Bisphosphonates-related osteonecrosis of the jaws: a concise review of the literature and a report of a single-centre experience with 151 patients

The effectiveness of autologous platelet concentrates in prevention and treatment of medication-related osteonecrosis of the jaws: A systematic review

The systematic review aims to answer the PICOS question: "Are the autologous platelet concentrates (APCs) an effective strategy in prevention and/or treatment of patients at risk of/affected by medication-related osteonecrosis of the jaws (MRONJ)?". A literature search was conducted via PubMed, MEDLINE, EMBASE, and CINAHL (January 2006 - September 2023). 30 articles were included, evaluating preventive (n = 8*) and treatment strategies (n = 23*). The risk of bias and quality of studies were assessed utilising ROB-2, ROBIN-1 and GRADE criteria. Meta-analysis was undertaken for eligible studies. The application of APCs demonstrated a statistically significant effectiveness in prevention of MRONJ in 86.13% (p < 0.001) but failed to achieve the same level of certainty in treatment of established MRONJ in 83.4% (p = 0.08). High levels of bias were identified; thus, the results should be interpreted with caution. More high quality prospective randomised controlled trials are needed to further evaluate the effectiveness of APCs in management of MRONJ.

Drug holiday of high-dose denosumab and recovery from osteoclast inhibition using immunohistochemical investigation of 7 patients with medication-related osteonecrosis of the jaw undergoing segmental mandibulectomy

Background/purpose

Denosumab is used to treat bone metastases from malignant tumors. Unlike bisphosphonates, denosumab is not deposited in the bone; thus, withdrawal for a relatively short period would help recovery from osteoclast suppression. This study investigated the relationship between drug holidays and recovery from osteoclast suppression.

Materials and methods

Seven patients who received high-dose denosumab and underwent segmental mandibulectomy for medication-related osteonecrosis of the jaw were enrolled in this study. Osteoclast suppression (+) was defined as the absence of cathepsin K-positive cells or cathepsin K-positive mononuclear or small multinucleated cells observed on the bone surface of both mesial and distal specimens. When normal osteoclasts were found, osteoclast suppression was defined as (-); when both suppressed cathepsin K-positive cells and normal morphological osteoclasts were found, it was defined as (±).

Results

Osteoclast suppression was: (+) in four patients, three without a drug holiday and one with a 9-month drug holiday; (±) in one patient with an 8-month drug holiday, and (-) in two patients with drug holidays for 13 and 20 months.

Conclusion

These findings suggest that a long-term drug holiday, such as 12 months, is required for recovery from osteoclast suppression in patients with cancer receiving high-dose denosumab.

Effect of Low-level Light Therapy on Post-operative Healing of Secondary Chronic Osteomyelitis of the Jaws - A Prospective Study

Introduction

Osteomyelitis of the jaws is a common disease of the maxillofacial region. The goal of treatment is to alleviate pain, reduce infection, inhibit the progression of the disease and induce bone and mucosal healing. In addition to surgical management and antibiotic and oxygen hyperbaric therapy, new therapeutic strategies for the treatment of osteomyelitis are developed. One of the novel approaches is photobiomodulation therapy or low-level light therapy (LLLT).

Materials and Methods

After surgical treatment, experimental group patients (n = 4) were treated with LLLT for five sessions with an extraoral pulsed 635-nm LED lamp (Repuls7, Repuls Lichtmedizintechnik GmbH, Austria), maximum output power: 140 mW/cm2, frequency: 2.5 Hz, duty cycle: 50%. Clinical achievement and patient pain perception (through Visual Analogue Scale score) were evaluated at 1-, 3- and 6-month follow-up appointments and compared with control group (n = 4) patients, treated with standard therapy.

Results

At three and six months, clinical achievement was better in patients treated with LLLT. Pain and discomfort resolution was significantly greater in the experimental group.

Discussion

Taking into consideration the results of this study, it can be concluded that LLLT shows potential for improving clinical outcome of surgical and medical treatment of secondary chronic osteomyelitis of the jaws. Furthermore, pain and discomfort were significantly reduced in patients treated with LLLT. Further research with a larger sample size is needed to obtain a more accurate insight into this promising field.

Efficacy of Adjunctive Photobiomodulation in the Management of Medication-Related Osteonecrosis of the Jaw: A Systematic Review

Background: Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse medication response that manifests as progressive bone necrosis in the craniofacial area. There is still no clear treatment protocol for the management of MRONJ. The purpose of this study was to conduct a systematic review to assess the efficacy of photobiomodulation (PBM) as an adjunct to MRONJ therapy. Methods: In line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, a literature search was performed on PubMed/MEDLINE, Scopus, Web of Science, and Cochrane databases. Two examiners examined eligibility and risk of bias separately before extracting data. Results: Two hundred sixty-nine articles were found through electronic search, out of which only 11 met the inclusion criteria and were included in qualitative synthesis (9 retrospectives, 1 prospective, and 1 case series). A total number of 759 patients and a mean age ranging from 54 to 74 years were reviewed. Females were the most frequent gender in all of the selected studies (72% females to 28% males), and the most frequent stage in the studies mentioned above was stage II (66%). Most of the studies had shown a significant improvement when PBM was used as an adjunctive treatment. Conclusions: Based on the results of this study, PBM as an adjuvant therapy can significantly improve the outcomes of each treatment plan. However, surgical intervention for the complete healing of the lesions is suggested.

Photobiomodulation therapy in management of cancer therapy-induced side effects: WALT position paper 2022

Disclaimer

This article is based on recommendations from the 12th WALT Congress, Nice, October 3-6, 2018, and a follow-up review of the existing data and the clinical observations of an international multidisciplinary panel of clinicians and researchers with expertise in the area of supportive care in cancer and/or PBM clinical application and dosimetry. This article is informational in nature. As with all clinical materials, this paper should be used with a clear understanding that continued research and practice could result in new insights and recommendations. The review reflects the collective opinion and, as such, does not necessarily represent the opinion of any individual author. In no event shall the authors be liable for any decision made or action taken in reliance on the proposed protocols.

Objective

This position paper reviews the potential prophylactic and therapeutic effects of photobiomodulation (PBM) on side effects of cancer therapy, including chemotherapy (CT), radiation therapy (RT), and hematopoietic stem cell transplantation (HSCT).

Background

There is a considerable body of evidence supporting the efficacy of PBM for preventing oral mucositis (OM) in patients undergoing RT for head and neck cancer (HNC), CT, or HSCT. This could enhance patients’ quality of life, adherence to the prescribed cancer therapy, and treatment outcomes while reducing the cost of cancer care.

Methods

A literature review on PBM effectiveness and dosimetry considerations for managing certain complications of cancer therapy were conducted. A systematic review was conducted when numerous randomized controlled trials were available. Results were presented and discussed at an international consensus meeting at the World Association of photobiomoduLation Therapy (WALT) meeting in 2018 that included world expert oncologists, radiation oncologists, oral oncologists, and oral medicine professionals, physicists, engineers, and oncology researchers. The potential mechanism of action of PBM and evidence of PBM efficacy through reported outcomes for individual indications were assessed.

Results

There is a large body of evidence demonstrating the efficacy of PBM for preventing OM in certain cancer patient populations, as recently outlined by the Multinational Association for Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO). Building on these, the WALT group outlines evidence and prescribed PBM treatment parameters for prophylactic and therapeutic use in supportive care for radiodermatitis, dysphagia, xerostomia, dysgeusia, trismus, mucosal and bone necrosis, lymphedema, hand-foot syndrome, alopecia, oral and dermatologic chronic graft-versus-host disease, voice/speech alterations, peripheral neuropathy, and late fibrosis amongst cancer survivors.

