Utility of Hyperbaric Oxygen in Treatment of Bisphosphonate-Related Osteonecrosis of the Jaws

Interventions for managing medication-related osteonecrosis of the jaw

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction experienced by some individuals to certain medicines commonly used in the treatment of cancer and osteoporosis (e.g. bisphosphonates, denosumab, and antiangiogenic agents), and involves the progressive destruction of bone in the mandible or maxilla. Depending on the drug, its dosage, and the duration of exposure, this adverse drug reaction may occur rarely (e.g. following the oral administration of bisphosphonate or denosumab treatments for osteoporosis, or antiangiogenic agent-targeted cancer treatment), or commonly (e.g. following intravenous bisphosphonate for cancer treatment). MRONJ is associated with significant morbidity, adversely affects quality of life (QoL), and is challenging to treat. This is an update of our review first published in 2017.

OBJECTIVES

To assess the effects of interventions versus no treatment, placebo, or an active control for the prophylaxis of MRONJ in people exposed to antiresorptive or antiangiogenic drugs. To assess the effects of non-surgical or surgical interventions (either singly or in combination) versus no treatment, placebo, or an active control for the treatment of people with manifest MRONJ.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched four bibliographic databases up to 16 June 2021 and used additional search methods to identify published, unpublished, and ongoing studies.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing one modality of intervention with another for the prevention or treatment of MRONJ. For 'prophylaxis of MRONJ', the primary outcome of interest was the incidence of MRONJ; secondary outcomes were QoL, time-to-event, and rate of complications and side effects of the intervention. For 'treatment of established MRONJ', the primary outcome of interest was healing of MRONJ; secondary outcomes were QoL, recurrence, and rate of complications and side effects of the intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, extracted the data, and assessed the risk of bias in the included studies. For dichotomous outcomes, we reported the risk ratio (RR) (or rate ratio) and 95% confidence intervals (CIs).

MAIN RESULTS

We included 13 RCTs (1668 participants) in this updated review, of which eight were new additions. The studies were clinically diverse and examined very different interventions, so meta-analyses could not be performed. We have low or very low certainty about available evidence on interventions for the prophylaxis or treatment of MRONJ. Prophylaxis of MRONJ Five RCTs examined different interventions to prevent the occurrence of MRONJ. One RCT compared standard care with regular dental examinations at three-month intervals and preventive treatments (including antibiotics before dental extractions and the use of techniques for wound closure that avoid exposure and contamination of bone) in men with metastatic prostate cancer treated with zoledronic acid. The intervention seemed to lower the risk of MRONJ (RR 0.10, 95% CI 0.02 to 0.39, 253 participants). Secondary outcomes were not evaluated. Dentoalveolar surgery is considered a common predisposing event for developing MRONJ and five RCTs tested various preventive measures to reduce the risk of postoperative MRONJ. The studies evaluated plasma rich in growth factors inserted into the postextraction alveolus in addition to standardised medical and surgical care versus standardised medical and surgical care alone (RR 0.08, 95% CI 0.00 to 1.51, 176 participants); delicate surgery and closure by primary intention versus non-traumatic tooth avulsion and closure by secondary intention (no case of postoperative MRONJ in either group); primary closure of the extraction socket with a mucoperiosteal flap versus application of platelet-rich fibrin without primary wound closure (no case of postoperative MRONJ in either group); and subperiosteal wound closure versus epiperiosteal wound closure (RR 0.09, 95% CI 0.00 to 1.56, 132 participants).  Treatment of MRONJ Eight RCTs examined different interventions for the treatment of established MRONJ; that is, the effect on MRONJ cure rates.  One RCT analysed hyperbaric oxygen (HBO) treatment used in addition to standard care (antiseptic rinses, antibiotics, and surgery) compared with standard care alone (at last follow-up: RR 1.56, 95% CI 0.77 to 3.18, 46 participants).  Healing rates from MRONJ were not significantly different between autofluorescence-guided bone surgery and conventional bone surgery (RR 1.08, 95% CI 0.85 to 1.37, 30 participants). Another RCT that compared autofluorescence- with tetracycline fluorescence-guided sequestrectomy for the surgical treatment of MRONJ found no significant difference (at one-year follow-up: RR 1.05, 95% CI 0.86 to 1.30, 34 participants).  Three RCTs investigated the effect of growth factors and autologous platelet concentrates on healing rates of MRONJ: platelet-rich fibrin after bone surgery versus surgery alone (RR 1.05, 95% CI 0.90 to 1.22, 47 participants), bone morphogenetic protein-2 together with platelet-rich fibrin versus platelet-rich fibrin alone (RR 1.10, 95% CI 0.94 to 1.29, 55 participants), and concentrated growth factor and primary wound closure versus primary wound closure only (RR 1.38, 95% CI 0.81 to 2.34, 28 participants).   Two RCTs focused on pharmacological treatment with teriparatide: teriparatide 20 μg daily versus placebo in addition to standard care (RR 0.96, 95% CI 0.31 to 2.95, 33 participants) and teriparatide 56.5 μg weekly versus teriparatide 20 μg daily in addition to standard care (RR 1.60, 95% CI 0.25 to 1.44, 12 participants).

AUTHORS CONCLUSIONS

Prophylaxis of medication-related osteonecrosis of the jaw One open-label RCT provided some evidence that dental examinations at three-month intervals and preventive treatments may be more effective than standard care for reducing the incidence of medication-related osteonecrosis of the jaw (MRONJ) in individuals taking intravenous bisphosphonates for advanced cancer. We assessed the certainty of the evidence to be very low. There is insufficient evidence to either claim or refute a benefit of the interventions tested for prophylaxis of MRONJ in patients with antiresorptive therapy undergoing dentoalveolar surgery. Although some interventions suggested a potential large effect, the studies were underpowered to show statistical significance, and replication of the results in larger studies is pending. Treatment of medication-related osteonecrosis of the jaw The available evidence is insufficient to either claim or refute a benefit, in addition to standard care, of any of the interventions studied for the treatment of MRONJ.

