Osteonecrosis of jaw beyond antiresorptive (bone-targeted) agents: new horizons in oncology

Could MRONJ Be Related to Osimertinib Monotherapy in Lung Cancer Patients after Denosumab Suspension?

BACKGROUND

Medication-related osteonecrosis of the jaws is the most frequent complication in patients treated or in therapy with antiresorptive/antiangiogenetic drugs. The list of medications possibly related to MRONJ onset is constantly growing; we aimed to report on a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (Osimertinib) as possibly responsible for bilateral maxillary necrosis onset in the herein-described case.

METHODS

In June 2023, an oncologic patient with two different maxillary bone exposures was referred to our attention. His medical history revealed a two-year Denosumab regimen along with Osimertinib, the latter not suspended before teeth extractions. The clinicians performed a sequestrum removal and bone debridement after three cycles of antibiotic therapy.

RESULTS

Histologic examinations confirmed the clinical diagnosis of MRONJ excluding a metastatic occurrence, while complete mucosal healing was achieved after 15 days.

CONCLUSIONS

The patient suspended Denosumab for more than six months before teeth extraction for MRONJ prevention; hence, failure to discontinue Osimertinib led us to consider it a possible etiological factor. From a literature analysis, only one case has already been published reporting a possible Osimertinib-related occurrence of MRONJ in lung cancer patients. Our case is a further report that could be intended as an alert both for oncologists and dentists to share decisions about the oral management of such patients together, also informing them about this possible risk. Also, this report could trigger in the scientific community the necessity to evaluate further guidelines for similar doubtful cases in which the drug interaction, the mono-suspension, and the possible removable prosthesis-related additional trauma should be considered causes or con-causes.

Awareness of Medication-Related Osteonecrosis of the Jaws Amongst Patients on Antiresorptive and Antiangiogenic Medications

Background Medication-related osteonecrosis of the jaws (MRONJ) is a rare but severe condition that has garnered increasing attention in recent years. It primarily affects individuals undergoing treatment with antiresorptive and antiangiogenic medications, such as bisphosphonates and denosumab, commonly prescribed for osteoporosis and cancer-related bone metastases. Therefore, the present study aimed to assess awareness and understanding of MRONJ among patients receiving antiresorptive and antiangiogenic medications. Methods A cross-sectional survey was conducted among 110 patients receiving antiresorptive and antiangiogenic medications in a clinical setting. Participants were given a structured questionnaire to assess their awareness of MRONJ. The questionnaire covered aspects such as MRONJ, bisphosphonate usage, and awareness of the condition's potential complications. Demographic information was also collected. Chi-square and Fisher's tests were performed using SPSS statistical software. Results In terms of gender distribution, 63.6% of the participants were female. Concerning age distribution, the majority (43.6%) fell within the 21 to 40 age group, whereas only 5.5% were aged over 60. Regarding educational attainment, a substantial majority (58.2%) of the participants held a bachelor's degree. The study findings reveal that a considerable proportion (35.5%) of participants possess awareness regarding jaw osteonecrosis, and this association is statistically significant (p=0.002). A substantial number of participants administered the medication orally (30.9%), while others utilized various administration routes, including injection (IV and others) (40%), and this difference was also statistically significant (p=0.001). Most participants took bisphosphonates for osteoporosis (41.8%) or cancer (13.6%), both statistically significant (p<0.01). Gender had no significant impact (p>0.01), but age showed potential associations (p=0.07 for awareness, p=0.003 for medication use). Educational backgrounds had no significant link, except for bisphosphonate usage (p<0.01) and side effects reporting (p<0.01). Conclusion Notably, a small percentage of participants demonstrated awareness of this condition, indicating a need for continued education and awareness campaigns. Further research and interventions may be warranted to address the specific needs of different age groups and educational backgrounds in promoting safe and effective medication management.

Denosumab and Zoledronic Acid Differently Affect Circulating Immune Subsets: A Possible Role in the Onset of MRONJ

This work investigated whether the anti-resorptive drugs (ARDs) zoledronic acid (Zol) and denosumab (Dmab) affect differently the levels of circulating immune cell subsets, possibly predicting the risk of developing medication-related ONJ (MRONJ) during the first 18 months of treatment. Blood samples were collected from 10 bone metastatic breast cancer patients receiving cyclin inhibitors at 0, 6, 12, and 18 months from the beginning of Dmab or Zol treatment. Eight breast cancer patients already diagnosed with MRONJ and treated with cyclin inhibitors and ARDs were in the control group. PBMCs were isolated; the trend of circulating immune subsets during the ARD treatment was monitored, and 12 pro-inflammatory cytokines were analyzed in sera using flow cytometry. In Dmab-treated patients, activated T cells were stable or increased, as were the levels of IL-12, TNF-α, GM-CSF, IL-5, and IL-10, sustaining them. In Zol-treated patients, CD8+T cells decreased, and the level of IFN-γ was undetectable. γδT cells were not altered in Dmab-treated patients, while they dramatically decreased in Zol-treated patients. In the MRONJ control group, Zol-ONJ patients showed a reduction in activated T cells and γδT cells compared to Dmab-ONJ patients. Dmab was less immunosuppressive than Zol, not affecting γδT cells and increasing activated T cells.

Pathophysiology of Medication-Related Osteonecrosis of the Jaw-A Minireview

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious adverse effect of antiresorptive medications administered for control of osseous malignancy, osteoporosis, or other bone metabolic diseases. Despite being reported in the literature two decades ago, MRONJ etiology, pathophysiology, and progression remain largely unknown, and current nonoperative or operative treatment strategies are mostly empirical. Several hypotheses that attempt to explain the mechanisms of MRONJ pathogenesis have been proposed. However, none of these hypotheses alone is able to capture the complex mechanistic underpinnings of the disease. In this minireview, we aim to highlight key findings from clinical and translational studies and propose a unifying model for the pathogenesis and progression of MRONJ. We also identify aspects of the disease process that require further investigation and suggest areas for future research efforts toward calibrating methodologic approaches and validating experimental findings. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Location and Gender Differences in Osteonecrosis of the Jaws in Patients Treated with Antiresorptive and Antineoplastic Drugs Undergoing Dentoalveolar Surgical, Systematic Review with Meta-Analysis and Trial Sequential Analysis

In the treatment and prevention of osteoporosis and more generally of neoplastic and metabolic pathologies affecting bone tissues, antiresorption drugs such as bisphosphonates and monoclonal antibody are used. Bisphosphonates have been linked to cases of osteonecrosis of the jaws since 2003 by Marx, with more and more evidence over the next two decades; together with bisphosphonate drugs, cases relating to the use of monoclonal drugs have been subsequently added. Among the main independent risk factors, we have extraction procedures in oral surgery that can affect both the mandible and the maxilla and the anterior or posterior sectors. The incidence of MRONJ treated with oral bisphosphonates ranges from 0.5% to 3% according to studies; this incidence would appear to be higher in patients treated with antiresorptive agents with neoplastic diseases. Many pathologies including those in which antiresorptive drugs are used show differences in prevalence in relation to sex; similarly, there could be differences in the incidence of cases of osteonecrosis based on gender in patients undergoing dentoalveolar surgery. Therefore, the objective of this systematic review and trial sequential analysis was to identify and quantify whether there is a proportionally greater risk of MRONJ in male or female subjects and whether there is evidence of greater involvement of osteonecrosis at several extraction sites, differentiating them into mandibular or maxilla and in the anterior or posterior sector. The revision protocol followed the indications of the Cochrane Handbook, and were recorded in Prospero, while the drafting of the manuscript was based on PRISMA. The results of the systematic review, after the study identification and selection process, included a total of 24 studies. The results of the meta-analysis reports: odds ratio (random effects model): 1.476 (0.684, 3.184) between male and female; odds ratio (random effects model): 1.390 (0.801, 2.412) between mandible and maxillary, and an odds ratio value of 0.730 (0.250, 2.137) between the anterior and posterior extraction sites. In conclusion, we can see that there was a trend in the onset of MRONJ as a complication of dentoalveolar surgical procedures, which proportionally mostly involved the male sex and the posterior mandibular sectors, however, this trend must be further confirmed by additional studies.

