What Is Osteoradionecrosis?
Osteoradionecrosis is a serious and difficult-to-treat complication of radiotherapy in which irradiated bone tissue undergoes necrosis as a result of radiation-induced vascular destruction.
The most widely recognised form affects the jaw and often develops following dental procedures in patients who have received radiotherapy to the head and neck region.
However, osteoradionecrosis may affect any irradiated bone, including the ribs, scapula or pelvis, depending on the area exposed to radiation.
Symptoms include persistent pain, swelling, difficulty chewing or moving the affected area, exposure of necrotic bone through the mucosa and, in more severe cases, pathological fractures.
Diagnosis is based on clinical assessment and imaging findings. A high degree of clinical suspicion is always required in patients with a history of radiotherapy.
Pathophysiology and Characteristics of Osteoradionecrosis
The pathophysiology of osteoradionecrosis reflects the general model of radiation-induced tissue injury. Radiation damages the blood vessels supplying the bone, leaving it poorly vascularised, hypoxic and unable to respond adequately to any additional biological demand.
Even a routine dental extraction involving an irradiated jaw may trigger a progressive necrotic process that does not resolve spontaneously.
A characteristic feature is the limited response to antibiotics. Necrotic bone has no functional blood supply, which means that antibiotics cannot reach the affected area in adequate concentrations.
In addition, hypoxia promotes the growth of anaerobic bacteria that may be difficult to eradicate with conventional antibiotic treatment. This combination makes osteoradionecrosis one of the most challenging oncological complications encountered in clinical practice.
Scientific Basis
Osteoradionecrosis is one of the most extensively documented indications for hyperbaric oxygen therapy. Randomised clinical trials, most notably the classic study by Marx, have reported significantly lower rates of healing failure and a reduced need for extensive surgical resection in patients who received hyperbaric oxygen therapy before and after dental procedures involving irradiated tissues.
The documented ability of hyperbaric oxygen therapy to stimulate neovascularisation and enhance osteoblast function within irradiated bone is the principal mechanism underlying its therapeutic role. This evidence has led to its inclusion in clinical protocols for the management of osteoradionecrosis internationally.
The Role of Hyperbaric Oxygen Therapy
In osteoradionecrosis, hyperbaric oxygen therapy may be used in two ways: preventively, in patients with a history of radiotherapy who require dental or other surgical procedures within irradiated areas, and therapeutically, in patients who have already developed osteoradionecrosis.
When used therapeutically, the objective is to restore the viability of irradiated bone by stimulating neovascularisation and reactivating osteoblasts. Increased oxygenation helps restore biological activity within tissue that has become severely compromised, allowing vascularisation to develop gradually and regenerative processes to resume.
A typical protocol may include 30 preoperative sessions followed by 10 postoperative sessions, or 30 to 40 sessions during the therapeutic phase.
Treatment is planned in close collaboration with the oncologist, dentist and surgeon.