Novel Cell Therapy Using Mesenchymal Stromal Cell Sheets for Medication-Related Osteonecrosis of the Jaw

Despite medication-related osteonecrosis of the jaw (MRONJ) being first reported in 2003, the optimal treatment and prevention modalities for MRONJ are not clear. As a result, dentistry, oral surgery, and departments involved in the treatment of cancer and bone diseases are struggling with the management of MRONJ. Several cases of MRONJ cannot be managed by conventional treatment strategies recommended in various position papers. Therefore, studies have been conducted to investigate the efficacy of novel therapies for MRONJ. However, the optimal treatment is unknown. Several cell therapies including autologous cell transplantation have been reported for MRONJ. Although the efficacy of cell therapy for MRONJ has been demonstrated, large, statistically accurate clinical trials are lacking. We have been investigating the efficacy of MRONJ treatment using mesenchymal stromal cell (MSC) sheets since 2013 and confirmed its efficacy through various experiments, wherein MSC sheets were transplanted in model rats and beagle dogs with MRONJ-like lesions. Based on these results, we are planning to conduct a clinical trial of MRONJ therapy using periodontal ligament-derived MSC sheets.

Current Trends in Adjuvant Therapies for Medication-Related Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a refractory disease, and a standard protocol for its treatment has not yet been established. In addition, owing to the old age of MRONJ patients and various complications, treatment goals focus on relieving the symptoms and improving the quality of life. For this reason, different treatments such as conservative, surgical, and adjunctive treatments have been attempted. In particular, adjunctive treatment, which is effective for promoting healing and reducing recurrence, is gaining increasing interest, and several studies and clinical trials related to it have been published. Representative adjuvant therapies include teriparatide, recombinant human bone morphogenetic protein-2, hyperbaric oxygen, photobiomodulation and platelet concentrates. All have generally shown beneficial effects; however, no standard protocol for adjunctive treatment exists. Therefore, in this literature review, we briefly summarized the different adjuvant therapies and reviewed clinical reports to help decide whether to use adjuvant therapies in treating patients with MRONJ.

Oral Surgery Procedures in a Patient with Hajdu-Cheney Syndrome Treated with Denosumab-A Rare Case Report

Background: Hajdu-Cheney syndrome (HCS) is a very rare autosomal-dominant congenital disease associated with mutations in the NOTCH2 gene. This disorder affects the connective tissue and is characterized by severe bone resorption. Hajdu-Cheney syndrome most frequently affects the head and feet bones (acroosteolysis). Case report: We present an extremely rare case of a 34-year-old male with Hajdu-Cheney syndrome. The patient was admitted to the Department of Oral Surgery, Medical University of Gdańsk, in order to perform the extraction of three teeth. These teeth were not eligible for conservative treatment and prosthetic reconstruction. The patient was treated with denosumab (angiogenesis and receptor activator of nuclear factor-κB RANK ligand inhibitor, RANKL). Discussion: Denosumab is a monoclonal antibody against RANKL. This drug works through a suppression of osteoclast activity. In cases of patients in which the pathway of the RANK/RANKL/osteoprotegerin is dysregulated, denosumab has been approved for the treatment off-label. In patients receiving denosumab, a delayed wound healing in the oral cavity and osteonecrosis may occur. Dental procedures involving the alveolar bone process (tooth extractions and bone alveoloplasty) may be a risk factor for medication-related osteonecrosis of the jaw (MRONJ). Spontaneous osteonecrosis is rarely observed. MRONJ consists of the destruction of exposed bone, with the exposure persisting for a minimum of 6–8 weeks. This is the first article about an HCS patient treated with denosumab who underwent invasive oral surgery procedures. This case report highlights the difficulties for professionals occurring during the oral surgery procedures in such patients.

Recurrence-Related Factors of Medication-Related Osteonecrosis of the Jaw: A Five-Year Experience

PURPOSE

The treatment of medication-related osteonecrosis of the jaw (MRONJ) is greatly challenging for surgeons. In this study, we reviewed patients with MRONJ treated in our hospital in the past 5 years and explored the risk factors of recurrence.

METHODS

A retrospective cohort study was conducted to review the patients with MRONJ from January 1, 2016 to December 31, 2020. All patients received a monthly intravenous application of zoledronic acid. The primary outcome variable was the treatment outcome during follow-up. The predictor variables were local and systemic factors related to the treatment outcome. Multivariate logistic regression analysis was performed to identify the risk factors of recurrence after MRONJ treatment.

RESULTS

A total of 58 patients (62 sites) were included in this study. In multivariate regression analysis, the risk factor associated with recurrence after MRONJ treatment was the duration of medication of more than 18 months (odds ratio = 7.346; 95% confidence interval: 1.461-36.946; P = .016).

CONCLUSIONS

Using zoledronic acid over 18 months may increase the risk of recurrence in MRONJ patients.

Pycnodysostosis: a case report and literature review concerning oral and maxillofacial complications and their management

OBJECTIVE

There is a lack of knowledge regarding pycnodysostosis (PYCD), which is commonly misdiagnosed as other, similar malformations. This study aims to report a patient with PYCD and conjointly present a comprehensive literature review regarding oral complications after oral surgery procedures.

STUDY DESIGN

This study aims to report a noteworthy case of a 40-year-old woman with PYCD who suffered from a midface defect after iatrogenic fracture during extraction of the upper right molars. A comprehensive electronic search was carried out in January 2020 for detection and analysis of the most commonly encountered dentoalveolar PYCD-related complications. The study was granted an exemption from the local institutional review board.

RESULTS

The electronic search yielded 35 articles reporting 41 PYCD cases with 62 various reported dentoalveolar complications. The survey reported a prevalence of osteomyelitis (n = 39) followed by pathologic fracture (n = 17), iatrogenic fracture (n = 5), and oronasal communication (n = 1).

CONCLUSIONS

This study advocates handling patients with PYCD with care through the use of extensive clinical and radiographic examinations, giving priority to any conservative treatment modalities, atraumatic surgical procedures, prophylactic antibiotic prescriptions, and a regular follow-up schedule to tackle any anticipated complications.

