Diffuse sclerosing osteomyelitis and florid osseous dysplasia.

The literature on diffuse sclerosing osteomyelitis of the mandible has included at least two groups of lesions: (1) those from which bacterial infectious agents are rarely isolated (chronic-tendoperiostitis); and (2) those from which bacteria are readily isolated (true diffuse sclerosing osteomyelitis). The latter should be distinguished from secondarily infected florid osseous dysplasia. In this article the features of 16 patients with sclerotic jawbone lesions associated with symptoms of infection are analyzed. Eleven patients showed a large area of sclerosis of the mandible that was not restricted to the alveolar process and was surrounding an infectious focus. The histologic pattern revealed a deposition of reactive bone. These lesions are considered to represent true diffuse sclerosing osteomyelitis. The remaining five patients showed sclerotic lesions restricted to the alveolar process in one or more quadrants of the jaws. Apart from inflammation and reactive changes, histologic pattern revealed a fibroblastic stroma with bone and cementum-like structures that are formed by metaplasia. These lesions are considered to represent secondarily infected florid osseous dysplasia.