Incidence and Pattern of Impacted Lower Third Molars Using Cone Beam Computed Tomography (CBCT): A Retrospective Study

Abstract

Background: Impacted mandibular third molars are among the most common dental problems, with varying prevalence in different populations. This retrospective study assessed the incidence and pattern of impacted lower third molars using cone-beam computed tomography (CBCT) in relation to angulation, laterality, and demographic data. Materials and Methods: A retrospective study was performed by analyzing the CBCT images of patients who attended the Empire Dental Polyclinic in Sulaimani, Kurdistan Region, Iraq, between January 2022 and December 2024. Mandibular third molars were included if they were impacted, bordered peripherally, or completely by the mandible on at least one image. The affected teeth were coded using the angulation system developed by Winter (vertical, mesioangular, distoangular, and horizontal angulations). Results: In the sample, 36.2% of the patients had mandibular third-molar impaction. Bilateral impaction (19.7%) was more common than unilateral impaction (16.5%). The most common pattern was mesioangular impaction (46.8%), followed by vertical (25.2%), horizontal (18.7%), and distoangular (9.4%) patterns. The highest prevalence of impaction was found in the age group of 20–29 years, and it decreased with increasing age. The study population was 57.8% female, and they had a higher impaction rate than their male counterparts. Conclusion: This study found a moderate prevalence of mandibular third molar impaction in a young Iraqi population, with bilateral involvement and mesioangular angulation as the dominant patterns of impaction. These findings support early radiographic assessment in young adults and highlight the need for population-specific data to guide clinical practice.