Maryam Azimi
Maryam Dinparvar
Hosna Teimourian
Maryam Farhadian

Background: The width ratio of teeth is an important factor in dental and facial esthetics. The Golden proportion (۶۲%) and the recurring esthetic dental proportion (RED) are two theories in this field that have been suggested to create harmony among anterior teeth. These have rarely been studied among the Iranian population. Objectives: The aim of this study was to evaluate the Golden proportion and RED proportion in students, staff, and patients of Shahed dental school. Patients and Methods: This study was conducted with ۱۱۶ subjects in Shahed dental school photographs of the subject’s anterior teeth were taken from the frontal view. The perceived width ratios of canine to lateral incisor and lateral incisor to central incisor were calculated. In this study, the Golden proportion was evaluated within the range of ۰.۵۵ – ۰.۶۴. To evaluate the existence of the RED proportion in each subject, the width ratio of canine to lateral incisor was compared with the width ratio of lateral incisor to central incisor. Results: The Golden proportion existed in ۲۵% of the perceived width ratios of lateral incisor to central incisor, and ۲.۱% of the width ratios of canine to lateral incisor in natural dentition. The RED proportion existed in ۱۸.۵% of subjects, and the most recurring proportion was ۰.۷۳ in these subjects. Conclusions: The Golden proportion and the RED proportion cannot be used as constant proportions to create a harmonious proportion throughout the width of maxillary anterior teeth.