Conclusions

There is robust evidence for using PBM to prevent and treat a broad range of complications in cancer care. Specific clinical practice guidelines or evidence-based expert consensus recommendations are provided. These recommendations are aimed at improving the clinical utilization of PBM therapy in supportive cancer care and promoting research in this field. It is anticipated these guidelines will be revised periodically.

Relationship between drug holiday of the antiresorptive agents and surgical outcome of medication-related osteonecrosis of the jaw in osteoporosis patients

A drug holiday of 3 months does not promote separation of sequestra and is not correlated with treatment outcomes after surgical therapy in osteoporosis patients who receive antiresorptive agents and who have medication-related osteonecrosis of the jaw. Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse effect of antiresorptive agents alone or in combination with immune modulators or antiangiogenic medications, in the absence of radiation exposure to the head and neck region. The effectiveness of surgical treatment for MRONJ has been reported, but the timing of the operation remains controversial. The purpose of this study was to clarify whether preoperative drug holidays of antiresorptive agents promote sequestrum separation and improve treatment outcomes in patients who receive low doses of antiresorptive agents. This retrospective study included 173 patients who received low-dose antiresorptive agents and underwent surgical therapy. The effects of a drug holiday on the separation of sequestra and treatment outcomes were analyzed using logistic and Cox regression analyses. Multivariate analysis revealed that administration of an antiresorptive agent for more than 4 years, a high number of lymphocytes, and an extensive osteolytic area were significantly correlated with separation of sequestra, but drug holiday did not promote sequestrum separation. Furthermore, a drug holiday of 90, 120 or 180 days did not show any improvement in treatment outcomes. The drug holiday of the antiresorptive agents for the treatment of MRONJ is unnecessary, and surgical therapy should be performed early.

Factors Exacerbating Clinical Symptoms and CT Findings in Patients with Medication-Related Osteonecrosis of the Jaw Receiving Conservative Therapy: A Multicenter Retrospective Study of 53 Cases

Recent reports have shown that better treatment outcomes are obtained with surgical therapy in patients with medication-related osteonecrosis of the jaw (MRONJ) than with conservative therapy. However, conservative treatment is selected due to factors such as old age and poor general condition. Conservative therapy aims to relieve symptoms and prevent lesion exacerbation; however, the lesion may expand rapidly in some cases. This study investigated the clinical and imaging findings of 53 MRONJ patients undergoing conservative therapy, and the changes in the clinical findings and the lesion enlargement on CT imaging were examined. Improved clinical findings and no worsening of the imaging findings were considered overall comprehensive treatment successes. Among the 53 patients, the clinical symptoms disappeared or improved in 15 patients, whereas they worsened in 6. In contrast, osteolytic lesion enlargement occurred in 17 patients. The comprehensive treatment outcome of conservative therapy was successful in 12 patients and unsuccessful in 41 patients. The periosteal reaction was significantly correlated with poor comprehensive treatment outcomes (p = 0.038). MRONJ lesions may advance, even if they appear to improve clinically while undergoing conservative treatments. Patients, especially those with periosteal reactions, must be closely followed up with CT examinations, regardless of the clinical findings.

Retrospective Analysis of Treatment Outcomes of Maxillary Sinusitis Associated with Medication-Related Osteonecrosis of the Jaw

Although maxillary sinusitis often occurs in patients with medication-related osteonecrosis of the jaw (MRONJ) of the upper jaw, there have been few reports on the treatment and outcomes for maxillary sinusitis associated with maxillary MRONJ. This study aimed to retrospectively investigate the treatment outcomes of maxillary sinusitis in patients with MRONJ of the upper jaw. There were 34 patients diagnosed with maxillary MRONJ and sinusitis by preoperative computed tomography who underwent surgery in our institution between January 2011 and December 2019. Age, sex, primary disease, stage of MRONJ, class and administration period of an antiresorptive agent, corticosteroid administration, preoperative leukocyte count and serum albumin level, periosteal reaction, sinusitis grade, maxillary sinus surgical procedure, and treatment outcomes of MRONJ and sinusitis were examined. There were 7 male and 27 female patients (average age, 74.7 years). Complete healing of MRONJ was obtained in 29 of 34 patients (85.3%). Maxillary sinusitis resolved or improved in 21 patients (61.8%) but did not change or worsen in 13 patients (38.2%). We found that complete resection of necrotic bone with intraoperative irrigation of the maxillary sinus may provide good treatment outcomes for maxillary sinusitis associated with MRONJ, although our findings were not statistically significant owing to the small number of patients.

Osteonecrosis of the Jaw and Antiresorptive Agents in Benign and Malignant Diseases: A Critical Review Organized by the ECTS

CONTEXT

Antiresorptive therapy significantly reduces fracture risk in patients with benign bone disease and skeletal-related events (SREs) in patients with bone metastases (BM). Osteonecrosis of the jaw (ONJ) is a rare but severe condition manifested as necrotic bone lesion or lesions of the jaws. ONJ has been linked to the use of potent antiresorptive agents, termed medication-related ONJ (MRONJ).

OBJECTIVE

We aimed to identify the differences various aspects of MRONJ among distinct patient categories and provide recommendations on how to mitigate the risk and optimally manage MRONJ in each of them.

METHODS

A working group of the European Calcified Tissue Society (ECTS) and 2 experts performed an updated detailed review of existing literature on MRONJ incidence, characteristics, and treatment applied in bone diseases with variable severity of skeletal insult, ranging from osteoporosis to prevention of cancer treatment-induced bone loss and SREs in cancer patients with BM.

RESULTS

The risk for MRONJ is much higher in patients with advanced malignancies compared to those with benign bone diseases because of the higher doses and more frequent administration of antiresorptive agents in individuals with compromised general health, along with coadministration of other medications that predispose to MRONJ. The overall risk for MRONJ is considerably lower than the benefits in all categories of patients.

CONCLUSION

The risk for MRONJ largely depends on the underlying bone disease and the relevant antiresorptive regimen applied. Physicians and dentists should keep in mind that the benefits of antiresorptive therapy far outweigh the risk for MRONJ development.

Medication Related Osteonecrosis of the Jaw: 2021 Position Statement of the Korean Society for Bone and Mineral Research and the Korean Association of Oral and Maxillofacial Surgeons

Antiresorptives are the most widely prescribed drugs for the treatment of osteoporosis. They are also used in malignant bone metastases, multiple myeloma, and Paget's disease, and provide therapeutic efficacy on those diseases. However, it was reported that the occurrence of osteonecrosis of the jaw (ONJ) could be related to antiresorptive exposures, and there have been many cases regarding this issue. Therefore, a clearer definition and treatment guidelines were needed for this disease. The American Society for Bone and Mineral Research and the Amnerican Association of Oral and Maxillofacial Surgeons reported statements on bisphosphonate-related ONJ (BRONJ), and a revised version was recently presented. In the revised edition, the diagnosis BRONJ was changed to medication-related ONJ (MRONJ), which reflects consideration of the fact that ONJ also occurs for denosumab, a bone resorption inhibitor of the receptor activator of the nuclear factor-κB ligand antibody family, and bevacizumab, an anti-angiogenesis inhibitor. The Korean Society for Bone and Mineral Research and the Korean Association of Oral and Maxillofacial Surgeons had collectively formed a task force for the preparation of an official statement on MRONJ based on a previous position paper in 2015. The task force reviewed current knowledge and coordinated dental and medical opinions to propose the guideline customized for the local Korean situation.

