Dislocation of an upper third molar by an ossifying fibroma--case report.

Background: The occurrence of ossifying fibromas (OFs) in childhood and adolescence has been described in the literature, along with different courses of the disease due to different growth rates.
Case Report: In the case of the 15-year-old female patient presented here, an OF resulted in displacement of a maxillary third molar far into the maxillary sinus. It is assumed that the tumour originated coronal to the affected tooth 18. Radiographs document an initial rapid growth of this tumour over a period of 2 years, while its growth almost completely ceased in the next 2 years immediately prior to diagnosis and surgical treatment. The operation was complicated by unexpected profuse bleeding from the tumour tissue.
Conclusion: The peculiarity of the OF in the case presented here is its similarity, in terms of clinical and radiological appearances, with a follicular cyst, its unusual place of origin that resulted in the migration of the tooth 18 into the maxillary sinus, its different growth dynamics, and the pronounced haemorrhage encountered as the tumour was surgically removed.