Learning from experience. Proposal of a refined definition and staging system for bisphosphonate-related osteonecrosis of the jaw (BRONJ)

Italian position paper (SIPMO-SICMF) on medication-related osteonecrosis of the jaw (MRONJ)

OBJECTIVE

This paper aims to describe the 2023 update position paper on MRONJ developed by the Italian Societies of Oral Pathology and Medicine (SIPMO) and of Maxillofacial Surgery (SICMF).

METHODS

This is the second update following the 2013 and 2020 Italian position papers by the Expert panel, which is a representation of the two scientific societies (SIPMO and SICMF). The paper is based on an extensive analysis of the available literature from January 2003 to February 2020, and the subsequent review of literature conducted between March 2020 and December 2022 to include all new relevant published papers to confirm or modify the previous set of recommendations.

RESULTS

This position paper highlights the main issues of MRONJ on risk estimates, disease definition, diagnostic pathway, individual risk assessment, and the fundamental role of imaging in the diagnosis, classification, and management of MRONJ.

CONCLUSION

The Expert Panel confirmed the MRONJ definition, the diagnostic work-up, the clinical-radiological staging system and the prophylactic drug holiday, as recognized by SIPMO-SICMF; while, it presented novel indications regarding the categories at risk of MRONJ, the prevention strategies, and the treatment strategies associated with the therapeutic drug holiday.

How we manage medication-related osteonecrosis of the jaw

Bone-modifying agents (BMAs) are integral to managing patients with advanced cancer. They improve quality of survival by reducing skeletal-related events, treating hypercalcaemia and chemotherapy-induced bone loss (Coleman in Clin Cancer Res 12: 6243s-6249s, 2006), (Coleman in Ann Oncol 31: 1650-1663, 2020). Two decades ago, medication-related osteonecrosis of the jaw (MRONJ) was first reported following BMA therapy (Marx in J Oral Maxillofac Surg 61: 1115-1117, 2003). The risk of MRONJ extends over a decade following BMA treatment with bisphosphonates, complicating dental care such as extractions. In addition, MRONJ has been reported following additional therapies such as antiangiogenic agents, cytotoxic agents, immunotherapy, and targeted agents. The use of BMAs in the curative and adjuvant cancer setting is increasing, consequently the implication of MRONJ is growing. Over the past 20 years, the literature has consolidated major risk factors for MRONJ, the pathophysiology and management strategies for MRONJ. Our review aims to document the development of MRONJ preventative and management strategies in cancer patients receiving a BMA. The authors advocate the incorporation of dental oncology strategies into contemporary cancer care, to optimise long-term quality of survival after cancer treatment.

Navigating the complexities and controversies of medication-related osteonecrosis of the jaw (MRONJ): a critical update and consensus statement

OBJECTIVES

To provide a critical update identifying the knowledge gaps and controversies in medication-related osteonecrosis of the jaw (MRONJ) within the Belgian healthcare context and outline opportunities for improvement and research in these areas.

METHODS

A literature review was performed to identify guidelines from international clinical societies in oncology or oral and maxillofacial surgery on diagnosing, preventing, and treating MRONJ. The recommendations were critically assessed in light of recent developments in the field and confronted with the clinical experience of experts.

RESULTS

Despite progress in the diagnostic criteria of MRONJ, the continued need for an 8-week timeout period should be reconsidered. Furthermore, 3D imaging techniques should be introduced to improve diagnosis and staging. The staging system remains ambiguous regarding Stage 0 MRONJ, and ongoing confusion exists regarding the term non-exposed MRONJ. The prevention of MRONJ should be tailored, considering the individual patient's risk of MRONJ, frailty, and life expectancy. More research seems needed into the efficacy and safety of drug holidays, considering the risks of rebound remodeling on fractures. With renewed interest in surgical and adjunct management techniques, adequately designed clinical studies are needed to help translate trial outcomes into universally applicable treatment guidelines taking into account individual patient characteristics.

CONCLUSIONS

Important knowledge gaps remain and hamper the development of clinical guidelines. Several controversies were identified where consensus is lacking, and further harmonization between stakeholders is necessary. Finally, the need for randomized controlled comparative clinical trials in MRONJ resonates harder than ever to identify the best treatment for individual patients.

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.

Radiologic findings of osteonecrosis, osteoradionecrosis, osteomyelitis and jaw metastatic disease with cone beam CT

PURPOSE

The purpose of this study was to assess CBCT scans of patients with medication related osteonecrosis of the jaws (MRONJ), osteoradionecrosis (ORN), osteomyelitis (OM) and jaw metastatic disease (JM), evaluate the presence and extent of radiologic findings, identify radiologic parameters that may distinguish the four entities and last, introduce a new modified radiographic index (CRIm), in order to contribute to the diagnosis of these conditions.

