An Anterior Tooth Size Comparison in Unilateral and Bilateral Congenitally Absent Maxillary Lateral Incisors

The purpose of this study is to compare the anterior tooth size width in patients with congenitally missing maxillary lateral incisors using the Bolton Index and divine proportion. The study sample consisted of thirty pairs of orthodontic models with unilateral (twelve patients; 7 females, 5 males) and bilateral (eighteen patients; 13 females, 5 males) absence of maxillary lateral incisors. The mean ages of the selected cases were 17.7 and 17.5 years, respectively. Descriptive statistics were used for the data analysis. The result showed the mean of the Bolton Index in cases with bilateral absence was closer to the Bolton mean than in cases with unilateral absence. In the unilateral absence cases the width of the existing lateral incisor (5.5 mm) was an average of 1.00 mm less compared to the standard mean (6.5 mm). The divine proportion showed the maxillary central incisors were small in width as indicated by the adjusted value or they were slightly larger in width than the mandibular central incisors. In cases with unilateral and bilateral absence the Bolton Index exhibited maxillary insufficiency, which was confirmed by evaluating the divine proportion of the maxillary and mandibular incisors. The result of the present study will be of great help to both the orthodontist, whether to open or close the space, and to the prosthodontist to restore the missing teeth of patients having missing maxillary lateral incisors.