Dynamics of a smile in different age groups
Related Experiment Video
Updated: May 19, 2026

Dynamic Digital Biomarkers of Motor and Cognitive Function in Parkinson's Disease
Published on: July 24, 2019
Patil Chetan1, Pradeep Tandon, Gulshan K Singh
1Department of Orthodontics and Dentofacial Orthopaedics, Faculty of Dental Sciences, CSM Medical University, Lucknow, UP, India. drchetpat85@yahoo.co.in
Objective:
To evaluate smile in different age groups and to detect gender differences in smile.
Materials And Methods:
Digital videographic records of 241 randomly selected subjects were obtained for smile analysis. The subjects were divided into four groups by age (15-20 years, 21-30 years, 31-40 years, and 41-50 years). Each group was further subdivided by gender. After 41 subjects were excluded, the smile dimensions of 200 subjects were analyzed by two-way multivariate analysis of variance (MANOVA) with Duncan's multiple range post hoc test.
Results:
All dynamic measurements (change in upper lip length, upper lip thickness, commissure height, and intercommissural width from rest to smile) decreased with age in both males and females. Changes in upper lip length and commissure height on smiling were greater in males as compared with females of the same age groups. Changes in intercommissural width on smiling were greater in females as compared with males in all age groups.
Conclusion:
Smile changes with increase in age, and the changes differ between males and females. Females had a wider smile as compared with males of similar age groups.
More Related Videos
19:53Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
07:14Investigating the 'Uncatchable Smile' in Leonardo da Vinci's La Bella Principessa: A Comparison with the Mona Lisa and Pollaiuolo's Portrait of a Girl
Published on: October 4, 2016
Related Concept Videos
Uniform Distribution
Teeth
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...
Muscles for Facial Expressions
Facial Feedback Hypothesis
Three Developmental Domains
Physical Development
Physical processes, also known as maturation, encompass the biological changes that occur across an individual's life. These changes begin with genetic inheritance and continue through various stages, including growth in height and weight,...
Introduction to Developmental Psychology