Hyperbaric Oxygen Therapy as an Adjunct for Treating an Individual with Poorly Healing Bilateral Mandibular Fractures Suspect of Developing Towards Osteomyelitis: A Case Report and Clinical Experience.

PURPOSE: To present a case that benefited from utilizing hyperbaric oxygen therapy in conjunction with antibiotics for a non-healing mandibular fracture that was highly suspicious of osteomyelitis. Also, to discuss research set forth by Undersea and Hyperbaric Medical Society that supports the use hyperbaric oxygen in such cases. CASE: A 25-year-old male status post fist to face resulting in bilateral mandibular fracture. He underwent two surgeries in an attempt to plate the fracture with the assistance of a bone graft. After failure of the bone graft and significant soft tissue wound breakdown, the surgeon was concerned for osteomyelitis and began therapy with intravenous antibiotics and hyperbaric oxygen therapy. CONCLUSION: The patient completed 30 hyperbaric oxygen treatments and 30 d of intravenous antibiotics. Clinically, the patient responded well and showed healed intraoral wounds and an objective decrease in erythrocyte sedimentation rate over the course of treatment. Unfortunately, on serial imaging the patient showed to have fibrous non-bony union of left fracture site. Even though the patient will need a final definitive plate for his fracture, it will be performed from an extraoral approach with no evidence of underlying infection.

New perspectives on the conservative management of osteoradionecrosis of the mandible: A literature review.

Over the last decades, several therapeutic options were considered in the treatment of the osteoradionecrosis (ORN) of the mandible, including supportive measures, ultrasound therapy, corticosteroids, hyperbaric oxygen, surgical resection with reconstruction, and, more recently, drugs capable of reversing the fibroatrophic process. Once established, the ORN does not spontaneously disappear and a standard treatment has not yet been defined. The clear clinical effectiveness of hyperbaric oxygen therapy (HBOT) varies according to the literature and there are some economic/logistic issues to be considered; the triplet tocopherol/pentoxifylline/clodronate demands greater evidence from randomized clinical trials and also resilience from the patient, given the long treatment duration and its possible side effects. Controversy around the ideal treatment of the initial stage ORN of the mandible persists. More rigorous randomized prospective trials are essential. The purpose of this article was to review the relevant literature on the physiopathology of ORN of the mandible and discuss the new perspectives of its conservative treatment. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1708-1716, 2016.

BMP-2 and bFGF in an irradiated bone model.

INTRODUCTION: Basic fibroblast growth factor (bFGF) is considered to enhance angiogenesis and to support bone formation in the presence of vital bone cells. Bone morphogenetic protein-2 (rhBMP-2) is known to induce bone formation. The aim of this study was to analyze the effect of bFGF and rhBMP-2 in the irradiated mandible. MATERIAL AND METHODS: The right mandibles of 24 rats were irradiated with a single dose of 20 Gy at a high-dose-rate (HDR) after loading machine (bio effective equivalent dose to ca. 45 x 2 Gy). After 12 weeks 100 microg rhBMP-2 (n=6 animals, group 1), 100 microg bFGF (n=6 animals, group 2) and 100 microg rhBMP-2 plus 100 microg bFGF (n=6 animals, group 3) were injected along the right mandible (left mandible: no irradiation, no growth factor). Another 6 animals (group 4) remained untreated after the irradiation. After another 7 weeks the specimens were examined by non-decalcified histology. RESULTS: Bone apposition of the experimental versus control sides was not statistically significantly different when one of the growth factors was applied alone (rhBMP-2: p=0.917; bFGF: p=0.345). Average bone apposition was significantly decreased on the experimental sides of group 3 (rhBMP-2+bFGF: p=0.046) and group 4 (p=0.008). Average bone densities were unaffected in all settings (for all p>0.1). CONCLUSIONS: The application of bFGF and the application of rhBMP-2 alone did result in predictable bone generation in the irradiated mandible with the bone apposition being equal to that of the non-irradiated side. The application of both growth factors together or none at all after irradiation results in significantly reduced bone apposition.

Use of osseointegrated implants in the restoration of head and neck defects.

Osseointegrated implants can be applied to facilitate retention, stability, and support for facial and intraoral prostheses used to restore head and neck defects. At the University of California, Los Angeles, Maxillofacial Prosthetics Clinic, retrospective studies have indicated that in nonirradiated maxillectomy patients, implant survival rates are 82.6 percent. In mandibles reconstructed with fibula free flaps, survival rates are 94.6 percent. Similarly, high implant survival rates have been observed for most sites used to support facial prostheses. Cumulative six-year survival rates for auricular sites exceed 95 percent and for floor of nose sites, success rates exceed 87 percent. However, survival rates are low (53 percent) for implants placed in the frontal bone for retention of orbital prostheses and even lower for irradiated bone sites ranging from 63 percent in the maxilla to 27 percent in the orbit.

Effect of age and repeated hyperbaric oxygen treatments on vagal tone.

