Temporal correlation between bisphosphonate termination and symptom resolution in osteonecrosis of the jaw: a pooled case report analysis

Preventing bisphosphonate induced osteonecrosis of the jaw with a polyguanidine conjugate (GuaDex): A promising new approach

Osteonecrosis of the jaw (ONJ) is a relatively rare side effect after prolonged use of bisphosphonates, which are drugs used to treat bone resorption in osteoporosis and certain cancers. This study introduces a novel ONJ model in rats by combining exposure to bisphosphonates, oral surgery, and bacterial inoculation. Potential ONJ preventive effects of polyguanidine (GuaDex) or antibiotics were evaluated. The study consisted of twenty-four male Wistar rats were divided into four groups. Groups 1 to 3 were given weekly doses of i.v. Zoledronic acid (ZA), four weeks before and two weeks after an osteotomy procedure on their left mandibular first molar. Group 4 was a negative control. Streptococcus gordonii bacteria were introduced into the osteotomy pulp chamber and via the food for seven days. On day eight, the rats were given different treatments. Group 1 was given a GuaDex injection into the osteotomy socket, Group 2 was given an intramuscular (i.m.) injection of clindamycin, Group 3 (positive control) was given an i.m. injection of saline, and Group 4 was given an i.m. injection of saline. Blood samples were taken two weeks after the osteotomy procedure, after which the rats were euthanized. Bone healing, bone mineral density, histology, and blood status were analyzed. The results showed that Group 1 (GuaDex) had no ONJ, extensive ongoing bone regeneration, active healing activity, vascularization, and no presence of bacteria. Group 2 (clindamycin) showed early stages of ONJ, avascular areas, and bacteria. Group 3 showed stages of ONJ, inflammatory infiltrates, defective healing, and bacterial presence, and Group 4 had normal healing activity and no bacterial presence. Conclusion: ZA treatment and bacterial inoculation after tooth extraction inhibited bone remodeling/healing and induced ONJ characteristic lesions in the rats. Only GuaDex apparently prevented ONJ development, stimulated bone remodeling, and provided an antimicrobial effect.

The Effectiveness of Hyperbaric Oxygen Therapy on Older Patients With Medication-Related Osteonecrosis of the Jaws: A Case Series

Medication-related osteonecrosis of the jaws (MRONJ) has emerged as one of the major adverse effects of antiresorptive agents in the treatment of patients with cancer and osteoporosis. MRONJ presents as a chronic inflammation of the maxillary and/or mandibular bones accompanied by necrotic bone exposure and intra-/extraoral fistula. Given the increasing number of patients with MRONJ, surgical treatment is highlighted to be significantly beneficial for those patients. However, extensive surgical treatment generally induces physiological and psychological burden on patients with MRONJ. Specifically, older patients with advanced MRONJ require further concerns about their systemic conditions. Thus, oral surgeons are obliged to consider their conditions when determining the indications for extensive surgical treatment. Recently, our department has established a novel therapeutic strategy based on hyperbaric oxygen (HBO) therapy for patients with advanced MRONJ. In this study, we report cases of three older patients with MRONJ who received the combination of conventional treatment and HBO therapy, which resulted in successful management and the avoidance of extensive surgical treatment.

Relationship between Medication-Related Osteonecrosis of the Jaw and CDK4/6 Inhibitors in Breast Cancer

OBJECTIVE

We aimed to evaluate the use of CDK4/6 inhibitors as a risk factor for medication-related osteonecrosis of the jaw (MRONJ) in a cohort of patients with metastatic breast cancer treated with denosumab.

METHODS

This was a multicentre, retrospective, observational study. All patients with breast cancer treated with denosumab (January 2011-December 2022) were included. The relationship between CDK4/6 inhibitors and MRONJ was analysed.

