An 11-year-old girl was referred to our clinic for the assessment of a radiopaque lesion in the left maxillary molar region. We clinically diagnosed this lesion as a compound odontoma, and surgical removal was performed with extraction of the left upper first molar. Histopathological examination of the removed specimen, which measured 40 × 35 × 30 mm, also confirmed the diagnosis of a compound odontoma. There was no evidence of recurrence or complications after surgery. Odontomas tend to be less than 30 mm in diameter. As for previous articles from Japanese institutions, only two cases of compound odontoma more than 30 mm in diameter that arose in the maxillary molar region have been reported. We think that the present case is the largest reported case of compound odontoma occurring in the maxillary region in Japan. We therefore report a summary of this case and review the literature on odontomas in the maxillary molar region that were more than 30 mm in diameter and reported during the past 53 years from 1960 through 2013.
