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Updated: May 15, 2026
07:32
Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
[Preliminary three-dimensional analysis of posed smile].
Jing Li1, Yi-Jiao Zhao, Yi Liu
1Department of Orthodontics, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.
Summary
Posed smiles are asymmetric, with distinct facial feature region changes. Women exhibit more significant lip displacement during smiles than men.
Area of Science:
- Plastic surgery
- Craniofacial surgery
- Aesthetic medicine
Context:
- Understanding facial dynamics is crucial for aesthetic and reconstructive procedures.
- Quantifying smile-induced facial changes provides objective data for clinical applications.
- Previous studies often used 2D analysis, limiting detailed 3D understanding.
Purpose:
- To conduct a three-dimensional (3D) quantitative analysis of facial feature region changes during posed smiles.
- To investigate the asymmetry and variations in displacement during smiling.
- To compare gender-specific differences in smile dynamics.
Summary:
- 3D facial scans of 44 volunteers (26 women, 18 men) at rest and during posed smiles were analyzed.
- Quantitative and qualitative 3D analyses revealed significant changes in the cheilion, zygomatic area, and lower lip.
- The overall changing area during a posed smile was 29.65 ± 8.40%, with left-right asymmetry noted.
Impact:
- Posed smiles demonstrate inherent asymmetry in facial feature displacement.
- Women showed greater displacement in the nasolabial fold (4.49 ± 1.51 mm) compared to men (3.25 ± 1.75 mm).
- Findings offer valuable insights for surgical planning and facial animation technologies.
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