Retrospective analysis of nasal soft tissue profile changes with maxillary surgery

Abstract

Purpose: The aim of this study was to analyze the changes in the position of the nasal and labial soft tissue profile of patients undergoing bimaxillary orthognathic surgery, with special emphasis on the effect on the nasal tip projection.

Materials and methods: The lateral cephalometric radiographs of 27 consecutive patients (16 female and 11 male patients; mean age, 22 years) who had undergone maxillary advancement and mandibular setback were studied. The pretreatment and end-of-treatment lateral cephalometric radiographs were selected. The pretreatment and end-of-treatment radiographs were superimposed on the sella-nasion plane, and the case was only included if there had been no change in sella-nasion length (ie, no growth). Analyses of Pearson correlation coefficient and stepwise linear regression tests were used to compare the cephalometric measurements at the beginning and at the end of treatment. Paired-sample t tests were also performed to analyze changes in nasolabial angle (NLA) and columella-lobular angle (CLA).

Results: The correlations between vertical movement of nasal tip, A-point, and maxillary incisal tip were important. Although there was an important correlation between nasal and incisal tip, interestingly, there was no correlation between nasal tip and A-point in horizontal movement. According to stepwise linear regression analysis, the best model for horizontal movement of nasal tip was as follows: Nasal anteroposterior movement = 0.241 + 0.188 × Incisal tip anteroposterior movement + 0.153 × Incisal tip superoinferior movement. For vertical movement of nasal tip, the best model was as follows: Nasal superoinferior movement= -1.117 + 0.399 × Incisal tip superoinferior movement + 0.323 × A-point anteroposterior movement. There was no significant relation in angular measurements of NLA and CLA before and after treatment.

Conclusion: The results of our study suggest that both horizontal and vertical movements of nasal tip were related to incisal tip and A-point movements; however, angular changes in CLA and NLA did not affect the nasal tip.