Pattern of impacted mandibular third molars in Calabar, Nigeria

Background: The study examines the pattern of impacted lower third molars in Calabar, Southern Nigeria. Patients and Methods: A retrospective analysis of the medical record of all patients, who were treated for symptomatic impacted lower third molar at the Dental and Maxillofacial Surgery Clinic of our institution over a 3-year period was undertaken. Information obtained included patients' demographics, location, type of impaction, presence of caries in the second molar, and indication for extraction. Results: A total of 2,156 patients were seen at the Dental and Maxillofacial Surgery Clinic over the 3-year period of study and of these patients, 118 impacted mandibular third molars were surgically extracted in 97 patients and thus giving a prevalence of 4.7%. The patients' ages ranged 18-48 years, the mean (SD) age was 27.5 (5.60) years. Impaction of the lower third molar occurred equally in both gender with an approximate ratio of 1:1. Mesioangular impaction was the most common type (N = 53; 44.9%), followed by horizontal impaction (N = 34; 28.8%). About half of the impacted teeth were located on the left side (N = 51; 43.2%). There was bilateral location in 21 (17.8%) cases. Recurrent pericoronitis (N= 65; 55.1%) and apical periodontitis (N= 41; 34.7%) were the most common indications for extraction. Conclusion: The prevalence of impacted mandibular third molar in Calabar is lower than previous reports from other urban cities in Nigeria. Mesioangular impaction was the most common impaction type, but unlike previous reports, horizontal impactions constitute a great proportion of third molar impactions seen in this environment.