What Is Osteonecrosis of the Jaw?
Osteonecrosis of the jaw is a serious and difficult-to-reverse condition in which part of the jawbone dies because of an inadequate blood supply.
It occurs in two principal clinical forms: medication-related osteonecrosis of the jaw (MRONJ), which develops mainly in patients receiving bisphosphonates, denosumab or other antiresorptive agents, and osteoradionecrosis, which affects irradiated jawbone and is discussed in greater detail in Section 4.9.4.
Clinically, it presents as exposed necrotic bone within the mouth, usually following tooth extraction or another dental procedure, which remains uncovered by oral mucosa beyond the expected healing period. It may be accompanied by pain, unpleasant odour, difficulty chewing and, in advanced cases, pathological fractures or extraoral sinus tracts.
Characteristics of Osteonecrosis of the Jaw
The pathophysiological mechanism of MRONJ is associated with the suppression of bone remodelling caused by antiresorptive medication. By inhibiting osteoclast activity, these agents interfere with normal bone renewal and create conditions of local vascular insufficiency.
The jaw is particularly vulnerable because of its direct exposure to the oral microbiome and the continuous mechanical stress generated by chewing.
A defining feature is the inability of the mucosa to heal over the necrotic bone. The mucosal tissue cannot migrate across and cover a surface without an adequate blood supply.
This biological limitation is the central target of treatment, and restoring vascular supply represents the principal biological approach to supporting healing.
Hyperbaric Oxygen Therapy in Osteonecrosis of the Jaw and Supporting Studies
The use of hyperbaric oxygen therapy in osteonecrosis of the jaw, including both medication-related and radiation-induced forms, is supported by a growing body of clinical evidence.
Studies involving patients with MRONJ have reported improved mucosal healing, reduction of necrotic bone and clinical stabilization in a proportion of patients who received hyperbaric oxygen therapy alongside surgical and pharmacological management.
Osteoblast activation through increased oxygenation, stimulation of neovascularisation and improved white blood cell function are the documented mechanisms that may explain the clinical benefit. Their common objective is to restore the biological viability of the affected bone.
The Role of Hyperbaric Oxygen Therapy
In osteonecrosis of the jaw, hyperbaric oxygen therapy is used as an adjunctive intervention in collaboration with the oral and maxillofacial surgeon. It does not replace surgical debridement but improves the biological conditions required for successful healing.
Hyperbaric oxygen therapy helps restore activity within tissue compromised by vascular insufficiency. It activates osteoblasts to support bone regeneration, stimulates neovascularisation to improve blood supply and provides mucosal cells with the metabolic support required to migrate and cover the exposed bone.
In patients receiving antiresorptive medication, treatment is coordinated with the oncologist or physician responsible for prescribing it.
A typical treatment course consists of 30 to 40 sessions, depending on the severity and stage of the osteonecrosis.