Garré's osteomyelitis of the jaw is a unique clinicopathologic entity that is characterized by asymptomatic focal osteomyelitis and exuberant periosteal deposition of bone. Odontodysplasia is a rare developmental anomaly of tooth formation in young children. Its causes remain unknown.
A 9 -year-old boy presented for evaluation of a painless swelling in the right side of the mandible. The swelling was bone hard and nonfluctutant. Intraoral examination showed partial obliteration of the mucobuccal fold by a bony mass, and the erupted lower right second premolar was malformed. Several kinds of X-ray examinations revealed proliferative periostitis with new bone formation. In addition, the lower right second premolar showed a so-called ghost-like appearance radiographically. Biopsy of the periosteal mass was performed, and the histopathologic diagnosis was reactive bone formation of the periosteum.
In this rare case, the periosteal bony reaction in the mandible was successfully treated by tooth extraction with curettage and antibiotic therapy.
Osteomyelitis in our patient might have been caused by dental caries of the deciduous lower right second molar. Odontodysplasia resulted from periapical inflammation of the deciduous lower right second molar subsequent to osteomyelitis with periostitis.
