Treatment of Osteoradionecrosis of the Jaw: The Case Against the Use of Hyperbaric Oxygen

Use of Phototherapy and Er-YAG Laser in the Management of Mandible Osteoradionecrosis: A Case Report

Introduction: Osteoradionecrosis (ORN) is a secondary complication from radiotherapy, which is difficult to manage and significantly reduces the life quality of the affected patients. Case Report: A 59-year-old female patient, diagnosed with infiltration by squamous cell carcinoma in the left cervical region, underwent adjuvant cervical-facial radiotherapy with a total dose of 66.6 Gy of radiation. Eight years after the diagnosis, the patient underwent multiple extractions and, subsequently, the installation of osseointegrated implants, evolving to extensive intraoral bone exposure associated with oral cutaneous fistula. The patient was initially exposed to photobiomodulation therapy (PBMT), with a low-power laser at wavelengths of 660 nm and 808 nm, and thereafter to antimicrobial photodynamic therapy (aPDT). After an improvement in the clinical condition and resolution of the oral cutaneous fistula, a surgical procedure with the Er: YAG laser was performed to remove the remaining necrotic bone. Once the ORN condition was completely treated, the patient's oral rehabilitation was implemented by the installation of an upper mucous-supported total prosthesis and a lower implant-supported prosthesis. Conclusion: The patient is in a clinical follow-up and has no signs of bone necrosis recurrence, suggesting that low and high-power laser treatment can be an effective therapeutic alternative to resolve this condition.

Leukocyte- and platelet-rich fibrin as an adjuvant to the surgical approach for osteoradionecrosis: a case report

We present a case of osteoradionecrosis treated with leukocyte- and platelet-rich fibrin (LPRF) and surgery and followed up with clinical and tomographic investigations. A 65-year-old woman presented with pain in the posterior region of the right palate. Her medical history included cardiovascular disease and squamous cell carcinoma in the anterior region of the floor of the mouth that had been treated with intensity-modulated radiation therapy. Measurements of isodose curves showed a full dosage of 6,462.6 cGy in the anterior mandibular region, whereas that in the posterior region on the right side of the maxilla reached 5,708.1 cGy. Osteotomy was performed using rotary instruments, and debridement and placement of two LPRF membranes were also carried out. New gum tissue with no bone exposure was noted 14 days postoperatively. Tissue repair was complete, and the patient had no further complaints. During a 39-month follow-up period, the oral mucosa remained intact, and the patient was rehabilitated with a new upper denture. Since there is no consensus regarding the best protocol to treat osteoradionecrosis, LPRF might be an interesting adjuvant to a surgical approach. The use of LPRF is simple and reduces operational costs, time of handling, probability of technical failure, and associated morbidities for patients with osteoradionecrosis.

Hyperbaric oxygen treatment did not significantly affect radiation injury in the mandibular area of rats

OBJECTIVE

Hyperbaric oxygen therapy (HBOT) has been used to enhance microcirculation and thereby oxygen tension in tissues. The present study aimed to investigate the effect of HBOT on radiation injury in the mandibular area of rats.

STUDY DESIGN

The left mandibles of rats were irradiated by external radiotherapy (15 Gy every other week for a total of 75 Gy). Four HBOT strategies were used: 2 prophylactic groups receiving HBOT either between each radiation treatment or immediately following terminated radiation treatment, and 2 therapeutic groups receiving HBOT after the latent period of 6 weeks after irradiation either every day (standard HBOT protocol) or 3 days a week for 6 weeks. Tissue samples of the irradiated area were taken from skin, the salivary gland, and the mandible. All tissues were stained with hematoxylin and eosin for morphologic examination. Furthermore, skin samples were stained with CD31 for blood vessel analysis.

RESULTS

There was no change in blood vessel density or morphology between controls and HBOT tissues after radiation. The dentin of 2 of the 5 rats that received HBOT either normalized or was not affected by irradiation.

CONCLUSIONS

HBOT did not affect radiation injury of the mandibular area in rats within 12 weeks after irradiation.

The role of hyperbaric oxygen therapy in the prevention and management of radiation-induced complications of the head and neck - a systematic review of literature

Radiation therapy for the treatment of head and neck cancer can injure normal tissues and have devastating side effects. Hyperbaric oxygen (HBO) is known to reduce the severity of radiation-induced injury by promoting wound healing. While most of the research in literature has focused on its efficacy in osteonecrosis, HBO has other proven benefits as well. The aim of this review was to identify the various benefits of hyperbaric oxygen therapy in patients who have undergone radiation for head and neck cancer. An electronic database search was carried out to identify relevant articles and selected articles were reviewed in detail. The quality of evidence for each benefit, including preserving salivary gland function, preventing osteonecrosis, dental implant success, and overall quality of life, was evaluated. Evidence showed that HBO was effective in improving subjective symptoms of xerostomia, swallowing, speech and overall quality of life. There was no conclusive evidence to show that HBO improved implant survival, prevented osteonecrosis, or improved salivary gland function. The high costs and accessibility of HBO therapy must be weighed against the potential benefits to each patient.

