Pathologies Associated with Second Mandibular Molar Due to Various Types of Impacted Third Molar: A Comparative Clinical Study.

Introduction: Impacted third molars are associated with various degrees of damage to the second molars. The possible complications also include distal cervical caries, root resorption of second molar, periodontal problems, odontogenic cysts, etc. Whether a particular impacted third molar is going to affect second molar depends upon its position and orientation in the bone. Materials and Method: This study was carried out in 418 cases. Three examiners evaluated the patient clinically and radiographically and only those cases were included in this study where at least two observers agreed. A total of 341 cases (163 males and 178 female), age range (15-40 years) with impacted mandibular third molars, were included. Clinically and radiographically, the impacted mandibular third and second molars were evaluated; simultaneously, the prevalence of various pathologies associated with mandibular second molar (dental caries, periodontal pockets, root resorption) due to impacted third molar was also evaluated and compared among various types and positions of impactions. Results: Statistical analysis was carried out using Pearson Chi-square and Asymp. Sig. (two-sided) test. Prevalence of mesioangular impactions was maximum (50.1%). Mesioangular impaction and position B (Pell and Gregory classification) were significantly associated with dental caries (32.20% and 33.90%, respectively), and periodontal pockets were seen higher with position B impactions (26.8%) {horizontal (14.7%), disto-angular (12.10%), vertical (14.5%) mesioangular (16.4%%)} in adjacent mandibular second molar. Root resorption was seen maximally in horizontal impaction (17.30%) with position c type (12.30%). The order of pathologies associated with second molar due to impacted third molar was dental caries (19.9%) > periodontal pockets (15.2%) > root resorption (8.5%). Discussion: Evidence regarding pathologies are associated with second molar due to impacted third molar aids in decision making for surgical removal of third molars. Different types of impaction and the prevalence of pathologies related to them would aid in treatment planning of the impacted tooth as certain types have high probability of pathologies associated.