Esthetic dental features, especially the maxillary anterior teeth, significantly influence perceived attractiveness. Gingival recessions can negatively affect smile esthetics, particularly when asymmetrical.
This study aimed to investigate the perception of dentists and non-professionals regarding subtle variations in the apically displaced soft tissue surrounding a lateral or central incisor.
Based on an ideal image of the esthetic zone, asymmetrical modifications of either a central or lateral incisor in the maxillary anterior were created and used in a digital survey asking participants to assess the overall appearance of the smile, using a visual analog scale (VAS). The dental expertise, age, and gender of the participants were recorded. For each image, the question was posed to identify if any of the teeth caused a visible irritation. The mean results of each tooth alteration and the correlation between dental expertise were statistically analyzed.
A total of 114 participants were polled. There was a significant difference in the esthetic perception between the central and lateral incisors (p < 0.001). The perception threshold for a noticeable asymmetrical recession was 1.2 mm for the central and 2.0 mm for the lateral incisor. Gender and age showed no significant difference in the esthetic evaluation, and dental expertise was only significantly different for larger recessions (p < 0.05).
The asymmetric changes were more noticeable for the central incisor than the lateral incisor. A unilateral recession change of 0.8 mm did not appear to influence the assessment of the overall smile. The dental expertise, age, or gender of the participants did not significantly correlate with a stricter esthetic perception.
The present study highlights that the perception of unilateral recession changes in the anterior maxilla varies between central and lateral incisors, with lateral incisor recessions being less impactful on the overall appearance of the smile. These findings suggest that small gingival changes can be acceptable for the overall esthetic outcome, underscoring the importance of discussing patient expectations and treatment options before restoration or orthodontic treatment and prioritizing the gingival margin of the central incisor which appeared more noticeable.