Osteoradionecrosis of the jaws: definition, epidemiology, staging and clinical and radiological findings. A concise review

Osteoradionecrosis (ORN) of the jaws is a pernicious complication of radiation therapy for head and neck tumours. This article aims to provide an update on data related to the definition, epidemiology, staging, and clinical and radiological findings of ORN of the jaws. Using certain keywords, an electronic search was conducted spanning the period from January 1922 to April 2014 to identify the available related investigations. Pooled data were then analysed. ORN is described as exposed irradiated bone that fails to heal over a period of 3 months without evidence of persisting or recurrent tumour. The prevalence of ORN varies in the literature. Several staging or scoring systems of ORN have been proposed. Clinical findings include ulceration or necrosis of the mucosa with exposure of necrotic bone. Radiological findings are not evident in the early stages of ORN. Furthermore ORN may not be apparent in imaging even when the disease is advanced. Taking into account the severity of ORN and the difficulties in diagnosing it early and accurately, the clinician should be aware of this complex entity in order to prevent its appearance or the development of more severe complications.

Osteoradionecrosis and medication-related osteonecrosis of the jaw: similarities and differences

The purpose of this study was to compare medication-related osteonecrosis of the jaw (MRONJ) with osteoradionecrosis (ORN). Group 1 comprised 74 MRONJ patients (93 lesions) and group 2 comprised 59 ORN patients (69 lesions). Patient characteristics, clinical presentation of the lesions, the presence of complications, and the relationship with previous dental extractions were analyzed for both groups. Significant differences were found between the groups with regard to the characteristics of the patient populations, extraction as the precipitating event, the type of initial complaint, the prevalence of pain, and the location of the lesions. In the ORN group, significantly more patients complained of pain (P=0.0108) compared with the MRONJ group. Furthermore, significantly more pathological fractures (P<0.0001) and skin fistulae (P<0.0001) occurred in the ORN group. The treatment was more often conservative in the MRONJ group than in the ORN group (61.3% vs. 36.2%). Despite similarities in terms of imaging, risk factors, prevention, and treatment, MRONJ and ORN are two distinct pathological entities, as highlighted by the differences in patient characteristics, the initial clinical presentation, course of the disease, and outcome.

Prevention of osteoradionecrosis of the jaws by low-intensity ultrasound in the dog model

The prevention of osteoradionecrosis of the jaws (ORNJ) is very important because of the current absence of effective therapies for this disease. The aim of this study was to determine whether low-intensity ultrasound has a preventive effect on ORNJ. Sixty healthy adult dogs were divided randomly into three groups: group A (radiotherapy alone), group B (radiotherapy followed by low-intensity ultrasound treatment), and a control group. The development of ORNJ was assessed and the rate of occurrence of ORNJ was compared between groups A and B. Micro-computed tomography, haematoxylin-eosin staining, and immunofluorescence were used to evaluate the microstructure of the mandible and changes in microvascular density in all groups. All animals in group A and group B (ultrasound applied for 30 days) developed ORNJ. Alveolar bone density was 609.48±53.77HU in group A and 829.65±81.46HU in group B (P=0.008). The trabecular bone volume fraction, bone surface area/bone volume ratio, trabecular thickness, and trabecular number were all lower in group A than in group B (P=0.037, P=0.022, P=0.017, and P=0.034, respectively). Haematoxylin-eosin staining showed that the Haversian canals in the osteons had expanded significantly in group A, with collagen fibres losing their circular orientation; group B tended to show typical osteons. The microvascular density in group A was decreased. In conclusion, the use of low-intensity ultrasound in the dog appears not to prevent the incidence of ORNJ, however it does somewhat improve vascularity and bone quality at the microscopic level, which contribute to ORNJ healing.

An Athymic Rat Model for Mandibular Osteoradionecrosis Allowing for Direct Translation of Regenerative Treatments

Objective

We aim to create a model of mandibular osteoradionecrosis in athymic rats. Athymic rats provide an immunosuppressed environment whereby human stem cells and biomaterials can be used to investigate regenerative solutions for osteoradionecrosis, bridging the gap between in vivo testing and clinical application.

Study Design

Prospective animal study.

Setting

Academic otolaryngology department laboratory.

Subjects and Methods

After Institutional Animal Care and Use Committee approval, 10 athymic nude rats were divided into 2 groups. The experimental group (n = 6) underwent irradiation (20 Gy), while the control group (n = 4) underwent sham irradiation catheter placement only. All 10 rats underwent extraction of the second mandibular molar 7 days later. The rats were sacrificed 28 days after dental extraction, and their mandibles were harvested. The mandibles were examined with histologic analysis and bone volume analysis based on 3-dimensional micro–computed tomography.

Results

All 10 rats survived the experiment period. Radiographic and histologic analysis revealed decreased bone formation in the experimental group compared with the control group. Jaw region volume ratio was 0.83 for the experimental group versus 0.97 in the control group ( P = .003). The region-of-interest volume ratio was 0.75 in the experimental group and 0.97 in the control group ( P = .005). Histologically, there were increased osteoclasts ( P = .02) and decreased osteoblasts ( P = .001) as well as increased fibrosis in the experimental group versus the control group.