RESULTS

A total of 243 patients were included, ninety-five (44.2%) of whom used a CDK4/6 inhibitor. There were 21 patients with MRONJ. In patients treated with denosumab without CDK4/6 inhibitors, the incidence of MRONJ and mean time to the occurrence of MRONJ were 6.6% (8/120) and 16.8 months (SD 7.8), respectively; in patients treated with denosumab and CDK4/6 inhibitor, these values were 13.7% (13/95) and 15.4 months (SD 8.7), respectively. The difference in the incidence was not significant (p = 0.085). Among the 19 patients who used abemaciclib, the probability of MRONJ occurrence was significantly higher compared to patients not using CDK4/6 inhibitors (p = 0.0178).

CONCLUSIONS

These results suggest that the incidence of MRONJ in patients with metastatic breast cancer treated with denosumab is higher, and the onset of MRONJ occurs earlier in the presence of CDK4/6 inhibitors. The differences were statistically significant in the patients who used abemaciclib. Given that the use of this combination is very common in routine clinical practice, it would be advisable to carry out larger prospective studies to clarify the risk of this association.

Case series of medication-related osteonecrosis of the jaw (MRONJ) patients prescribed a drug holiday

The role of a drug holiday in the management of medication-related osteonecrosis of the jaw (MRONJ) remains controversial. Current UK guidance does not recommend this practice given the lack of conclusive evidence, and potential risk of skeletal-related events or cancer metastasis. This paper aims to describe a series of fifty patients with confirmed MRONJ who were prescribed a drug holiday as part of their management. Data were collected on exposures including: anti-resorptive and/or anti-angiogenic drug history, duration of drug, method of administration, concurrent therapy, MRONJ stage, management of MRONJ and duration of drug holiday. The primary outcome was complete healing as documented in the clinical notes. Multivariate Cox regression analysis was performed to evaluate the association between exposures and primary MRONJ outcome. Models were adjusted for age, sex, and index of multiple deprivation. Survival analysis was performed using a log-rank test, censoring any patients with no primary outcome recorded (p < 0.05). A total of 44% of patients stopped their medication for >36 months. Over half of all MRONJ cases presented in the posterior mandible and dental extraction was the most common precipitating factor (76%). Almost three-quarters (72%) of patients achieved complete healing. MRONJ recurrence (new site) was reported at 30%, mainly in those with incomplete healing of the initial area. There was a lack of evidence for an association between all recorded exposures and the primary MRONJ outcome using multivariate Cox regression. Similarly, we did not demonstrate evidence for an association between the duration of the drug holiday and MRONJ outcome. Our results support published guidelines, which do not recommend the discontinuation of bone modifying drugs for the prevention of MRONJ, or as part of treatment for established MRONJ.

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.

Bone Targeting Agents in Patients with Prostate Cancer: General Toxicities and Osteonecrosis of the Jaw

Introduction: Bone metastases are the most frequent site of secondary localization of prostate cancer (PCa) and are present in about 90% of cases of advanced disease. Consequently, an adequate management of bone involvement is of pivotal importance in the therapeutic approach and skeletal-related events (SREs) need to be closely monitored and promptly assessed and treated. Bone targeting agents (BTAs), consisting in bisphosphonates and denosumab, are an essential part of the treatment of metastatic prostate cancer that accompanies systemic treatments throughout the most part of the history of the disease. Activity and safety of bone targeting agents: These treatments are correlated to better outcomes in terms of reduction of SREs and, in metastatic castration resistant setting, of increased overall survival (OS), but several important adverse events have to be managed and prevented. Of these, osteonecrosis of the jaw (ONJ) is extremely invalidating and should be managed with a special attention. Discussion: The role of BTAs in prostate cancer is pivotal throughout many stages of the disease, but several toxicities should be quickly recognized and treated. We aim at recollecting evidence on clinical benefit of BTAs, common and specific toxicities, and explore the pathophysiology and clinical aspects of osteonecrosis of the jaw. We present a review of the literature to report the role of the different types of bone targeting agents in the management of prostate cancer with bone metastases with a particular focus on common toxicities and ONJ to recollect current evidences on the activity of these compounds and the correct management of their adverse events.

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.

