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Published on: April 21, 2011
Clockwise and Counterclockwise Le Fort I Movements Influence Nasolabial Morphology Differently
Rajendra Sawh-Martinez1, Alex M Lin1, Christopher R DeSesa1
1From the Department of Surgery, Section of Plastic Surgery, Yale University School of Medicine; and the Frank H. Netter MD School of Medicine, Quinnipiac University.
Background:
Le Fort I maxillary advancements affect nasal proportions. However, there are no data on the three-dimensional nasal changes that occur with differential lateral plane adjustment (clockwise and counterclockwise movements) during Le Fort I maxillary advancements. This study analyzes and compares nasolabial soft-tissue changes after Le Fort I clockwise and counterclockwise repositioning.
Methods:
Single-piece Le Fort I advancements were included. A retrospective study of patients split into clockwise and counterclockwise groups was performed. Preoperative and postoperative three-dimensional photographs (VECTRA 3D) were analyzed. Nasolabial anthropometric measurements were recorded using Mirror software. Statistical analysis involved paired t test to compare preoperative and postoperative measurements.
Results:
Twenty-four patients were evaluated (12 per group), with 22 distinct nasolabial relationships measured. Counterclockwise movement showed a statistically significant increase in alar width (3.6 mm; p < 0.001), alar base width (1.6 mm; p = 0.009), oral width (3.2 mm; p = 0.02), and lip projection (3.4 mm; p = 0.04). Clockwise movement showed no statistically significant changes, with the largest position changes noted in alar width (2.7 mm; p = 0.07) and alar base width (1.7 mm; p = 0.09).
Conclusions:
Clockwise and counterclockwise Le Fort I advancements have a different effect on postoperative nasolabial morphology. Counterclockwise movements exhibit significant changes, widening the alar base and width and the oral and philtral widths. The impact on the nostril morphology and columella was similar between the groups. The differential impact on nasolabial appearance is important to recognize for treatment planning and patient counseling.
Clinical Question/Level Of Evidence:
Therapeutic, III.
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