Conclusion

Mandibular osteoradionecrosis can be effectively and reproducibly produced in an athymic rat model. This will allow further research to study regenerative medicine in an athymic rat model.

Osteoradionecrosis of the mandible: a review

BACKGROUND

Osteoradionecrosis is a serious complication of radiotherapy that often leads to severe facial deformity, pain, pathological fracture, sequestration of devitalized bone, and orocutaneous fistulas. Preventive measures for osteoradionecrosis are the best treatment plan to avoid osteoradionecrosis. Radical surgery is indicated when conservative methods fail or when severe bone and soft-tissue necrosis prevails.

CASE REPORT

The purpose of this paper is to explore the recent theories about the definition, classification, incidence, and pathophysiology of osteoradionecrosis (ORN) of the jaws. The predisposing and risk factors for the development of osteoradionecrosis based on the literature review along with case report are also discussed.

DISCUSSION

A better understanding on the risk factors responsible for causing ORN and the underlying pathophysiology may improve our ability to prevent this complication and help to improve the prognosis for those being treated for osteoradionecrosis.

Effect of hyperbaric oxygen treatment on oxygen tension and vascular capacity in irradiated skin and mucosa

The aim of this study was to evaluate the effect of hyperbaric oxygen therapy (HBOT) on vascular function and tissue oxygenation in irradiated facial skin and gingival mucosa. Twenty-two patients, aged 51-90 years, were randomly allocated to a treatment or control group. All had a history of radiotherapy (50-70 Gy) to the orofacial region 2-20 years previously. Skin and mucosal perfusion were recorded with laser Doppler flowmetry (LDF). Tissue oxygenation was recorded by transcutaneous oximetry (TcPO(2)). Measurements were taken before HBOT and 3 and 6 months after a mean of 28 HBOT sessions (partial pressure of oxygen of 240 kPa for 90 min). For control subjects, measurements were taken on two occasions 6 months apart. After HBOT, blood flow in mucosa and skin after heat provocation increased significantly (P < 0.05). TcPO(2) increased significantly in the irradiated cheek (P < 0.05), but not at reference points outside the field of radiation. There were no differences between the 3- and 6-month follow-ups. In the control group, no significant changes in LDF or TcPO(2) were observed. It is concluded that oxygenation and vascular capacity in irradiated facial skin and gingival mucosa are increased by HBOT. The effects persist for at least 6 months.

Etiology and treatment of osteonecrosis of the mandible

AIM OF THE STUDY

Post-radiogenic osteonecrosis of the mandible is a serious complication in patients with combined treated head/neck tumors. Osteonecrosis of the mandible can also occur following administration of bisphosphonates. In the present article we would like to present our experiences over the last five years in treating both bisphosphonate-associated osteonecrosis and osteoradionecrosis.

MATERIAL AND METHODS

Of the patients treated in our hospital for bone necrosis of the mandible between January 2005 and June 2010, 16 were diagnosed with infected osteoradionecrosis and 10 with bisphosphonate-associated osteonecrosis. The patients with osteoradionecrosis were administered the classic osteomyelitis treatment. The same procedure was carried out on 5 of the 10 patients with bisphosphonate-associated osteonecrosis; the remaining 5 were treated conservatively due to advanced bone infection. The bone biopsies and specimens of both entities yielded by the surgical interventions were examined histologically after decalcification.

RESULTS

Of the 16 patients treated for infected osteoradionecrosis, 7 recovered after decortication and long-term antibiosis. In 7 cases consolidation did not occur until after osseous continuity resection. In 2 cases the progress of the intraosseous infection could not be stopped with treatment. A typical first symptom of bisphosphonate-associated osteonecrosis was an alveolus that would not heal after a tooth extraction. In 50% of patients with bisphosphonate-associated osteonecrosis recovery was successful with a combination of surgery and long-term antibiosis. In the other patients with advanced bisphosphonate-associated osteonecrosis no definitive cure for the infection of the necrotic bone was possible.

CONCLUSION

In terms of treatment, osteoradionecrosis proves complex, yet easier to treat than bisphosphonate-associated osteonecrosis. The removal of the infected bone tissue is often necessary, but it does not always lead to recovery. Therefore it can be concluded that prevention of intraosseous infection by consistent pretherapeutic dental hygiene is especially important.

The pacific chapter annual meeting of the undersea & hyperbaric medical society

The following is the summary report on the UHMS Pacific Chapter Annual Meeting held in Long Beach in October 2010. The conference provided the latest updates on scientific, technical and organizational aspects of Hyperbaric and Diving Medicine. Invited speakers gave series of lectures dealing with current standards of clinical practice and presenting the results of laboratory investigations with particular emphasis on mechanisms of hyperbaric oxygen therapy. Scientific sessions were accompanied by vendor exhibits and social events.