Patterns of Mandibular Third Molar Impactions and Its Association with Carious Lesions and Periodontal Defects: A Retrospective Cross-Sectional Study

Shahad B Alsharif,1 Majd B Alsharif2 1Department of Periodontology, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaCorrespondence: Shahad B Alsharif, Department of Periodontology, Faculty of Dentistry, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia, Email [email protected]: Clinical consensus on prophylactic extraction of impacted mandibular third molars is still debated. This study aims to explore the impaction patterns of mandibular third molars and their associated effects on the adjacent second molars within a Saudi population, thereby providing some clinical insights for prophylactic extraction.Methods: This retrospective cross-sectional study evaluated 1700 orthopantomograms of Saudi patients, obtained from the dental hospital database at King Abdulaziz University, Jeddah, Saudi Arabia, from August 2024 to June 2025, with convenience sampling. Mandibular third molar impaction patterns were assessed according to Winter’s classification, along with their association with pathological conditions, including carious lesions and periodontal defects affecting the adjacent mandibular second molars.Results: 681 impacted mandibular third molars were identified and analyzed. The prevalence of these impactions was higher in females (54.2%) than in males (45.8%) (p < 0.05). Mesioangular impaction pattern was the most frequently detected, followed by horizontal. A significant association was observed between gender and the impaction patterns (p < 0.001), with the inverted and buccolingual impaction patterns predominantly observed in males, accounting for 100% and 90.0% of the impactions, respectively. The prevalence of carious lesions and periodontal defects was 23.9% and 66.9%, respectively. The two most frequent impaction patterns, horizontal and mesioangular, were significantly associated with these pathological conditions (p < 0.001).Conclusion: Prophylactic extraction of impacted mandibular third molars, particularly those exhibiting mesioangular and horizontal impaction patterns, should be considered to prevent the deleterious consequences of their retention. However, this recommendation is specific to the population inspected. Further studies focusing on diverse populations are encouraged to acquire evidence-based, population-specific recommendations to support broader clinical applicability.Keywords: impacted tooth, third molar, periodontal disease, dental caries, mandible, panoramic radiography