Molecular events in the jaw vascular unit: A traditional review of the mechanisms involved in inflammatory jaw bone diseases

Inflammatory jaw bone diseases are common in stomatology, including periodontitis, peri-implantitis, medication-related osteonecrosis of the jaw, radiation osteomyelitis of the jaw, age-related osteoporosis, and other specific infections. These diseases may lead to tooth loss and maxillofacial deformities, severely affecting patients' quality of life. Over the years, the reconstruction of jaw bone deficiency caused by inflammatory diseases has emerged as a medical and socioeconomic challenge. Therefore, exploring the pathogenesis of inflammatory diseases associated with jaw bones is crucial for improving prognosis and developing new targeted therapies. Accumulating evidence indicates that the integrated bone formation and dysfunction arise from complex interactions among a network of multiple cell types, including osteoblast-associated cells, immune cells, blood vessels, and lymphatic vessels. However, the role of these different cells in the inflammatory process and the 'rules' with which they interact are still not fully understood. Although many investigations have focused on specific pathological processes and molecular events in inflammatory jaw diseases, few articles offer a perspective of integration. Here, we review the changes and mechanisms of various cell types in inflammatory jaw diseases, with the hope of providing insights to drive future research in this field.

Immune Dysfunction in Medication-Related Osteonecrosis of the Jaw

The pathogenesis of medication-related osteonecrosis of the jaw (MRONJ) is multifactorial and there is a substantial consensus on the role of antiresorptive drugs (ARDs), including bisphosphonates (BPs) and denosumab (Dmab), as one of the main determinants. The time exposure, cumulative dose and administration intensity of these drugs are critical parameters to be considered in the treatment of patients, as cancer patients show the highest incidence of MRONJ. BPs and Dmab have distinct mechanisms of action on bone, but they also exert different effects on immune subsets which interact with bone cells, thus contributing to the onset of MRONJ. Here, we summarized the main effects of ARDs on the different immune cell subsets, which consequently affect bone cells, particularly osteoclasts and osteoblasts. Data from animal models and MRONJ patients showed a deep interference of ARDs in modulating immune cells, even though a large part of the literature concerns the effects of BPs and there is a lack of data on Dmab, demonstrating the need to further studies.

MRONJ in breast cancer patients under bone modifying agents for cancer treatment-induced bone loss (CTIBL): a multi-hospital-based case series

BACKGROUND

Cancer treatment-induced bone loss (CTIBL) is the most common adverse event experienced by patients affected by breast cancer (BC) patients, without bone metastases. Bone modifying agents (BMAs) therapy is prescribed for the prevention of CTIBL, but it exposes patients to the risk of MRONJ.

METHODS

This multicentre hospital-based retrospective study included consecutive non-metastatic BC patients affected by MRONJ related to exposure to low-dose BMAs for CTIBL prevention. Patients' data were retrospectively collected from the clinical charts of seven recruiting Italian centres.

RESULTS

MRONJ lesions were found in fifteen females (mean age 67.5 years), mainly in the mandible (73.3%). The mean duration of BMAs therapy at MRONJ presentation was 34.9 months. The more frequent BMAs was denosumab (53.3%). Ten patients (66.7%) showed the following local risk factors associated to MRONJ development: periodontal disease (PD) in three cases (20%) and the remaining six (40%) have undergone PD-related tooth extractions. One patient presented an implant presence-triggered MRONJ (6.7%). In five patients (33.3%) no local risk factors were observed.

CONCLUSIONS

This is the first case series that investigated BC patients under BMAs for CTIBL prevention suffering from MRONJ. These patients seem to have similar probabilities of developing MRONJ as osteo-metabolic ones. Breast cancer patients under BMAs for CTIBL prevention need a regular prevention program for MRONJ, since they may develop bone metastases and be treated with higher doses of BMAs, potentially leading to a high-risk of MRONJ.

Incidence and risk factors associated to Medication-Related Osteo Necrosis of the Jaw (MRONJ) in patients with osteoporosis after tooth extractions. A 12-months observational cohort study

OBJECTIVE

To evaluate the 12-months incidence of MRONJ after tooth extractions and possible related risk factors in patients with osteoporosis treated by means of oral bisphosphonates.

MATERIAL AND METHODS

Forty-five records of osteoporotic patients on therapy with oral bisphosphonates and treated with at least one dental extraction at the Department of Oral Surgery of University of Naples Federico II were selected. All patients were treated using a standardized surgical extraction protocol. At baseline and after 12-months follow-up, the following variables were recorded: "mucosal healing", "gender", "type of drug"; "duration of therapy"; "drug holiday". The collected data were analyzed and a linear regression analysis was performed to assess a possible correlation with onset MRONJ.

RESULTS

A total of 159 tooth extraction in 43 females (95.6%) and in 2 males (4.4%) with a mean age of 67.5 ± 3 years were available for the analysis. The majority part of patients was on therapy with alendronate (23; 51.2%), 11 patients (24.4%) were treated with risedronate and 11 (24.4%) with ibandronate. Before oral surgery, 84% of the patients showed a low-medium risk of MRONJ, while in 16% of the patients a medium-high risk was recorded. After 12-months follow-up, osteonecrosis was observed in 1 patient, with an overall incidence of MRONJ of 0.6%. The linear regression showed a significant correlation with MRONJ onset only for "gender" variable, with a R² of 0.489.

CONCLUSIONS

Within their limitations, the outcomes of the study indicate that the risk of MRONJ after tooth extraction in osteoporotic patients taking bisphosphonates for OS is very low. A prolonged and specific antibiotic and antiseptic therapy, in addition to a surgical procedure as little traumatic as possible, will allow to perform oral surgery safely.

Medication-related osteonecrosis of the jaw after dental clearance: Prevalence in an oncology center

Objective

Study design

Results

Conclusion

Differentially Expressed Genes Reveal the Biomarkers and Molecular Mechanism of Osteonecrosis

Osteonecrosis is one of the most refractory orthopedic diseases, which seriously threatens the health of old patients. High-throughput sequencing (HTS) and microarray analysis have confirmed as an effective way for investigating the pathological mechanism of disease. In this study, GSE7716, GSE74089, and GSE123568 were obtained from Gene Expression Omnibus (GEO) database and used to identify differentially expressed genes (DEGs) by R language. Subsequently, the DEGs were analyzed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Moreover, the protein-protein interaction (PPI) network of DEGs was analyzed by STRING database and Cytoscape. The results showed that 318 downregulated genes and 58 upregulated genes were observed in GSE7116; 690 downregulated genes and 1148 upregulated genes were screened from 34183 genes in GSE74089. The DEGs involved in progression of osteonecrosis involved inflammation, immunological rejection, and bacterial infection-related pathways. The GO enrichment showed that osteonecrosis was related with extracellular matrix, external encapsulating structure organization, skeletal system development, immune response activity, cell apoptosis, mononuclear cell differentiation, and serine/threonine kinase activity. Moreover, PPI network showed that the progression of osteonecrosis of the femoral head was related with CCND1, CDH1, ESR1, SPP1, LOX, JUN, ITGA, ABL1, and VEGF, and osteonecrosis of the jaw is related with ACTB, CXCR4, PTPRC, IL1B, CXCL8, TNF, JUN, PTGS2, FOS, and RHOA. In conclusion, this study identified the hub factors and pathways which might play important roles in progression of osteonecrosis and could be used as potential biomarkers for diagnosis and treatment of osteonecrosis.

American Association of Oral and Maxillofacial Surgeons' Position Paper on Medication-Related Osteonecrosis of the Jaws-2022 Update

Strategies for management of patients with, or at risk for, medication-related osteonecrosis of the jaws (MRONJ) - formerly referred to as bisphosphonate-related osteonecrosis of the jaws (BRONJ)-were set forth in the American Association of Oral and Maxillofacial Surgeons (AAOMS) position papers in 2007, 2009 and 2014. The position papers were developed by a committee appointed by the AAOMS Board of Trustees and comprising clinicians with extensive experience in caring for these patients, as well as clinical and basic science researchers. The knowledge base and experience in addressing MRONJ continues to evolve and expand, necessitating modifications and refinements to the previous position papers. Three members of the AAOMS Committee on Oral, Head, and Neck Oncologic and Reconstructive Surgery (COHNORS) and three authors of the 2014 position paper were appointed to serve as a working group to analyze the current literature and revise the guidance as indicated to reflect current knowledge in this field. This update contains revisions to diagnosis and management strategies and highlights the current research status. AAOMS maintains that it is vitally important for this information to be disseminated to other relevant healthcare professionals and organizations.

