Hyperostosis and fixed partial denture pontics: report of 16 patients and review of literature.

A total of 19 hyperostoses underlying mandibular posterior fixed partial dentures were observed in 16 patients. In three patients the lesions were bilateral. Histologic examination of hyperostoses from eight patients showed that they were composed essentially of hyperplastic lamellar bone. Radiographic and clinical evidence suggested that subpontic hyperostoses are chronic, slow growing lesions with an exclusive predilection for the mandibular molar-premolar site. They appear to have variable growth rates and attain widely variable maximum size. The etiology of subpontic hyperostoses is unknown, but it is possible that inflammation, trauma, mandibular and occlusal function, and genetic factors, either individually or in combination, play a role in the initiation and development of these lesions. Subpontic hyperostoses have potential periodontal and restorative implications that may require their surgical removal.