A 12-year-old female was referred to the Department of Oral and Maxillofacial Surgery due to delayed eruption of the permanent lower incisors and permanent right-sided canine detected during orthodontic treatment. He also reported occasional pain and gingival swelling. Personal history included focal epilepsy and no allergies. On examination there was an absence of the lower right incisors and canine and a slight bulging of the vestibular cortex of the mandible at this location. Radiographic tests included an orthopantomography and a periapical radiograph, where an intraosseous cystic lesion was observed, measuring 20 x 30 millimetres and showing well-defined margins with some radiolucent and radiopaque images inside. In addition, some radiopaque structures resembling a tooth could be identified inside the cyst together with a lateral displacement of the roots of the neighbouring teeth without apical resorption. With the diagnosis of suspected mandibular compound odontoma, the patient underwent surgery under local anaesthesia, although the cyst could not be completely removed due to lack of cooperation from the patient. Therefore, a second surgery was performed under general anaesthesia in the Major Outpatient Surgery unit, performing a complete removal of the tumour followed by curettage of the surgical site.
Histological analysis revealed a composite odontoma with areas of proliferative ameloblastic cells. Microscopically, a nested and banded proliferation of odontogenic palisaded epithelium together with stellate cells located in the centre of the nests could be observed. The stroma surrounding the epithelial nests showed areas of fibromyxoid tissue and areas of collagen with abundant cementum deposits surrounded by ameloblasts and scattered remnants of tooth enamel.
Therefore, regular check-ups by clinical examination and CT scans were performed without evidence of recurrence after 24 months of evolution.