METHODS

Τwo major databases were retrospectively searched for fully documented and diagnosed CBCT scans of MRONJ, ORN, OM and JM from 2006 to 2019. 335 CBCT scans met the inclusion criteria and were assessed under standardized viewing conditions blindly by 2 observers. The CRIm index proposed in this study evaluates: lytic changes, sclerosis, periosteal bone formation, sequestration, non-healing extraction sockets and other findings which included: sinus implication, inferior alveolar canal implication and jaw fracture. Lytic changes, sclerosis, periosteal bone formation, sequestration and non-healing extraction sockets were scored as: absent (0), localized/single (1) and extensive/multiple (2). Each one of other findings were scored individually as: absent (0) and present (1). For statistical analysis t-test, Pearson's r correlation coefficient, one-way ANOVA and Bonferonni were performed.

RESULTS

Extensive lytic changes were the most common finding, especially for ORN, where it occurred in all CBCT scans (100%). The mean value of the CRIm index differs significantly between CBCT scans with MRONJ and JM, as well as between those with OM and JM (Bonferroni p < 0.001).

CONCLUSIONS

The new modified Composite Radiographic Index introduced in this study, appears to have improved an objective approach to the previously used Composite Radiographic Index by means of cumulative radiologic features. Τhe predominance of certain radiologic features in one or more of these entities may lead the diagnostician towards the correct diagnosis.

Prediction of medication-related osteonecrosis of the jaws using machine learning methods from estrogen receptor 1 polymorphisms and clinical information

Objective

The purpose of this study was to evaluate the effect of estrogen receptor 1 (ESR1) polymorphisms on the development of medication-related osteonecrosis of the jaws (MRONJ) in women with osteoporosis.

Methods

A total of 125 patients taking bisphosphonates was evaluated the relationship between MRONJ occurrence and single nucleotide polymorphisms (SNPs) of ESR1. Clinical information was collected, including current age, treatment duration, and comorbidity. Univariate and Multivariable regression analyzes were performed to evaluate the independent predictive factors for MRONJ occurrence. Predictive models were constructed using machine learning methods such as Lasso regression, Random forest (RF), and Support vector machine (SVM). The area under the receiver-operating curve (AUROC) was used to evaluate the performance of a binary classifier.

Result

Two SNPs of ESR1 (rs4870056 and rs78177662) were significantly associated with MRONJ development. Patients with variant allele (A) of rs4870056 showed 2.45 times (95% CI, 1.03-5.87) the odds of MRONJ occurrence compared to those with wild-type homozygote (GG) after adjusting covariates. Additionally, carriers with variant allele (T) of rs78177662 had higher odds than those with wild-type homozygote (CC) (adjusted odds ratio (aOR), 2.64, 95% CI, 1.00-6.94). Among demographic variables, age ≥ 72 years (aOR, 3.98, 95% CI, 1.60-9.87) and bisphosphonate exposure ≥48 months (aOR, 3.16, 95% CI, 1.26-7.93) were also significant risk factors for MRONJ occurrence. AUROC values of machine learning methods ranged between 0.756-0.806 in the study.

Conclusion

Our study showed that the MRONJ occurrence was associated with ESR1 polymorphisms in osteoporotic women.

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.

MicroRNA in medication related osteonecrosis of the jaw: a review

Medication related osteonecrosis of the jaw (MRONJ) is a condition caused by inhibition of the osteoclast activity by the anti-resorptive and anti-angiogenic drugs. Clinically, there is an exposure of the necrotic bone or a fistula which fails to heal for more than 8 weeks. The adjacent soft tissue is inflamed and pus may be present as a result of the secondary infection. To date, there is no consistent biomarker that could aid in the diagnosis of the disease. The aim of this review was to explore the literature on the microRNAs (miRNAs) related to medication related osteonecrosis of the jaw, and to describe the role of each miRNA as a biomarker for diagnostic purpose and others. Its role in therapeutics was also searched. It was shown that miR-21, miR-23a, and miR-145 were significantly different in a study involving multiple myeloma patients as well as in a human-animal study while miR-23a-3p and miR-23b-3p were 12- to 14-fold upregulated compared to the control group in an animal study. The role of the microRNAs in these studies were for diagnostics, predictor of progress of MRONJ and pathogenesis. Apart from its potential diagnostics role, microRNAs have been shown to be bone resorption regulator through miR-21, miR-23a and miR-145 and this could be utilized therapeutically.

The combined use of photobiomodulation therapy and platelet-rich fibrin for the management of two MRONJ stage II cases: An alternative approach

Medication-related osteonecrosis of the jaws (MRONJ) is a relatively rare but serious adverse drug reaction in patients under bone-targeting or antiangiogenic medication for malignant or osteometabolic diseases. The pathogenesis of MRONJ is multifactorial with the inhibition of osteoclasts and angiogenesis considered to play a keyrole in an individually susceptible environment, thus its prevalence is highly differentiated according to each study. Even though MRONJ has been reported since 2003 and the literature is expanding rapidly about possible risk factors, prevention and treatment options, the successful management with no recurrence is still under controversy. The conservative non-surgical (optimal oral hygiene, systemic antibiotic therapy) and surgical procedures (debridement, sequestrectomy or bone resection) are considered the treatment of choice especially at the early stages. Adjuvant therapies have been proposed to further stimulate bone and tissue healing such as teriparatide, bone morphogenic proteins, platelet concentrates, hyperbaric oxygen, ozone therapy, photodynamic therapy and lasers with promising results. The need to develop minimally invasive treatment protocols using novel technologies in particular for those patients with severe medical history has been highlighted in the literature. The clinical protocol that has been developed in our dental department, which is effectively contributing to MRONJ management and associates Photobiomodulation therapy (PBMT) with platelet-rich fibrin (A-PRF), will be presented in this article.