The preventive care of medication-related osteonecrosis of the jaw (MRONJ): a position paper by Italian experts for dental hygienists

PURPOSE

The prevention and early diagnosis of medication-related osteonecrosis of the jaw (MRONJ) is fundamental to reducing the incidence and progression of MRONJ. Many in the field believe that dental hygienists should play an integral role in primary and secondary MRONJ prevention. However, to date, very few publications in the literature have proposed standardised MRONJ protocols, which are dedicated to dental hygienists. The aim of this study was to provide guidance to the health care providers managing MRONJ.

METHODS

The expert opinion in this study was developed by dental hygienists from the main Italian technical-scientific associations (Italian Dental Hygienists Association, AIDI and National Union of Dental Hygienists, UNID) and authors of the latest Italian recommendations regarding MRONJ from the field of dentistry and maxillofacial surgery.

RESULTS

The oral care protocol outlined in this position paper is focused on the role of dental hygienist in patients at risk or affected by MRONJ, and it regards 3 main issues: primary prevention, secondary prevention and supporting the treatment of MRONJ. Each issue contains easy-to-apply indications and procedures, as described by the authors, regarding the role of the dental hygienist.

CONCLUSION

Referring to the main issues under consideration (primary prevention, secondary prevention and the treatment of MRONJ), a clinical examination of periodontal tissue is critical in preventing MRONJ. It is the opinion of the authors of this study that the application of a periodontal screening score is fundamental in defining personalised strategies for patients at risk of MRONJ. By means of these basic procedures, a protocol for assisting the health care provider and the presentation of a practical approach for patients at risk or affected by MRONJ are described in this study.

[Clinical efficacy of hydroxyapatite and tricalcium phosphate modified with hyaluronic acid in the treatment of patients with periimplantitis]

THE AIM OF THE STUDY

Was to assess the effectiveness of the use of hydroxyapatite (HAP) and tricalcium phosphate (TCF) modified with hyaluronic acid in the treatment of patients with periimplantitis.

MATERIALS AND METHODS

Clinical studies were conducted in 128 patients (44% male and 56% female) aged up to 55 years, who sought dental care with the main diagnosis of periimplant mucositis and periimplantitis. To compare the features of osseointegration of dental implants under bone remodeling three groups of patients were formed: one control and 2 main ones. In the control group the wound was managed under a blood clot, in the first main group HAP and TCF and in the second main group HAP and TCF modified with hyaluronic acid were used. X-ray examination was performed in various modes. Clinical assessment of implant stability in the operated area was carried out using subjective (percussion and palpation method) and objective method of frequency resonance analysis using the Osstell ISQ device calculating the stability coefficient of the dental implant (SCDI).

RESULTS

12 months after the periimplant zone remodeling procedure the bone resorption rates surrounding the implant were statistically significantly the lowest in the second main group (0.682±0.006 mm, p<0.001) compared with the values in the control and first main groups (1.626±0.022 and 1.025±0.034 mm, respectively). In the former groups bone resorption continued to progress during the observation period. In patients of the second main group, the average values of the SCDI for all study periods were 68.97±1.09 units which turned out to be the highest indicator and significantly differed from the values of other observation groups (p<0.05), which may be due to a tighter fit of the implants to the surface of the newly formed bone tissue.

CONCLUSION

The results of the study 12 months after the periimplant zone remodeling operation procedure prove the efficacy of HAP and TCF modified with hyaluronic acid for the treatment of patients with periimplantitis.

Medication-Related Osteonecrosis of the Jaw (MRONJ): A Review of Pathophysiology, Risk Factors, Preventive Measures and Treatment Strategies

Medication-related osteonecrosis of the jaw (MRONJ) is a major problem that can occur in people taking certain medications such bisphosphonates and denosumab. It can be used to treat osteoporosis or cancer. Bisphosphonate exposure, dental diseases and procedures, age, sex, anatomical factors, medical issues, and hereditary factors are all variables that enhance the risk of MRONJ. Even though MRONJ and antiresorptive medications have a close association, the pathophysiology of MRONJ is unknown. Careful dental preparation and oral hygiene instructions significantly minimize the risk of osteonecrosis of the jaw (ONJ). It is ideal to start antiresorptive treatment after the completion of required dental treatment; it is not contraindicated and carries low risk in patients who are on oral antiresorptive medications for less than three years. Drug holidays are one proposed solution to address MRONJ. However, there is still inadequate evidence to support their effectiveness. The objectives of this literature review are to recognize the main diagnostic principles and risk factors and to review the pathophysiology, protective procedures and treatment modalities related to MRONJ.

The following topics are covered in the review: epidemiology, diagnostic criteria, risk factors, pathogenesis and mechanism, MRONJ staging and symptoms, clinical and radiographic findings, treatment strategies, prevention and drug holiday.

Early Changes of VEGF Levels After Zoledronic Acid in Women With Postmenopausal Osteoporosis: A Potential Role of Vitamin D

Zoledronic acid (Zol) is a widely used intravenous aminobisphosphonate to treat both benign and malignant skeletal diseases, and bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side effect whose pathophysiology remains poorly understood. Vascular Endothelial Growth Factor (VEGF) has been recognized to mediate BRONJ in cancer patients undergoing Zol treatment, however data on VEGF are lacking in patients with osteoporosis. Increasing evidences demonstrate that vitamin D influences VEGF levels. The aim of this study was to investigate the influence of Zol on VEGF levels and the possible role for vitamin D on the Zol mediated changes of VEGF concentration in women with postmenopausal osteoporosis. Twenty-eight postmenopausal women with osteoporosis were enrolled and randomized into two groups to receive Zol (5 mg) or placebo. At baseline, at day-3 and day-30 VEGF serum levels were measured; bone turnover markers, 25-hydroxyvitamin D [25(OH)D] and serum calcium were evaluated at baseline. In Zol-treated women, VEGF increased significantly on day-3, and then decreased on day-30. In the Zol-treated women, the percent change of VEGF levels between baseline and day-30 (-18% at day-30 vs. baseline, p = 0.01) was significantly associated with serum 25(OH)D values (r = 0.29, p = 0.028). At a stepwise multiple regression analysis, after correcting for age, BMI, time since menopause, femoral neck BMD, osteocalcin, C-terminal telopeptide of type 1 collagen, and baseline VEGF levels, 25(OH)D levels were independently associated with VEGF change (β = 1.7, SE = 0.71, p = 0.03). For the first time, we detected early modifications of circulating VEGF in postmenopausal women receiving Zol for osteoporosis, identifying a vitamin D-dependent modulation of these changes.

Cancer Patients at Risk for Medication-Related Osteonecrosis of the Jaw. A Case and Control Study Analyzing Predictors of MRONJ Onset

The goal of this investigation was to identify potential risk factors to predict the onset of medication-related osteonecrosis of the jaw (MRONJ). Through the identification of the multiple variables positively associated to MRONJ, we aim to write a paradigm for integrated MRONJ risk assessment built on the combined analysis of systemic and local risk factors. The characteristics of a cohort of cancer patients treated with zoledronic acid and/or denosumab were investigated; beyond the set of proven risk factors a new potential one, the intake of new molecules for cancer therapy, was addressed. Registered data were included in univariate and multivariate logistic regression analysis in order to individuate significant independent predictors of MRONJ; a propensity score-matching method was performed adjusting by age and sex. Univariate logistic regression analysis showed a significant effect of the parameters number of doses of zoledronic acid and/or denosumab (OR = 1.03; 95% CI = 1.01–1.05; p = 0.008) and chemotherapy (OR = 0.35; 95% CI = 0.17–0.71; p = 0.008). The multiple logistic regression model showed that breast, multiple myeloma, and prostate cancer involved a significantly higher risk compared to lung cancer; a significant effect of the combined variables number of doses of zoledronic acid and/or denosumab (OR = 1.03; 95% CI = 1.01–1.06); p-value = 0.03) and exposure to novel molecule treatment (OR = 34.74; 95% CI = 1.39–868.11; p-value = 0.03) was observed. The results suggest that a risk assessment paradigm is needed for personalized prevention strategies in the light of patient-centered care.

