Bone Diseases
Medication-Related Osteonecrosis of the Jaws
aka MRONJ · BRONJ
Exposed necrotic jaw bone persisting >8 weeks in a patient on antiresorptive or antiangiogenic therapy without prior head-and-neck radiotherapy.
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Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Medication-Related Osteonecrosis of the Jaws figures pending faculty review.
§ overviewOverview
AAOMS 2022: exposed bone or bone probed through a fistula in the maxillofacial region persisting >8 weeks in a patient with current or previous antiresorptive/antiangiogenic drug exposure and no history of jaw radiation or obvious metastatic disease.
§ etiologyEtiology
- 01Bisphosphonates (zoledronate, alendronate, pamidronate)
- 02Denosumab
- 03Antiangiogenics: bevacizumab, sunitinib
- 04mTOR inhibitors
§ riskRisk Factors
- 01IV route, high cumulative dose, oncology indication
- 02Dental extraction, implant, periodontal surgery
- 03Poor oral hygiene, denture trauma
- 04Diabetes, steroids, chemotherapy, smoking
§ pathogenesisPathogenesis
Suppressed osteoclast function → impaired bone remodelling; reduced angiogenesis; oral microbial infection precipitates necrosis after minor trauma.
§ clinicalClinical Features
- 01Exposed necrotic bone
- 02Pain, swelling, halitosis, purulence
- 03Loose teeth, sinus tracts
- 04Mandible > maxilla (posterior)
§ radiographicRadiographic Features
- 01Ill-defined osteolysis with sequestra
- 02Persistent extraction socket
- 03Thickened lamina dura, periosteal reaction
§ investigationsInvestigations
- 01OPG, CBCT for extent
- 02MRI/CT for advanced staging
- 03Cultures for superadded infection
§ classificationClassification
- 01AAOMS staging: Stage 0 (non-exposed), Stage 1 (exposed, asymptomatic), Stage 2 (exposed, symptomatic/infected), Stage 3 (extending beyond alveolus, pathological fracture, extra-oral fistula)
§ treatmentTreatment
- 01Prevention key: dental screening BEFORE therapy; complete extractions with 4–6 wk healing
- 02Stage 0/1: chlorhexidine mouthwash, analgesia, careful monitoring
- 03Stage 2: antibiotics (amoxicillin/metronidazole), superficial debridement
- 04Stage 3: sequestrectomy/resection with reconstruction
- 05Drug holiday controversial — coordinate with oncologist; not evidence-based for denosumab
- 06Adjuncts: PRF, teriparatide (non-oncology), ozone, hyperbaric oxygen (limited evidence)
§ complicationsComplications
- 01Pathological fracture
- 02Oro-antral/oro-cutaneous fistula
- 03Chronic osteomyelitis
- 04Loss of function
§ prognosisPrognosis
Difficult; prevention >> treatment. Stage 3 often requires major resection.
§ examKey Examination Points
- 01Take a bisphosphonate history for EVERY extraction
- 02Educate patients on oral hygiene before starting antiresorptives
§ revisionQuick Revision Summary
- 01AAOMS 2022 · exposed bone >8 wk · prevention with pre-treatment dental clearance
§ vivaBDS Viva Questions
- 01AAOMS diagnostic criteria?
- 02Drug holiday — evidence?
- 03Preventive protocol before IV bisphosphonate?
§ mcqsMCQs — Assessment (3)
Question 1
Duration of exposed bone required for MRONJ diagnosis:
Question 2
Highest-risk drug:
Question 3
Best preventive strategy:
§ evidenceReferences & Evidence
Current Classification
WHO Classification of Tumours Online — Head and Neck
IARC / WHO · 2022
Continuously updated online edition of the WHO head and neck tumour classification.
Evidence summary
Highest level of evidence linked to this page: WHO / Official Classification.
- L1 · Classification — 1
- L2 · Guideline — 1
- L3 · Systematic review — 1
- L6 · Textbook — 3
2 linked sources were published from 2024 onwards. Where guidance is limited or contested, rely on the higher-level sources above rather than this summary. Educational use only — not a substitute for clinical judgement.
Content last reviewed
September 2026
Evidence last reviewed
September 2026
Next scheduled review
September 2027
Review status
EVIDENCE REVIEWED
Search latest PubMed evidence
Last literature search: 7 September 2026
Current Classification
IARC / WHO. IARC · 2022
Continuously updated online edition of the WHO head and neck tumour classification.
Clinical Guidelines
Ruggiero SL, Dodson TB, Aghaloo T et al.. Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons · 2022 · 80(5):920-943
AAOMS position paper defining staging and management of medication-related osteonecrosis of the jaw.
Systematic Reviews & Meta-Analyses
de Almeida-Silva LA, Lupp JDS, Sobral-Silva LA et al.. Oral surgery, oral medicine, oral pathology and oral radiology · 2024 · 138(1):66-78
Systematic review of osteoradionecrosis incidence after intensity-modulated radiotherapy for oral cavity cancer.
Histopathology References
Barnes L. CRC Press · 2008
Detailed histopathological reference for head and neck diagnostic criteria.
Textbook References
Neville BW, Damm DD, Allen CM et al.. Elsevier · 2024
Standard reference textbook of oral and maxillofacial pathology used throughout this atlas.
Rajendran R, Sivapathasundharam B. Elsevier · 2020
Undergraduate and postgraduate oral pathology textbook widely used in BDS and FCPS curricula.
Additional sources cited on this page
- Ruggiero SL et al. AAOMS Position Paper. J Oral Maxillofac Surg 2022
Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.