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.

Radiographic predictors for MRONJ in oncologic patients undergoing tooth extraction

Tooth extraction is a risk factor for the development of osteonecrosis of the jaw following treatment with antiresorptive drugs (ARDs), but not all extraction sites develop this pathology. Therefore, we aimed to identify local radiographic predictors of Medication-Related Osteonecrosis of the Jaw (MRONJ) in panoramic images of oncologic patients undergoing tooth extraction. Based on a retrospective longitudinal cohort study design, patients were included if undergoing one or more tooth extraction, with at least one administration of ARDs, and presence of pre- and post-operative panoramic radiographs. After data collection, blinded and independent observations were performed. Eleven distinct imaging-related parameters were assessed preoperatively and five postoperatively, at each extraction site. A case-control and subgroup analysis assessing MRONJ development was performed. Significance level is set to 0.05 (5%). A total of 77 oncologic patients were selected, undergoing 218 tooth extractions, from which 63 teeth (29%) in 39 patients (51%) developed MRONJ. Results showed that patients developed significantly more MRONJ with longer ARD treatment (p = 0.057), teeth with absent and incomplete endodontic fillings with caries, widened periodontal ligament space and/or periapical lesions (p = 0.005), and sclerotic and heterogenous bone patterns (p = 0.005). In conclusion, tooth extraction sites presenting with infections and bone sclerosis are at higher risk to develop MRONJ.

Effects of Soft Tissue Closure on Medication-Related Osteonecrosis of the Jaw in a Rabbit Model with Tooth Extraction: A Pilot Study

Objectives

The study investigated the effect of soft tissue closure after tooth extraction on the prevention of medication-related osteonecrosis of the jaw in a rabbit model.

Materials and Methods

Twenty female New Zealand white rabbits were randomly assigned into the experimental group administrated with zoledronic acid (ZA) and control groups treated with saline. Bilateral lower premolar extraction was performed 4 weeks after ZA/saline administration. Immediately after extraction, the wound on the right mandible was closed by suture while the other side was left open. Animals were sacrificed 4 weeks and 8 weeks after tooth extraction. Fluorochrome labeling solutions were injected subcutaneously to evaluate the bone growth rates. The mandibles were harvested and subjected for microcomputed tomography, confocal microscope, and histomorphological examinations.

Results

All extraction sites healed well without any signs of infection. Trabecular thickness (Tb.Th) was significantly higher in the ZA-treated group than in the control group at both week 4 and week 8, while no significant difference was detected in the rest of the assessed parameters. The bone growth rate in mandibles showed gradual reduction in the ZA-treated group. Histological analysis showed that at week 8, the animals in the ZA-treated group had significantly higher incidence of osteonecrosis than that in the control group, while no significance was revealed between the sutured and nonsutured side.

Conclusions

ZA treatment significantly reduces bone growth rates but does not reveal a significant effect on bone mineral density and bone microarchitecture. Soft tissue closure of the extraction socket does not reduce the incidence of ONJ in the ZA-treated rabbit model.

CD34 and CD105 Microvessels in Resected Bone Specimen May Implicate Wound Healing in MRONJ

Clinical treatment outcome of MRONJ (medication-related osteonecrosis of the jaw) surgery despite radical osseous removal and primary closure healing still shows differences in terms of outcome and disease recurrence. The study aims to assess the rate of angiogenesis of MRONJ lesions in order to understand the impact of angiogenesis and neoangiogenesis status on MRONJ surgical treatment outcome. This is the first study correlating microvessel density with prognosis in MRONJ surgically-treated patients. The immunohistochemical expression of CD34 and CD105 in MRONJ specimens obtained from surgically-treated patients was evaluated. The most vascularized areas detected by CD34 and CD105 were selected and the microvessel density value of the samples was registered. Samples were retrospectively divided according to the clinical outcome of MRONJ surgical treatment, dividing patients into two groups, “healed” and “not healed”. Statistical analysis was performed to assess if neovessels could influence treatment outcome in patients undergoing radical surgery. In the examined cohort, this value was highly predictive of better treatment outcome after radical surgery of MRONJ. Understanding of angiogenesis-dependent factors deserves further attention as a future target for MRONJ prevention and therapies.

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.