Infection as an Important Factor in Medication-Related Osteonecrosis of the Jaw (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) has become a well-known side effect of antiresorptive, and antiangiogenic drugs commonly used in cancer management. Despite a considerable amount of literature addressing MRONJ, it is still widely accepted that the underlying pathomechanism of MRONJ is unclear. However, several clinical and preclinical studies indicate that infection seems to have a major role in the pathogenesis of MRONJ. Although there is no conclusive evidence for the infection hypothesis yet, available data have shown a robust association between local infection and MRONJ development. This observation is very critical in order to implement policies to reduce the risk of MRONJ in patients under antiresorptive drugs. This critical review was conducted to collect the most reliable evidence regarding the link between local infection and MRONJ pathogenesis.

Osteonecrosis of the jaw secondary to haematopoietic stem cell transplantation

Osteonecrosis of the jaw (ONJ) is necrosis of mandibular or maxillary bone, which sometimes leads to bone exposure and sequestration. There is evidence that the microenvironment of the marrow stromal system is severely and irreversibly damaged after haematopoietic stem cell transplantation (HSCT) leading to a deficit in the quantity and quality of osteoblastic progenitors, compromising the ability to regenerate a normal osteogenic cell population and abnormality in bone remodelling/turnover. While osteonecrosis of the appendicular skeleton is a common complication after HSCT, there have been no reports of an association with ONJ. This is a report of the first case of ONJ secondary to HSCT in a 69-year-old woman who developed a unique pattern of osteonecrosis involving all four quadrants of the jaw 2 months after allogeneic stem cell transplantation.

Osteoporosis: Current and Emerging Therapies Targeted to Immunological Checkpoints

Osteoporosis is a skeletal pathology characterized by compromised bone strength leading to increased risk of fracture, mainly the spine and hip fractures. Osteoporosis affects more than 200 million people worldwide and because of the skeletal fractures it causes, represents a major cause of morbidity, disability and mortality in older people. Recently, the new discoveries of osteoimmunology have clarified many of the pathogenetic mechanisms of osteoporosis, helping to identify new immunological targets for its treatment opening the way for new and effective therapies with biological drugs. Currently, there are basically two monoclonal antibodies for osteoporosis therapy: denosumab and romosozumab. Here, we focus on the modern approach to the osteoporosis management and in particular, on current and developing biologic drugs targeted to new immunological checkpoints, in the landscape of osteoimmunology.

Medication-related osteonecrosis of the jaw: Analysing the range of implicated drugs from the Australian database of adverse event notifications

AIMS

Medication-related osteonecrosis of the jaw (MRONJ) is an uncommon but potentially debilitating condition, characterised by nonhealing jawbone, with or without mucosal exposure, in the presence of certain drugs. Those already strongly associated with MRONJ include antiresorptives denosumab and bisphosphonates; however, a growing range of other non-antiresorptive drugs is implicated. The aim of this study was to analyse all case reports of MRONJ submitted to the publicly available Database of Adverse Event Notification from the Therapeutic Goods Administration in Australia.

METHODS

The Therapeutic Goods Administration was contacted on 6 January 2020 and asked for all reports containing the words "osteonecrosis of the jaw". This was provided in a spreadsheet of de-identified reports received from commencement of the database in 1971 until 1 October 2019.

RESULTS

The drugs implicated in the 419 cases were divided by established drugs with MRONJ and secondary drugs that possibly contribute to MRONJ development. While the majority of cases were associated with denosumab or bisphosphonates (n = 405), there were 14 reports where secondary agents that directly or indirectly affect bone turnover, were also implicated. Some of these secondary drugs, including adalimumab, etanercept, methotrexate and rituximab have previously been associated with MRONJ in published case reports.

CONCLUSIONS

This study contributes to the sparse but growing literature associating an increasing number of drugs with MRONJ, and underscores the importance of considering all possible drugs that elevate a patient's MRONJ risk.

Combined Administration of Bisphosphonates, Chemotherapeutic Agents, and/or Targeted Drugs Increases the Risk for Stage 3 Medication-Related Osteonecrosis of the Jaw: A 4-Year Retrospective Study

Objectives

Patients with stage 3 medication-related osteonecrosis of the jaw (MRONJ) suffer from severe complications. Chemotherapeutic agents and targeted drugs are considered to be associated with the development of MRONJ. However, little is known regarding the association of those agents with stage 3 MRONJ. The purpose of this study is to analyze the comprehensive medication history of patients with advanced-stage MRONJ (stage 2 and stage 3) and evaluate the possible risk factors for stage 3 MRONJ. Patients and Methods. Sixty patients with advanced-stage MRONJ were involved in this retrospective study. Patients with developmental maxillofacial anomalies, previous radiation in the head and neck areas, and jaw bone tumors were excluded from the study. All patients were divided into two groups by their MRONJ stage (stage 2 or stage 3). Demographic and clinical characteristics, comprehensive medication data (bisphosphonates, chemotherapeutic agents, targeted drugs, and immunosuppressive agents), and results of serological biomarkers were recorded and compared between two groups. Univariate and multivariate logistic regressions were performed by SPSS 25.0 for evaluating risk factors of stage 3 MRONJ.

Results

Our results indicate that chemotherapy (adjusted OR = 3.43; 95% CI: 1.03 to 11.38), targeted drugs (adjusted OR = 3.69; 95% CI: 1.06 to 12.80), and maxillary lesions (adjusted OR = 4.26; 95% CI: 1.19 to 15.23) increase the risk of stage 3 MRONJ.

Conclusion

The outcome of this study justifies that chemotherapeutic agents and targeted drugs are probably risk factors for stage 3 MRONJ. In addition, the osteonecrosis in maxilla is more easily to develop into stage 3 MRONJ. Intense clinical observation is recommended in MRONJ patients with maxillary osteonecrosis and in those who concurrently administered bisphosphonates, chemotherapeutic agents, and/or targeted drugs. This trial is registered with ChiCTR2000032428.

Medication-Related Osteonecrosis of Jaws (MRONJ) Prevention and Diagnosis: Italian Consensus Update 2020

The Medication-Related Osteonecrosis of Jaws (MRONJ) diagnosis process and its prevention play a role of great and rising importance, not only on the Quality of Life (QoL) of patients, but also on the decision-making process by the majority of dentists and oral surgeons involved in MRONJ prevention (primary and secondary). The present paper reports the update of the conclusions from the Consensus Conference-held at the Symposium of the Italian Society of Oral Pathology and Medicine (SIPMO) (20 October 2018, Ancona, Italy)-after the newest recommendations (2020) on MRONJ were published by two scientific societies (Italian Societies of Maxillofacial Surgery and Oral Pathology and Medicine, SICMF and SIPMO), written on the inputs of the experts of the Italian Allied Committee on ONJ (IAC-ONJ). The conference focused on the topic of MRONJ, and in particular on the common practices at risk of inappropriateness in MRONJ diagnosis and therapy, as well as on MRONJ prevention and the dental management of patients at risk of MRONJ. It is a matter of cancer and osteometabolic patients that are at risk since being exposed to several drugs with antiresorptive (i.e., bisphosphonates and denosumab) or, more recently, antiangiogenic activities. At the same time, the Conference traced for dentists and oral surgeons some easy applicable indications and procedures to reduce MRONJ onset risk and to diagnose it early. Continuous updating on these issues, so important for the patient community, is recommended.

Clinical profile of individuals with bisphosphonate-related osteonecrosis of the jaw: an integrative review

BACKGROUND

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is still the most prevalent type of osteonecrosis with clinical relevance. In Brazil, bisphosphonate use is high but there is a lack of epidemiological studies on BRONJ.

OBJECTIVE

To determine the clinical profile of BRONJ in a Brazilian population through an integrative review.

DESIGN AND SETTING

Integrative review of BRONJ in a Brazilian population.

METHODS

Cases and clinical research on Brazilians with BRONJ between 2010 and 2019, indexed in PubMed/MEDLINE, Scopus, Web of Science and LILACS were reviewed. Age, sex, type and time of bisphosphonate intake, administration route, related diseases, region of the BRONJ, diagnostic criteria, staging, triggering factor and type of treatment were analyzed.