Various Therapeutic Methods for the Treatment of Medication-Related Osteonecrosis of the Jaw (MRONJ) and Their Limitations: A Narrative Review on New Molecular and Cellular Therapeutic Approaches

Medication-related osteonecrosis of the jaw (MRONJ) is one of the most interesting diseases in the field of maxillofacial surgery. In addition to bisphosphonates, the use of antiresorptive and antiangiogenic agents is known to be the leading cause. However, the exact pathogenesis of MRONJ has not been established, and various hypotheses have been proposed, such as oxidative stress-related theory. As a result, a definitive treatment protocol for MRONJ has not been identified, while various therapeutic approaches are applied to manage patients with MRONJ. Although the surgical approach to treat osteomyelitis of the jaw has been proven to be most effective, there are limitations, such as recurrence and delayed healing. Many studies and clinical trials are being conducted to develop another effective therapeutic modality. The use of some materials, including platelet concentrates and bone morphogenetic proteins, showed a positive effect on MRONJ. Among them, teriparatide is currently the most promising material, and it has shown encouraging results when applied to patients with MRONJ. Furthermore, cell therapy using mesenchymal stem cells showed promising results, and it can be the new therapeutic approach for the treatment of MRONJ. This review presents various treatment methods for MRONJ and their limitations while investigating newly developed and researched molecular and cellular therapeutic approaches along with a literature review.

Osteonecrosis of the jaw associated with imatinib therapy in myeloproliferative neoplasm: a rare case report

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively infrequent but very well-known adverse effect of bisphosphonates. This rare complication of bisphosphonates is rarest with the use of certain drugs. Tyrosine kinase inhibitors (TKIs), particularly used in renal cell carcinoma or gastrointestinal tumors as a chemotherapeutic agent, can precipitate this particular medical condition of bone when it is associated with either radiation or bisphosphonates, though, monodrug therapy with TKIs rarely causes MRONJ. This article describes a rare case of necrosis of the jawbone in a patient with a myeloproliferative neoplasm who was receiving the TKI imatinib and had no history of bisphosphonate or radiation therapy to head and neck region.

Apical surgery in cancer patients receiving high-dose antiresorptive medication-a retrospective clinical study with a mean follow-up of 13 months

PURPOSE

The aim of the study is to evaluate the results of apical surgery (AS) in patients receiving high-dose antiresorptive medication (HDAR).

METHODS

Retrospective descriptive quality control study conducted in an Oral and Maxillofacial Department at a University Hospital. Fourteen patients on HDAR met the inclusion criteria. Only descriptive statistics were applied.

RESULTS

Fourteen patients had operation on seventeen teeth. Mean HDAR treatment period before apical surgery: 25 months (SD, ± 24.27; range, 1-78 months). Drug holiday during surgery and initial healing: mean, 8 months (SD, ± 5.96; range, 0.4-22 months). Sixteen out of seventeen teeth healed clinically and showed complete or ongoing radiographic healing. All patients except one became free of symptoms. Mean follow-up: 13 months (SD, ± 9.05; range, 2-31 months). Radiographic healing according to Molven and Rud: 7, complete; 6, uncertain; 1, unsatisfactory. Three patients died during follow-up and were considered drop-outs.

CONCLUSIONS

The present case series suggest that apical surgery is a valid treatment option for apical periodontitis in patients on HDAR, where orthograde endodontic retreatment is not possible. None of the patients developed medication-related osteonecrosis of the jaw. Further studies in larger study groups and with longer follow-up periods are needed. The regional scientific ethical committee provided a document exemption, registration date 20 November 2013, and the local data protection agency approved handling of the recorded data (No. 2012-41-0045), registration date 11 January 2012.

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.

