OSTEOMYELITIS

 Osteomyelitis may result from the direct extension of pulpal or periodontal infection without the formation of a granuloma or from acute exacerbation of a periapical lesion. It may also occur following penetrating trauma or various surgical procedures. Extension of the infection into adjacent soft tissue and fascial spaces is common, and often the presenting clinical symptoms are swelling, pain and suppuration. Sequelae to transcortical extension of the inflammatory process can include cortical destruction, fistulization and periosteal reaction. These changes can be evaluated by imaging techniques.5

Histopathology. The bone pathology presents various forms, depending on the virulence of the infecting microorganism, the host capacity of effective immune response and the kind of reaction of the periosteal and osseous tissues. Chronic osteomyelitis histopathology depicts irregular fragments of devitalized bone surrounded by dense fibrous tissue heavily infiltrated by plasma cells, lymphocytes, and only a few granulocytes (Figure 5).

Imaging. Appropriate evaluation of radiographic types of osteomyelitis is necessary for treatment planning. Kazunori Yoshiura6 classified mandibular osteomyelitis into four basic patterns, as lytic, sclerotic, mixed and sequestrum patterns. Our case presented with the latter pattern. In some cases computerized tomography or scintography may be necessary.1

Presentation. Patients can have swelling of the face, tenderness and pain (localized), draining sinus tracts, suppuration, tooth loss, possible necrotic bone fragment formation, and a low-grade fever. New bone and oral mucosa will occasionally regenerate beneath the sequestra, probably because of activation of periosteal osteoblasts. According to Reinert,6 clinical examination alone can be enough to diagnose mandibular chronic osteomyelitis, particularly at the onset of the disease. The radiographic characteristics of the osteomyelitis presented were a radiolucent area circumscribing a central bone sequestrum and radiopacity in the surrounding bone. Due to the characteristics of the pathology and the clinical history, there was no need for other exams.

Predisposing factors. Viral fevers (eg, measles), malaria, anemia, malnutrition, and use of tobacco are found to contribute to the development of osteomyelitis.

Management. Treatment goals include reversal of any predisposing conditions, long-term antibiotic therapy. Antibiotic therapy alone is not enough for the treatment of osteomyelitis, since the devitalized osseous tissue in combination with the capsule of the surrounding fibrous connective tissue protects the microorganisms from the drug action. Corticotomy can be used as treatment, and if not effective, bone resection can be done as a more radical alternative. However, aggressive treatment may cause loss of function, exposure of the inferior alveolar nerve and problems regarding the reconstruction.7 High doses of antibiotics should accompany any aggressive surgical treatment. Some authors feel that penicillin G is the medication of choice, followed by clindamycin.7 Since most of the osteomyelitis infections are polymicrobial oral flora (primarily facultative streptococci, Bacteroides spp, Peptostreptococcus,and Peptococcus), antibiotic treatment includes penicillin, metronidazole, and clindamycin. Operative interventions such as sequestrectomy, decortication, removal of nonviable bone (ie, mandibulectomy or maxillectomy), and dental extractions, are also needed. A wide incision to remove all the diseased tissue, as well as primary closure of the surgical wound is performed to ensure a successful operation.