A review of the patient’s past medical history was significant for osteoporosis and arthritis. She had been treated for osteoporosis with alendronate (Fosamax) at a dosage of 70 mg per week for three years.
Upon examination, the right posterior mandibular alveolar ridge appeared to be covered by intact mucosa (Figure 1). On closer inspection, however, a small ulcer with an adjacent small fistula was discovered hidden beneath the mucosal fold covering the superficial part of the right posterior alveolar ridge close to the retromolar pad area (not apparent in this photograph).
Figure 1. Irregular swelling on the right mandibular alveolar ridge. The alveolar mucosa appears intact but a small sinus is present below the fold in the posterior mandible. (Not visible in the photograph.)
The skin overlying the jaw, however, showed a large cutaneous fistula (Figure 2) which intermittently drained exudate for a period of six months.
Figure 2. The skin overlying the jaw with a large cutaneous fistula, which was reported to intermittently drain exudate.
Panoramic and CT-scan radiographs were performed. The panoramic radiograph revealed large pieces of bony sequestra in the right posterior mandible surrounded by an irregular radiolucency and what appeared to be a pathologic fracture (Figure 3).
Figure 3. A portion of a panoramic radiograph demonstrating a large and ill-defined mixed radiolucent and radiopaque lesion in the right posterior mandible with a pathologic fracture and large bony sequestration.
The latter was confirmed with a CT-scan sagittal image (Figure 4). The CT scan also clearly demonstrated a large bony sequestrum undergoing resorption surrounded by the irregular radiolucency. Both radiographs showed evidence of sclerotic bone surrounding the lesion.
Figure 4. A CT-scan (sagittal view) of the right posterior mandible demonstrating a large and irregular bony sequestrum, pathologic fracture, and sclerosis of the bone surrounding the lesion.
Incisional Biopsy Findings
Under local anesthesia the biopsy specimens were obtained using simple local curettage of the area (Figures 5 and 6). Histologic examination of the curetted material revealed multiple pieces of decalcified hard and soft tissue. The latter was made up of granulation tissue covered by stratified squamous epithelium (Figure 5) and infiltrated by many neutrophils, lymphocytes, and plasma cells. The bony fragments comprised a significant portion of the specimen (Figure 6) and were mostly lamellar in type with Haversian systems devoid of viable osteocytes. The bony fragments showed evidence of external resorption covered by bacterial colonies of mixed oral flora.
Figure 5. Low power (x100) histology illustrating the soft tissue component made up of heavily inflamed granulation tissue covered by epithelium.
Figure 6. Higher power (x200) histology illustrating bony trabeculae devoid of viable osteocytes. The bone shows evidence of resorption surrounded by bacterial colonies.