Oral Surgical Management of Bone and Soft Tissues in MRONJ Treatment: A Decisional Tree

Background: The aim of the present work was to analyze a 10-year retrospective series of surgically treated medication-related osteonecrosis of the jaws (MRONJ) cases, reporting the clinical outcome and success rate for each adopted procedure in order to draw a treatment algorithm that is able to standardize clinical decision making and maximize the success of oral surgical treatment of MRONJ. Methods: Different surgical approaches were categorized taking into consideration two variables (a) hard tissue management (defined as debridement, saucerization or marginal resective surgery of maxillary necrotic bone) and (b) soft tissue management (defined as type of flap design and related modality of wound-healing). Results: For the retrospective cohort study, 103 MRONJ patients were enrolled and a total of 128 surgical procedures were performed. The role of radical-intended surgery using local flaps in MRONJ treatment was investigated, as well as palliative treatments. All stage I–II patients completely healed when a combination of radical necrotic bone surgery associated with a first intention healing of soft tissues was obtained. In stage III, when a patient was not eligible for maxillo-facial surgery, the use of palliative surgical strategies was effective in symptom relief in order to maintain a better quality of life for the duration of the patient’s life. Conclusions: Oral surgery with radical intent associated with a flap design able to ensure first intention healing might represent a valid option for the majority of MRONJ patients. The designed decision tree allows clinicians to assess individual surgical approaches for MRONJ treatment in accordance with patient-centered outcomes and surgical skills.

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.

Lactoferrin and oral pathologies: a therapeutic treatment

The oral cavity is a non-uniform, extraordinary environment characterized by mucosal, epithelial, abiotic surfaces and secretions as saliva. Aerobic and anaerobic commensal and pathogenic microorganisms colonize the tongue, teeth, jowl, gingiva, and periodontium. Commensals exert an important role in host defenses, while pathogenic microorganisms can nullify this protective function causing oral and systemic diseases. Every day, 750-1000 mL of saliva, containing several host defense constituents including lactoferrin (Lf), are secreted and swallowed. Lf is a multifunctional iron-chelating cationic glycoprotein of innate immunity. Depending on, or regardless of its iron-binding ability, Lf exerts bacteriostatic, bactericidal, antibiofilm, antioxidant, antiadhesive, anti-invasive, and anti-inflammatory activities. Here, we report the protective role of Lf in different oral pathologies, such as xerostomia, halitosis, alveolar or maxillary bone damage, gingivitis, periodontitis, and black stain. Unlike antibiotic therapy, which is ineffective against bacteria that are within a biofilm, adherent, or intracellular, the topical administration of Lf, through its simultaneous activity against microbial replication, biofilms, adhesion, and invasiveness, as well as inflammation, has been proven to be efficient in the treatment of all known oral pathologies without any adverse effects.

Drug holiday clinical relevance verification for antiresorptive agents in medication-related osteonecrosis cases of the jaw

Treatment strategies of medication-related osteonecrosis of the jaw (MRONJ) are controversial. Recently, surgical treatment has been reported as superior to nonsurgical treatment, but the contribution discontinued antiresorptive agent use during MRONJ treatment remains unclear. This study aimed to evaluate the efficacy of drug holidays and treatment strategies in MRONJ cases. Four-hundred and twenty-seven patients with MRONJ treated at nine hospitals from 2009 to 2017 were included in this multicenter retrospective study. Multivariate Cox regression analysis showed that the primary disease (osteoporosis or malignant tumor), diabetes, serum albumin, and treatment method (surgical or nonsurgical) were significantly correlated with the cure rate. The cumulative 1-year cure rates in the surgical and nonsurgical treatment groups were 64.7% and 18.2%, respectively. However, discontinuing antiresorptive agents did not influence the treatment outcome in the cohort overall, or in 230 patients after performing propensity score matching among the discontinuation and continuation groups. When stratifying by treatment method, antiresorptive agent discontinuation significantly increased the cure rate in patients with osteoporosis who underwent nonsurgical treatment. In patients with malignant tumors undergoing nonsurgical therapy, discontinuing the antiresorptive agent was associated with a better treatment outcome, but not with statistical significance. In contrast, drug holidays showed no effect on improving outcomes in patients with both osteoporosis and malignant tumors who underwent surgical therapy. Thus, regardless of the primary disease, discontinuing antiresorptive agents during treatment for MRONJ may not be necessary and may be helpful in some cases. Future prospective trials should examine this question further.