OBJECTIVES: To evaluate the influence of repeated hyperbaric oxygen (HBO2) exposures and age on vagal response to hyperbaric oxygenation, and to evaluate the timing of changes in vagal activity during the treatments. STUDY DESIGN: Open, controlled, non-randomized study. METHODS: Heart rate variability of 23 patients with chronic osteomyelitis or radionecrosis of the jaw or reconstructive surgery of the facial region was studied during repeated treatments. During each treatment, the patients were exposed to HBO2 at 2.5 ATA and heart rate variability was measured using power spectral analysis before compression, three times at 2.5 ATA and during and after decompression. The patients were grouped according to age (Cut-off point 50 years). Statistical analysis was carried out using analysis of variance for repeated measurements. RESULTS: Repeated exposures did not change vagal response to hyperbaric oxygenation. Vagal activity measured by HF power increased significantly in both age groups during the HBO2 exposures but there were no significant difference between the groups in the response. However, the level of HF power was significantly higher in the subjects under 50 years old. Significant differences between consecutive measurements were related to pressure changes. CONCLUSIONS: Repeated therapeutic HBO2exposures are not causing permanent changes in vagal control of the heart. Vagal responsiveness to hyperbaric hyperoxia is preserved in advanced age.

[Mature bone radionecrosis: from recent physiopathological knowledge to an innovative therapeutic action]. / Radionécrose de l'os mature: connaissance physiopathologique récente motrice d'une thérapeutique médicale innovante.

Osteoradionecrosis is a severe radiotherapy (RT) injury by healing failure, late effect and spontaneously irreversible by tissue death. Histologically, it consists in a pagetoid mosaic that combines a defective osteogenesis with an osteoclastic osteolysis and more marginally an osteolytic osteolysis, turned to account to fibroblastic and collagenic fibrosis. Several pathogenic hypotheses favor sometimes a vascular hypoxic hypotheses, sometimes a fibro-atrophic hypothesis. Various events start up or favour ORN as traumatisms (dental extraction, surgery,...) or bacterian infection on fistula. In clinic, adult mature bone concerned is the mandible after head and neck RT by septic ORN, and the hip after pelvic RT by aseptic ORN. For each, epidemiology, clinic and therapeutic aspects are developed. Usual therapeutic attitudes consisted in restriction of defavorable associated events (dental extraction, infection, RT dose, chemotherapy,...) and devitalized tissue removal. Physiopathological therapeutic innovatives aspects are proposed to struggle against radiation-induced fibrosis associated and to limit bone destruction.

Hyperbaric oxygen treatment and pulmonary function.

Hyperbaric oxygen (HBO2) treatment exposes the lungs to the potentially toxic effect of free oxygen radicals and may lead to impairment of pulmonary function. HBO2 significantly improves wound healing in patients with osteoradionecrosis of the mandible following radiation therapy for intraoral cancer. In 18 consecutive patients with osteoradionecrosis of the mandible, pulmonary function was assessed during 6 wk of HBO2 treatment, applied daily in a monoplace chamber for 90 min and at a partial oxygen pressure of 2.4 atm abs. Pretreatment forced vital capacity (FVC) was 104 +/- 14% (mean +/- SD) of a reference population, the 1 s forced expiratory volume (FEV1) 95 +/- 20%, total lung capacity (TLC) 100 +/- 13%, and the carbon monoxide diffusing capacity (DL(CO)) 81 +/- 17% (P < 0.05, compared to reference population). These parameters remained unchanged throughout the treatment period (after 6 wk and expressed relative to the percentage of the expected value at baseline): deltaFVC: +4 +/- 8%; deltaFEV1: -2 +/- 4%; deltaTLC: +2 +/- 5%; deltaDL(CO): 0 +/- 9%; deltaRV 0 +/- 11%. It is concluded that intermittent HBO2 treatment in a monoplace chamber has no persistent effect on pulmonary function and can be offered even to patients with a reduced diffusing capacity.

[Osteoradionecrosis. A review of the literature]. / L'ostéoradionécrose. Une revue de la littérature.

Osteoradionecrosis is a severe complication of radiotherapy characterized by the following sequence: radiation, trauma, bone exposure. The radiation reduces the vascularization potential of the tissues which leads to a hypoxic state that jeopardizes cellular activity and collagen formation. The diagnosis of osteoradionecrosis relies on the clinical examination of chronically exposed bone. Although this type of lesion is not limited to the jaws, the ratio between mandible and maxilla is 24:1. The severity of the lesion is a function of the radiation dosage. The main etiological factors of osteoradionecrosis are related to dental and periodontal pathology as well as to tooth extraction performed after, during or shortly before radiotherapy. Edentulous patients are less exposed to osteoradionecrosis than dentulous patients. Local treatment and antibiotic therapy are initially performed in mild cases. Surgical measures with hemiresection or block resection are indicated depending on the severity of the lesion. Some authors regard hyperbaric oxygen treatment as an efficient therapeutic and preventive technique. Prevention is of major concern. It requires a careful evaluation of soft and hard tissues of the oral cavity as well as the organization of an intensive prophylaxis program. Patient compliance is a prerequisite. This article is a literature review on osteoradionecrosis with its symptoms, incidence, pathogenesis, treatment and prevention.