RESULTS

Fifteen articles on 128 subjects were included. Most patients were women (82.03%); the mean age was 63 years. Intravenous zoledronic acid was mostly used (62.50%), for breast cancer treatment (46.87%). The main localization of BRONJ was the mandible (54.68%), associated mainly with tooth extractions (45.98%). The diagnostic criteria were clinical (100%) and radiographic (89.06%), mostly in stage II (68.08%). The surgical treatments were sequestrectomy (37.50%) and platelet-rich plasma (PRP) (36.71%). Microbial control was done using chlorhexidine (93.75%) and infection control using clindamycin (53.90%).

CONCLUSIONS

BRONJ had higher prevalence in Brazilian women receiving treatment for breast cancer and osteoporosis. The mandible was the region most affected with a moderate stage of BRONJ, particularly when there were histories of tooth extraction and peri-implant surgery. Sequestrectomy with additional drugs and surgical therapy was the treatment most accomplished.

Platelet-Rich Plasma (PRP) in Dental Extraction of Patients at Risk of Bisphosphonate-Related Osteonecrosis of the Jaws: A Two-Year Longitudinal Study

Dental extraction has often been described as the main trigger event of osteonecrosis of the jaws (ONJ). This longitudinal hospital-based study aimed to evaluate the outcome at 2 years of a standardized medical-surgical protocol for dental extraction, combined with platelet rich-plasma (PRP) application, compared with conventional protocol not combined with PRP or any other autologous platelet concentrate in cancer (ONC) and osteometabolic (OST) patients, at risk of bisphosphonate (BP)-related ONJ. Twenty patients were consecutively recruited: six received BPs for cancer skeletal-related events (34.17 ± 19.97 months), while fourteen received BPs for metabolic bone disease (74.5 ± 34.73 months). These patients underwent a standardized protocol for dental extraction, combined with autologous PRP application in the post-extraction socket. A total of 63 dental extractions were performed (24 and 39 in ONC and OST groups, respectively). As controls, historical cases, derived from the literature and including 171 ONC and 734 OST patients, were considered. The outcome of the surgical treatment was successful in all patients treated with PRP: two years after extraction, no patient had clinical or radiological signs of ONJ. When this datum was compared with historical controls, no statistically significant differences were found (p > 0.1). The combination of a standardized medical-surgical protocol with PRP application may contribute to limit the occurrence of BP-related ONJ, in both ONC and OST patients. Additional prospective studies with a larger patient sample are necessary to confirm this datum.

Pain characteristics in medication-related osteonecrosis of the jaws

PURPOSE

To characterise pain from medication-related osteonecrosis of the jaws (MRONJ) and the effects of antimicrobial treatment on it.

METHODS

Data from files of patients diagnosed with MRONJ according to the position paper of the American Association of Oral and Maxillofacial Surgeons (2014) and Multinational Association of Supportive Care in Cancer and American Society of Clinical Oncology (2019) were collected retrospectively, including gender, age, primary disease, bone-modifying agents (BMAs)/anti-angiogenics, administration route, involved jaw, location, and exposure size. The patients were treated according to the abovementioned position papers' recommendations, i.e. all patients who suffered from pain were staged as 2 or 3 and treated with systemic amoxicillin, or doxycycline or clindamycin in case of sensitivity, and local antiseptic and hygiene instructions.

RESULTS

Data from 77 MRONJ patients (aged 65.09 ± 11.9 years old) were analysed. Most (90.1%) received bisphosphonates for cancer (79%) and osteoporosis (17%). A total of 67.5% experienced pain; 36.5% had moderate-to-severe pain. Female gender was significantly associated with the presence of pain (p = 0.002). Osteonecrosis lesions after dento-alveolar surgery had a higher risk of pain development than spontaneous lesions (p = 0.045). Medical and oncologic background, type of pharmacotherapy, lesion size, and location were not associated with pain levels. Worse initial pain was significantly associated with better relief following MRONJ treatment (p = 0.045). Meaningful pain reduction (≥ 50%) was significantly correlated with initial pain severity (p = 0.0128, OR = 4.75).

CONCLUSIONS

Pain from infection and inflammation often accompanies MRONJ. The presence of pain is correlated with longer BMAs pre-therapy and if surgery preceded the MRONJ. Persistency of the mild pain together with a resistance to common antimicrobial treatment, although not complete, is a feature that MRONJ pain shares with neuropathic-"like" pain, and requires further study and consideration during treatment.

Awareness among patient at risk of developing Medication Related Osteonecrosis of the Jaw (MRONJ) - A primary prevention strategy

The quality of life, in itself, in cancer patients or in osteoporotic individuals, without even considering the side effects of the medication in the first place, has a considerable negative impact on the clinical outcome. The Medication Related Osteonecrosis of the Jaw (MRONJ), in the maxillofacial region, although rare, needs to be addressed with the prime importance. One of the key components of any given preventive treatment strategy is to, create awareness about the medication related unwanted effects, among health care professionals and patients.

Objective

This study is aimed to explore and assess the awareness level among dental patients about MRONJ, the risk factors, and the high-risk category (who are prone to develop MRONJ).

Material and methods

This is a prospective interviewer administered research electronic data capture (REDCap) survey. The sample included 68 patients, who are currently taking or will be taking Bisphosphonate (BP), and/or Denosumab, and anti-Angiogenic agent. Data have been analyzed using IBM SPSS software,

Results

Sixty-eight patients (18 males and 50 females), participated in this study. Only 23 subjects (33.82%) were aware about the MRONJ. Females were more aware about the complications than males. The awareness among the subjects with education at college level appears to be higher than the subjects having education less than high school level. Even though, a dental check- up, is mandatory, prior to starting these medications, to see if any dental treatment is required, only slightly more than half of the patients (54.72%) had a dental checkup.

Conclusion

This is a novel study in the Middle- East, used to assess awareness about the MRONJ including three type of related medications. Low awareness of MRONJ is alarming. The results of the study will help to initiate the process of providing the education materials, about the side effects and importance of oral hygiene maintenance, giving priority to improve the quality of life in such patients. Awareness of patients regarding the complications must be an important part of health care practice guidelines.

Everolimus-induced osteonecrosis of the jaw in the absence of bisphosphonates: a case report

Osteonecrosis of the jaw (ONJ) is a rare, but severe, condition that has traditionally been associated with the use of bisphosphonates. We report what is, to our knowledge, the first case of ONJ secondary to the use of everolimus, in the absence of treatment with bisphosphonates in a 65-year-old man who was given it for immunosuppression after a renal transplant. After 18 months of treatment, he was diagnosed with severe ONJ and underwent radical debridement of the palate and complete dental clearance of the maxilla.

[Progress on medication-related osteonecrosis of the jaw]

Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication of bisphosphonates (BPs) or other targeted agent therapies. MRONJ appears as exposed bone, pus, and swelling in the oral and maxillofacial regions. However, neither surgery nor conservative therapy can eliminate symptoms thoroughly. In addition to BPs, several antiresorptive and antiangiogenic agents, such as denosumab and bevacizumab, as well as targeted agents, such as sunitinib and temsirolimus, can cause osteonecrosis of  the  jaw according to the literature. This review aims to summarize the research progress on these new drugs.

Association between biomarkers and medication-related osteonecrosis of the jaws: a systematic review

OBJECTIVES

Our aim was to conduct a systematic review (SR) of the literature assessing the role of human biomarkers in the diagnosis or prognostication of medication-related osteonecrosis of the jaws (MRONJ).

STUDY DESIGN

An electronic search without date or language restriction was carried out in PubMed/MEDLINE, the Cochrane Central Register of Controlled Trials, Web of Science, and LILACS for publications until March 2018. In addition, a manual search in the gray literature was conducted. The search process was performed by 2 independent reviewing authors. Eligibility criteria included randomized and nonrandomized clinical trials, prospective or retrospective cohorts, case controls, and case series evaluating the association between biomarkers and MRONJ. The protocol of this SR was registered in PROSPERO under number CRD42018095886.

RESULTS

The search and selection process yielded 19 studies (2 case series, 6 case-control studies, 9 prospective cohort studies, and 2 retrospective studies) published between 2008 and 2018. Twenty-four biomarkers collected from serum, saliva, and urine were investigated by these studies. Eleven biomarkers were possibly related to MRONJ; however, no consensus is observed in the literature with regard to the sensitivity and clinical effectiveness of these biomarkers.

