greater is the opportunity of impeding the progress of the infection. Even before purulent material can be obtained for culture, it is advisable to begin administering an antibiotic in high doses. Of course this may make it difficult to obtain a culture when suppuration begins, but time is the important factor, and the earlier antibiotic therapy can be started, the better is the chance of therapeutic control. As soon as it is possible to obtain a culture, "the antibiotic that the laboratory finds to be most efficacious may be given.
Edema and induration should be observed closely for the first indication of fluctuance so that at the earliest possible moment a liberal incision can be made down to the bony surface for the early evacuation of pus, thereby preventing the pus from elevating the periosteum. If induration extends beyond the limit of the incision after the primary drainage, the incision should immediately be extended.
The destructiveness of osteomyelitis is caused by the pressure and lysis of suppurative material in a confined space. A staphylococcus is usually the cause. If the bacteria are killed or the antibiotic stops their growth, resolution of the infection occurs without the need for surgery beyond the extraction of the offending tooth (if the infection is odontogenic in origin). If the bacteria are resistant to antibiotics (for example, a "hospital staphylococcus") or if a massive collection of pus has formed before effective antibiotic therapy can be instituted, then portions of the bone become devitalized because their blood supply has been cut off by thrombosis of the vessels. The island of dead bone thus formed becomes a convenient place for precipitation of the ionized calcium that has been mobilized by the surrounding osteolytic process and therefore this sequestrum appears as a radiopaque shadow on the radiograph. Nature tends to expel the sequestrum, although occasionally a small sequestrum is lysed during long, effective antibiotic therapy.
The pattern for treatment, then, is (l) effective antibiotic therapy, (2) drainage of purulent material if and when pus forms in spite of antibiotic therapy, (3) a period of supportive therapy during which the drainage area is kept open by dressings and the antibiotic therapy is continued, and (4) sequestrectomy.
The sequestrum should not be removed too early. It should be clearly outlined on the radiograph. If the infection has been controlled, the sequestrum is lifted gently out of its soft tissue bed, or involucrum. This bed is not curetted. Occasionally the overhanging margins of cortical bone are ronguered back to cortical bone that rests on intact medullary bone. This is called saucerization.
The treatment pattern can be interrupted at any of the four stages if normal healing occurs. The antibiotic should be continued for a minimum of 4 to 6 weeks after drainage has ceased. If clinical and radiographic evidence of rampant invasion of the medullary structure of the bone is found and the infectious process has not perforated the cortical plate, holes may be drilled through the inferior border of the mandible to permit drainage of the cancellous structure.
This latter procedure is controversial and depends on the judgment and discretion of the surgeon, who will have to evaluate the
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