Smile Esthetics and Rotated Maxillary Lateral Incisors

Area of Science:

• Orthodontics
• Dental Aesthetics
• Psychology

Background:

• Tooth rotations are common orthodontic issues.
• Limited research exists on layperson perception of tooth rotations.
• Understanding layperson esthetic preferences is crucial for orthodontic treatment planning.

Purpose of the Study:

• To evaluate laypersons' esthetic perceptions of varying degrees of maxillary lateral incisor rotation.
• To determine the threshold at which tooth rotation becomes esthetically unappealing to the general public.

Main Methods:

• Digital manipulation of a dental scan to create four rotation conditions (0°, 20°, 30°, 40°).
• Presentation of smile images in frontal and three-quarter views to a panel of laypeople (ages 18-30).
• Rating of smile attractiveness using a visual analog scale (VAS) and statistical analysis (ANOVA).

Main Results:

• Smiles with no rotation were rated significantly more attractive than any rotated smiles.
• A 40° rotation was perceived as significantly less esthetic compared to other conditions.
• Laypersons could not significantly differentiate between 20° and 30° rotations esthetically.
• Panelist gender did not significantly influence esthetic ratings.

Conclusions:

• Laypersons prefer naturally aligned smiles over those with rotated incisors.
• Significant incisor rotation (40°) negatively impacts smile esthetics.
• Minor incisor rotations (20-30°) do not significantly alter layperson esthetic perception.
• Gender does not play a role in the esthetic judgment of incisor rotation.