Ozonated oil effect for prevention of medication-related osteonecrosis of the jaw (MRONJ) in rats undergoing zoledronic acid therapy

OBJECTIVES

The aim of this study was to evaluate the preventive effect of ozonated oil on the development of MRONJ-like lesions at tooth extraction sites in rats submitted to zoledronic acid treatment.

MATERIALS AND METHODS

Twelve rats were divided into two groups. Each rat received an injection of zoledronic acid solution once a week for 5 weeks before having its upper first molar extracted. In group 1, the clotted socket was maintained, while in the group 2, the socket was treated with ozonated oil for 10 min/day during 3 days. After euthanasia, block resection was performed for histological analysis. Necrotic bone was defined as the area of the bone with empty osteocyte lacunae and vital bone as the area with osteocyte-occupied lacunae.

RESULTS

There was no statistically significant difference between the groups in the average area of vital bone (p = 0.2248) and the average area of necrotic bone (p = 0.1208). However, the average area of vital bone in group 1 was smaller (24.1 ± 2.9 cells/cm²) than in group 2 (26.8 ± 4.2 cells/cm²), and the average area of necrotic bone in group 1 was higher (7.0 ± 2.5 cells/cm²) than in group 2 (4.0 ± 1.1 cells/cm²), indicating that ozonated oil may reduce the development of osteonecrosis.

CONCLUSIONS

Our findings suggest that ozonated oil might prevent MRONJ-like lesions at tooth extraction sites in rats submitted to a disease induction protocol. Further research should be conducted to confirm this hypothesis.

CLINICAL RELEVANCE

MRONJ has been reported as a complication of surgical dental procedures, and there are currently no predictable preventive therapies.

Medication-related osteonecrosis and osteoradionecrosis of the jaws: Update and current management

Medication related osteonecrosis of the jaws (MRONJ) and osteoradionecrosis of the jaws (ORNJ) are two different diseases of quite similar appearance. MRONJ is mainly due to antiresorptive or antiangiogenic drug therapy and ORNJ to radiotherapy. The present work aimed at presenting and comparing the current knowledge on MRONJ and ORNJ. They both present as an exposure of necrotic bone and differ in some clinical or radiological characteristics, clinical course and mostly in treatment. They share similar risk factors. A tooth extraction is more frequently found as a triggering factor in MRONJ. The frequency of a maxillary localisation seems higher for MRONJ. On computed tomographic images, a periosteal reaction seems characteristic of MRONJ. More frequent pathological fractures seem to occur in ORNJ. It is mandatory, for ORNJ diagnosis, to exclude a residual or recurrent tumour using histological examination. Both MRONJ and ORNJ are challenging to treat and cannot be managed similarly. For both, it would still be worth to optimise awareness within the medical community, patients' oral hygiene and dental cares to improve their prevention and make their incidences decrease. Conservative therapy is more frequently achieved for MRONJ than ORNJ and surgical resection is more often performed for ORNJ. For both diseases, the last treatment possible in refractory cases is a surgical extensive resection with free flap reconstruction. A MRONJ classification is widely used today, whereas no consensus exists to date for ORNJ classification. We propose a classification that could play this role.

Prognosis of medication-related osteonecrosis of the jaws in metastatic prostate cancer patients

OBJECTIVES

The aim of this study was to find out the prognosis of medication-related osteonecrosis of the jaws (MRONJ) in prostate cancer patients who received two different types of antiresorptive agents for bone metastasis.

MATERIALS AND METHODS

We retrospectively surveyed a cohort of 95 metastatic prostate cancer patients with 122 MRONJ lesions treated in a single medical center. Treatment outcomes and prognostic factors were investigated. The cumulative complete response rate was calculated with the Kaplan-Meier method, and significance was examined with the log-rank and Breslow tests. Cox regression was used for the univariate and multivariate analyses of prognostic factors.

RESULTS

The cumulative complete response rate of all patients at 12 months was 37.8%, and that of patients treated with zoledronic acid and denosumab was 22.9% and 70.5%, respectively. Denosumab, pretreatment C-terminal telopeptide of collagen I (CTX) level > 150 pg/ml, and anemia were identified as independent prognostic factors in a multivariate analysis with adjusted hazard ratios of 3.18 (95% confidence interval [CI], 1.24-8.11), 3.24 (95% CI, 1.39-7.53), and 0.42 (95% CI, 0.19-0.93), respectively.

CONCLUSION

A higher pretreatment level of CTX, using denosumab as the antiresorptive agent and without anemia, indicates a better treatment outcome of MRONJ in prostate cancer patients.

Pathogenesis and multidisciplinary management of medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect of bone-modifying agents and inhibits angiogenesis agents. Although the pathogenesis of MRONJ is not entirely clear, multiple factors may be involved in specific microenvironments. The TGF-β1 signalling pathway may have a key role in the development of MRONJ. According to the clinical stage, multiple variables should be considered when selecting the most appropriate treatment. Therefore, the prevention and management of treatment of MRONJ should be conducted in patient-centred multidisciplinary team collaborative networks with oncologists, dentists and dental specialists. This would comprise a closed responsibility treatment loop with all benefits directed to the patient. Thus, in the present review, we aimed to summarise the pathogenesis, risk factors, imaging features, clinical staging, therapeutic methods, prevention and treatment strategies associated with MRONJ, which may provide a reference that can inform preventive strategies and improve the quality of life for patients in the future.

Denosumab-induced osteonecrosis of external auditory canal

Denosumab is the world's first human monoclonal antibody for the treatment of osteoporosis and shares an active pathway with bisphosphonates, strongly suppressing osteoclast activities. This is the first case report describing a possible relationship between the development of osteonecrosis of external auditory canal and denosumab administration. We herein report an 81-year-old woman diagnosed with left osteonecrosis of external auditory canal who had a history of denosumab administration. She underwent left radical mastoidectomy due to being refractory to conservative treatment. No major complications or recurrence were observed in the left ear after surgery, but bone erosion in the right ear has continued to progress slowly despite the cessation of denosumab administration. Otolaryngologists should be aware of the association between osteonecrosis of external auditory canal and denosumab administration and consider performing long-term observation even after cessation.