CONCLUSIONS

Although many biomarkers have been associated with MRONJ, the present SR found scarce clinical evidence supporting the use of these biomarkers for the diagnosis and prognosis of MRONJ.

Zoledronate treatment duration is linked to bisphosphonate-related osteonecrosis of the jaw prevalence in rice rats with generalized periodontitis

OBJECTIVES

To determine the extent that zoledronate (ZOL) dose and duration is associated with bisphosphonate-related osteonecrosis of the jaw (BRONJ) prevalence in rice rats with generalized periodontitis (PD), characterize structural and tissue-level features of BRONJ-like lesions in this model, and examine the specific anti-resorptive role of ZOL in BRONJ.

MATERIALS AND METHODS

Rice rats (n = 228) consumed high sucrose-casein diet to enhance generalized PD. Groups of rats received 0, 8, 20, 50 or 125 µg/kg IV ZOL/4 weeks encompassing osteoporosis and oncology ZOL doses. Rats from each dose group (n = 9-16) were necropsied after 12, 18, 24 and 30 weeks of treatment. BRONJ-like lesion prevalence and tissue-level features were assessed grossly, histopathologically and by MicroCT. ZOL bone turnover effects were assessed by femoral peripheral quantitative computed tomography, serum bone turnover marker ELISAs and osteoclast immunolabelling.

RESULTS

Prevalence of BRONJ-like lesions was significantly associated with (a) ZOL treatment duration, but plateaued at the lowest oncologic dose, and (b) there was a similar dose-related plateau in the systemic anti-resorptive effect of ZOL. ZOL and BRONJ-like lesions also altered the structural and tissue-level features of the jaw.

CONCLUSION

The relationship between BRONJ-like lesion prevalence and ZOL dose and duration varies depending on the co- or pre-existing oral risk factor. At clinically relevant doses of ZOL, BRONJ-like lesions are associated with anti-resorptive activity.

Increased risk of bisphosphonate-related osteonecrosis of the jaw in patients with Sjögren's syndrome: nationwide population-based cohort study

OBJECTIVE

The aim of this study was to explore whether patients with Sjögren's syndrome (SS) were susceptible to bisphosphonate (BP)-related osteonecrosis of the jaw (BRONJ) after tooth extraction in the entire population of Taiwan.

DESIGN

A nationwide population-based retrospective cohort study.

SETTING

Data were extracted from Taiwan's National Health Insurance Research Database (NHIRD).

METHODOLOGY

Medical conditions for both the study and control group were categorised using the International Classification of Diseases, 9th Revision. ORs and 95% CIs for associations between SS and osteonecrosis of the jaw (ONJ) were estimated using Cox regression.

RESULTS

Overall, 13 398 patients diagnosed with SS were identified from the NHIRD. An additional 53 592 matched patients formed the control group. At the 3-year follow-up, patients with SS started to exhibit a significantly increased cumulative risk of developing BRONJ compared with that of patients without SS (log rank test <0.001). At the end of the follow-up period, patients with SS exhibited a significantly increased incidence of ONJ compared with that of the controls (0.08%vs0.03%, p=0.017). The Cox regression model showed that patients with SS also exhibited a significantly increased risk of developing BRONJ compared with that of the patients without SS (adjusted HR=7.869, 95% CI 3.235 to 19.141, p<0.001).

CONCLUSION

Patients with SS exhibit an increased risk of developing BRONJ after tooth extraction. BPs should be used with caution in patients with SS.

Epidermal Growth Factor Reverses the Inhibitory Effects of the Bisphosphonate, Zoledronic Acid, on Human Oral Keratinocytes and Human Vascular Endothelial Cells In Vitro via the Epidermal Growth Factor Receptor (EGFR)/Akt/Phosphoinositide 3-Kinase (PI3K) Signaling Pathway

Background

Medication-related osteonecrosis of the jaw (MRONJ) is due to the direct effects of drug toxicity and the effects on angiogenesis. The aims of this study were to evaluate the effects of treatment with the bisphosphonate, zoledronic acid, on human oral keratinocytes (HOKs) and human umbilical vein endothelial cells (HUVECs) in vitro, and whether epidermal growth factor (EGF) could alter these effects.

Material/Methods

HOKs and HUVECs were incubated with zoledronic acid or EGF. Cell viability was assessed by the cell counting kit-8 (CCK-8), cell apoptosis was studied using Annexin-V conjugated to fluorescein isothiocyanate (FITC). Angiogenesis was studied by observing HUVEC tube formation and cell migrations using a transwell assay. A scratch wound assay investigated cell migration of HOKs. Western blot measured expression levels of phosphorylated epidermal growth factor receptor (EGFR), Akt, phosphoinositide 3-kinase (PI3K), the mechanistic target of rapamycin (mTOR), and endothelial nitric oxide synthase (eNOS).

Results

Zoledronic acid treatment (5 μmol/L) significantly inhibited cell viability and cell migration of HOKs and HUVECs and angiogenesis of HUVECS (P<0.05); EGF partially reversed these effects (P<0.05). Zoledronic acid treatment of HOKs and HUVECs had no significant effects on apoptosis (P>0.05), but significantly reduced expression levels of p-EGFR, p-Akt, p-PI3K, p-mTOR), and p-eNOS (P<0.05); EGF partially reversed these effects and increased the expression levels (P<0.05).

Conclusions

EGF partially reversed the effects of the bisphosphonate, zoledronic acid, on HOKs and HUVECs in vitro via the EGFR/Akt/PI3K signaling pathway. Further studies are required to determine the effects of EGF on MRONJ including bisphosphonate-related osteonecrosis of the jaw.

Medication-related osteonecrosis of the jaw unrelated to bisphosphonates and denosumab-a review

The link between medication-related osteonecrosis of the jaw (MRONJ) and bone modulating drugs, such as bisphosphonates and denosumab, is well established, and the number of reported cases is increasing. The development of novel medications used in the treatment of cancer, as well as autoimmune and bone conditions, has led to more cases of MRONJ being reported. However, in addition to this group of medications, increasing numbers of new agents in cancer therapy, such as antiangiogenic agents, have also been implicated in the development of MRONJ. As these newer agents with similar mechanisms are routinely used, the numbers of reported cases will likely rise further. This article aims to identify and summarize the drugs implicated in MRONJ, besides bisphosphonates and denosumab. A wide range of medications classified as tyrosine kinase inhibitors, monoclonal antibodies, mammalian target of rapamycin inhibitors, radiopharmaceuticals, selective estrogen receptor modulators, and immunosuppressants have been implicated in MRONJ. It remains crucial that oral health care providers are aware of these new medications and their associated risks to manage their patients appropriately.

Osteonecrosis of the jaw related to non-antiresorptive medications: a systematic review

INTRODUCTION

The reporting of osteonecrosis of the jaw (ONJ) related to anticancer agents without known antiresorptive properties (non-antiresorptives), such as antiangiogenics, tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, immune checkpoint inhibitors, and cytotoxic chemotherapy is increasing.

OBJECTIVE

To review characteristics of ONJ in cancer patients receiving non-antiresorptives.

METHODS

A systematic review of the literature between 2009 and 2017 was conducted by the Bone Study Group of MASCC/ISOO.

RESULTS

Of 6249 articles reviewed and from personal communication, 42 ONJ cases related to non-antiresorptives were identified. No gender predilection was noted. Median age was 60 years and ONJ stage 2 was most common, with predilection for posterior mandible. Exposed bone, pain, and infection were common at diagnosis. In comparison to bone targeting agents (BTAs), radiology, histology, and management were similar, with medication often discontinued. Delayed diagnosis (median 8 weeks) was noted. Important differences included earlier time to ONJ onset (median 20 weeks), absence of trigger event (40%), and greater likelihood of healing and shorter healing time (median 8 weeks) as compared to BTA-related ONJ. Gastrointestinal cancers predominated, followed by renal cell carcinomas compared to breast, followed by prostate cancers in BTA-related ONJ, reflecting different medications.

CONCLUSIONS

Data about non-antiresorptive-related ONJ is sparse. This type of ONJ may have better prognosis compared to the BTA-related ONJ, suggested by greater likelihood of healing and shorter healing time. However, the delay in diagnosis highlights the need for more education. This is the first attempt to characterize ONJ associated with different non-antiresorptives, including BRAF and immune checkpoint inhibitors.

