Analysis of the golden proportion and width/height ratios of maxillary anterior dentition in patients with lateral incisor agenesis.

OBJECTIVE   The purpose of this study was to assess the presence of the golden proportion (GP) in the facial view tooth-to-tooth width proportion of the six maxillary anterior teeth and to evaluate the width/height (W/H) ratios of the incisors of patients with maxillary lateral incisor (LI) agenesis treated either with implants or orthodontically (by moving canines into the position of the laterals, recontouring them, and placing composite restorations over the repositioned teeth). MATERIALS AND METHODS   Forty-eight patients with LI agenesis were divided into four experimental groups: unilateral recontouring group (N = 10), bilateral recontouring group (BRG, N = 18), unilateral implant group (UIG, N = 10), bilateral implant group (N = 10), and a control group (CG, N = 25) of patients without agenesis. GP ratios were determined on patients' dental casts placed over Levin's grids, whereas W/H ratios were measured directly on the casts and a millimeter ruler to determine these distances. Statistical analysis was performed with Shapiro-Wilk, Kruskal-Wallis, Mann-Whitney, Friedman, and Wilcoxon tests (p < 0.05). RESULTS   The incidence of GP in the tooth-to-tooth width proportions was significantly different between groups and more commonly found between centrals and laterals than between laterals and canines. The GP was more likely to be observed in the BRG, UIG, and CG. The results demonstrated that the GP was not found to be present in the majority of the cases treated with maxillary agenesis, regardless of the method of treatment. The mean W/H ratios of the laterals ranged between 0.75 and 0.90. CONCLUSION   Although the GP may be a useful diagnostic guide, it was not observed in the majority of esthetic outcomes of patients treated with maxillary LI agenesis in this study. CLINICAL SIGNIFICANCE The assessment of the golden proportion and width/height ratio of upper anterior teeth in patients with upper lateral incisor agenesis treated with either implants or tooth re-contouring may assist dentists and patients in deciding the best treatment option based on the peculiarities of each case.