Multidisciplinary approaches to odontogenic lesions

PURPOSE OF REVIEW

To give an overview of technical considerations and relevant literature in the management odontogenic pathology with involvement of the maxillary sinus.

RECENT FINDINGS

Infections, cysts, benign neoplasms (odontogenic and nonodontogenic), and inflammatory conditions impact the maxillary sinus in various ways, could result in significant expansion within the maxillary sinus and significant infections.

SUMMARY

This manuscript provides an overview of common pathologic entities of the oral cavity proper that impacts the maxillary sinus health, with discussion of the role of the otorhinolaryngologist and the dental specialist.

The Effectiveness of the Low-Level Laser, Antibiotic and Surgical Therapy in the Treatment of Medication-Related Osteonecrosis of the Jaws: A Case Report

Introduction: Bisphosphonates consist of a range of drugs used in the treatment of osteopathy or some osteotropic malignancies. Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse consequence of their use. Conventional treatment is not always effective, so it is necessary to resort to the use of adjuvant therapies. This study aimed to evaluate the effectiveness of the association of surgery, antibiotic therapy and low-level laser (LLL) therapy as a treatment strategy for MRONJ through the presentation of a clinical case. Case Presentation: A 49-year-old female patient presented for the diagnosis and treatment of bone lesions in the maxillae. The patient reported that she had used zoledronate for 1 year. Five years later there were 2 painless bone lesions on both sides of the maxilla, following the extraction of the first upper molars. Clinical, tomographic and histopathologic examination established the diagnosis of MRONJ. The treatment consisted of the curettage of the necrotic bone, antibiotic and thirteen LLL therapy sessions. Integral mucosal healing was observed after a two-month follow-up and no symptoms were detected. The patient was evaluated at 6 and 12 postoperative months without complications. Conclusion: The combination of surgery, antibiotic therapy, and LLL therapy has shown to be effective in the treatment of MRONJ.

Immediate hyperbaric oxygen after tooth extraction ameliorates bisphosphonate-related osteonecrotic lesion in rats

BACKGROUND

This study aims to assess whether hyperbaric oxygen (HBO) applied immediately after tooth extraction could ameliorate medication-related osteonecrosis of the jaw in rats.

METHODS

To evaluate whether osteonecrosis could be successfully induced, healing of extraction maxillary molars was examined in 40 female Sprague Dawley rats received zoledronic acid (7.5 µg/kg) plus dexamethasone (1 mg/kg). Rats were divided into four groups, receiving zero, two, four, or seven injection(s) for 7 days, respectively. Effect of HBO, pressurized to 2.5 atmospheres absolute (ATA) at rate of 0.15 ATA/min with 100% oxygen for 90 minutes, applied immediately after tooth extraction, on the development of osteonecrosis was evaluated. Lesions among groups were compared by size of ulceration, exact area (mm² ) or relative area (%), and by histology.

RESULTS

Unhealed ridge was observed in all nine rats in four and seven injection groups, but none of 10 rats in the control (non-injection) group. Immediate HBO significantly reduced the lesions in rats that received four injections, regardless of the distribution and the total/relative areas of lesions (P <0.01). Histological findings showed the lesions were uncovered epithelium and severe tissue inflammation.

CONCLUSION

This is the first in vivo study demonstrating the HBO applied immediately after tooth extraction effectively decreases the development of medication-related osteonecrosis.

Osteonecrosis of the Jaw After Bisphosphonates Treatment in Patients with Multiple Myeloma

Background:

Bone lytic lesion in Multiple myeloma are the most commonly presented symptoms which require treatment with bisphosphonates (BPs). BPs are providing supportive care, reducing the rate of skeletal morbidity but evidently not abolishing it, the criteria for stopping their administration have to be different from those used for classic antineoplastic drugs, and they should not be stopped when metastatic bone disease is progressing. Osteonecrosis of the jaw (ONJ) has been associated recently with the use of BPs.

Aim:

The aim of these study is to evaluate the incidence of ONJ in patients with MM treated with mixed biphosphonates.

Patients and methods:

We analyzed total 296 myeloma patients (150 male and 146 female). Mostly effected age group with 58,1% is age more than 60 years up to 88 years, diagnosed in our institution in the period 2005-2015. We used intravenous or oral forms of biphosphonates such as pamidronate, ibandronate, clodronate and zolendronic acid. The patients were evaluated for ONJ.

Results:

The incidence of ONJ in our group of patients treated with Bps was 4,6% from our group of 260 patients 87,8% received BPs therapy and patients which haven’t received BPs 12,2%. From this group, 95,4% (248) didn’t show ONJ, and 4,6% (12) showed ONJ. The period of this treatment with BPs is an important risk factor for development of ONJ, average duration of BPs therapy in patients which show adverse effects is 26.8±13.7 months, from the total number of 12 patients that developed ONJ adverse effects, we have 8 patients which received treatment with Zolendronic acid and the remaining 4 patients which were treated with other BPs combinations without Zolendronic acid.

Conclusions:

All patients treated for MM must continue with the therapy with Zolendronic acid and Pamidronate, each patient must be individually treated according to his response of the treatment (dose, frequency and duration of therapy).

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.

Interventions for managing medication-related osteonecrosis of the jaw

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction experienced by some individuals to certain medicines commonly used in the treatment of cancer and osteoporosis (e.g. bisphosphonates, denosumab and antiangiogenic agents) and involves the progressive destruction of bone in the mandible or maxilla. Depending on the drug, its dosage, and the duration of exposure, the occurrence of this adverse drug reaction may be rare (e.g. following the oral administration of bisphosphonate or denosumab treatments for osteoporosis, or antiangiogenic agent-targeted cancer treatment) or common (e.g. following intravenous bisphosphonate for cancer treatment). MRONJ is associated with significant morbidity, adversely affects quality of life (QoL), and is challenging to treat.