The Treatment of Medication-Related Osteonecrosis of the Jaw (MRONJ): A Systematic Review with a Pooled Analysis of Only Surgery versus Combined Protocols

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse reaction of antiresorptive and antiangiogenic agents, and it is also a potentially painful and debilitating condition. To date, no specific studies have prospectively evaluated the efficacy of its treatment and no robust standard of care has been established. Therefore, a systematic review (2007–2020) with a pooled analysis was performed in order to compare MRONJ surgical techniques (conservative or aggressive) versus combined surgical procedures (surgery plus a non-invasive procedure), where 1137 patients were included in the pooled analysis. A statistically significant difference in the 6-month improvement rate, comparing combined conservative surgery versus only aggressive (91% versus 72%, p = 0.05), was observed. No significant difference regarding any group with respect to the 6-month total resolution rate (82% versus 72%) was demonstrated. Of note, conservative surgery combined with various, adjuvant, non-invasive procedures (ozone, LLLT or blood component + Nd:YAG) was found to achieve partial or full healing in all stages, with improved results and the amelioration of many variables. In conclusion, specific adjuvant treatments associated with minimally conservative surgery can be considered effective and safe in the treatment of MRONJ, although well-controlled studies are a requisite in arriving at definitive statements

Treatment of Stage 2 Medication-Induced Osteonecrosis of the Jaw: A Case Series

Medication-induced jaw osteonecrosis (MRONJ) is a rare and serious disease with a negative impact on patients’ quality of life, whose exact cause remains unclear and which may have a multifactorial origin. Although there are different therapeutic protocols, there is still no consensus. This case series evaluated three patients diagnosed with staged 2 MRONJ treated at the University of Murcia dental clinic according to the protocols described by the Spanish Society of Oral and Maxillofacial Surgery and the American Association of Oral and Maxillofacial Surgeons. Within 12 months of the application of therapeutic protocols, the lesions were completely healed in all cases. Radiography showed slow but progressive healing with normal bone structure. Conservative treatment with antibiotics, chlorhexidine rinses and minimally invasive surgical intervention with necrotic bone resection is effective in treating stage 2 of MRONJ. In cases of refractory osteonecrosis, the application of platelet and leukocyte-rich fibrin (PRF-L) in the surgical approach improves the outcome in soft tissue healing and bone regeneration but further research is needed to confirm its effectiveness.

Adjuvant therapies for MRONJ: A systematic review

OBJECTIVE

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction caused by the use of antiresorptive antiangiogenic medication. Treating MRONJ is difficult and besides standard treatments, which are conservative medical and surgical approaches, there are some adjuvant therapies that might further stimulate healing. The aim of this systematic review is to compare outcome and effectiveness of currently available adjuvant therapies for MRONJ.

METHODS

This systematic review was conducted following the PRISMA guidelines. Articles focusing on mucosal healing in patients treated with an adjuvant therapy for MRONJ were selected and analysed. Inclusion was not limited to randomized controlled trials to present a complete review of the current literature.

RESULTS

A search was performed in Pubmed, Embase, Web of Science and Cochrane Central Register of Controlled Trials. Thirty articles out of 3297 were included. Laser ablation had a success of 60-95% for complete healing. The controlled trials of leukocyte- and platelet-rich-fibrine (LPRF) showed 60-100% success for the same outcome. Fluorescence guided surgery had a complete healing percentage of 85-90%.

CONCLUSIONS

The results suggest that laser ablation, LPRF and fluorescence guided surgery might have a potential in improving the healing process. Interpreting the results should however be done with great care and a critical point of view, as most articles had a medium to high risk of bias. More randomized controlled trials are necessary to define the most beneficial therapy protocols.

CLINICAL RELEVANCE

It seems that adjuvant surgical therapies for treating MRONJ are beneficial for mucosal healing, but there is only low scientific evidence.

Surgical Treatment of Medication-Related Osteonecrosis of the Jaw: A Retrospective Study

The purpose of this study was to confirm the success rate of surgical treatment of medication-related osteonecrosis of the jaw (MRONJ) in patients at a single institution (Association of Oral and Maxillofacial Surgery (AAOMS) stages 1, 2, or 3), and to identify the factors that influence treatment outcomes. As a result of analyzing the outcomes of treatment, surgical "success" was achieved in 93.97% (109) of cases, and "failure" was observed at 6.03% (7) cases. Analysis of patient factors that potentially affect treatment outcomes showed that zoledronate dose (p = 0.005) and the IV (intravenous) injection of drugs (p = 0.044) had significant negative impacts.

Medication-Related Osteonecrosis of the Jaws

Medication-related osteonecrosis of the jaw is an oral complication in cancer patients being treated with either antiresorptive or antiangiogenic drugs. The first reports of MRONJ were published in 2003. Hundreds of manuscripts have been published in the medical and dental literature describing the complication, clinical and radiographic signs and symptoms, possible pathophysiology, and management. Despite this extensive literature, the pathobiological mechanisms by which medication-related osteonecrosis of the jaw develops have not yet been fully delineated. The aim of this manuscript is to present current knowledge about the complication ragarding to the definition, known risk factors, and clinical management recommendations. Based on this current state of the science, we also propose research directions that have potential to enhance the management of future oncology patients who are receiving these agents.

Can Surgical Management Improve Resolution of Medication-Related Osteonecrosis of the Jaw at Early Stages? A Prospective Cohort Study

PURPOSE

There is no clarity on which protocol is proper to use in the management of medication-related osteonecrosis of the jaw (MRONJ) at early stages (ie, stages 1 and 2) to halt disease progression. The aim of this study was to evaluate the success of surgical treatment in terms of time to mucosal integrity and downstaging in patients with MRONJ at early stages.

MATERIALS AND METHODS

The study was implemented as a prospective, single-center cohort study. The sample included patients who presented at Magna Graecia University of Catanzaro with a clinical diagnosis of MRONJ and underwent surgical treatment. The primary predictor variables were gender, age, medical history, drug administration, MRONJ localization, trigger factors, and stage. The outcome variables were 1) time to mucosal integrity after surgery with time-to-event analysis and 2) time to downstaging of MRONJ lesions. Descriptive, bivariate, and regression statistics were performed.

RESULTS

The study sample included 129 MRONJ patients (90 women and 39 men; mean age, 71.2 ± 12.7 years), of whom 57 had stage 1 and 72 had stage 2. The mean time to achieve mucosal integrity was 71.6 ± 67.7 days, considering the survival probability always to be 93% or greater. The mean time to achieve downstaging of the lesion was 43.6 ± 38.4 days. Patients older than 70 years, those affected by osteometabolic disorders, and those treated with oral antiresorptive therapy showed a significantly shorter time to mucosal healing and downstaging (P < .05). In patients with stage 2 MRONJ, we recorded a significantly longer time to mucosal integrity (56.4 ± 54.5 days) but shorter time to lesion downstaging (33.6 ± 9.9 days) than in patients with stage 1 MRONJ (P < .05).

CONCLUSIONS

Surgical treatment of patients in the early stages of MRONJ guarantees benefits in outcomes such as mucosal integrity and lesion downstaging, improvement in quality of life, and faster reuptake of medication therapy, especially for oncologic patients.

Laser surgery in management of medication-related osteonecrosis of the jaws: a meta-analysis

PURPOSE

The aim of this study was to perform a systematic review and meta-analysis to evaluate the efficacy of laser therapy on medication-related osteonecrosis of the jaw (MRONJ) treatment.

METHODS

This study followed PRISMA standards, and an electronic search was performed on the PubMed/MEDLINE, Scopus, and Cochrane databases. Eighty-nine articles were found. After reading the manuscripts, 15 articles remained for the review. Three of them were selected for meta-analysis.

RESULTS

Female gender was predominant (72.5%), and mean age was 66.5 years. Follow-up varied between 3 and 80 months, and the most used bisphosphonate was zoledronic acid (71.6%). Stage II of MRONJ was the most prevalent (68.9%), and the mandible was the most affected site (64.5%). Qualitative data showed that treatment with laser surgery (Er:YAG) was most effective regarding complete healing of the lesion (90%) compared with other treatments. Meta-analysis data showed that low-level laser therapy (LLLT) was more effective than medical treatment (P = 0.006), and surgical treatment was more effective than LLLT (P = 0.008).