Medication-related osteonecrosis of the jaw: definition and best practice for prevention, diagnosis, and treatment

Skeletal complications caused by osteoporosis or bone metastases are associated with considerable pain, increased mortality, and reduced quality of life. Furthermore, such events place a burden on health care resources. Agents that prevent bone resorption, such as bisphosphonates or denosumab, can reduce the risk of skeletal-related events and are widely used in patients with osteoporosis or bone metastases of cancer. Medication-related osteonecrosis of the jaw (MRONJ) is a rare, but potentially serious, adverse event associated with high cumulative doses of bisphosphonates or denosumab. However, MRONJ can be treated, and the likelihood of the development of this condition can be reduced through prophylactic dental care and the maintenance of good oral hygiene. Dentists, as part of a multiprofessional team, have a critical role in preventing MRONJ. This review describes the incidence and pathophysiology of MRONJ and provides guidance for dental practitioners with regard to the screening, prophylactic treatment, diagnosis, and management of patients with this condition.

Efficacy of bovine lactoferrin in the post-surgical treatment of patients suffering from bisphosphonate-related osteonecrosis of the jaws: an open-label study

Osteonecrosis of the jaws is an emerging pathological condition characterized by un-exposure or exposure of the necrotic bone, independently from the etiology. This term is usually referred to medication-related osteonecrosis of the jaws due to severe adverse reaction to certain medicines, as bisphosphonates, used for the treatment of cancer and osteoporosis. The management of patients with Bisphosphonate-Related Osteonecrosis of the Jaws (BRONJ) remains challenging because surgical and medical interventions may not eradicate this pathology. The goal of treatment of patients at risk of developing BRONJ or of those who have active disease is the preservation of quality of life by controlling pain, managing infection, and preventing the development of new areas of necrosis. The treatment of osteonecrosis consists in the surgical removal of necrotic bone followed by antibiotic therapy and application of sterile greasy gauze until the wound closure. The classical medical treatment has been compared with the innovative one consisting in the application of sterile greasy gauze soaked with bovine lactoferrin (bLf) after surgery. Here, for the first time, bLf efficacy on wound repair in subjects suffering from BRONJ with the progressive destruction of bone in the mandible or maxilla has been demonstrated. The positive results consist in a significant shorter time of wound closure (1 or 2 weeks) compared to that observed with classical surgical treatment (2-3 months). These promising results are an interesting tool for the innovative treatment of this pathology and for increasing the quality of life of these patients.

Antiresorptive treatment-associated ONJ

Osteonecrosis of the jaw (ONJ) is a severe complication of therapy with antiresorptive agents (e.g. bisphosphonates and denosumab), which are used to manage bone metastases from cancer, to reduce the incidence of skeletal-related events. Available data indicate that 0-27, 5% of patients exposed to antiresorptive agents may develop ONJ, depending on the number of infusions and the duration of therapy. Besides antiresorptive therapy, a number of risk factors for osteonecrosis have been identified. Oral surgical procedures, tooth extractions and infection to the jawbones are considered the main risk factors for developing ONJ, when receiving antiresorptive therapy. However, a growing number of patients develop ONJ without apparent risk factors, raising concern for other predisposing factors. Jaw bone necrosis may be irreversible, resulting in a chronic disease with negative impact on the quality of patients' lives. The role of risk reduction strategies like meticulous dental screening and optimal oral hygiene is fundamental for preventing development of ONJ. ONJ is usually treated conservatively to relieve the symptoms and manage jaw bone necrosis. In certain cases, surgical intervention is required. Future research should emphasize individual predisposition to ONJ, more effective preventive measures and more efficient therapeutic procedures.

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.

Relevant factors for treatment outcome and time to healing in medication-related osteonecrosis of the jaws - A retrospective cohort study

BACKGROUND

Risk factors for medication-related osteonecrosis of the jaw (MRONJ) are well known, although few studies evaluate the factors that influence treatment outcomes in MRONJ and whether discontinuing antiresorptive medication influences healing.