OBJECTIVES

To assess the effects of interventions versus no treatment, placebo, or an active control for the prophylaxis of MRONJ in people exposed to antiresorptive or antiangiogenic drugs.To assess the effects of non-surgical or surgical interventions (either singly or in combination) versus no treatment, placebo, or an active control for the treatment of people with manifest MRONJ.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 23 November 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 10), MEDLINE Ovid (1946 to 23 November 2016), and Embase Ovid (23 May 2016 to 23 November 2016). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on language or publication status when searching the electronic databases; however, the search of Embase was restricted to the last six months due to the Cochrane Embase Project to identify all clinical trials and add them to CENTRAL.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing one modality of intervention with another for the prevention or treatment of MRONJ. For 'prophylaxis of MRONJ', the primary outcome of interest was the incidence of MRONJ; secondary outcomes were QoL, time-to-event, and rate of complications and side effects of the intervention. For 'treatment of established MRONJ', the primary outcome of interest was healing of MRONJ; secondary outcomes were QoL, recurrence, and rate of complications and side effects of the intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, extracted the data, and assessed the risk of bias in the included studies. For dichotomous outcomes, we reported the risk ratio (RR) (or rate ratio) and 95% confidence intervals (CI).

MAIN RESULTS

We included five RCTs (1218 participants) in the review. Three trials focused on the prophylaxis of MRONJ. Two trials investigated options for the treatment of established MRONJ. The RCTs included only participants treated with bisphosphonates and, thus, did not cover the entire spectrum of medications associated with MRONJ. Prophylaxis of MRONJOne trial compared standard care with regular dental examinations in three-month intervals and preventive treatments (including antibiotics before dental extractions and the use of techniques for wound closure that avoid exposure and contamination of bone) in men with metastatic prostate cancer treated with zoledronic acid. The intervention seemed to lower the risk of MRONJ: RR 0.10; 95% CI 0.02 to 0.39 (253 participants; low-quality evidence). Secondary outcomes were not evaluated.As dentoalveolar surgery is considered a common predisposing event for developing MRONJ, one trial investigated the effect of plasma rich in growth factors (PRGF) for preventing MRONJ in people with cancer undergoing dental extractions. There was insufficient evidence to support or refute a benefit of PRGF on MRONJ incidence when compared with standard treatment (RR 0.08, 95% CI 0.00 to 1.51; 176 participants; very low-quality evidence). Secondary outcomes were not reported. In another trial comparing wound closure by primary intention with wound closure by secondary intention after dental extractions in people treated with oral bisphosphonates (700 participants), no cases of intraoperative complications or postoperative MRONJ were observed. QoL was not investigated. Treatment of MRONJOne trial analysed hyperbaric oxygen (HBO) treatment used in addition to standard care (antiseptic rinses, antibiotics, and surgery) compared with standard care alone. HBO in addition to standard care did not significantly improve healing from MRONJ compared with standard care alone (at last follow-up: RR 1.56; 95% CI 0.77 to 3.18; 46 participants included in the analysis; very low-quality evidence). QoL data were presented qualitatively as intragroup comparisons; hence, an effect estimate of treatment on QoL was not possible. Other secondary outcomes were not reported.The other RCT found no significant difference between autofluorescence- and tetracycline fluorescence-guided sequestrectomy for the surgical treatment of MRONJ at any timepoint (at one-year follow-up: RR 1.05; 95% CI 0.86 to 1.30; 34 participants included in the analysis; very low-quality evidence). Secondary outcomes were not reported.

AUTHORS' CONCLUSIONS

Prophylaxis of MRONJOne open-label RCT provided some evidence that dental examinations in three-month intervals and preventive treatments may be more effective than standard care for reducing the incidence of MRONJ in individuals taking intravenous bisphosphonates for advanced cancer. We assessed the certainty of the evidence to be low.There is insufficient evidence to either claim or refute a benefit of either of the interventions tested for prophylaxis of MRONJ (i.e. PRGF inserted into the postextraction alveolus during dental extractions, and wound closure by primary or secondary intention after dental extractions). Treatment of MRONJAvailable evidence is insufficient to either claim or refute a benefit for hyperbaric oxygen therapy as an adjunct to conventional therapy. There is also insufficient evidence to draw conclusions about autofluorescence-guided versus tetracycline fluorescence-guided bone surgery.

The use of the buccal fat pad flap for oral reconstruction

Many congenital and acquired defects occur in the maxillofacial area. The buccal fat pad flap (BFP) is a simple and reliable flap for the treatment of many of these defects because of its rich blood supply and location, which is close to the location of various intraoral defects. In this article, we have reviewed BFP and the associated anatomical background, surgical techniques, and clinical applications. The surgical procedure is simple and has shown a high success rate in various clinical applications (approximately 90%), including the closure of oroantral fistula, correction of congenital defect, treatment of jaw bone necrosis, and reconstruction of tumor defects. The control of etiologic factors, size of defect, anatomical location of defect, and general condition of patient could influence the prognosis after grafting. In conclusion, BFP is a reliable flap that can be applied to various clinical situations.

Surgical treatment vs. conservative treatment in intravenous bisphosphonate-related osteonecrosis of the jaws. Systematic review

Aims

To determine the success rates of the surgical and non-surgical treatments in the management of bisphosphonate-related osteonecrosis of the jaws (BRONJ).

Material and Methods

A systematic review of the literature was made. A PubMed Medline database search was performed in order to include clinical studies published in English,between2004 and 2014 with the following key-words: “BRONJ AND treatment” and “NOT osteoporosis”. The following data was gathered: authors, title, year of publication, aim of study, level of evidence, sample size, treatment performed, treatment outcomes and follow-up. Studies including more than 20 patients with at least 6 months of follow-up, and that specify the different treatment approaches and their outcomes were included. Systematic reviews were excluded.All studies were classified according to the SORT criteria (Strength of Recommendation Taxonomy).

Results

The initial electronic search yielded 169 papers, and 13 studies were added after a manual search (total of 182 studies). After analysing the title and abstract and removing duplicates, 31 full-texts were obtained. A total of 12 papers were finally included. Two were classified as level 3 evidence and 9 as level 2. The quality of the selected studies and the risk of bias were also reported.

