A Comparison of Varying Golden Proportion on Smile Aesthetic Perception Between Patients, Orthodontists and...

The study aimed to assess how variations in the golden proportion (GP) influence aesthetic perception among three groups: orthodontic patients, orthodontists and restorative dentists. It sought to determine a range of aesthetic tolerance for lateral incisors and canines, addressing gaps in previous literature.

Our cross-sectional study included 128 participants (orthodontic patients and clinicians). Standardised smile photographs were digitally altered from a range of 52%-77% at 5% intervals. Participants rated photos on a five-point Likert scale. The range was determined by analysing scores using the interquartile range (IQR), focusing on photographs with a median ≥3 and outliers were then removed. Kruskal-Wallis and Mann-Whitney U tests compared groups, while Spearman correlation evaluated gender and experience.

Patients accepted a broader range of GP (52%-77%) compared to orthodontists (62%-67%), operative dentists (57%-72%) and prosthodontists (62%-72%). Between-group differences were significant for the majority of photographs (p  < 0.05), with male photographs reaching high significance (p < 0.001). Post hoc analysis confirmed consistent differences between patients and professionals (p < 0.001), while fewer differences existed among professional groups, showing weak to moderate agreement (rb = 0.257-0.396). Gender (p > 0.05, except for two images: p = 0.013, R = 0.255) and clinical experience (p > 0.05) did not significantly influence aesthetic preferences.

The study concludes that the GP is more applicable as a range rather than a fixed value. Patients showed a wider aesthetic preference than clinicians. The patients' perceptions were closer to restorative dentists than orthodontists (p < 0.001), likely reflecting differing clinical objectives. The inter-professional agreement observed supports the need for a multidisciplinary approach in aesthetic treatment planning.

The clinical significance of the study lies in its potential to improve treatment outcomes in both aesthetic dentistry and orthodontics. The study highlights the need for a flexible, range-based approach while using the GP to achieve diverse aesthetic demands. The importance of interdisciplinary collaboration between restorative dentists and orthodontists in procedures such as space closures and teeth remodelling is emphasised, ultimately improving aesthetic and functional outcomes. It also acknowledges the variability in aesthetic perception among different cultural and ethnic backgrounds.