Pattern of Mandibular Third Molar Impaction and Relationship to the Inferior Alveolar Canal: Retrospective Cone Beam Computed Tomography Analysis in a Group of Sri Lankan Patients

Cone beam computed tomography (CBCT) provides a precise three dimensional analysis of vicinity of Impacted Mandibular third molar (IMTM) which helps in surgical decision making. Objective: Objective of this study was to analyze the pattern of IMTM and the relationship of inferior alveolar canal to the tooth in 68 patients presented in year 2014 University Dental Hospital, Sri Lanka. Methods: The study sample included 112 IMTM teeth in 68 patients (54.5 % females, 45.5 % males) with average age of 28 years. Preoperative radiological assessment of IMTM was carried out with the aim of analyzing relationship of inferior alveolar canal to the roots of IMTM, analyzing their morphology, predicting anticipated difficulty in exodontia of IMTM and complications such as damaging the inferior alveolar nerve Results: Pell and Gregory Class I B pattern of impaction was predominant in the sample with mesioangular impaction being the most commonly occurring angulation of impaction. The Inferior alveolar canal was placed on buccal aspect of root apex in 35.7% of cases whereas in 33.9% of cases it was lingually placed. Conclusion: In conclusion the Pattern of impaction and the morphology of IMTM in current study comply with international norms except in few aspects.