Conclusions

Surgical treatments like sequestrectomy, surgical debridement and bone osteotomies provide successful treatment outcomes, with success rates ranging from 58 to 100%. Controlled randomized clinical trials with larger samples and longer follow-up are needed to support these findings.

Key words:BRONJ, treatment.

[Research progress on bisphosphonate-related osteonecrosis of the jaws]

Bisphosphonates (BPs), as potent drugs inhibiting bone resorption, have been widely used for treatment of several diseases. In recent years, dentists and oral and maxillofacial surgeons reported continuously increasing cases of bisphosphonate-related osteonecrosis of the jaws (BRONJ). This disease is clinically characterized by exposed bones, formation of sequestrum, pain, and halitosis. Provided that pathogenesis of BRONJ is unclear, effective treatments for this disease are currently unavailable. Thus, prevention plays an important role in the management of BRONJ. This review summarizes research progress on pathogenesis, risk factors, clinical characteristics, treatment, and prevention of this condition.

Medication-Related Osteonecrosis of the Jaw: New Insights into Molecular Mechanisms and Cellular Therapeutic Approaches

In recent years, medication-related osteonecrosis of the jaw (MRONJ) became an arising disease due to the important antiresorptive drug prescriptions to treat oncologic and osteoporotic patients, as well as the use of new antiangiogenic drugs such as VEGF antagonist. So far, MRONJ physiopathogenesis still remains unclear. Aiming to better understand MRONJ physiopathology, the first objective of this review would be to highlight major molecular mechanisms that are known to be involved in bone formation and remodeling. Recent development in MRONJ pharmacological treatments showed good results; however, those treatments are not curative and could have major side effects. In parallel to pharmacological treatments, MSC grafts appeared to be beneficial in the treatment of MRONJ, in multiple aspects: (1) recruitment and stimulation of local or regional endogenous cells to differentiate into osteoblasts and thus bone formation, (2) beneficial impact on bone remodeling, and (3) immune-modulatory properties that decrease inflammation. In this context, the second objective of this manuscript would be to summarize the molecular regulatory events controlling osteogenic differentiation, bone remodeling, and osteoimmunology and potential beneficial effects of MSC related to those aspects, in order to apprehend MRONJ and to develop new therapeutic approaches.

Hyperbaric oxygen therapy and osteonecrosis

Osteonecrosis of the jaw may be caused by radiation, medication, or infection. Optimal therapy requires a multimodal approach that combines surgery with adjuvant treatments. This review focuses on the use of adjunctive hyperbaric oxygen therapy for this condition. In addition to evidence regarding the basic and clinical science behind hyperbaric oxygen therapy, controversies in the field and economic implications are discussed.

The influence of geranylgeraniol on microvessel sprouting after bisphosphonate substitution in an in vitro 3D-angiogenesis assay

OBJECTIVES

Recent studies focused on angiogenesis in the pathophysiology of bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ) and identified geranylgeraniol (GGOH) as a feasible option for BP-ONJ therapy. This study investigated the influence of GGOH on microvessel sprouting after BP-incubation in vitro.

MATERIALS AND METHODS

Ten experimental set-ups were randomly designed in an in vitro 3D-angiogenesis assay. Two groups included HUVEC cell spheroids with and without (±) GGOH substitution as controls and eight groups pairwise contained either clodronate or the nitrogen-containing bisphosphonates (N-BP) ibandronate, pamidronate, and zoledronate ± GGOH. The size of the cell spheroids including the outbranching sprouts (SpS) as well as the density (SpD) and length of the sprouts (SpL) were analyzed by a grid system after 0, 24, 48, and 72 h.

RESULTS

For controls and NN-BP clodronate, no significant differences at any tested parameter and any point of measurement could be detected within the experimental set-ups ± GGOH (p each ≥0.05). For N-BP ibandronate, the experimental set-ups +GGOH showed a significantly increased SpS, SpD, and SpL after 48 and 72 h (p each ≤0.002) compared to the experimental set-ups -GGOH. For N-BPs pamidronate and zoledronate, the experimental set-ups + GGOH demonstrated a significantly increased SpS, SpD, and SpL after 24, 48, and 72 h (p each ≤0.001) compared to the experimental set-ups -GGOH.

CONCLUSIONS

The strong negative influence of N-BPs on microvessel sprouting could be significantly reversed by GGOH.

CLINICAL RELEVANCE

Since supportive therapeutic options for BP-ONJ are lacking, GGOH might be a promising substitute for BP-ONJ prevention and therapy.

Effect of hyperbaric oxygen therapy on tooth extraction sites in rats subjected to bisphosphonate therapy-histomorphometric and immunohistochemical analysis

OBJECTIVE

This study aimed to investigate the effect of hyperbaric oxygen therapy (HBOT) on tooth extraction sites in rats treated with bisphosphonate.

MATERIALS AND METHODS

Rats were treated with zoledronic acid, subjected to tooth extractions and allocated into groups: (1) 7 days of HBOT, (2) 14 days of HBOT, (3) 7-day control, and (4) 14-day control. The site of tooth extractions was analyzed by histomorphometry and immunohistochemistry.

RESULTS

On macroscopic analysis, HBOT did not significantly affect bone exposure volume either at 7 or 14 days. On hematoxylin and eosin (H&E) analysis, the 14-day HBOT group showed less non-vital bone compared to both controls and 7-day HBOT group. HBOT significantly lowered expression of vascular endothelial growth factor (VEGF), receptor activator NF-kB ligand (RANKL), bone morphogenetic protein-2 (BMP-2), and osteoprotegerin (OPG) at 7 days, compared to control, whereas at 14 days, there was no significant difference for these variables.

CONCLUSION

HBOT can reduce the amounts of non-vital bone microscopically detected in tooth extraction sites of rats subjected to bisphosphonate therapy. The effect seems to occur in a dose-dependent mode. Further studies are required to clarify the mechanisms accounting for this effect.

CLINICAL RELEVANCE

Treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been a challenging task, where the effectiveness of HBOT is controversial. This study reports important effects of HBOT on the maxillae of rats subjected to bisphosphonate treatment, making an important contribution to the knowledge about the applicability of HBOT in BRONJ.

