Osteomyelitis of the Jaw

Osteomyelitis of the jaw is infection of the cortical and medullary bone of the mandible or maxilla. It is most often odontogenic, arising from a periapical or periodontal source or a mandibular third molar, and it is far commoner in the mandible because of its poorer blood supply.

It is described as acute suppurative or chronic suppurative, with sclerosing and proliferative forms treated as separate entities. Systemic risk factors are diabetes, immunosuppression, HIV, alcohol misuse, malnutrition, sickle cell disease, smoking and previous radiotherapy.

Pathophysiology. Mixed oral flora, mainly streptococci, Prevotella, Fusobacterium and Peptostreptococcus, enter the marrow and cause inflammation and raised pressure that compresses the inferior alveolar vessels.

Ischaemia leads to bone necrosis and sequestrum formation, with pus tracking through the cortex into soft tissue. Staphylococcus aureus, Salmonella (in sickle cell disease), Actinomyces, Mycobacterium tuberculosis and fungi are other causes.

Deep, boring pain, swelling, fever, malaise, tender and loose teeth, trismus, foul discharge and sinus tracts. Numbness of the lower lip (Vincent sign) from inferior alveolar nerve involvement is a late feature. Chronic disease shows recurrent pain and swelling, draining sinuses, exposed bone and sequestra.

Ask about dental infection, extractions, trauma, fractures, drugs (steroids, antiresorptive therapy) and radiotherapy.

Pathological fracture, spread to the neck or skull base, sepsis, and airway threat need emergency admission.

• Bloods: full blood count, ESR, C-reactive protein, glucose or HbA1c, and blood cultures when febrile. HIV testing when no obvious cause is found.
• Panoramic radiograph: normal in the first 1 to 2 weeks, since 30 to 60% of bone mineral must be lost to show, then moth eaten radiolucency, sequestra and periosteal reaction.
• CT for bone destruction, sequestra and cortical breach. MRI for marrow oedema in early disease and soft tissue spread. Bone scintigraphy where available.
• Bone biopsy and culture, aerobic, anaerobic, and mycobacterial and fungal when immunosuppressed or failing treatment. Swabs of sinus tracts are unreliable.
• Biopsy to exclude malignancy, lymphoma and metastasis in non-healing disease.

Differential diagnosis.

• Osteoradionecrosis and medication related osteonecrosis of the jaw
• Chronic sclerosing and diffuse sclerosing osteomyelitis
• Garré proliferative periostitis
• Malignancy (osteosarcoma, Ewing sarcoma, lymphoma, metastasis)
• Fibro osseous lesions and Paget disease
• Langerhans cell histiocytosis
• Actinomycosis and tuberculosis

• Remove the source: extract or treat the infected tooth, drain collections, and debride necrotic bone.
• Antibiotics after bone culture where possible. Empirical choice: benzylpenicillin 1.2 g intravenously every 6 hours (up to 2.4 g in severe disease) with metronidazole 500 mg intravenously every 8 hours. Penicillin allergy: clindamycin 600 mg intravenously every 6 to 8 hours (maximum 2.4 g daily), with attention to Clostridioides difficile. Directed later by culture.
• Step down to oral amoxicillin 500 mg to 1 g three times daily with metronidazole 400 mg three times daily, or clindamycin 300 to 450 mg four times daily, once the patient is afebrile and improving. Total duration is usually 4 to 6 weeks for acute disease and 6 weeks to several months for chronic disease. Reduce amoxicillin to 500 mg every 12 hours at eGFR 10 to 30.
• Surgery: sequestrectomy, saucerisation or decortication, and resection with reconstruction for extensive, refractory disease or pathological fracture. Stabilise fractures by fixation.
• Hyperbaric oxygen is an adjunct in refractory cases, with limited evidence.
• Control diabetes, stop smoking and alcohol, and improve nutrition.
• Analgesia: paracetamol 1 g every 6 hours (maximum 4 g daily) with ibuprofen 400 mg every 8 hours with food when renal function allows.

Special groups. Sickle cell disease needs coverage for Salmonella (ceftriaxone 2 g intravenously daily) and haematology input. Children are dosed by weight.

Monitoring. C-reactive protein and ESR weekly during treatment, and imaging at 6 to 12 weeks and as needed. Review for recurrence for at least 12 months.

Referral and escalation. Refer to oral and maxillofacial surgery and infectious diseases. Urgent referral for fracture, sepsis, spreading infection, neurological signs or suspected malignancy.