Prevalence and pattern of congenitally missing of maxillary lateral incisors and mandibular second premolars in a sample of dental patients in North of Iran

Introduction: Congenital missing of maxillary lateral incisors and mandibular second premolars are one of the most common developmental dental anomalies that can affect patient’s function and aesthetics. The aim of this study was to determine the prevalence and pattern of congenital missing of lateral maxillary teeth and second mandibular premolars in patients referred to the Dental Faculty of Guilan University of Medical Sciences in a 5-year period. Material & Methods: In this study, 1054 panoramic radiographs from 9-to-14- year-old patients (476 males and 578 females) were evaluated for the congenital missing of lateral maxillary incisors and mandibular second premolars. The data collected were analyzed using Kruskal Wallis, Mann- Whitney, Fisher Exact and Chi-square tests. Results: Among 1054 panoramic radiographs, 75 cases indicated missing of maxillary lateral incisor and mandibular second premolar (7.1%). The prevalence of congenital missing of second mandibular premolar was higher in females compared to males, and this difference was statistically significant (P = 0.012), however the missing of upper lateral incisors did not show the same sex tendencies (P=0.294). There was no significant relationship between the distribution of congenital missing of maxillary lateral incisors and mandibular second premolars with the incidence side (P=0.330, P=0.197 respectively), also no significant difference was detected between the unilateral or bilateral occurrence of missing (P=0.689, P=0.617). Conclusion: since the lack of teeth causes serious problems in aesthetic and function, frequent examination of children for early detection seems necessary.