CONCLUSION

Laser surgery was significantly superior to LLLT (p < 0.00001). Therefore, laser surgical therapy seems to be a great management strategy for MRONJ treatment from stage II. LLLT was shown to improve conservative management in earlier MRONJ stages.

Pharmacoepidemiology and clinical characteristics of medication-related osteonecrosis of the jaw

Background

The aim of this study was to investigate clinical and pharmacoepidemiologic characteristics of medication-related osteonecrosis of the jaw.

Methods

The study population is comprised of 86patients who were diagnosed with ONJ at Ewha Womans University Mokdong Hospital from 2008 to 2015. Factors for epidemiologic evaluation were gender, age, location of lesion, and clinical history. The types of bisphosphonates, duration of intake, and the amount of accumulated dose were evaluated for therapeutic response. Clinical symptoms and radiographic images were utilized for the assessment of prognosis.

Results

Among the 86 patients, five were male, whereas 81 were female with mean age of 73.98 (range 45-97). Location of the lesion was in the mandible for 58 patients and maxilla in 25 patients. Three patients had both mandible and maxilla affected. This shows that the mandible is more prone to the formation of ONJ lesions compared to the maxilla. ONJ occurred in 38 cases after extraction, nine cases after implant surgery, six cases were denture use, and spontaneously in 33 cases. Seventy-six patients were taking other drugs aside from drugs indicated for osteoporosis. Most of these patients were diagnosed as osteoporosis, rheumatic arthritis, multiple myeloma, or had a history of cancer therapy. Higher weighted total accumulation doses were significantly associated with poorer prognosis (P < 0.05).

Conclusion

Dose, duration, route, and relative potency of bisphosphonates are significantly associated with treatment prognosis of osteonecrosis of the jaw.

Severe Case of Osteonecrosis Following Implant Placement in a Patient in Therapy With Bisphosphonates: A Case Report

Osteonecrosis of the jaw is a rare complication that has been associated with the use of bisphosphonates. A 77-year-old patient presented in April 2013 asking for a consultation. She reported that in May 2009, she underwent an implant rehabilitation with 8 implants and an immediately loaded fixed prosthesis in the maxilla. After a few months the patient started to report pain and purulent secretions that were neglected by the clinician for several years. She decided to refer to the Dental Clinic after another acute pain episode. Once the fixed prosthesis was removed, exposed necrotic bone was found in relation to the implants. The patient reported having taken oral alendronic acid to treat osteoporosis since before 2006. The patient underwent a functional endoscopic sinus surgery and a removal of necrotic bone blocks. Three years of follow-up showed healed tissues with no recurrence, although the alveolar crest appeared irregular on radiographs.

Medication-related osteonecrosis of the jaw: Surgical or non-surgical treatment?

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (bisphosphonates and denosumab) and anti-angiogenic therapy used in the management of oncologic and, less frequently, osteoporotic patients. While there is good international agreement on the diagnostic and staging criteria of MRONJ and the cessation of antiresorptive/anti-angiogenic treatments, the gold standard of treatment is still controversial, in particular between non-surgical and surgical approaches. The former usually includes antiseptic mouth rinse, cyclic antibiotic therapy, low-level laser therapy and periodic dental checks; the latter consists of surgical necrotic bone removal. The purpose of this retrospective study was to describe the therapeutic approaches and outcomes of 131 lesions from 106 MRONJ patients treated at the Policlinic of Bari. Non-surgical treatments were chosen for 24 lesions that occurred in 21 patients who, due to comorbidities and/or the impossibility of stopping oncologic therapies, could not undergo surgical treatment. As to the outcome, all the surgically treated lesions (107) showed complete healing, with the exception of 13.5% of the lesions, all of which were stage III, which did not completely heal but showed reduction to stage I. The 24 non-surgically treated lesions never completely healed and, rather, generally remained stable. Only two cases exhibited a reduction in staging. Based on our observations, MRONJ occurring both in neoplastic and non-neoplastic patients benefits more from a surgical treatment approach, whenever deemed possible, as non-surgical treatments do not seem to allow complete healing of the lesions.

Factors affecting development of medication-related osteonecrosis of the jaw in cancer patients receiving high-dose bisphosphonate or denosumab therapy: Is tooth extraction a risk factor?

Methods for preventing medication-related osteonecrosis of the jaw (MRONJ) in cancer patients who have received high-dose bisphosphonate (BP) or denosumab (Dmab) have not yet been established. Tooth extraction after starting medication has been believed to be a major risk factor for MRONJ, and therefore this procedure tends to be avoided. This study investigated the risk factors for MRONJ, with a special reference to the correlation between tooth extraction and development of MRONJ. One hundred and thirty-five cancer patients who were administrated high-dose BP or Dmab were enrolled in the study. Demographic factors, general condition, treatment factors, and dental findings were examined retrospectively using medical records and panoramic X-ray findings. The cumulative occurrence rate of MRONJ was calculated using the Kaplan–Meier method, and the correlation between these variables and development of MRONJ was analyzed by univariate and multivariate Cox regression analysis. MRONJ developed in 18 of 135 patients. The 1-, 2-, and 3-year cumulative occurrence rates were 8.6%, 21.5%, and 29.2%, respectively. The duration of medication before first visit to the dental unit and the presence of a tooth with clinical symptoms were significantly correlated with the development of MRONJ. The rate of MRONJ occurrence in patients who had teeth with clinical symptoms, but who did not undergo tooth extraction, became higher 2 years later than that in patients who underwent extraction of teeth with symptoms, although not significant. Early dental examination and effective preventative care to avoid infection/inflammation are important for preventing MRONJ.

Combined Approach to Treat Medication-Related Osteonecrosis of the Jaws

Introduction: The proper therapeutic plan for medication-related osteonecrosis of the Jaw (MRONJ) is still lacking long-term data up to today. They were several high-technological appliances proposed for the different intervention steps, in addition to tissue repair promoters. The reason for proposing an integrated technique is justified, beyond better compliance of the patients associated to the pain and inflammation reduction and bleeding control, there is also achieving better hard and soft tissues healing. Methods: Patients diagnosed with bisphosphonates-related osteonecrosis of the jaws (BRONJ) at the Odontostomatology and Maxillo-Facial Surgery Unit of the Hospital of Piacenza undergone surgical intervention. The intervention was performed by using different devices: Piezosurgery for removing the necrotic bone tissue and for obtaining the bone specimen essential for histological analysis; Er:YAG laser (2940 nm) to vaporize necrotic hard tissue until reaching the bleeding bone; platelet-rich plasma (PRP) to stimulate hard and soft tissue healing; and finally diode laser (808 nm) to perform a biostimulation of the surgical site. Results: All treated patients demonstrated a good postoperative comfort even without using painkillers, no bleeding, and a fast healing process. Most of the patients (92.85%) reached complete healing with a minimum follow up at 6 months. Histological exams demonstrated a good quality without artifacts. Conclusion: Sequential utilization of different high-technologies devices during all the steps of MRONJ treatment allows to perform a faster and less invasive surgery with a more comfortable postoperative healing process and it may represent a new and original approach for treating this severe adverse event.

Zoledronate suppresses VEGF‑induced capillary tube formation and inhibits expression of interferon‑induced transmembrane protein‑1 in human umbilical vein endothelial cells

Interferon‑induced transmembrane protein 1 (IFITM1) is a member of the interferon‑induced transmembrane protein family and has recently been identified as a novel protein participant in angiogenesis. Zoledronate (ZON), a nitrogen‑containing bisphosphonate, is widely used in the treatment of osteoporosis and to prevent bone metastases of certain cancer types. However, the association between ZON and IFITM1 has remained elusive. The present study investigated the effect of ZON on the expression of IFITM1 during vascular endothelial growth factor (VEGF)‑induced capillary tube formation in human umbilical vein endothelial cells. It was observed that cell proliferation and VEGF‑induced tube formation were significantly inhibited by treatment with 10 µM ZON. The expression of IFITM1 increased during VEGF‑induced tube formation. However, the VEGF‑induced increase in IFITM1 expression exhibited a dose‑ and time‑dependent decrease with ZON treatment at the mRNA and protein level. Furthermore, matrix metalloproteinase‑9 activation was markedly decreased by ZON treatment. These results suggest that induction of IFITM1 expression may be involved in the anti‑angiogenic activity of ZON.

