An accurate radiographic diagnosis is essential to evaluate and predict the possible outcome related to the extraction of impacted third molars. However, the presence or absence of these radiographic signs does not always determine the possibility of injury to the mandibular canal. The present study therefore gave adequate insight to maxillofacial surgeons who need to decide whether CBCT is required in addition to pre-operative intraoral periapical radiography in mandibular third molar extractions.