Stage 3 Medication-Related Osteonecrosis of the Posterior Maxilla: Surgical Treatment Using a Pedicled Buccal Fat Pad Flap: Case Reports

PURPOSE

Stage 3 medication-related osteonecrosis of the jaw (MRONJ) sometimes requires surgical treatment for resolution of the pathology and, in many cases, leads to oroantral communication in the posterior maxilla. The buccal fat pad flap is considered the best surgical choice for closure of large oroantral communications because it provides primary closure and guarantees adequate bone protection with sufficient blood supply for an effective bone healing process.

MATERIALS AND METHODS

Five consecutive patients affected by stage 3 posterior maxillary MRONJ were treated with surgical removal of the necrotic bone and primary closure of the oroantral communication using a buccal fat pad flap.

RESULTS

In each case, the size of the flap was always sufficient to perfectly close the defect without tension. There were no postoperative complications and the average postoperative hospital stay was 3 ± 1 days. The patients were seen at monthly follow-ups; after 12 ± 4 months of follow-up, no problems were noted in the treated area.

CONCLUSION

Despite the limited number of cases, the results of this study suggest that, for stage 3 posterior maxilla MRONJ, managing the site with a pedicled buccal fat pad flap and primary closure might guarantee adequate bone protection with sufficient blood supply for an effective bone healing process.

Bisphosphonate-related osteonecrosis of jaw (BRONJ) in Japanese population: a case series of 13 patients at our clinic

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) affects quality of life and is an important problem for dentists. A Japanese position paper on BRONJ was published in 2010. The purpose of this study was to review clinical data on the treatment of BRONJ obtained at the Clinic of Oral and Maxillofacial Surgery, Tokyo Dental College, Chiba Hospital to further our understanding of this disease. A total of 13 patients (6 men and 7 women) were included. All the patients included in this study had received Bisphosphonate (BP) therapy and had BRONJ. Five of them (38.5%) had received oral BP therapy for osteoporosis, while the remaining 8 (61.5%) had received parenteral BP therapy for bone metastases from breast or prostate cancer. Osteoporosis patients were treated with risedronate or alendronate. Breast or prostate cancer patients were treated with zoledronate. Two patients with rheumatoid arthritis were treated with corticosteroid. Three patients had diabetes mellitus. Eleven patients were treated with antibiotics, while 5 underwent surgical treatment. Discontinuation of BP was recorded in 7 patients during dental treatment. Sequestration was observed in 6 patients during an 11-month follow-up. Eventually, healing and improvement of the oral mucosa were observed in 3 patients. The current standard treatment for BRONJ does not always provide good results. It is necessary to accumulate further clinical data to establish more effective treatment strategies for BRONJ.

The influence of geranylgeraniol on human oral keratinocytes after bisphosphonate treatment: An in vitro study

This in vitro study analyzed the influence of geranylgeraniol (GGOH) on human oral keratinocytes (HOK) after exposure to bisphosphonates. HOK were incubated with four different bisphosphonates (clodronate, ibandronate, pamidronate, zoledronate) in two experimental set-ups: with and without GGOH. MTT and PrestoBlue assays were used to analyze HOK cell viability. HOK migration ability was examined with Boyden and Scratch assays, and Tunel and ToxiLight assays were used to detect the HOK apoptosis rate. No significant differences between the experimental set-ups, with and without GGOH, could be found for clodronate (p each >0.3). For the nitrogen-containing bisphosphonates, negative effects could be shown in the experimental set-ups without GGOH in all assays. In the GGOH experimental set-ups, the levels of HOK cell viability were significantly increased (MTT: p each ≤0.001; PrestoBlue: p each ≤0.012). The HOK migration ability was also greater (Boyden: p each <0.001; Scratch: p each ≤0.015). Regarding the apoptosis rate, reduced numbers of apoptotic HOK in the Tunel assay (p each <0.001) and decreased adenylate kinase release in the ToxiLight assay (p each ≤0.002) were observed. GGOH reversed the negative effects of bisphosphonates on HOK. These findings provide evidence that GGOH could be a promising treatment option for BP-ONJ.

Bisphosphonate-related osteonecrosis of the jaw: specificities

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is a severe complication that has recently emerged in patients treated with intravenous bisphosphonates for malignant diseases. This complication usually presents after a minor local trauma during a dental treatment. Several etiopathogenic mechanisms of this pathological condition have been proposed, but no model can explain all morphological changes observed at the macroscopic and microscopic level. BRONJ is likely to be related to direct toxicity in the bone and soft tissue cells, due to nitrogen-containing bisphosphonates. This review elucidates the clinical indications and mechanism of action of bisphosphonates, reports some clinical diagnostic criteria for BRONJ, describe the histopathological criteria for BRONJ diagnosis, the potential triggering pathways and the available treatment strategies.

Bisphosphonate associated osteonecrosis of the jaw: an update on pathophysiology, risk factors, and treatment

Osteonecrosis of the jaw in patients treated with bisphosphonates is a relatively rare but well known complication at maxillofacial units around the world. It has been speculated that the medication, especially long-term i.v. bisphosphonate treatment, could cause sterile necrosis of the jaws. The aim of this narrative review of the literature was to elaborate on the pathological mechanisms behind the condition and also to gather an update on incidence, risk factors, and treatment of bisphosphonate associated osteonecrosis of the jaw. In total, ninety-one articles were reviewed. All were published in internationally recognized journals with referee systems. We can conclude that necrotic lesions in the jaw seem to be following upon exposure of bone, for example, after tooth extractions, while other interventions like implant placement do not increase the risk of osteonecrosis. Since exposure to the bacterial environment in the oral cavity seems essential for the development of necrotic lesions, we believe that the condition is in fact chronic osteomyelitis and should be treated accordingly.

