Migration is a kind of eruption abnormality where a tooth grows far from its original site of development. Anomalies in dental eruptions are referred to as ectopia, which might be encountered in several regions around the oral cavity. The incidence of mandibular second premolar impaction has been estimated to be 2.1-2.7%. The frequency of its intraosseous distal migration is 0.25%. We report a case of extremely distally intraosseous migration of mandibular second premolar, which was found in a routine radiography. A 28-year-old woman who attended a dental clinic to treat teeth caries was noticed to have her lower second premolar located horizontally in the homolateral mandibular angle below the inferior alveolar nerve canal on a panoramic view. As the patient was asymptomatic, she was advised to take follow-up radiographs to rule out any cystic/neoplastic changes. Taking a panoramic radiograph in patients with missing mandibular premolars should be considered, because in rare cases migration or transmigration of these teeth may happen.
Keywords: mandible; migration; second premolar.