Bisphosphonates in multiple myeloma: an updated network meta-analysis

BACKGROUND

Bisphosphonates are specific inhibitors of osteoclastic activity and are used in the treatment of patients with multiple myeloma (MM). While bisphosphonates are shown to be effective in reducing vertebral fractures and pain, their role in improving overall survival (OS) remains unclear. This is an update of a Cochrane review first published in 2002 and previously updated in 2010 and 2012.

OBJECTIVES

To assess the evidence related to benefits and harms associated with use of various types of bisphosphonates (aminobisphosphonates versus non-aminobisphosphonates) in the management of patients with MM. Our primary objective was to determine whether adding bisphosphonates to standard therapy in MM improves OS and progression-free survival (PFS), and decreases skeletal-related morbidity. Our secondary objectives were to determine the effects of bisphosphonates on pain, quality of life, incidence of hypercalcemia, incidence of bisphosphonate-related gastrointestinal toxicities, osteonecrosis of jaw (ONJ) and hypocalcemia.

SEARCH METHODS

We searched MEDLINE, Embase (September 2011 to July 2017) and the CENTRAL (2017, Issue 7) to identify all randomized controlled trial (RCT) in MM up to July 2017 using a combination of text and MeSH terms.

SELECTION CRITERIA

Any randomized controlled trial (RCT) comparing bisphosphonates versus placebo/no treatment/bisphosphonates and observational studies or case reports examining bisphosphonate-related ONJ in patients with MM were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors extracted the data. Data were pooled and reported as hazard ratio (HR) or risk ratio (RR) using a random-effects model. We used meta-regression to explore statistical heterogeneity. Network meta-analysis using Bayesian approach was conducted.

MAIN RESULTS

In this update, we included four new studies (601 participants), resulting in a total of 24 included studies.Twenty RCTs compared bisphosphonates with either placebo or no treatment and four RCTs involved another bisphosphonate as a comparator. The 24 included RCTs enrolled 7293 participants. Pooled results showed that there was moderate-quality evidence of a reduction in mortality with on OS from 41% to 31%, but the confidence interval is consistent with a larger reduction and small increase in mortality compared with placebo or no treatment (HR 0.90, 95% CI 0.76 to 1.07; 14 studies; 2706 participants). There was substantial heterogeneity among the included RCTs (I² = 65%) for OS. To explain this heterogeneity we performed a meta-regression assessing the relationship between bisphosphonate potency and improvement in OS, which found an OS benefit with zoledronate but limited evidence of an effect on PFS. This provided a further rationale for performing a network meta-analyses of the various types of bisphosphonates that were not compared head-to-head in RCTs. Results from network meta-analyses showed evidence of a benefit for OS with zoledronate compared with etidronate (HR 0.56, 95% CI 0.29 to 0.87) and placebo (HR 0.67, 95% CI 0.46 to 0.91). However, there was no evidence for a difference between zoledronate and other bisphosphonates.The effect of bisphosphonates on disease progression (PFS) is uncertain. Based on the HR of 0.75 (95% CI 0.57 to 1.00; seven studies; 908 participants), 47% participants would experience disease progression without treatment compared with between 30% and 47% with bisphosphonates (low-quality evidence). There is probably a similar risk of non-vertebral fractures between treatment groups (RR 1.03, 95% CI 0.68 to 1.56; six studies; 1389 participants; moderate-quality evidence). Pooled analysis demonstrated evidence for a difference favoring bisphosphonates compared with placebo or no treatment on prevention of pathological vertebral fractures (RR 0.74, 95% CI 0.62 to 0.89; seven studies; 1116 participants; moderate-quality evidence) and skeletal-related events (SREs) (RR 0.74, 95% CI 0.63 to 0.88; 10 studies; 2141 participants; moderate-quality evidence). The evidence for less pain with bisphosphonates was of very low quality (RR 0.75, 95% CI 0.60 to 0.95; eight studies; 1281 participants).Bisphosphonates may increase ONJ compared with placebo but the confidence interval is very wide (RR 4.61, 95% CI 0.99 to 21.35; P = 0.05; six studies; 1284 participants; low-quality evidence). The results from the network meta-analysis did not show any evidence for a difference in the incidence of ONJ (eight RCTs, 3746 participants) between bisphosphonates. Data from nine observational studies (1400 participants) reported an incidence of 5% to 51% with combination of pamidronate and zoledronate, 3% to 11% with zoledronate alone, and 0% to 18% with pamidronate alone.The pooled results showed no evidence for a difference in increase in frequency of gastrointestinal symptoms with the use of bisphosphonates compared with placebo or no treatment (RR 1.23, 95% CI 0.95 to 1.59; seven studies; 1829 participants; low-quality evidence).The pooled results showed no evidence for a difference in increase in frequency of hypocalcemia with the use of bisphosphonates compared with placebo or no treatment (RR 2.19, 95% CI 0.49 to 9.74; three studies; 1090 participants; low-quality evidence). The results from network meta-analysis did not show any evidence for differences in the incidence of hypocalcemia, renal dysfunction and gastrointestinal toxicity between the bisphosphonates used.

AUTHORS' CONCLUSIONS

Use of bisphosphonates in participants with MM reduces pathological vertebral fractures, SREs and pain. Bisphosphonates were associated with an increased risk of developing ONJ. For every 1000 participants treated with bisphosphonates, about one patient will suffer from the ONJ. We found no evidence of superiority of any specific aminobisphosphonate (zoledronate, pamidronate or ibandronate) or non-aminobisphosphonate (etidronate or clodronate) for any outcome. However, zoledronate was found to be better than placebo and first-generation bisposphonate (etidronate) in pooled direct and indirect analyses for improving OS and other outcomes such as vertebral fractures. Direct head-to-head trials of the second-generation bisphosphonates are needed to settle the issue if zoledronate is truly the most efficacious bisphosphonate currently used in practice.

Mesenchymal stem cells expressing osteoprotegerin variants inhibit osteolysis in a murine model of multiple myeloma

The current treatment options for multiple myeloma (MM) osteolytic lesions are mainly combinations of chemotherapy and other small-molecule inhibitors, but toxic side effects still remain a major concern. Studies have shown that osteoclast activity is enhanced in MM patients through increased expression of receptor activator of nuclear factor κB ligand (RANKL), triggering RANK signaling on osteoclast precursors, which results in aggressive bone resorption. Furthermore, osteoprotegerin (OPG), a decoy receptor for RANKL, and the osteogenic potential of mesenchymal stem cells (MSCs) are significantly decreased in myeloma patients with multiple bone lesions. Thus, the use of OPG as a therapeutic molecule would greatly decrease osteolytic damage and reduce morbidity. However, in addition to inhibiting osteoclast activation, OPG binds to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), thereby rendering the tumor cells resistant to TRAIL-induced apoptosis and limiting the use of OPG for therapy. The present study developed a bone-disseminated myeloma disease model in mouse and successfully tested a cell therapy approach using MSCs, genetically engineered to express OPG variants that retain the capacity to bind RANKL, but do not bind TRAIL. Our results of skeletal remodeling following this regenerative stem cell therapy with OPG variants indicated a significant protection against myeloma-induced osteolytic bone damage in areas of major myeloma skeletal dissemination, suggesting the potential of this therapy for treating osteolytic damage in myeloma patients.