Medication-Related Osteonecrosis of the Jaw: A Critical Narrative Review

Background: Nearly two decades have passed since a paradoxical reaction in the orofacial region to some bone modifying agents and other drugs was recognized, namely medication-related osteonecrosis of the jaw (MRONJ). Purpose: The aim of this manuscript was to critically review published data on MRONJ to provide an update on key terminology, concepts, and current trends in terms of prevention and diagnosis. In addition, our objective was to examine and evaluate the therapeutic options available for MRONJ. Methods: The authors perused the most relevant literature relating to MRONJ through a search in textbooks and published articles included in several databases for the years 2003–2021. Results and conclusions: A comprehensive update of the current understanding of these matters was elaborated, addressing these topics and identifying relevant gaps of knowledge. This review describes our updated view of the previous thematic blocks, highlights our current clinical directions, and emphasizes controversial aspects and barriers that may lead to extending the accumulating body of evidence related to this severe treatment sequela.

A multicenter observational study on Medication-Related Osteonecrosis of the Jaw (MRONJ) in advanced cancer and myeloma patients of a cancer network in North-Western Italy

BACKGROUND

Incidence of Medication-Related Osteonecrosis of the Jaw (MRONJ) related to cancer and myeloma treatments is undetermined, with scarce data varying from 2 to 7.8/million/year in limited investigated populations. A 9-years [2009-2018] regional-wide survey was conducted, deploying the North-Western Italy Cancer Network ("Rete Oncologica Piemonte e Valle d'Aosta"), to assess number and main characteristics of MRONJ cases among myeloma/cancer patients, within a population of 4.5 million inhabitants.

MATERIAL AND METHODS

MRONJ cases were collected retrospectively from January 2009 to June 2015; from July 2015 to December 2018, data were collected prospectively. Number of new MRONJ cases per year, underlying disorder, drug(s) administered, treatment duration, site and onset timing of MRONJ were detailed.

RESULTS

459 MRONJ cases were identified. Primary diseases were breast cancer (46%), prostate cancer (21%), myeloma (19%), and other types of carcinoma (14%). Patients received antiresorptive treatment either alone (399; 88.47%) or in combination with biological agents (52; 11.53%); 8 patients (1.7%) received only antiangiogenic drugs. Zoledronic acid [388] and denosumab [59] were the most frequently administered drugs. Mandible was involved in 296 (64,5%) cases. Number of new MRONJ cases was stable from 2009 to 2015, with a mean of 51.3 cases per year (raw incidence: 11.6/million/year), declining in the 2016-2018 years to 33.3 cases per year (raw incidence: 7.5/million/year).

CONCLUSIONS

With such discrepancy of cases overtime being partially explicable, number of new MRONJ cases per year are consistent with those observed in a previous study [2003-2008] in the same region, being instead higher than those reported in other populations.

A Comparison of the Clinical and Radiological Extent of Denosumab (Xgeva®) Related Osteonecrosis of the Jaw: A Retrospective Study

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive medication. The aim of this study was to evaluate the incidence of denosumab-related osteonecrosis of the jaw and to compare the clinical and radiological extent of osteonecrosis. A retrospective study of patients who received Xgeva^® at the Institut de Cancérologie de Lorraine (ICL) was performed. Patients for whom clinical and radiological (CBCT) data were available were divided into two groups: “exposed” for patients with bone exposure and “fistula” when only a fistula through which the bone could be probed was observed. The difference between clinical and radiological extent was assessed. The p-value was set at 0.05, and a total of 246 patients were included. The cumulative incidence of osteonecrosis was 0.9% at 6 months, 7% at 12 months, and 15% from 24 months. The clinical extent of MRONJ was significantly less than their radiological extent: in the “exposed” group, 17 areas (45%) were less extensive clinically than radiologically (p < 0.001) and respectively 6 (67%) for the “fistula” group (p < 0.031). It would seem that a CBCT is essential to know the real extent of MRONJ. Thus, it would seem interesting to systematically perform a CBCT during the diagnosis of MRONJ, exploring the entire affected dental arch.

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.

A critical assessment of the medication-related osteonecrosis of the jaw classification in stage I patients: a retrospective analysis

Objectives

It is unclear whether the extent of intraoral mucosa defects in patients with medication-related osteonecrosis of the jaw indicates disease severity. Therefore, this study investigated whether mucosal lesions correlate with the true extent of osseous defects in stage I patients.

Materials and Methods

Retrospectively, all patients with stage I medication-related osteonecrosis of the jaw who underwent surgical treatment between April 2018 and April 2019 were enrolled. Preoperatively, the extent of their mucosal lesions was measured in clinical evaluations, and patients were assigned to either the visible or the probeable bone group. Intraoperatively, the extent of necrosis was measured manually and with fluorescence.

Results

Fifty-five patients (36 female, 19 male) with 86 lesions (46 visible bone, 40 probeable bone) were enrolled. Intraoperatively, the necrotic lesions were significantly larger (P<0.001) than the preoperative mucosal lesions in both groups. A significant (P<0.05) but very weak (R2<0.2) relationship was noted between the extent of the mucosal lesions and the necrotic bone area.

Conclusion

Preoperative mucosal defects (visible or probeable) in patients with medication-related osteonecrosis of the jaw do not indicate the extent of bone necrosis or disease severity.

