Related Experiment Video
Updated: Aug 7, 2026
09:26
Quantification of Orofacial Phenotypes in Xenopus
Published on: November 6, 2014
Upper lip asymmetry in adults during smiling
1Department of Oral and Maxillofacial Surgery, Virginia Commonwealth University, School of Dentistry, Richmond 23298-0566, USA. DMLASKIN@VCU.EDU
Summary
This study found that 8.7% of adults exhibit upper lip asymmetry when smiling, a condition known as upper lip canting. This finding is important for cosmetic and orthognathic surgery planning.
Area of Science:
- Dentistry
- Plastic Surgery
- Facial Aesthetics
Background:
- Facial asymmetry can impact patient satisfaction with cosmetic and reconstructive surgery.
- Understanding the prevalence of specific asymmetries, like upper lip canting, is crucial for surgical planning.
Purpose of the Study:
- To determine the incidence of upper lip asymmetry during smiling in an adult population.
- To assess the prevalence of upper lip canting in relation to occlusal plane cant.
Main Methods:
- Evaluated 210 students aged 21-44 years for upper lip asymmetry while smiling.
- Excluded subjects with an occlusal plane cant.
- Assessed upper lip asymmetry in the remaining 195 subjects through repeated smile evaluations.
Main Results:
- Fifteen subjects (7.1%) were excluded due to occlusal plane cants.
- 17 out of the remaining 195 subjects (8.7%) displayed upper lip asymmetry.
- The asymmetry observed was secondary to upper lip canting.
Conclusions:
- Clinically significant upper lip canting occurs in 8.7% of adults during smiling.
- This prevalence, though not high, warrants consideration in orthognathic and cosmetic surgical procedures.
- Upper lip asymmetry during smiling is a relevant factor in facial aesthetic evaluations.
Related Concept Videos
01:35Asymmetric Lipid Bilayer
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
01:15Teeth
The formation of teeth, also known as odontogenesis, is a complex process that begins in utero, around the sixth week of embryonic development. There are three stages to this process: the bud stage, the cap stage, and the bell stage.
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
01:26Assessment of the Mouth
A thorough mouth assessment, including inspection and palpation of the lips, gums, tongue, tonsils, uvula, and pharynx, is crucial in detecting potential health issues. Diseases ranging from oral cancer to systemic conditions like diabetes could be identified early through careful oral examination. This article provides a detailed guide on conducting a comprehensive mouth assessment.
Mouth Inspection
The inspection begins with visually examining the mouth for symmetry, color, and size.
Mouth Inspection
The inspection begins with visually examining the mouth for symmetry, color, and size.
01:24Facial Feedback Hypothesis
Charles Darwin proposed that facial expressions are an evolutionary adaptation for communication. He argued that these expressions are not influenced by culture but are universal across species. For example, a snarling expression with exposed teeth signals a threat in many animals, including humans. Darwin also suggested that displaying an emotion can intensify the feeling. Smiling, for example, could enhance one's sense of happiness. This idea laid the foundation for understanding the role of...