The Assessment of External Nasal Valve Efficiency After Le Fort I Surgery.

BACKGROUND: The present study investigated how external nasal valve function is affected after Le Fort I osteotomy using external nasal valve efficiency (ENVE) index. MATERIALS AND METHODS: Twenty-one patients who underwent Le Fort I osteotomy with or without mandibular osteotomy were included in the retrospective study. Preoperative and postoperative standardized videos of basal view of the nose during breathing were recorded, and 2 screenshots were taken, 1 in the resting position and the other after deep inspiration. External nasal valve efficiency was calculated at preoperative and postoperative periods for each patient. RESULTS: Of the 21 patients, 12 were women and 9 were men (mean age, 26.63 ± 8.20 years). The mean ENVE index was 0.75 ± 0.16 for the preoperative period and 0.82 ± 0.17 for the postoperative period. There was a significant difference between these values ( P = 0.002). When the correlation of the ENVE with maxillary movements was analyzed, the ENVE was negatively affected by maxillary impaction ( P = 0.011, r = -0.540). CONCLUSIONS: These findings imply that Le Fort I osteotomy positively affects the ENVE index. However, because of the antagonistic relation between maxillary impaction and ENVE, higher maxillary impaction amounts or isolated maxillary impaction should be carefully planned in patients with low ENVE index.

Analysis of Inferior Nasal Morphology and Nostrils following Le Fort I Osteotomy.

OBJECTIVE: This study aimed to investigate the soft tissue parameters related to inferior nasal morphology and nostril shape and investigate the change at nostril types according to the Modified Topinard System following maxillary surgery. MATERIALS AND METHODS: Thirty-five patients who underwent Le Fort I osteotomy with or without mandibular osteotomy were included in this retrospective study. Presurgery (T1) and postsurgery (T2) measurements which were the angle between the longitudinal axis of left and right nostril, nostril length, nostril width, alar width, alar base width, columella length, and columella width, were measured on computed tomography images. Nostril types according to Modified Topinard System and nostril shapes were also examined. RESULTS: Following Le Fort I surgery, there was a significant increase in alar base width, alar width, and angle between the longitudinal axis of the left and right nostril (P<0.05). Nasal tip protrusion was decreased with significance (P=0.022). Multiple linear regression analysis showed that every 1 mm maxillary impaction amount leads to a 3.34° increase in the angle between the longitudinal axis of the left and right nostrils (P=0.03, adjusted R2=0.21). Nostril type classification according to Modified Topinard System was changed significantly (P=0.000). CONCLUSION: Surgeons should be aware of the risk of postoperative nonaesthetic results in Modified Topinard System's borderline cases. Modified Topinard classification may be included in preoperative orthognathic planning from the bottom view.

Evaluation of parameters related with upper lip aesthetics and dynamic smile following Le Fort I osteotomy.

OBJECTIVE: The present study aimed to investigate how upper lip aesthetic and dynamic smile parameters are changed following a Le Fort I osteotomy. METHODS: Twenty-seven patients who underwent Le Fort I osteotomy with or without mandibular osteotomy were included in this retrospective study. Upper lip aesthetic parameters which were Cupid's bow angle, lip angle, lip length, lip width, philtrum width and lip corners were evaluated on pre and postoperative rest photos using Image J software. Lip corner movement direction, buccal corridor area with respect to canine and last visible tooth were also measured on posed smile photos with respect to dynamic smile evaluations. Measured variables were submitted to statistical analysis and significance level was determined as 0.05. RESULTS: There was a significant reduction in buccal corridor area according to last visible teeth for right and left side at postoperative period. However, buccal corridor area with respect to canine for the right and left side was not significant. The angle between the lip corner movement direction and Y-axis of the face for the right and left sides was not significant between pre and postoperative period. The changes in this angle were not also correlated with the changes in buccal corridor area and maxillomandibular movements. Not only the Cupid's bow angle, lip angle but also lip length, lip width, philtrum width and lip corner have not been changed significantly. CONCLUSION: Buccal corridor area investigated in dynamic smile shows significant improvement after orthognathic surgery especially in the means of maxillary impaction. Lip corner movement during smile was not associated with the changes in buccal corridor area. Landmarks around perioral area in static state were affected clinically with no statistical significance following the surgery.

Analysis of Gull in Flight Appearance and Related Parameters Following Le Fort I Osteotomy.

ABSTRACT: The present study aimed to investigate how "Gull in Flight" appearance and alar-columellar relationship change following maxillary surgery. Thirty-three patients who underwent Le Fort I osteotomy with or without mandibular osteotomy were included in this retrospective study. Measurements which were angle of columella triangle, alar-rim angle, columella lobular angle, and distance of points forming "Gull in Flight" appearance were evaluated on pre and postoperative frontal and lateral photos of patients. Data was submitted to statistical analysis and significance level was determined as 0.05. Following Le Fort I surgery, distance of points forming "Gull in Flight" appearance with respect to canthus was decreased significantly (P < 0.05). Positions of these points to each other were not changed (P > 0.05). Every 1 mm maxillary impaction led to 0.58 mm reduction in y3 (the distance from the point that illustrates Gull's body) (P = 0.032). There was a decrease in angle of columella triangle, alar-rim angle and increase in columella lobular angle. However, these changes were not found significant (P > 0.05). Angle of columella triangle was increased 2.51 degree for every 1 mm maxillary advancement (P = 0.028). In conclusion, maxillary surgery had an impact on nasal region from frontal view. However, "Gull in Flight" appearance which is one of the aesthetic parameters in nose was not changed following maxillary surgery.

Changes of Stress Distributions Around Pterygomaxillary Junction With Different Osteotome Angulations.

The aim of this study was to investigate how the alteration of the angulation of osteotome at pterygomaxillary junction affects lateral pterygoid plate, maxillary tuberosity, palatal surface of maxilla, palatine bone and body of sphenoid bone. Following reconstruction of 3D modelling of maxilla, Osteotomes' tip was angulated 45 and 90 to sagittal plane to simulate pterygomaxillary osteotomy. Finite element analyses (FEA) was performed and Von Misses stress distributions were analyzed for two different angulations. Independent sample t test was used to compare differences between 45 and 90 angulations. Von Misses stress values on lateral pterygoid plate were higher in 45 angulation (0.71 ±â€Š0.21 MPa) than 90 angulation (0.54 ±â€Š0.28 MPa). This difference was statistically significant (P < 0.01). Placement of osteotome's tip with 90 angulation had higher stress value than 45 angulation on maxillary tuberosity region. However; difference wasn't significant (P = 0.44). Stress values on body of sphenoid bone were 0.45 ±â€Š0.17MPa for the case of 90 angulation and 0.19 ±â€Š0.09MPa for 45 angulation. Difference between these values were statistically significant (P < 0.01). Possible risk of unfavourable lateral pterygoid plate fracture and complications related with body of sphenoid bone during pterygomaxillary osteotomy was remarkably increased in case of narrow angulation (45). Keeping osteotome at right angle with sagittal plane may avoid these complications.