Hyperbaric-Oxygen Therapy
Hyperbaric oxygen may be beneficial in healing or preventing radiation injuries to the bone (osteoradionecrosis) or soft tissue (see review.) Patients who have a high dose of radiation to the jaw bone (anything over about 5,000 rads) may have problems healing if they later have dental work (particularly tooth extractions.) It's generally preferable to have all necessary teeth pulled prior to radiation to avoid healing problems later. Patients who need teeth removed after radiation should consult an oral surgeon experienced in this area. Many oral surgeons put patients on a hyperbaric protocol as a prevention to avoid healing problems (osteo-radionecrosis of the bone.) Some of the basic information about hyperbaric oxygen is noted below. (also see AHCM protocols

Hyperbaric oxygen — 100 percent oxygen at two to three times the atmospheric pressure at sea level — can result in arterial oxygen tension in excess of 2000 mm Hg1 and oxygen tension in tissue of almost 400 mm Hg.Such doses of oxygen have a number of beneficial biochemical, cellular, and physiologic effects

Radiation-Induced Tissue Injury (NEJM 1996;334:1642)

Irradiated tissues lose the capacity for restorative cellular proliferation, leading to decreased vascularity, local hypoxia, and eventually, necrosis. This loss manifests itself clinically as edema, ulceration, bone necrosis, increased risk of infection, and poor wound healing, processes that can persist for years. One hundred percent oxygen at 1 atmosphere produces insufficient tissue oxygen gradients for wound healing in irradiated tissue, but higher arterial partial pressures of oxygen result in new blood-vessel growth and partial healing. Before hyperbaric-oxygen therapy was available, reconstruction of previously irradiated mandibular tissue in patients with oropharyngeal and other head and neck tumors was often unsuccessful, with complications, including osteonecrosis, soft-tissue radionecrosis, mucositis, dermatitis, and laryngeal radionecrosis, developing in 50 to 60 percent of patients. With hyperbaric oxygen, success rates of up to 93 percent have been reported among selected patients.

In an unblinded, controlled trial, 30 hyperbaric-oxygen treatments were more effective in preventing the development of mandibular osteoradionecrosis than penicillin in 37 previously irradiated patients In a preliminary analysis of 160 irradiated patients undergoing soft-tissue flap surgery, preoperative therapy with hyperbaric oxygen was superior to routine care in reducing wound dehiscence, infections, and delayed wound healing. Current protocols for the prevention and treatment of osteoradionecrosis involve 30 preoperative hyperbaric-oxygen sessions at 2.4 atmospheres for 90 minutes each, followed by 10 treatments after surgery. See some recent studies below:

 
J Am Dent Assoc 1985 Jul;111(1):49-54

Prevention of osteoradionecrosis: a randomized prospective clinical trial of hyperbaric oxygen versus penicillin.

Marx RE, Johnson RP, Kline SN

A prospective randomized trial comparing hyperbaric oxygen and systemic antibiotics in the prevention of osteoradionecrosis was presented. The results indicated, in a high-risk population who required tooth removal in irradiated mandibles, that up-front hyperbaric oxygen produced an incidence of osteoradionecrosis of 5.4% as compared with the antibiotic group of 29.9% (P = .005). Hyperbaric oxygen should be considered a prophylactic measure when post-irradiation dental care involving trauma to tissue is necessary.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995 Jul;80(1):12-6

Hyperbaric oxygen treatment of osteoradionecrosis of the mandible. Experience in 29 patients.

van Merkesteyn JP, Bakker DJ, Borgmeijer-Hoelen AM

Department of Oral and Maxillofacial Surgery, Academic Hospital Leiden, The Netherlands.

In recent years hyperbaric oxygen has gained an important role in the treatment of osteoradionecrosis of the mandible. In the treatment of 29 patients with osteoradionecrosis of the mandible, a combination of surgical debridement, antibiotics, and hyperbaric oxygen was used in 27 cases. In 20 of the 29 patients the osteoradionecrosis was considered to be resolved after treatment. In 31% of the patients, the continuity of the mandible was lost. It was concluded that combined treatment of surgical debridement, antibiotics, and hyperbaric oxygen gives acceptable results and may, when used in an early phase of the disease, limit the number of patients who lose continuity of the mandible.

Br J Oral Maxillofac Surg 1996 Oct;34(5):424-7

Does hyperbaric oxygen have a role in the management of osteoradionecrosis?

Wood GA, Liggins SJ

Department of Oral and Maxillofacial Surgery, Canniesburn Hospital, Bearsden, Glasgow, UK.

A retrospective study of 12 episodes of osteoradionecrosis treated with hyperbaric oxygen (HBO) in 11 patients was carried out. The cases had been previously treated by more conventional methods including surgery, unsuccessfully. All the cases treated by HBO had a successful outcome, although 83% of the patients required concomitant surgery to remove necrotic bone. The costs and contra-indications for hyperbaric oxygen therapy are discussed.

