J. Bras

Osteoradionecrosis of the mandible: Pathogenesis

Although the precise pathogenic mechanisms are not fully understood, osteoradionecrosis of the mandible is caused by radiation-induced cellular injury, ultimately resulting in a chronic, nonhealing wound. This etiology does not explain the strong predisposition of the mandible to radionecrosis relative to the maxilla, and overlooks the contribution of ischemic necrosis due to radiation-induced disturbances in circulation. In this study, irradiated mandibles with and without osteoradionecrosis and nonirradiated mandibles were examined histologically. Our findings show that osteoradionecrosis of the mandible is an ischemic necrosis due to radiation-induced obliteration of the inferior alveolar artery, while revascularization by branches of the facial artery is disturbed by radiation-induced vascular disease and periosteal damage. The most vulnerable part of the mandible is the buccal cortex of the premolar, molar, and retromolar regions.

Radiographic interpretation of the mandibular angular cortex: A diagnostic tool in metabolic bone loss

Panoramic radiographs of patients with chronic renal failure showed a loss of cortical bone at the mandibular angle; the loss of cortical bone correlated very well with the degree of renal osteodystrophy, established by biopsy of the undecalcified iliac crest. The value of using the cortical thickness at the mandibular angle as a parameter in diagnosing metabolic bone loss is discussed.

Radiographic interpretation of the mandibular angular cortex: A diagnostic tool in metabolic bone loss: Part I. Normal state

Abstract The thickness of the mandibular angular cortex at gonion was measured on panoramic radiographs of 180 normal persons. Before the fifteenth year a distinct cortical layer is missing. After the fifteenth year, the thickness of the mandibular angular cortex is relatively constant except in postmenopausal women of 60 years and older, where the cortical thickness is distinctly thinner.

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.

Mandibular atrophy and metabolic bone loss: a radiologic analysis of 126 edentulous patients

Radiological studies were performed on edentulous patients with and without atrophy of the mandible. Radiological, histomorphometrical and endocrinological studies were performed in edentulous patients with a severe atrophy of the mandible treated by ridge augmentation. The results of these studies showed that metabolic bone loss, histologically and endocrinologically characterized as a secondary hyperfunction of the parathyroid glands, is a causal factor in the pathogenesis of mandibular atrophy.

Diffuse sclerosing osteomyelitis of the mandible: a new concept of its etiology.

Diffuse sclerosing osteomyelitis of the mandible is a disease of unknown etiology. The clinical and radiographic findings suggest an infectious origin, but bacteriologic and histologic findings do not support this concept. Analysis of clinical symptoms, localization of the condition, and posttreatment findings in a group of 27 patients suggest a chronic tendoperiostitis due to muscular overuse as an etiologic factor in diffuse sclerosing osteomyelitis of the mandible. This hypothesis was supported by the initial results of muscle relaxation treatment in 13 of these patients.

Oral manifestations of non-Hodgkin's lymphoma in HIV-infected patients.

The incidence of non-Hodgkins lymphomas (NHL) in patients infected with human immunodeficiency virus (HIV) is relatively high. However, there have been few reports on the clinical and histopathological features of oral manifestations of NHL in these patients. The lesions reported so far were all tumorous swellings with or without ulceration, as in non-HIV-infected patients. In this report 3 cases are presented of HIV-infected patients with solitary, primary oral NHL. These lesions showed a striking resemblance to acute, necrotizing gingivitis, a common finding in these patients, thus making the diagnosis more difficult.

Mandibular atrophy and metabolic bone loss: Endocrinology, radiology and histomorphometry

In 11 edentulous patients with a severe atrophy of the mandible and submitted for ridge augmentation, endocrinological, radiological and histomorphometrical studies were carried out. The results showed that metabolic bone loss, histologically in nearly all patients characterized as a disturbance in mineralization and endocrinologically in 55-73% of the patients as a secondary hyperfunction of the parathyroid glands, plays a rôle in the etiology of mandibular atrophy.

Juxtacortical osteogenic sarcoma of the jaws: Review of the literature and report of a case

The juxtacortical osteogenic sarcoma is a rate tumor, especially in the jaws. Until now, only six cases have been reported. Before describing an additional case in the mandible, it was deemed appropriate to review the literature on juxtacortical osteogenic sarcoma in extracraniofacial locations as well. The data on juxtacortical osteogenic sarcomas of the long bones and those of the jaws are discussed.

Diffuse sclerosing osteomyelitis (chronic tendoperiostitis) of the mandible : An 11-year follow-up report

Diffuse sclerosing osteomyelitis of the mandible is a disease that is characterized by a protracted course of recurrent pain, swelling of the cheek, and trismus. The cause of the lesion has been obscure for a long period of time. Recent research, however, pointed out that this disease is likely to be caused by overuse of the jaw musculature (chronic tendoperiostitis) and can be treated accordingly. The protracted course of the disease and the difficulty of treatment with an eventual positive outcome are illustrated by a case report of a 65-year-old man with an 11-year history of diffuse sclerosing osteomyelitis (chronic tendoperiostitis) of the mandible.