The assessment of surgical and non-surgical treatment of stage II medication-related osteonecrosis of the jaw

Background

Non-surgical treatment has generally been recommended for stage II medication-related osteonecrosis of the jaw (MRONJ) in preference to surgery. However, non-surgical treatment is not empirically effective. The aim of this study was to evaluate whether surgical or non-surgical treatment leads to better outcomes for stage II MRONJ.

Material and Methods

In this retrospective study, surgery was performed in a total of 28 patients while 24 patients underwent non-surgical treatment. The outcomes of both treatment approaches after 6 months were evaluated and statistically compared. In addition, risk factors for surgical and non-surgical treatments were assessed for each.

Results

Surgical treatment in 25 patients (89.3%) resulted in success, with failure in 3 patients (10.7%). Non-surgical treatment was successful for 8 patients (33.3%) and failed in 16 patients (66.7%). There was therefore a significant difference between surgical and non-surgical treatment outcomes (P<0.01). Regarding risk factors, in non-surgical treatment primary diseases, medications, and drug holiday had a significant effect on outcomes (P<0.01). Risk factors for surgical treatment could not be clarified.

Conclusions

Surgical treatment is more effective than non-surgical treatment for stage II MRONJ, and drug holiday, primary disease, and medication constitute risk factors in non-surgical treatment.

Key words:Bisphosphonate, bisphosphonate-related osteonecrosis of the jaw, denosumab, management, medication-related osteonecrosis of the jaw.

Evaluation of the Treatment Strategies for Medication-Related Osteonecrosis of the Jaws (MRONJ) and the Factors Affecting Treatment Outcome: A Multicenter Retrospective Study with Propensity Score Matching Analysis

Medication-related osteonecrosis of the jaw (MRONJ) is an adverse event that may inhibit the treatment of primary disease and remarkably influence the patient's quality of life. The treatment methods for MRONJ, nonsurgical and surgical, are controversial, with no agreement as to which method provides the best outcome and should therefore be recommended. This multicenter retrospective study aimed to investigate the treatment methods and outcome in a large number of patients with MRONJ in Japan, utilizing propensity score matching analysis. A total of 361 patients with MRONJ, at eight hospitals, were registered in this study retrospectively. Various demographic and treatment-related variables were examined and analyzed to determine their correlation with the treatment outcome. After propensity score matching for treatment methods (nonsurgical versus surgical treatment), 176 patients were analyzed by logistic regression. It was shown that those with low-dose administration of an antiresorptive agent and surgical treatment had better outcomes. Furthermore, in 159 patients who underwent surgical treatment, those who underwent extensive surgery experienced significantly better treatment outcomes than those who underwent conservative surgery. This is the first study to compare treatment methods for MRONJ using propensity score matching analysis. The results indicated that extensive surgical treatment should be performed as first-choice therapy for patients with MRONJ. © 2017 American Society for Bone and Mineral Research.

Exposed necrotic bone in 183 patients with bisphosphonate-related osteonecrosis of the jaw: Associated clinical characteristics

BACKGROUND

The main objective of our study was to identify oral symptoms and signs most likely to be associated with the exposure of necrotic bone in bisphosphonate-related osteonecrosis of the jaw (BRONJ).

MATERIAL AND METHODS

The study group consisted of 183 patients with BRONJ. We recorded data on the underlying disease, bisphosphonate used, location of osteonecrosis, symptoms, pain, fistula development, suppuration, infection, exposed necrotic bone, and BRONJ stage.

RESULTS

The mean age of the patients was 68.22 ± 12.19 years. The sample included 118 (64.5%) women. Breast cancer and multiple myeloma were the most common underlying diseases, and 50 patients received oral bisphosphonates for osteoporosis. Dental extractions (69.4%) and mandibular location (74.3%) predominated. The only two variables influencing the possibility of necrotic bone exposure were intravenous bisphosphonate administration and the presence of an intraoral fistula (p < 0.05).

CONCLUSIONS

Intravenous bisphosphonate use and intraoral fistula presence were associated with a major predisposition to bone exposure in patients with BRONJ.

Medication-Related Osteonecrosis of the Jaw: a Brief Review, Treatment and Practical Guidelines for Dentists

Osteonecrosis of the jaws is a complication after treatment with antiresorptive drugs. Bisphosphonates (BPs) are widely used to treat conditions with bone metastases of malignant tumors such as multiple myeloma, breast cancer, prostatic cancer, as well as hypercalcemia of malignancy, osteoporosis, Paget’s disease, and osteogenesis imperfecta. Denosumab is an antiresorptive agent that is used for the treatment of osteoporosis or metastatic bone diseases. These antiresorptive agents improve the quality of life of patients by increasing strength and bone mineral density, and reducing the risk of bone fractures. More than a decade had passed since the first publication of this pathology, and the occurrence of the disease, its pathophysiology, and proper treatment methods are still not fully elucidated. Prevention is critical in medication-related osteonecrosis of the jaw, because the treatment is difficult, and there are no universally accepted treatment protocols. There is an accepted approach of palliation of symptoms and controlling the associated infections. Treatment may follow one of three procedures: conservative management of pain, conservative or extensive (segmental) surgery, depending on the disease stage.

Medication-Related Osteonecrosis of the Jaw and Dental Implants Failures: A Systematic Review

No well-established evidence supporting safe use of bisphosphonates (BPs) or other antiresorptive agents prior, during, or after dentoalveolar surgery, are currently available; moreover, the real risk of osteonecrosis of the jaw (ONJ) development is still unknown. The aim of the present systematic review was to assess the scientific literature concerning the implants placement in antiresorptive agent users and the related risk of implants failure and ONJ development. English papers published from January 2003 until December 2014 were identified on the MEDLINE database. Titles and abstracts retrieved form electronic search were screened separately by 2 examiners; thus, original studies dealing with dental implants placement during or before bone antiresorptive agent therapy and the relative risk of implant failure or development of osteonecrosis were evaluated. Due to the heterogeneity of the included studies and the high risk of bias, there is no evidence of the safe use of oral antiresorptive agents prior or after dental implant surgery. Indeed, implant failure and ONJ development can occur and represent a devastating side effect that should be considered during treatment. Within the limitation of the present systematic review, high quality studies are needed to provide an adequate level of evidence regarding the safety of dentoalveolar surgery during or before bone resorption inhibition therapy and the increase predisposition to osteonecrosis of the jaw (ONJ) development. Therefore, antiresorptive agent therapy should be considered a risk factor until further evidence is prospectively obtained.

Laser and Platelet-Rich Plasma to treat Medication-Related Osteonecrosis of the Jaws (MRONJ): a case report

Aims

The appropriate management of Medication-Related OsteoNecrosis of the Jaw (MRONJ) is still a challenge for dentists and oral surgeons and in these last years high-technology instruments have been proposed at the different steps of interventions, also combined with promoters of tissue repair.The aim of this report is to show the advantages of a combined approach (laser and PRP) for the treatment of MRONJ.

Methods

It is described the case of a patient positive for MRONJ observed at the Odontostomatology and Maxillo-Facial Surgery Unit of the Hospital of Piacenza where surgical approach was performed by using different devices: Er:YAG laser (2940 nm) to remove and vaporize necrotic hard tissue until bleeding bone; Platelet-Rich Plasma (PRP) to stimulate hard and soft tissue healing; diode laser (808 nm) to biostimulate the surgical site.

Results

At the time of suture removal, wound closure was observed and the complete healing of the MRONJ site was observed for the 2 years follow up.

Conclusion

This case may suggest that this kind of combined approach during all the steps of MRONJ treatment allows to perform a faster and less invasive surgery with a more comfortable postoperative healing process and it represents an innovative approach in this severe adverse event.