Human amniotic membrane: an improvement in the treatment of Medication-related osteonecrosis of the jaw (MRONJ)? A case-control study

The aim of this article is to report the results obtained by the use of HAM in surgical wound healing and the reduction of relapse in patients affected by Medication-related osteonecrosis of the jaw (MRONJ).The study involved patients with the diagnosis of MRONJ, surgically treated between October 2016 and April 2019, in a case-control setting. Enrolled patients were randomly divided into 2 groups. One group will be treated with resective surgery and with the insertion of HAM patch (Group A), while the second group had been treated exclusively with resective surgery (Group B).The patients underwent MRONJ surgical treatment with the placement of amniotic membrane patches at the wound site. Data regarding the long-term complications/functions were evaluated at 3, 6, 12, and 24 months after surgery. Pain measurements were performed before the intervention (T0), 7(T1) and 30(T2) days after surgery. 49 patients were included in the study. 2 patients of GROUP A after 30 days since they were surgically treated showed persistent bone exposure. 5 patients of group B demonstrated a lack of healing of the surgical wound with the persistence of bone exposed to 30 days after surgery. Statistical analysis ruled out any difference in OUTCOME (relapse) between GROUP A and B (p = 0.23). However, the Fisher test highlighted a significant difference between the use of HAM and only surgical treatment in pain at rest (p = 0.032). The use of amniotic membrane implement the patient's quality of life and reduce pain perception. has a learning curve that is fast enough to justify its routine use.

A New Medical Record Proposal to the Prognostic Risk Assessment for MRONJ in Oncologic Patients: "Sapienza Head and Neck Unit" Proposal

Medication-related osteonecrosis of the jaw (MRONJ) is an adverse event associated with antiresorptive and antiangiogenic drugs. The use of these drugs in the treatment of cancer patients with bone metastasis is necessary and standardized in the literature. A multidisciplinary approach for the patient’s management is strongly recommended. Therefore, it should be necessary to integrate the path of these subjects with a dedicated dental screening in order to first assess the individual risk of developing a MRONJ, and then to plan dental treatments and oral hygiene sessions, and finally to schedule a follow-up to intercept and treat early osteonecrosis. The aim of this manuscript is to propose a new simple medical report to evaluate patients affected by metastatic bone cancer in order to reduce the risk of developing MRONJ.

Assessment of jaw osteonecrosis diagnostic criteria in cancer patients with a history of radiation therapy and exposure to bone-modifying agents

BACKGROUND

Osteoradionecrosis (ORN) of the jaw is currently defined by the development of osteonecrosis in head/neck irradiated patients, regardless of lesion exposure. To diagnose medication-related osteonecrosis of the jaw (MRONJ), a history of any radiation therapy to the jaw region must be ruled out. The aim of this study was to assess the accuracy of current osteonecrosis criteria, while introducing new modifications for improved diagnosis and treatment.

METHODS

One hundred and forty-one necrotic lesions were analyzed from patients exposed to bone-modifying agents (BMAs) and/or received head and neck regional radiation therapy, where the maximal dose of radiation exposure to the jaw osteonecrosis site was calculated. Modified diagnostic criteria were used to reassess all cases and a comparison of outcomes was performed using Pearson's Chi-Square/Fisher's exact test.

RESULTS

Only in patients with primary head and neck carcinomas did the maximal mean radiation dose in the necrotic jaw site reach ranges associated with ORN formation (>40 Gy), with individual cases showing exposures as low as 0-2 Gy. Based on the modified diagnostic criteria almost 2/3 of the necrotic cases diagnosed as ORN should be diagnosed as MRONJ.

CONCLUSIONS

ORN diagnosis should only be considered in cases of radiation exposure >40 Gy to prevent misdiagnosis and suboptimal treatment. A modified criterion for MRONJ diagnosis is recommended where radiation exposure <40 Gy in the necrotic site is included. In cases with exposure >40 Gy and BMA administration, an additional modification to diagnostic criteria of 'medication- and radiation-related osteonecrosis of the jaw', should be used.

Medication-Related Osteonecrosis of the Jaws and CDK4/6 Inhibitors: A Recent Association

The purpose of the present study was to estimate the prevalence of cyclin-dependent kinase (CDK) 4/6 inhibitors use among cancer patients from the medication-related osteonecrosis of the jaw (MRONJ) cohort of the University of Messina. We retrospectively reviewed the records of all patients with either intravenous bisphosphonates or denosumab-related MRONJ reported in the electronic health records of the Unit of Oral Surgery, School of Dentistry, University of Messina between the first quarter of 2018 and the first quarter 2020 to identify eligible patients. We observed six cases of MRONJ associated with CDK4/6 inhibitors concomitantly with intravenous bisphosphonates and/or denosumab in breast cancer patients. The CDK4/6 inhibitors registered were palbociclib (n = 5) and abemaciclib (n = 1). Data of cancer patients diagnosed with MRONJ in the same period (n = 10) were extracted for comparison. The comparative assessment with this group of patients showed a similar distribution of MRONJ stage ranged and clinical course after treatment. The degree of risk for osteonecrosis in patients taking these new classes of drugs is uncertain but warrants awareness and close monitoring. The role of premedication dental evaluation as a prevention strategy has been acknowledged for cancer patients about to initiate intravenous bisphosphonates and/or denosumab for treatment of bone metastasis, but additional attention should be paid to whom are assuming CDK4/6 inhibitors because of their oral adverse events.

