Aim: The aim of this cross sectional study was to assess the prevalence and pattern of impacted mandibular third molars on digital panoramic radiographs.

Methods: In the study we reviewed 745 digital panoramic radiographs of patients treated in our institution from 2017 June to 2018 June. The radiographs were retrieved from the archives of Department of Radiology and were evaluated for the prevalence of impacted mandibular third molars, their pattern of distribution and associated pathological conditions. The study also evaluated presence of other impacted teeth as well as partially impacted mandibular third molars.

Results: From the total of 745 radiographs reviewed, a total of 293 impacted teeth were observed. Mandibular third molars (198) were the most commonly encountered impactions, followed by maxillary third molars (69), maxillary canines (11) and supernumerary teeth (15). 135 subjects (18.1%) presented with at least one impacted mandibular third molar. 105 (14.1%) subjects presented with impacted mandibular left third molar and 93(12.5%) presented with impacted mandibular right molar, 22 (3%) and 21(2.8%) subjects presented with partially impacted mandibular right and left molars respectively. The analysis of the pattern of the impacted mandibular teeth showed that majority were in the mesioangular (47%) position, followed by horizontal (32.32%), vertical (15.15%) and distoangular (5.56%) positions.

Conclusion: The study revealed that 18% cases showed impacted mandibular third molar, with mesioangular (47%) pattern was more frequent.

Keywords: Impacted mandibular third molar, Impaction, Mesioangular, Molar, Kerala.

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Shamji Shajahan

Mar Baselios Dental College, Kothamangalam, Kerala, India