Analysis of different therapeutic protocols for osteonecrosis of the jaw associated with oral and intravenous bisphosphonates

Introduction

Chemotherapy-associated osteonecrosis of the jaw caused by bisphosphonates is an exposure of necrotic bone with more than eight weeks of evolution that is attributable to bisphosphonates and no prior radiation therapy. Its etiopathogenesis remains unknown, although there are two hypotheses that may explain it: the drug’s mechanism of action, and the risk factors that can lead to osteonecrosis. There is a wide range of treatment options for managing chemotherapy-associated osteonecrosis of the jaw, from conservative treatments to surgical procedures of varying levels of invasiveness, which are sometimes supplemented with adjuvant therapies.

Objectives

The objective of this article is to group the therapeutic options for osteonecrosis of the jaw (ONJ) into seven different protocols and to evaluate their effectiveness in relation to stage of ONJ.

Material and Methods

A literature review was carried out in PubMed following the PRISMA criteria. A total of 47 were collected after compiling a series of variables that define ONJ, applied treatments, and the clinical results obtained.

Results and Discussion

The 47 articles selected have a low to average estimated risk of bias and are of moderate to good quality. According to the data obtained, Protocol 3 (conservative treatment, clinical and radiological follow-up, minimally invasive surgical treatment, and adjuvant therapies) is the most favorable approach for ONJ lesions caused by oral bisphosphonates. For lesions caused by intravenous bisphosphonates, Protocol 2 (conservative treatment, clinical and radiological follow-up, minimally invasive surgical treatment, and no adjuvant therapies) is the best approach. When comparing the different stages of ONJ, Protocol 1 (conservative treatment, clinical and radiological follow-up) promotes better healing of Stage 1 ONJ lesions caused by orally administered bisphosphonates, and Protocol 3 is recommended for Stage II. For ONJ lesions attributable to intravenous bisphosphonates, Protocol 7 (conservative treatment, clinical and radiological follow-up, and adjuvant therapies) provides the best results in Stage 0; in Stages I, II, and III, Protocol 1 gives better results.

Key words:Bisphosphonates, bronj, therapeutic protocol, clinical result.

Prophylaxis and antibiotic therapy in management protocols of patients treated with oral and intravenous bisphosphonates

INTRODUCTION

Osteonecrosis of the jaw (MRONJ) linked to bisphosphonate treatment has specific characteristics that render its therapeutic management challenging for clinicians. Poor response to standard treatment makes it essential to take special precautions when treating this type of disease; therefore, antibiotic prophylaxis and/or antibiotic therapy have been proposed as effective and helpful tools in these situations.

OBJECTIVES

This article seeks to assess published evidence in order to evaluate the different protocols used for antibiotic prophylaxis and/or antibiotic therapy in the general context of patients treated with bisphosphonates.

MATERIAL AND METHODS

A literature review of the last 10 years was carried out in PubMed using the following keywords: "antibiotic prophylaxis and osteonecrosis," "bisphosphonates AND osteonecrosis AND dental management," "bisphosphonate AND osteonecrosis AND antibiotic prophylaxis AND oral surgery." A total of 188 articles were obtained, of which 18 were ultimately selected.

RESULTS AND DISCUSSION

In patients treated with oral and intravenous bisphosphonates without chemotherapy-associated osteonecrosis of the jaw, antibiotic prophylaxis prior to oral surgery is an important tool to avoid osteonecrosis and promote healing of the affected area. If the patient previously exhibited chemotherapy-associated osteonecrosis after tooth extraction, antibiotic prophylaxis is indicated to prevent recurrent osteonecrosis and promote healing of the extraction site. If chemotherapy-associated osteonecrosis is already present, antibiotic therapy is a vital part of conservative management to reduce the symptomatology of MRONJ and keep it from worsening. Finally, a lack of clinical data and randomized controlled trials makes it difficult to choose the most appropriate protocol for the various clinical situations studied. Key words:Bisphosphonates, antibiotic prophylaxis, maxillary osteonecrosis, antibiotic treatment.

Bisphosphonates in the treatment of osteoporosis: a review of skeletal safety concerns

The use of bisphosphonates in treatment of osteoporosis declined significantly over the past decade. There is currently great concern, among patients and physicians, about two potential skeletal adverse effects associated with bisphosphonates- jaw osteonecrosis and atypical femur fractures. This has become a major public health issue since untreated osteoporosis carries a significant burden in terms of fracture-related morbidity and mortality, and bisphosphonates, considered first-line therapy for osteoporosis, have established efficacy in fracture and mortality reduction. Areas covered: In this review we discuss current literature on osteonecrosis of the jaw and atypical femur fractures in patients with osteoporosis treated with bisphosphonates, including case definition, pathogenesis, epidemiology, risk factors, clinical presentation, management and prevention. We conducted a literature search using PubMed and PubMed Central, using the search terms 'bisphosphonates', 'osteonecrosis of the jaw', and 'atypical fractures'. We selected relevant articles including meta-analyses, clinical trials, observational studies, and major society guidelines published between 2010 and 2016, to be included in this review. A few articles published prior to 2010 were also included as references. Expert commentary: The rare skeletal side effects of bisphosphonates should not preclude their use in patients with osteoporosis and high fracture risk, as benefits significantly outweigh the risks.

Case-Based Review of Osteonecrosis of the Jaw (ONJ) and Application of the International Recommendations for Management From the International Task Force on ONJ

Osteonecrosis of the jaw (ONJ) has been associated with antiresorptive therapy in both oncology and osteoporosis patients. This debilitating condition is very rare and advances in diagnosis and management may now effectively reduce the risk of its development and offer valuable treatment options for affected patients. This paper provides a case-based review of ONJ and application of the International Task Force on ONJ (referred to as the "Task Force") recommendations for the diagnosis and management of ONJ. The Task Force was supported by 14 international societies and achieved consensus from representatives of these multidisciplinary societies on key issues pertaining to the diagnosis and management of ONJ. The frequency of ONJ in oncology patients receiving oncology doses of bisphosphonate (BP) or denosumab is estimated at 1%-15%, and the frequency in the osteoporosis patient population receiving much lower doses of BP or denosumab is estimated at 0.001%-0.01%. Although the diagnosis of ONJ is primarily clinical, imaging may be helpful in confirming the diagnosis and staging. In those with multiple risk factors for ONJ for whom major invasive oral surgery is being planned, interruption of BP or denosumab therapy (in cancer patients) is advised, if possible, before surgery, until the surgical site heals. Major oral surgery in this context could include multiple extractions if surgical extractions are required, not simple forceps extractions. ONJ development may be reduced by optimizing oral hygiene and postoperatively using topical and systemic antibiotics as appropriate. Periodontal disease should be managed before starting oncology doses of BP or denosumab. Local debridement may be successful in disease unresponsive to conservative therapy. Successful surgical intervention has been reported in those with stage 3 disease; less severe disease is best managed conservatively. Teriparatide may be helpful in healing ONJ lesions and may be considered in osteoporosis patients at a high fracture risk in the absence of contraindications. Resumption of BP or denosumab therapy following healing of ONJ lesions is recommended, and there have not been reports of subsequent local recurrence.

Medication-Related Osteonecrosis of the Jaw: An Autofluorescence-Guided Surgical Approach Performed with Er:YAG Laser

OBJECTIVE

The aim of this study was to propose an autofluorescence (AF)-guided surgical approach performed with Er:YAG laser and Nd:YAG low-level laser therapy (LLLT).

BACKGROUND DATA

Medication-related osteonecrosis of the jaw (MRONJ) therapy remains an unresolved problem. The proposed conservative and surgical treatment regimens are associated with contradictory success rates. However, the increased experience with MRONJ management suggests that surgical therapy can halt disease progression, and can allow a histology-based diagnosis of osteonecrosis. Surgical approach with Er:YAG laser is associated with significantly better results compared with medical treatment and traditional surgical approaches. One of the difficulties encountered during surgical removal of a MRONJ is the precise individuation of necrotic bone margins.

PATIENT AND METHODS

A case of Stage III maxillary osteonecrosis treated with a new surgical approach is presented.