Several issues regarding the diagnostic imaging of medication-related osteonecrosis of the jaw

This review presents an overview of some diagnostic imaging-related issues regarding medication-related osteonecrosis of the jaws (MRONJ), including imaging signs that can predict MRONJ in patients taking antiresorptive drugs, the early imaging features of MRONJ, the relationship between the presence or absence of bone exposure and imaging features, and differences in imaging features by stage, between advanced MRONJ and conventional osteomyelitis, between oncologic and osteoporotic patients with MRONJ, and depending on the type of medication, method of administration, and duration of medication. The early diagnosis of MRONJ can be made by the presence of subtle imaging changes such as thickening of the lamina dura or cortical bone, not by the presence of bone exposure. Most of the imaging features are relatively non-specific, and each patient's clinical findings and history should be referenced. Oral and maxillofacial radiologists and dentists should closely monitor plain radiographs of patients taking antiresorptive/antiangiogenic drugs.

Conservative non-surgical management in medication related osteonecrosis of the jaw: A retrospective study

Objectives

To date, the best treatment for Medication Related Osteonecrosis of the jaw (MRONJ) is controversial. Recent studies suggest different therapies, considering the stage of MRONJ; however, sometimes patients, although with remarkable extension of disease, cannot undergo surgery. The purpose of present preliminary study was to evaluate the efficacy of conservative non‐surgical treatment of MRONJ lesions in a cohort of patients ineligible for surgery or refusing any surgical treatment for stage II and III of MRONJ.

Materials and methods

Patients with MRONJ (staging II or III) ineligible for surgical treatment were selected for a retrospective study. A conservative non‐surgical therapy (antibiotics and antiseptic) was administered for 1 year. Five scheduled checks were performed to assess changes in signs and symptoms during the observational period.

Results

Our observation was carried out on 12 patients. Improvement of signs and symptoms of disease were observed in population.

Conclusion

This study suggests that non‐surgical treatment may be a valid therapeutic option in patients ineligible for surgery. The sample size is small, further studies should be carried out to satisfy the aim of a conservative non‐surgical treatment protocol establishment.

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.

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.

Review and update on drugs related to the development of osteonecrosis of the jaw

Background

Medication-related osteonecrosis of the jaw (MRONJ) is a rare, but serious adverse effect of certain drugs, of which bisphosphonates are the most widely known. This pathology is also associated with other medications such as the biologic antiresorptive agent, denosumab and some antiangiogenics such as sunitinib, bevacizumab or aflibercept. Very recently, new medications have also been associated with osteonecrosis of the jaw (ONJ). The objectives were to update the list of medications associated with ONJ, to analyze the fundamental aspects of this list and to describe the level of evidence available.

Material and Methods

A narrative bibliographic review was made, using the PubMed-MedLine, DOAJ and SCIELO databases. Additional information was obtained through the online Medication Information Centre of the Spanish Agency of Medicines and Medical Devices (AEMPS – CIMA), the websites of the US Food & Drugs Administration (Drugs@FDA) and the European Medicines Agency (EMA).

Results

The latest drugs identified as potential facilitators of this pathology include a number of anti-VEGF based antiangiogenic drugs and anti-TKI and different types of immunomodulators. Neither the level of evidence in this association nor the risk are equal for all these drugs. On the other hand, over the coming years, new drugs will be marketed with similar action mechanisms to those that are recognized as having this adverse effect.

Conclusions

No effective therapy is currently known for the treatment of ONJ. Therefore, in order to prevent new cases of MRONJ, it is essential for all oral healthcare professionals to be fully up-to-date with the etiopathogenic aspects of this pathology and to be aware of those drugs considered to be a risk.

Key words:Osteonecrosis of the jaw, MRONJ, bisphosphonates, antiresorptives, antiangiogenics.

Metabolomic profiling reveals salivary hypotaurine as a potential early detection marker for medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious adverse event of bone-modifying agents used to prevent bone complications in cancer patients with bone metastasis. Currently, early treatment is the only way to prevent further progression, as the pathogenesis of MRONJ has not yet been elucidated, and a standard treatment has not been established. The aim of this study was to identify a marker for early detection marker of MRONJ by exploring substances in saliva specific to MRONJ at an early stage. We collected salivary samples from 17 patients with MRONJ and conducted metabolomic analyses using capillary electrophoresis mass spectrometry for non-targeted analysis of hydrophilic metabolites. In the screening cohort, we compared the saliva of patients with stage ≥1 advanced MRONJ (n = 9) with that of controls without MRONJ before chemotherapy (n = 9). The top 5 most elevated salivary metabolites were histamine, 3-(4-hydroxyphenyl)propionate, malonate, carnosine, and hypotaurine. In the validation cohort, we analyzed additional patients with stage ≥1 advanced MRONJ (n = 8) and controls without MRONJ after chemotherapy (n = 9), confirming a significant 2.28-fold elevation in the salivary concentration of hypotaurine. These results revealed elevated salivary hypotaurine concentration as a potential marker for the early detection of MRONJ.

