A 27-year-old male patient presented with a six-month history of swelling involving the left posterior mandible. The patient’s medical history revealed no co-morbidities and the dental history was non-contributory. Extra-orally, there was a localised hard bony swelling involving the left posterior mandible. Intra-oral examination revealed a full complement of teeth with the left maxillary lateral incisor crown appearing malformed and a retained left maxillary deciduous canine. A panoramic radiograph revealed a well-defined, multilocular radiolucency with scalloped inferior borders in the left posterior mandible associated with the fi rst to third molars (Figure 1). On further examination, a periapical was taken and revealed that the left maxillary lateral incisor appeared malformed with a periapical radiolucency (Figure 2). The periapical radiograph confi rmed the presence of a double dens invaginatus on the mesial and distal aspects. The patient was referred for an incisional biopsy of the lesion in the left posterior mandible, which was subsequently diagnosed as an inflamed odontogenic keratocyst and managed accordingly.