Clinical findings, epidemiology, etiology, and pathophysiology
- Area of exposed bone that does not heal
- Numbness or paresthesias within the mouth or jaw
- Pain
- Swelling
- Non-healing sore or ulcer in the mouth
- Incidence of osteoradionecrosis estimated at around 2%
- Improvement in radiation therapy has decreased the incidence
- Radiation therapy causes DNA damage and cell death
- Tumor cells are more susceptible to radiation damage
- Excessive radiation doses can cause normal cells to be overwhelmed by DNA damage
- ORN is the result of cumulative tissue damage caused by radiation
- Radiation creates disturbances in cell metabolism and homeostasis
- Hypovascular environment due to injury to endothelial cells
- Decreased oxygen delivery leads to hypoxic tissues
- ORN is essentially hypocellular-hypovascular-hypoxic tissues

Risk factors, prevention, and treatment
- Size and location of tumor
- Dose and delivery of radiation
- Smoking
- Diabetes mellitus
- Presence of dental disease
- Prevention strategies aim to avoid excess doses of radiation
- Maintaining excellent dental hygiene can help prevent ORN
- Treatments vary depending on disease severity
- Medical treatment with antibiotics
- Hyperbaric oxygen therapy (HBO) or surgical debridement/reconstruction can be used as treatments

Staging and prevention
- Staging system provides baseline reference for management after diagnosis
- No universally accepted prevention and management
- Many proposed preventive approaches lack high quality evidence
- Lack of evidence to determine most effective approach
- Uncertainty for clinicians and patients in choosing treatment
- Dental assessment recommended before radiotherapy
- Strict preventive regime paired with IMRT can prevent ORN
- Dental extractions are a major risk factor but not recommended as treatment
- Frequency of ORN similar in pre- and post-radiotherapy extractions
- Teeth extraction should consider prognosis, oral care, and patient's wishes
- Tooth brushing technique and habit should be high standard
- Chlorhexidine mouthwash and fluoride regime encouraged
- Tailored oral care for trismus and altered taste
- High level of motivation and regular dental appointments important
- Denture adjustments to avoid ORN secondary to trauma

Management options
- Antiseptic mouthwashes and analgesics for acute ORN
- Tetracyclines and penicillin antibiotics to eliminate infection
- Ultrasound therapy improves blood circulation and induces healing
- Hyperbaric oxygen therapy (HBO) recommended by some studies
- Conservative approaches to manage ORN
- Hyperbaric Oxygen Therapy (HBO)
- First described in 1973 as an adjunctive treatment for ORN
- Increases tissue oxygen tension
- Improves collagen synthesis, angiogenesis, and epithelialization
- Controversial use as the only method for ORN management
- Little evidence of clinical benefit and questionable therapeutical significance
- Surgical Management
- Multidisciplinary approach combining HBO therapy and surgery
- Improves local blood circulation
- Resection of necrotic bone and reconstruction with a free flap
- Some studies question the benefit of HBO therapy
- Microvascular reconstruction without HBO therapy is successful
- Pharmacological Methods
- Pentoxifylline enhances blood flow and reduces cytokine cascade
- Tocopherols (vitamin E) inhibit platelet aggregation and scavenge reactive oxygen species
- Clodronate inhibits bone resorption and increases bone formation
- Pharmacological methods target etiologic factors of ORN
- Pentoxifylline not meant for long-term treatment of ORN
- Surgical Procedures
- Removal of small sequestra
- Sequestrectomy
- Alveolectomy with primary closure
- Closure of orocutaneous fistula
- Large resections for advanced disease or failed conservative measures

References (not included in the content grouping)

Osteoradionecrosis (Wikipedia)

Osteoradionecrosis (ORN) is a serious complication of radiation therapy in cancer treatment where radiated bone becomes necrotic and exposed. ORN occurs most commonly in the mouth during the treatment of head and neck cancer, and can arise over 5 years after radiation. Common signs and symptoms include pain, difficulty chewing, trismus, mouth-to-skin fistulas and non-healing ulcers.

The pathophysiology of ORN is fairly complex and involves drastic changes to bone tissue as a result of DNA damage and cell death caused by radiation treatment. Radiation therapy targeting tumor cells can affect normal cells as well, which can result in the death of bone tissue. Advances in radiation therapy have decreased the incidence of ORN, estimated at around 2%. Certain risk factors including the size and location of tumor, history of smoking or diabetes, and presence of dental disease can affect the chances of developing ORN.

Osteoradionecrosis is difficult to prevent and treat. Current prevention strategies are aimed at avoiding excess doses of radiation as well as maintaining excellent dental hygiene. Treatments are variable depending on the provider and disease severity, and can range from medical treatment with antibiotics to hyperbaric oxygen therapy (HBO) to surgical debridement or reconstruction.