Medication-Related Osteonecrosis of the Jaw: MASCC/ISOO/ASCO Clinical Practice Guideline

PURPOSE

To provide guidance regarding best practices in the prevention and management of medication-related osteonecrosis of the jaw (MRONJ) in patients with cancer.

METHODS

Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) and ASCO convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations. Guideline development involved a systematic review of the literature and a formal consensus process. PubMed and EMBASE were searched for studies of the prevention and management of MRONJ related to bone-modifying agents (BMAs) for oncologic indications published between January 2009 and December 2017. Results from an earlier systematic review (2003 to 2008) were also included.

RESULTS

The systematic review identified 132 publications, only 10 of which were randomized controlled trials. Recommendations underwent two rounds of consensus voting.

RECOMMENDATIONS

Currently, MRONJ is defined by (1) current or previous treatment with a BMA or angiogenic inhibitor, (2) exposed bone or bone that can be probed through an intraoral or extraoral fistula in the maxillofacial region and that has persisted for longer than 8 weeks, and (3) no history of radiation therapy to the jaws or metastatic disease to the jaws. In patients who initiate a BMA, preventive care includes comprehensive dental assessments, discussion of modifiable risk factors, and avoidance of elective dentoalveolar surgery (ie, surgery that involves the teeth or contiguous alveolar bone) during BMA treatment. It remains uncertain whether BMAs should be discontinued before dentoalveolar surgery. Staging of MRONJ should be performed by a clinician with experience in the management of MRONJ. Conservative measures comprise the initial approach to MRONJ treatment. Ongoing collaboration among the dentist, dental specialist, and oncologist is essential to optimal patient care.

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.

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.

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.

Osteonecrosis of the jaw (ONJ) in patients who receive Bone Targeting Agents (BTAs): the power of e-learning

The definition, pathobiology and risk factors of ONJ in cancer patients who receive BTAs are discussed in the recent ecancer module for osteonecrosis of the jaw (http://ecancer.org/education/module/276-osteonecrosis-of-the-jaw.php). ONJ prevention, early diagnosis and management are presented. The critical question of the performance of dental extraction, during BTA therapy, as indicated with the recent studies, is supported. The importance of the collaboration between dental and oncology professionals and the patients is highlighted and can be achieved through appropriate education. The ecancer modules are valuable tools for successful e-learning in medical oncology education, including ONJ.

Detecting the earliest radiological signs of bisphosphonate-related osteonecrosis

Introduction Oral bisphosphonates are the most commonly prescribed anti-resorptive drugs used in the treatment of osteoporosis, but osteonecrosis of the jaw is a serious complication. The early diagnosis of this destructive side effect is crucial in preventing excessive bone loss, pain and infection.Objective To aid dental practitioners in the early identification of bisphosphonate-related osteonecrosis of the jaw.Method A scoping review was carried out.Data sources We searched MEDLINE via OVID, EMBASE via OVID, Dentistry and Oral Sciences Source (DOSS), Proquest Dissertation and Theses Search, to identify references that described clinical and radiological findings in medication-related osteonecrosis of the jaw (MRONJ).Data selection Nineteen references mentioned the earliest radiological changes in MRONJ with a description of the observations and were included in the analysis.Data synthesis The radiographic signs included osteosclerosis/lysis, widening of the periodontal ligament and thickening of the lamina dura and cortex. To assess the quality of original data on which recommendations had been made, these 19 studies were subjected to a quality appraisal.Conclusion Using bone exposure as a criterion for diagnosis of MRONJ, leads to delayed diagnosis and a poor response to treatment. In those patients at risk of bone exposure with MRONJ, insufficient information is present in the literature to allow the general dental practitioner to reliably identify the radiographic features indicating imminent bone exposure. A well-designed prospective study is needed.

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.

Imaging of Radiation- and Medication-Related Osteonecrosis

Osteonecrosis is the devitalization of bone and consequent lytic changes. In the jaws, osteonecrosis is a pathologic consequence of prior radiation therapy (osteoradionecrosis) or certain antiresorptive medications. Herein, we review the pathogenesis and clinical manifestations of these lesions, and describe the spectrum of radiologic findings in these conditions, and highlight the similarities and differences between the imaging appearances of these 2 entities.