Treatment of Medication-Related Osteonecrosis of the Jaw and its Impact on a Patient's Quality of Life: A Single-Center, 10-Year Experience from Southern Italy

INTRODUCTION

No official guidelines are available for the management of medication-related osteonecrosis of the jaw (MR-ONJ). The additional benefit of surgery after pharmacological treatment is debated by both clinicians and patients.

OBJECTIVE

The aim of this study was to evaluate the changes in patients' MR-ONJ-related quality of life (QoL) after pharmacological treatment with or without surgery in a large cohort affected by MR-ONJ.

METHODS

Anonymized data on patients diagnosed with MR-ONJ were extracted from the database of the Osteonecrosis of the Jaw Treatment Center (University of Messina, Italy) in the years 2005-2015. QoL was evaluated at the moment of MR-ONJ diagnoses (T0), after pharmacological treatment with or without surgery (T1 and T2, respectively), based on scores from the European Organisation for Research and Treatment of Cancer (EORTC) QOL Module for Head and Neck Cancer (global oral health status [GOHS]) and a visual analog scale (VAS), stratified by indication for use.

RESULTS

Among 100 patients, 36% were affected by osteoporosis (OSTEO group) and 64% were affected by cancer (ONC group). Considering T0, QoL scores were higher in the OSTEO group then in the ONC group. At T1, GOHS and VAS increased in both groups (OSTEO group: +9.9% and +39.9%; ONC group: +35.4 and +97.2%, respectively). Pharmacological treatment was effective in reducing pain (OSTEO group: -22.0%; ONC group: -44.8%), and social contact troubles (OSTEO group: -40.3%; ONC group: -26.7%). At T2, GOHS and VAS further increased. Scores related to 'pain' and the troubles related to the 'social dimension' also decreased (OSTEO group: -91.3% and -72.0%; ONC group: 50.8% and -16.4%, respectively).

CONCLUSIONS

MR-ONJ-related QoL increased after pharmacological treatment and, more notably, after surgery, which may offer benefits to selected patients. QoL data may help clinicians in promoting tailored management of MR-ONJ.

The Dental Management of Patients at Risk of Medication-Related Osteonecrosis of the Jaw: New Paradigm of Primary Prevention

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse reaction of antiresorptive and antiangiogenic agents; it is a potentially painful and debilitating condition that can considerably affect the quality of life of patients. Furthermore, even if its epidemiology and pathogenesis have still not been fully clarified, several risk factors related to MRONJ have been recognized in prevention protocols. Three main risk factors are as follows: (i) the type of ONJ-related medications: antiresorptive (e.g., Bisphosphonates, Denosumab) and antiangiogenic drugs (e.g., Bevacizumab, Sunitinib); (ii) the category of patient at MRONJ risk: cancer versus non-cancer patient; (iii) the typologies and timing of dental treatments (e.g., before, during, or after the drug administration). The aim of this paper is to describe the new paradigm by the Italian Society of Oral Pathology and Medicine (SIPMO) on preventive dental management in patients at risk of MRONJ, prior to and during/after the administration of the aforementioned ONJ-related drugs. In reducing the risk of MRONJ, dentists and oral hygienists are key figures in applying a correct protocol of primary prevention for pre-treatment and in-treatment patients. However, the necessity of a multidisciplinary standardized approach, with a sustained dialogue among specialists involved, should be always adopted in order to improve the efficacy of preventive strategies and to ameliorate the patient's quality of life.

Exosomes: novel regulators of bone remodelling and potential therapeutic agents for orthodontics

Recent studies suggest that exosomes are involved in intercellular communication required for the maintenance of healthy bone. Exosomes are small (30-150 nm in diameter) extracellular vesicles that are formed in multivesicular bodies and are released from cells as the multivesicular bodies fuse with the plasma membrane. Regulatory exosomes have the capacity to exert profound control over target cells. They can stimulate plasma membrane receptors and are also internalized by the target cell delivering proteins, lipids, small molecules and functional RNAs from the cell of origin. We and others have recently reported on regulatory exosomes from osteoclasts and osteoblasts. Key candidate molecules identified in exosome-based regulation of bone remodelling include receptor activator of nuclear factor kappa B (RANK), RANK-ligand (RANKL), ephrinA2, semaphorin 4D, microRNA-146a and microRNA- 214-3p. Exosomes will likely prove to be crucial elements in the communication networks integrating bone cells (osteoclasts, osteoblasts, osteocytes) and linking bone to other tissue. Exosomes collected from bone cells grown in culture may prove useful to augment bone remodelling associated with orthodontic force application or required for the repair of craniofacial bone. Various technologies allow exosomes to be engineered to improve their targeting and efficacy for therapeutic purposes. In summary, exosomes have emerged as important elements of the machinery for intercellular communication between bone cells. They hold great promise as therapeutic targets, biomarkers and therapeutic agents for orthodontists.

Could the Combined Administration of Bone Antiresorptive Drug, Taxanes, and Corticosteroids Worsen Medication Related Osteonecrosis of the Jaws in Cancer Patients?

The study presents a report of 58 metastatic cancer patients who developed osteonecrosis of the jaws after being treated with zoledronic acid and taxanes, plus corticosteroids. A retrospective analysis of data registered in the archives of two Italian osteonecrosis of the jaws treatment centers, who are based at the University of Messina and at the University of Palermo, was performed in order to study, in these patients, demographic data and characteristics such as frequency of cancer location, lines of therapy, frequency of cancer drugs, presence/absence of oral trigger, number, location, and stage of jaw osteonecrosis. It was found that the majority of patients developed advanced stages of osteonecrosis, frequently complicated with infection. It was hypothesized that the concurrent administration of chemotherapeutic agents could be eventually considered as a factor able to allow a faster worsening of the clinical manifestation through the exacerbation of soft tissue defects, due to chemotherapy drugs.

Osteonecrosis of the Jaw Associated with Antiangiogenics in Antiresorptive-Naïve Patient: A Comprehensive Review of the Literature

Objectives

To review the available literature on medication-related osteonecrosis of the jaw (MRONJ) associated with antiangiogenics in antiresorptive-naïve individuals.

Methods

A literature search was performed using MEDLINE via PubMed, EMBASE, and Web of Science in December 2017.

Results

We identified reports describing a total of 35 antiresorptive drugs-naïve patients who developed antiangiogenic-related MRONJ. The mean age of these patients was 59.06 years and the F : M ratio was 4 : 5. The most common underlying disease was metastatic renal cell cancer. Pain to the mandible was the most common complaint (34.29%) and the majority of patients presented with bone exposure. The mean duration of intravenous and oral antiangiogenics before MRONJ development was 6.5 and 16.72 months, respectively. The most common additional risk factor was dental extraction (37.14%). Almost half of the MRONJ patients (48.57%) received surgical treatment. 18 patients (62.06%) were reported to have disease resolution within an average time of 6.75 months.

Conclusion

MRONJ associated with antiangiogenic therapy in antiresorptive-naïve patients is a rare but potentially serious adverse effect. Available data suggests that there might be notable differences between MRONJ associated with antiangiogenics and antiresorptives; however, further prospective well-designed studies are required.

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.

Zoledronic acid increases the prevalence of medication-related osteonecrosis of the jaw in a dose dependent manner in rice rats (Oryzomys palustris) with localized periodontitis

OBJECTIVE

Investigate role of dose/duration of zoledronic acid (ZOL), a powerful anti-resorptive (pAR), on prevalence of medication-related osteonecrosis of the jaw (MRONJ) in rice rats (Oryzomys palustris), a species with natural susceptibility to food impaction-induced localized periodontitis (FILP). We hypothesize that ZOL induces MRONJ lesions in rice rats with FILP, and that the prevalence of MRONJ rises with increasing dose and duration of ZOL treatment.

METHODS

We performed a toxicology experiment with clinically-relevant doses of ZOL in female rats (N=230) fed standard (STD) rodent chow. At age 4weeks (baseline), 12 rats were necropsied. The rest were randomized into five groups that began to receive 0, 8, 20, 50 or 125μg/kg ZOL IV/q 4weeks. After 12, 18, 24 and 30weeks, subgroups (N=9-16) from each of the dose groups were necropsied. High-resolution macroscopic photos of all jaw quadrants were given a gross quadrant grade (GQG) (0-4 or MRONJ) that classified FILP lesion severity and determined presence of gross MRONJ. Quadrants with GQG≥1 were examined histopathologically. Logistic regression analysis (ZOL dose/duration) of MRONJ prevalence was completed.

