Exploring the Interplay of the Impaction Type of the Mandibular Third Molar With Second Molar Distal Surface Caries

<b>Introduction:</b> The purpose of this study was to investigate the association of the different types of mandibular third molar impaction with the development of caries on the distal surface of the mandibular second molar. <b>Materials and methods:</b> This prospective descriptive-analytical study was conducted among 67 participants with similar DMFT index scores referred to Zahedan Faculty of Dentistry. Third molars were categorized according to the Winter (angulation) and the Pell and Gregory (ramus relationship and impaction depth) classifications. To examine the association between the study variables, a chi-square test was performed. All statistical analyses were performed at a significance level of 5%. <b>Results:</b> Mesioangular (35.8%), class II (67.2%), and level B (65.6%) were the most common impaction types in mandibular third molars. These impaction types were also significantly associated with the occurrence of caries on the distal surface of the mandibular second molar (<i>p</i> ≤ 0.05). <b>Conclusion:</b> High-risk patients prone to developing distal caries in the mandibular second molar should be identified to formulate a strict screening and follow-up protocol.