PURPOSE

(1) Describe the characteristics of a population of patients with MRONJ. (2) Identify the factors associated with favourable outcomes. (3) Identify a temporal correlation between discontinuation of antiresorptives and healing time.

METHODS

A retrospective longitudinal cohort study was carried out, including 77 patients with MRONJ treated between 2004 and 2016. Primary outcome was defined as healed/improved vs. worse/stable. Time to healing was set as the secondary outcome. Statistical significance was defined as p < 0.05.

RESULTS

Primary disease, route of administration, lesion location, and development of complications influenced the outcome of treatment. Significant differences in outcomes according to primary disease (p < 0.05) were found when staging, gender, and lesion location were held constant. Time to healing was longer for patients who discontinued medication more than 3 months after diagnosis than for those who discontinued at diagnosis or before - respectively, 36, 9, and 7 months (p = 0.01).

CONCLUSIONS

The outcome of MRONJ treatment may be influenced by primary disease and route of administration of antiresorptives. Antiresorptive medication discontinuation contributes to reduce healing time in MRONJ.

Effectiveness of treatments for medication-related osteonecrosis of the jaw: A systematic review and meta-analysis

BACKGROUND

The effectiveness of management strategies used for the treatment of medication-related osteonecrosis of the jaw (MRONJ) remains poorly understood. The authors evaluated systematically the effectiveness of the various treatment modalities used for MRONJ.

TYPES OF STUDIES REVIEWED

The authors conducted a comprehensive search of MEDLINE, Embase, the Cochrane Library, and Scopus to identify randomized controlled trials, nonrandomized controlled trials, and prospective cohort studies to evaluate comparatively the effectiveness of management strategies for the treatment of MRONJ. The authors conducted the identification of eligible studies in duplicate and synthesized the extracted data by means of a meta-analysis, when feasible.

RESULTS

The authors found 13 studies with a medium-to-high risk of bias that met the inclusion criteria of this review. The authors found that, compared with medical treatment of local antimicrobials with or without systemic antimicrobials, the study investigators associated surgical treatment with higher odds of complete resolution of the condition (2 studies; 76 participants; unadjusted odds ratio, 3.55; 95% confidence interval, 1.12 to 11.19). The effectiveness of other therapies, such as bisphosphonate drug holidays, teriparatide, and hyperbaric oxygen, was uncertain.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

On the basis of the results of an unadjusted analysis, the results of the studies that were deemed to be medium to low quality and to have medium-to-low statistical power suggested that there are higher odds of resolving MRONJ with surgical treatment compared with medical treatment. High-quality research is required for conclusive statements to be made regarding treatment strategies for management of MRONJ.

[Evaluation of healing time of osteochemonecrosis of the jaw after surgery: Single-center retrospective study and review of the literature]

INTRODUCTION

Osteochemonecrosis of the jaw (ONJ) is a chronic ischemic bone exposure. It has an increasing incidence. ONJ is mainly related to bisphosphonate and denosumab therapies in oncologic settings. Healing is considered uncertain ad as occurring slowly. International recommendations suggest to treat ONJ symptomatically in a first attempt. A surgical procedure, potentially aggressive, should be carefully weight up in patients in poor condition and whose life expectancy is often limited. However, surgical treatment seems to allow for a high rate of clinical remission. Postoperative remission periods, when mentioned in the studies, are disparate. The aim of our study was to clarify the remission period of ONJ after surgical management.

METHOD

A retrospective study was conducted on all patients operated for an ONJ at stage 2 and 3 in the Department for Oral and Maxillofacial Surgery - University Hospital of Besançon (France) from January 2006 to September 2015. Healing was defined as complete mucosal closure and asymptomatic site. Stage of the disease, the number and the type of surgery and the time between the last operation and the healing was noticed. These data were compared to an exhaustive review of the literature on PubMed with the following key-words: "osteonecrosis" AND "jaw" AND "surgery" AND "management". Only the articles giving the healing period were included.