Antiresorptive drug-related osteonecrosis of the jaw

Nitrogen-containing and non-nitrogen-containing bisphosphonates have been implicated in the development of osteonecrosis of the jaw (ONJ), a condition termed bisphosphonate-related OHJ. Other antiresorptive drugs have been implicated in the development of OHJ, hence the new term antiresorptive drug-related ONJ. The underlying pathogenesis remains unclear, and no definite diagnosis or cure has been established for this debilitating condition. This article reviews some of the most common antiresorptive drugs with their associated risks of ONJ and the current understanding of the pathogenesis ONJ, and summarizes current clinical guidelines.

Conservative surgical management of stage I bisphosphonate-related osteonecrosis of the jaw

Purpose. To report the efficacy of conservative surgical treatment for stage I bisphosphonate-related osteonecrosis of the jaw (BRONJ). Materials and Methods. This study reports the clinical outcomes of 63 patients treated for BRONJ stage I (according to Ruggiero's staging system) at the Oral Pathology and Laser-Assisted Surgery Unit of the University of Parma between January 2004 and January 2011. Surgical interventions were performed, under local analgesia, in patients unresponsive for a period of six months to noninvasive treatments such as cycles of local or systemic antibacterial therapy combined or not to low level laser therapy, ozone therapy, or Hyperbaric Oxygen Therapy. All interventions were performed after the consultation of oncologist or physician. Results. In our experience, conservative surgical treatment is associated with the highest number of BRONJ healed sites in stage I disease. Complete healing was observed in 92.6% of sites surgically treated. Conclusions. This study confirms that treatment of patients affected by minimal bone exposition, (stage I of BRONJ), through conservative surgical strategies, possibly with laser, may result in a high control of the disease in the long term.

Clinical management of suppurative osteomyelitis, bisphosphonate-related osteonecrosis, and osteoradionecrosis: report of three cases and review of the literature

In the past, osteomyelitis was frequent and characterized by a prolonged course, treatment response uncertainty, and occasional disfigurement. Today, the disease is less common; it is believed that the decline in prevalence may be attributed to increased availability of antibiotics and improvement of overall health patterns. Currently, more common osteomyelitis variants are seen, namely, osteoradionecrosis (ORN) and bisphosphonate-related osteonecrosis of the jaws (BRONJ). Osteomyelitis, ORN, and BRONJ can present with similar symptoms, signs, and radiographic findings. However, each condition is a separate entity, with different treatment approaches. Thus, accurate diagnosis is essential for adequate management and improved patient prognosis. The aim of this paper is to report three cases of inflammatory lesions of the jaws—osteomyelitis, ORN, and BRONJ—and to discuss their etiology, clinical aspects, radiographic findings, histopathological features, treatment options, and preventive measures.

Intraoperative efficiency of fluorescence imaging by Visually Enhanced Lesion Scope (VELscope) in patients with bisphosphonate related osteonecrosis of the jaw (BRONJ)

OBJECTIVES

The purpose of this study was to determine the potential of tissue fluorescence imaging by using Visually Enhanced Lesion Scope (VELscope) for the detection of osteonecrosis of the jaw induced by bisphosphonates (BRONJ).

METHODS

We investigated 20 patients (11 females and 9 males; mean age 74 years, standard deviation ± 6.4 years), over a period of 18 month with the diagnosis of BRONJ in this prospective cohort study. All patients received doxycycline as a fluorescending marker for osseous structures. VELscope has been used intraoperatively using the loss of fluorescence to detect presence of osteonecrosis. Osseous biopsies were taken to confirm definite histopathological diagnosis of BRONJ in each case.

RESULTS

Diagnosis of BRONJ was confirmed for every patient. In all patients except one, VELscope was sufficient to differentiate between healthy and necrotic bone by visual fluorescence retention (VFR) and visual fluorescence loss (VFL). 19 cases out of a total of 20 showed no signs of recurrence of BRONJ during follow-up (mean 12 months, range 4-18 months).

CONCLUSION

VELscope examination is a suitable tool to visualize necrotic areas of the bone in patients with bisphosphonate related osteonecrosis of the jaw. Loss of fluorescence in necrotic bone areas is useful intraoperatively as a tool for fluorescence-guided bone resection with relevant clinical interpretation.

Oral care and the use of bone-targeted agents in patients with metastatic cancers: A practical guide for dental surgeons and oncologists

BACKGROUND

Bone-targeted agents such as bisphosphonates and the RANKL antibody have revolutionised the care of patients with bone metastases. There has, however been increasing concern about the oral health of these patients and in particular osteonecrosis of the jaw (ONJ), especially with the increasing use of these agents at higher potencies for greater periods of time.

METHODS

A review of the published data in PubMed and meeting abstracts was performed to examine incidence, risk factors, pathogenesis, clinical course and management of osteonecrosis of the jaw with focus on cancer patients treated with bone-targeted agents (BTA) for bone metastases. This manuscript takes the most frequent and pertinent questions raised by oncologists, dentists and oral and maxillofacial surgeons and tries to give a pragmatic overview of the literature.

RESULTS

The incidence of ONJ varies depending on types of bone-targeted agents, duration of treatment and additional risk factors. The causes and pathogenesis of ONJ is not fully elucidated, however bone-targeted therapy induced impaired bone remodelling, microtrauma secondary to jaw activity, and oral bacterial infection seem to be important factors. Since the treatment options for ONJ are limited and not well established, preventive strategies have to be included in patients management.

CONCLUSIONS

Many unanswered questions remain about the optimal oral care of patients receiving bone-targeted agents. Prospective data collection will remedy this and help to provide practical guidelines for the management and treatment of those patients that require dental intervention.

Comprehensive review of hyperbaric oxygen therapy

Hyperbaric oxygen therapy involves inspiration of pure high pressure oxygen. For the past 20 years, administration of 100% high pressure oxygen and its potential benefits in management of diseases have been more clarified. Physiological advantages advocate HBO for the first-line treatment of several conditions. The specialty of craniofacial surgery is broad and deals with a diverse range of complications. The goal of this review is to help surgeons in their treatment planning by categorizing the indications of HBO therapy for oral and maxillofacial surgery. We also assess research data substantiating these indications where we believe basic physiological mechanisms and clinical evidences support further investigation on HBO efficacy to greater understanding of its potential benefit in oral and maxillofacial surgery.