Comparison of Maxillary Central Incisor, Crown Angulation and Tooth Size Variation in Aesthetic and Non-aesthetic Smiles- A Cross Sectional Study

Background An attractive smile is often attributed to incisor alignment and proclined or retroclined incisors could contribute to a less aesthetic smile. Objectives This study was aimed to evaluate the maxillary central incisor crown inclination, crown angulation and tooth size variation in aesthetic and unattractive smiles. Methods The study was conducted among ۱۰۰ females (equally divided into aesthetic and unaesthetic smile groups), aged between ۱۵ - ۲۵ years, with Angle’s Class I normal occlusion and balanced profiles. Variations in maxillary central incisor crown inclination and angulation were measured on lateral cephalograms, photographs and the study models of the subjects. Variations in tooth morphology were also evaluated by measuring crown height and width in both groups. Mann-Whitney U test was performed to evaluate the difference between the aesthetic and unaesthetic smiles. P < ۰.۰۵ was considered as significant. Results This study showed that incisor angulation was significantly higher in the unaesthetic group compared to the aesthetic group (P < ۰.۰۰۱). However, there was no statistically significant difference for the incisor inclination relative to the Palatal Plane between the aesthetic and unaesthetic smile groups (P = ۰.۰۸۶). In addition, there were significant differences between the aesthetic and the non-aesthetic groups regarding the central incisor height (P < ۰.۰۵). Conclusions The findings of this study indicate that the possible variations in aesthetics are related to the ethnic elements that are associated with differences in crown angulations, as well as tooth size.

کلیدواژه ها:

Smile ، Maxillary Incisors ، Crown Angulations ، Crown Inclinations