RESULTS

Regarding the single-center retrospective study, the files of 23 patients could be included. Fifteen percent of the patients benefited from several procedures under general anesthesia. Twenty percent had a stage 3 ONJ and 80 % had a stage 2 ONJ. Twenty-five interventions were performed on 23 sites in 20 patients. Immediate healing after surgery occurred in 35 % of the patients. At 6 months after surgery, 57 % of the treated areas were healed. Twenty percent of the patients had died. The healing rate did not improve further after 6 months postoperatively. Regarding the review of the literature, 7 articles could be included. The mean postoperative healing period was 60.7 % at 6 months, 71.1 % at 12 months and 69.5 % at 18 months.

DISCUSSION

Our study shows that the postoperative healing rate of ONJ lies between 57 and 66.7 % at 6 months and that this rate was optimized in the order of 10 % to 12months and stable at 18months postoperatively. The ONJ of our series were partially or fully linked to other drugs than bisphosphonates in 70 % of the cases: 50 % were related to denosumab, alone or in combination and 35 % were related to an association with antiangiogenics, bevacizumab mainly.

Antiresorptive agent-related osteonecrosis of the jaw: Position Paper 2017 of the Japanese Allied Committee on Osteonecrosis of the Jaw

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is an intractable, though rare, complication in cancer patients with bone metastases and patients with osteoporosis who are treated with antiresorptive agents, including bisphosphonates and denosumab. Despite the more than 10 years that have passed since the first cases of bisphosphonate-related osteonecrosis of the jaw (BRONJ) were reported, our understanding of the epidemiology and pathophysiology of ARONJ remains limited, and data supported by evidence-based medicine are still sparse. However, the diagnosis and staging of ARONJ, identification of risk factors, and development of preventive and therapeutic approaches have advanced significantly over the past decade. The Position Paper 2017 is an updated version of the Position Paper 2010 of the Japanese Allied Committee on Osteonecrosis of the Jaw, which now comprises six Japanese academic societies. The Position Paper 2017 describes a new diagnostic definition for ARONJ, as proposed by the American Association of Oral and Maxillofacial Surgeons (AAOMS), summarizes our current understanding of the pathophysiology of ARONJ based on a literature search, and suggests methods for physicians and dentists/oral surgeons to manage the disease. In addition, the appropriateness of discontinuing antiresorptive medications (drug holiday) before, during, and after invasive dental treatments is discussed extensively. More importantly, the manuscript also proposes, for the first time, the importance of interactive communication and cooperation between physicians and dentists/oral surgeons for the successful treatment of ARONJ. The Position Paper 2017 is intended to serve as a guide for improving the management of ARONJ patients in Japan.

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.

Hyperparathyroidism Associated with Long-Term Proton Pump Inhibitors Independent of Concurrent Bisphosphonate Therapy in Elderly Adults

OBJECTIVES

To measure the effect of proton pump inhibitors (PPIs), with and without concurrent bisphosphonates, on parathyroid hormone (PTH), vitamin D, and calcium.

DESIGN

Retrospective chart review of individuals 60 years and older. Subjects with reduced renal function (creatinine >1.3 mg/dL) and low vitamin D (<30 ng/mL) were excluded.

SETTING

Academic geriatric outpatient center in southern midwest.

PARTICIPANTS

Individuals aged 60 and older with concurrent calcium, PTH, vitamin D, and creatinine laboratory measurements (N = 80) meeting labeled criteria.

MEASUREMENTS

Serum calcium, PTH, vitamin D, and creatinine.

RESULTS

Chronic PPI exposure was associated with statistically significantly higher PTH (65.5 vs 30.3 pg/mL, P < .001; normal range 10-55 pg/mL) and lower calcium (9.1 vs 9.4 mg/dL, P = .02; normal range 8.5-10.5 mg/dL) than no PPI exposure. Chronic PPI exposure with concurrent BP therapy was associated with statistically significantly higher PTH (65.2 vs 43.4 pg/mL, P = .05) and lower calcium (9.2 vs 9.6 mg/dL, P = .04) than BP therapy only.

CONCLUSION

Based on the present study, chronic PPI exposure in elderly adults is associated with mild hyperparathyroidism regardless of concurrent oral BP administration.