Changes in facial movement after maxillary osteotomies

Area of Science:

• Oral and Maxillofacial Surgery
• Plastic Surgery
• Facial Anatomy

Background:

• Maxillary Le Fort I osteotomy is a surgical procedure to reposition the maxilla.
• Facial movement during smiling is crucial for aesthetic outcomes.
• Understanding the impact of osteotomy on facial dynamics is essential for surgical planning.

Purpose of the Study:

• To determine how maxillary Le Fort I osteotomies affect facial movement during smiling.
• To compare the effects of different maxillary repositioning directions on smile dynamics.

Main Methods:

• Twenty patients undergoing maxillary Le Fort I osteotomy were divided into two groups based on repositioning direction (superior/posterior vs. anterior/inferior).
• Videographic analysis using the Johnson Maximal Static Response Assay evaluated four facial landmarks during a maximal smile.
• Preoperative and postoperative assessments (3-8 months) were conducted.

Main Results:

• Superior/posterior repositioning (Group A) led to a statistically significant decrease in movement at the cheilion (C) and intermediate (Im) points.
• Anterior/inferior repositioning (Group B) resulted in a statistically significant increase in movement at the alar base (A), cheilion (C), and intermediate (Im) points.
• No significant changes were observed at the labrale superioris (Ls) point in Group A, and only a non-significant increase was noted in Group B.

Conclusions:

• Anterior/inferior maxillary repositioning lengthens facial musculature, increasing facial movement during smiling.
• Superior/posterior maxillary repositioning reduces facial musculature length, decreasing facial movement during smiling.
• These findings provide insights into the biomechanical effects of maxillary osteotomies on smile aesthetics.