Aust Dent J 1999 Dec;44(4):243-7

Hyperbaric oxygen in the prevention of osteoradionecrosis of the jaws.

Vudiniabola S, Pirone C, Williamson J, Goss AN

Oral and Maxillofacial Surgery Unit, University of Adelaide.

Patients who have had their jaws irradiated as part of management of head and neck malignancy are at risk of osteoradionecrosis (ORN) following tooth extraction. Thirty-seven patients with a history of irradiation to the jaws were managed during a four year period. Twenty-nine patients received hyperbaric oxygen therapy (HBO) consisting of 20 treatments before surgery and ten treatments after. Only one (4 per cent) developed ORN. Seven patients who did not have HBO and one who did (15 per cent) developed ORN. The need for prophylactic treatment with HBO is discussed. It is recommended that prophylactic HBO is used prior to surgery for irradiated facial bones.

Laryngoscope 1993 Jun;103(6):605-8

Role of hyperbaric oxygen therapy in the management of mandibular osteoradionecrosis.

Mounsey RA, Brown DH, O'Dwyer TP, Gullane PJ, Koch GH

Department of Otolaryngology, Toronto Hospital, Ontario, Canada.

Hyperbaric oxygen (HBO) has been used as a tool in the management of osteoradionecrosis (ORN). However, it has not been conclusively proven to be of benefit. The precise role and guidelines for its use also have not been clearly defined. This report retrospectively analyzes 41 patients treated at the Hyperbaric Chamber Unit at the Toronto Hospital (Toronto General Division) with proven mandibular ORN from 1980 to 1985. The results show that 83% of the patients had a significant improvement with HBO therapy, judged by at least a 50% decrease in the size of the exposed bone, closing of the fistulous tract, or complete relief of symptoms. Within the group of patients who were significantly improved, 15% showed complete resolution of ORN. Seven (17%) of the patients did not benefit from the HBO. All seven patients had radiological evidence of dead bone. Based on these observations, the following conclusions can be made: 1. HBO is of benefit in the management of ORN. 2. Patients with ORN may be divided into two groups: mild and severe. 3. Cases of mild ORN will heal with HBO alone, but, in severe ORN, surgery is necessary to remove dead bone. 4. All patients with ORN should receive dental evaluation, local wound care, and a strict oral hygiene regimen. Diseased teeth should be removed prior to radiotherapy. Subsequently, any teeth that became abscessed should be extracted in conjunction with prophylactic HBO. Antibiotics play an ancillary role in the management of ORN. For patients who have received radiation to the mandible, the authors propose regular follow-up in order to detect ORN at a time when HBO can arrest the disease.

Oral Surg Oral Med Oral Pathol 1987 Mar;63(3):280-6

Hyperbaric oxygen in the treatment of osteoradionecrosis: a review of its use and efficacy.

Fattore L, Strauss RA

Hyperbaric oxygen (HBO) therapy is an established technology that is proving to be effective in the treatment of osteoradionecrosis. However, the studies that have shown this treatment modality to be effective have not established the optimum pressures, times of exposure, and frequency and number of treatment necessary for healing. In addition, most of the studies used HBO as an adjunctive treatment in the management of refractory osteoradionecrosis. The efficacy of HBO as a primary treatment modality has not as yet been established. Strictly controlled clinical trials are necessary for identification of patients who are likely to respond to HBO without aggressive surgery, to delineate a timetable for treatment of patients with HBO, and to coordinate surgery with HBO to resolve osteoradionecrosis when a significant amount of bone loss is involved.

SADJ 1998 Oct;53(10):469-71

A review of the Marx protocols: prevention and management of osteoradionecrosis by combining surgery and hyperbaric oxygen therapy.

Cronje FJ

Institute for Aviation Medicine, Hyperbaric Oxygen Therapy Department, Pretoria.

The 30/10 protocol is employed in the treatment of established osteoradionecrosis. No surgery should be attempted before the first 30 HBO treatments have provided sufficient angiogenesis to support surgical wounding. After 30 treatments surgical management can be staged according to the extent of improvement achieved after HBO and the size of sequestrum or area of osteolysis. If the ORN extends to the inferior border of the mandible or if it manifests as an orocutaneous fistula or pathological fracture, discontinuity resection of the necrotic bone and soft tissue will be required to resolve the disease. Unless HBO and surgery are combined in the management of ORN, the results are not long lasting or satisfactory. Even though resection of stage three ORN seems unduly aggressive, it has stood the test of time. By using the Marx protocols in the treatment of ORN, more than 95 per cent of patients can be successfully cured of their disease with predictable, functional and aesthetically acceptable outcomes.