RESULTS

After 7 months of follow-up, complete mucosal healing was evident, and the patient was free of symptoms. Such a technique allowed a highly accurate and minimally invasive approach through the selective ablation of the non-/hypofluorescent areas.

CONCLUSIONS

Taking into account the advantages of laser therapy and the possible effectiveness of AF in highlighting surgical margins, this approach would probably achieve excellent outcomes.

Treatment of osteonecrosis of the jaw related to bisphosphonates and other antiresorptive agents

Background

The clinical management of medication-related osteonecrosis of the jaw (MRONJ) in patients treated with bisphosphonates and other antiresorptive agents is subject to controversy. The American Association of Oral and Maxillofacial Surgeons (AAOMS) has developed guidelines for the correct management of the disorder which are revised and updated by a panel of experts.

Material and Methods

The present systematic review analyzes the different treatments currently used to treat this clinical condition, based on the PRISMA® (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement published in 2009. An electronic Medline search was made of the PubMed database, covering the period 2006-2014. The last search date was 31 December 2014.

Results

A total of 29 articles were selected from the initial search according to the different drugs implicated in the appearance of osteonecrosis; the treatment modality used according to the stage of the disease; and the recorded success rate.

Conclusions

It is currently still recommended that the management of MRONJ should be decided according to the stage of the disease – conservative treatment being preferred in early stages without symptoms, while surgical management is preferred in the case of bone exposure with symptoms.

Key words:Osteonecrosis, medication, bisphosphonates, treatments, review

Essential roles of the interaction between cancer cell-derived chemokine, CCL4, and intra-bone CCR5-expressing fibroblasts in breast cancer bone metastasis

From a murine breast cancer cell line, 4T1, we established a subclone, 4T1.3, which consistently metastasizes to bone upon its injection into the mammary fat pad. 4T1.3 clone exhibited similar proliferation rate and migration capacity as the parental clone. However, the intra-bone injection of 4T1.3 clone caused larger tumors than that of the parental cells, accompanied with increases in fibroblast, but not osteoclast or osteoblast numbers. 4T1.3 clone displayed an enhanced expression of a chemokine, CCL4, but not its specific receptor, CCR5. CCL4 shRNA-transfection of 4T1.3 clone had few effects on its in vitro properties, but reduced the tumorigenicity arising from the intra-bone injection. Moreover, intra-bone injection of 4T1.3 clone caused smaller tumors in mice deficient in CCR5 or those receiving CCR5 antagonist than in wild-type mice. The reduced tumor formation was associated with attenuated accumulation of CCR5-positive fibroblasts expressing connective tissue growth factor (CTGF)/CCN2. Tumor cell-derived CCL4 could induce fibroblasts to express CTGF/CCN2, which could support 4T1.3 clone proliferation under hypoxic culture conditions. Thus, the CCL4-CCR5 axis can contribute to breast cancer metastasis to bone by mediating the interaction between cancer cells and fibroblasts in bone cavity.

Resection and microvascular reconstruction of bisphosphonate-related osteonecrosis of the jaw: The role of microvascular reconstruction

BACKGROUND

Current treatment guidelines caution against osseous reconstruction using free flap tissue to treat bisphosphonate-related osteonecrosis of the jaw (BRONJ). The primary rationale for this stance is the theoretical risk of nonunion and recurrence of disease within the reconstruction. Emerging evidence suggests that these theoretical risks may be overestimated. We performed a literature review of this procedure for the treatment of advanced BRONJ. We also present a new case report of resection and microvascular reconstruction in a 58-year-old man with stage III BRONJ.

METHODS

A MEDLINE search was performed to gather all reports of maxillary and mandibular reconstruction using free tissue flap transfer for BRONJ. Inclusion criteria were confirmed stage II or III BRONJ, free tissue transfer and reconstruction, and reported complications. Articles were excluded if they contained only local flap reconstruction, wound closure without reconstruction, or osteoradionecrosis. Outcomes from our case report were added to the analysis.

RESULTS

We identified 10 articles that met criteria. Adding our case, we identified 40 cases of free flap reconstruction. The rate of nonunion was 5% (2 of 40). Fistulas formed in 4 cases (10%). BRONJ recurred in 2 cases (5%).

CONCLUSION

Complication rates after free flap microvascular reconstruction in BRONJ seem acceptable. Nonunion is relatively rare and should not be the sole reason to recommend against free flap reconstruction. A randomized clinical trial would help clarify the role of this procedure in refractory BRONJ; however, we believe that segmental resection and microvascular reconstruction is a viable option in select cases of BRONJ. © 2016 Wiley Periodicals, Inc. Head Neck 38:1278-1285, 2016.

Bone microenvironment-mediated resistance of cancer cells to bisphosphonates and impact on bone osteocytes/stem cells

Anti-resorptive bisphosphonates (BPs) have been clinically used to prevent cancer-bone metastasis and cancer-induced bone pathologies despite the fact that the phenotypic response of the cancer-bone interactions to BP exposure is "uncharted territory". This study offers unique insights into the interplay between cancer stem cells and osteocytes/osteoblasts and mesenchymal stem cells using a three-dimensional (3D) live cancer-bone interactive model. We provide extraordinary cryptic details of the biological events that occur as a result of alendronate (ALN) treatment using 3D live cancer-bone model systems under specific bone remodeling stages. While cancer cells are susceptible to BP treatment in the absence of bone, they are totally unaffected in the presence of bone. Cancer cells colonize live bone irrespective of whether the bone is committed to bone resorption or formation and hence, cancer-bone metastasis/interactions are though to be "independent of bone remodeling stages". In our 3D live bone model systems, ALN inhibited bone resorption at the osteoclast differentiation level through effects of mineral-bound ALN on osteocytes and osteoblasts. The mineral-bound ALN rendered bone incapable of osteoblast differentiation, while cancer cells colonize the bone with striking morphological adaptations which led to a conclusion that a direct anti-cancer effect of BPs in a "live or in vivo" bone microenvironment is implausible. The above studies were complemented with mass spectrometric analysis of the media from cancer-bone organ cultures in the absence and presence of ALN. The mineral-bound ALN impacts the bone organs by limiting transformation of mesenchymal stem cells to osteoblasts and leads to diminished endosteal cell population and degenerated osteocytes within the mineralized bone matrix.

Osteonecrosis of the jaw (ONJ): diagnosis and management in 2015

Osteonecrosis of the jaw (ONJ) has been associated with the use of aminobisphosphonates and denosumab. The vast majority (>90%) of cases occur in the oncology patient population receiving high doses of intravenous bisphosphonates or subcutaneous denosumab. The incidence of ONJ in the osteoporosis patient population is very low and is estimated at 1-90 per 100,000 patient-years of exposure. In the oncology patient population the incidence appears to be related to dose and duration of exposure, and prevalence has been estimated to be as high as 18.6%. A number of risk factors in addition to antiresorptive therapy have been identified. These include the presence of periodontal disease, oral surgical procedures with extractions or implants, radiation therapy, chemotherapy, diabetes, glucocorticoid use, and smoking. Antiangiogenic agents appear to contribute to the risk of ONJ, however, data at this time are limited and further evidence is required prior to confirming a causal relationship. ONJ may be prevented with optimization of oral hygiene, the use of oral antimicrobial mouth rinses, as well as systemic antibiotic therapy. Individuals not responding to conservative management or in the advanced stages of ONJ may be considered for surgery, as data over the past several years have demonstrated surgical success in this patient population. Case reports have indicated that teriparatide may enhance healing. A number of experimental therapies are being evaluated and include the use of bone marrow stem cell intralesional transplantation, local application of platelet-derived growth factor, hyperbaric oxygen, tissue grafting, and low-level laser therapy. This paper summarizes the current research as well as the international consensus on the diagnosis and management of ONJ.