RESULTS

We found: 1) 75% of 0μg/kg ZOL rats developed FILP lesions; 2) baseline rats and rats treated with 0μg/kg ZOL had no MRONJ; 3) 29 gross MRONJ cases were identified; 4) all gross MRONJ cases were confirmed histopathologically by the observation of exposed necrotic bone, and 53 new cases were discovered (total=82); 5) ZOL dose (P<0.001), but not duration (P=0.326), was a significant predictor of MRONJ prevalence; 6) 13% prevalence of gross MRONJ among all rats, with 22% prevalence among rats exposed to ZOL oncologic doses (20-125μg/kg); 7) 38% prevalence of histopathologic MRONJ among all rats, with 73% prevalence among rats exposed to ZOL oncologic doses.

CONCLUSIONS

This is the first experiment to show a dose response relationship between clinically relevant doses of ZOL and MRONJ prevalence.

Medication related osteonecrosis of the jaws associated with targeted therapy as monotherapy and in combination with antiresorptives. A report of 7 cases from the Copenhagen Cohort

OBJECTIVE

The aim of this study was to report cases of medication-related osteonecrosis of the jaws (MRONJ) associated with targeted therapy (TT) with or without concomitant antiresorptive treatment, among the Copenhagen ONJ cohort, which includes all consecutive cases of MRONJ seen in Copenhagen.

STUDY DESIGN

We retrospectively studied the treatment of 204 consecutive patients with MRONJ, seen between January 2010 and May 2016, to identify those associated with TT.

RESULTS

We detected 7 cases of MRONJ associated with TT (3.4%). Four patients received TT only, whereas 3 were concomitantly treated with bisphosphonates (n = 3) and/or denosumab (n = 3). The TT regimens included sunitinib (Sutent) (n = 1), everolimus (Afinitor) (n = 1), erlotinib (Tarceva) (n = 1), bevacizumab (Avastin) (n = 3), dasatinib (Sprycel) (n = 1) and imatinib (Glivec) (n = 1). The MRONJ stage included stages 1 and 2, and mean score on the visual analogue scale for pain in the jaw was 4.0.

CONCLUSIONS

Health care providers should be aware of the possibility of MRONJ associated with the TT agents sunitinib, everolimus, and dasatinib and uncommon cancer types, including renal cell carcinoma, non-small-cell lung cancer, glioblastoma, and leukemia, where MRONJ may also occur.

Serum levels of RANKL and OPG, and the RANKL/OPG ratio in bisphosphonate-related osteonecrosis of the jaw: Are they useful biomarkers for the advanced stages of osteonecrosis?

Background

We determined whether serum levels of Receptor Activator for Nuclear Factor κ B Ligand (RANKL), Osteoprotegerin (OPG), and the RANKL/OPG ratio could be useful biomarkers for the severity of oral lesions in bisphosphonate-related osteonecrosis of the jaw (BRONJ).

Material and Methods

A case-control study in which Group 1 consisted of 41 patients with BRONJ due to intravenous bisphosphonates, and Group 2 consisted of 44 healthy control cases. The plasma levels of RANKL and OPG were analyzed by an ELISA assay. The OPG/RANKL ratio was also calculated. We determined if the mean serum values differed among the different stages of BRONJ.

Results

Serum levels of RANKL were lower in Group 1 than in Group 2 (p =0.01), and serum levels of OPG were higher in patients with BRONJ than in the controls (p =0.006). The ratio of RANKL/OPG was greater in the controls than in Group 1 (P >0.01). There were no significant differences in the serum levels of RANKL and OPG among the different stages of osteonecrosis (P > 0.05).

Conclusions

Serum levels of RANKL and OPG, and the RANKL/OPG ratio were not valuable biomarkers for determining the severity of oral lesions in patients with BRONJ.

Key words:Bisphosphonates, RANKL, OPG, Osteonecrosis.

A Case of Pentastomiasis at the Left Maxilla Bone in a Patient with Thyroid Cancer

Pentastomiasis, a zoonotic parasite infection, is typically found in the respiratory tract and viscera of the host, including humans. Here, we report for the first time an extremely rare case of intraosseous pentastomiasis in the human maxilla suffering from medication related osteonecrosis of the jaw (MRONJ). A 55-year-old male had continuously visited the hospital for MRONJ which had primarily developed after bisphosphonate and anti-neoplastic administration for previous bone metastasis of medullary thyroid cancer. Pain, bone exposure, and pus discharge in the right mandible and left maxilla were seen. Osteolysis with maxillary cortical bone perforation at the left buccal vestibule, palate, nasal cavity, and maxillary sinus was observed by radiologic images. A biopsy was done at the left maxilla and through pathological evaluation, a parasite with features of pentastome was revealed within the necrotic bone tissue. Further history taking and laboratory evaluation was done. The parasite was suspected to be infected through maxillary open wounds caused by MRONJ. Awareness of intraosseous pentastomiasis should be emphasized not to be missed behind the MRONJ. Proper evaluation and interpretation for past medical history may lead to correct differential diagnosis and therapeutic intervention for parasite infections.

Oral mucosal changes induced by anticancer targeted therapies and immune checkpoint inhibitors

Development of biological targeted therapies and immune checkpoint inhibitors has redefined the treatment for many cancers; however, the increasing use of new protocols has led to physicians observing a new spectrum of toxicities. To date, oral adverse events induced by these new anticancer therapies have been mainly reported using nonspecific terminology ("stomatitis," "mucosal inflammation," "mucositis") and remain poorly characterized, with the exception of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis. Oral toxicities of targeted therapies often display very characteristic features which clearly differ from classic oral injuries observed with cytotoxic chemotherapy and/or radiotherapy. In addition, they frequently affect more than 20% of treated patients and can lead to a significant morbidity or permanent treatment discontinuation. Oral mucosal toxicities described in this review include mTOR inhibitor-associated stomatitis (mIAS); stomatitis, benign migratory glossitis, and osteonecrosis of the jaw associated with multi-targeted kinase inhibitors of the VEGF and PDGF receptors; mucositis induced by EGFR inhibitors (in monotherapy or in combination with head and neck radiotherapy and/or chemotherapy); hyperkeratotic lesions with BRAF inhibitors; pigmentary changes and lichenoid reactions secondary to imatinib; and more recent data on the "Osler-Weber-Rendu-like syndrome" described with the antibody-drug conjugate, TDM-1. Finally, we provide, to our knowledge, the first available structured data on oral toxicities induced by the new recently FDA- and EMA-approved monoclonal antibodies targeting PD-1. Clinical management of these targeted therapy-related oral changes is also discussed.

Adjudication of osteonecrosis of the jaw in phase III randomized controlled trials of denosumab: a systematic review

PURPOSE

Denosumab (an anti RANKL antibody) is known to be associated with an increased risk for osteonecrosis of the jaw (ONJ). Due to the variety of clinical presentation, many ONJ definitions are used. Evaluation of ONJ's frequency during phase III randomized controlled trials (RCTs) is crucial to assess benefit-risk ratio. We verified that phase III RCTs involving denosumab reported the definition of ONJ used.

METHODS

We systematically searched in Central, Medline, Cochrane, and Scopus, until 31 August 2015. We included original phase III RCTs, involving denosumab. Post hoc analysis and trial extension were excluded. Articles that did not mention ONJ in their methods or results were excluded. The primary outcome was the prevalence of a complete definition of ONJ. When no definition was provided, ONJ adjudication process was analyzed.

RESULTS

Of 313 articles found, 13 RCTs were included. A definition of ONJ was detailed in two RCTs (15%). For the remaining 11 RCTs, adjudication process was mentioned for nine. In those processes, "blinded," "expert," and "independent" were the most used words.

CONCLUSION

Most of the published phase III RCTs involving denosumab did not specify the definition of ONJ used to adjudicate events in the study. Instead of definition, non-scientific and non-reproducible expressions were used. Because the chosen definition could impact the ONJ estimated frequency, it should be mandatory to give the precise definition used in each RCT publication involving denosumab.