrash W J
University of Texas Health Science Center, Department of Oral and Maxillofacial Surgery, San Antonio 78284-7908.
J Oral Maxillofac Surg. 1989 Sep;47(9):926-30. doi: 10.1016/0278-2391(89)90375-3.
Fifty patients who had undergone Le Fort I maxillary osteotomies were studied. Cephalograms were available preoperatively and at least 6 months postoperatively. Soft-tissue analysis of the nasal profile was done employing three angles commonly used in the photometric analysis performed for rhinoplasty: nasal tip projection angle, columellar angle, and supratip break angle. Maxillary movement was assessed in two ways: 1) horizontal and vertical component vectors of A-point movement were calculated, and 2) maxillary rotation, defined as the change in the angle of a line drawn from the anterior nasal spine to the posterior nasal spine relative to the anterior cranial base, was calculated. The component vectors of A-point movement and maxillary rotation were then used as predictor variables for change in the soft-tissue angles in a multiple-regression analysis. A weak correlation was found between A-point movement in both the horizontal and vertical dimensions and the nasal tip projection angle. When A-point was moved in an anterior and superior direction, the nasal tip rotated up. The converse was true with movement in the posterior and inferior direction. Only A-point movement in the horizontal dimension had a significant relationship with columellar angle. When A-point was moved in an anterior direction, columellar angle increased. This study shows that prediction of the soft-tissue profile of the nose following maxillary surgery is difficult.
