Related Experiment Video
Updated: Jan 25, 2026

Aesthetically Enhanced Silica Aerogel Via Incorporation of Laser Etching and Dyes
Published on: March 12, 2021
The influence of varying maxillary central incisor vertical dimension on perceived smile aesthetics
Elis Janaina Lira Dos Santos1, Alana Moura Xavier Dantas2, Raíssa Marçal Vilela3
11 Department of Prosthodontics and Periodontics, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil.
Objective:
To evaluate patient perception of the smile focused on analysis of the upper incisors.
Design:
Cross-sectional study.
Setting:
Department of Clinical and Social Dentistry at Federal University of Paraíba, João Pessoa, Brazil.
Participants:
The sample consisted of 135 individuals (73 women and 62 men).
Methods:
Images with different characteristics associated with the incisal edges were shown at random and analysed using a Likert scale. Data were analysed using the Chi-square test or Fisher's exact test with a statistically significant difference ( P < 0.05).
Results:
Smile I (difference of 1.5 mm in relation to the central incisor and lateral) was considered the most aesthetic, while Smile III (no difference in height between the central and lateral incisors) was the least aesthetic. A significant difference was found between perception of smile II (difference of 1 mm in relation to the central incisor and lateral) and age groups ( P < 0.005), with 31% (n = 13) of individuals aged 45-64 years considering smile II as not pleasant, 4.4% (n = 2) aged 15-24 years and 8.3% (n=4) aged 25-44 years and 4.4% (n = 2) aged 15-24 years considering the same. A significant difference was also found in relation to educational background of the assessor and smile perception, with smile III ( P = 0.0441) and smile IV ( P = 0.0053) considered the most aesthetic ( P = 0.0116).
Conclusion:
The smile considered most attractive among the sample was that with 1.5 mm steepness between the central and lateral incisors, while a flat smile arc was considered least attractive.
Related Concept Videos
Perceiving Loudness, Pitch, and Location
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by...
Gradually Varying Flow
Rapidly Varying Flow
Vertical Curve: Problem Solving
Support Reactions in Three Dimensions
Ball and Socket Joint is one of the supports allowing free rotation about any axis. This freedom of rotation is...
Relative Velocity in One Dimension