Osteonecrosis of the Jaw (ONJ) in Osteoporosis Patients: Report of Delayed Diagnosis of a Multisite Case and Commentary about Risks Coming from a Restricted ONJ Definition

Osteonecrosis of the jaws (ONJ) in osteoporosis patients has been defined as rare, but the number of reported cases is increasing. We report a case of delayed ONJ diagnosis in a patient, who was being treated with alendronate, developing bone alterations both in maxilla and in mandible. Underestimation of ONJ incidence and missed or delayed ONJ diagnosis in osteoporosis patients might derive from lack of awareness of health providers as well as from an ONJ definition that is too restricted. The more recent definition of medication-related osteonecrosis of the jaws (MRONJ) released in 2014 by the American Association of Oral Maxillofacial Surgeons (AAOMS) accept fistula, besides bone exposure, as a major sign of disease, but it seems to be insufficient since it excludes all cases of ONJ disease without bone exposure. A new MRONJ definition is needed to avoid missing or delayed diagnosis.

Uncertainty of current algorithm for bisphosphonate-related osteonecrosis of the jaw in population-based studies: a systematic review

To assess the relevance of previous epidemiologic studies on bisphosphonate-related osteonecrosis of the jaw (BRONJ), we first conducted a systematic review of large population-based observational studies and evaluated the validity of claims-based algorithms for the identification of BRONJ. Studies containing primary observational epidemiologic data regarding bisphosphonate (BP) exposure and outcomes of osteonecrosis of the jaw were systematically reviewed. Using surrogates for identifying potential BRONJ cases from a population-based hospital registry, validation was performed through medical chart review. Positive predictive value (PPV) was estimated for each diagnostic code and for the overall algorithm utilized. Various strategies to increase PPV were also performed. Seventeen studies were systematically reviewed and presented with variations in study quality as well as inconsistent findings. Moreover, there was a high level of methodological heterogeneity. A total of 1920 patients were identified through the ICD-10 algorithm with potential BRONJ, although only 109 cases were confirmed, corresponding to an overall PPV of 5.68% (95% confidence interval [CI] 4.68-6.81). Only K10.2 (inflammatory conditions of the jaw) exhibited a relatively high PPV of 26.18%, which increased to 74.47% after confinement to BP users. Other strategies to increase PPV value were not effective. Our findings showed that the overall PPV for BRONJ identification was very low, indicating low validity of the current algorithm and possible overestimation of ONJ occurrence. There is an urgent need to develop more reliable and specific operational definitions for the identification of BRONJ cases in large population databases. © 2016 American Society for Bone and Mineral Research.

Interrelationship of clinical, radiographic and haematological features in patients under bisphosphonate therapy

OBJECTIVES

To analyze the clinical, radiographic and haematological aspects of patients under bisphosphonate therapy.

METHODS

A retrospective study was conducted where the records of patients taking bisphosphonates were analyzed considering the occurrence of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Evaluation included panoramic and periapical radiographies, haematological examinations and clinical features. Radiographies were analyzed determining the presence or absence of bone sclerosis, osteolysis, persisting alveolar socket, narrowing of the mandibular canal, widening of the periodontal ligament space, periradicular radiolucency, sequestrum and thickening of the lamina dura. Laboratory tests consisted of complete blood count, fasting serum glucose, erythrocyte sedimentation rate (ESR) and serum levels of calcium, phosphorus, alkaline phosphatase, parathormone (PTH) and C-terminal telopeptide of collagen I (CTX).

RESULTS

Alkaline phosphatase and ESR were significantly higher in the BRONJ group, whereas fasting serum glucose, CTX, PTH, calcium and phosphorus did not significantly differ. BRONJ showed association with smoking, tooth extraction, anaemia and leukocytosis. On radiographic analysis, persisting alveolar socket, osteolysis, bone sclerosis and narrowing of the mandibular canal were significantly more prevalent in the BRONJ group. Thickening of the lamina dura, periapical radiolucencies, widening of the periodontal ligament space and sequestrum did not significantly differ between the groups.

CONCLUSIONS

BRONJ is a multifactorial disease with high morbidity, which requires experimental studies to clarify the role of the reported risk factors and clinical radiographic signs to improve its diagnosis.

Meaning and Limitation of Cortical Bone Width Measurement with DentaScan in Medication-Related Osteonecrosis of the Jaws

Mandibular cortical bone measurement with x-ray imaging is known to be a potentially useful tool in the detection of dimensional changes caused by bisphosphonate. The primary purpose of this study was to assess the meaning and limitation of cortical bone measurement with computed tomography (CT) in patients with medication-related osteonecrosis of the jaw (MRONJ). The investigators obtained DentaScan images of the mandible from 15 patients with MRONJ, 15 patients with a history of antiresorptive agent administration without symptoms of MRONJ (non-MRONJ), and 15 control subjects. The cortical bone width measured on DentaScan images was compared between the three groups (ANOVA and Tukey's test). Interobserver reliability between two observers was also assessed. The values of interclass correlation coefficient were 0.48 in the MRONJ group, 0.29 in the Non-MRONJ group, and 0.34 in control group. The cortical bone widths calculated both by observer 1 and observer 2 were thicker in patients with MRONJ than in the non-MRONJ group and controls. There were significant differences in cortical bone width among the MRONJ, non-MRONJ, and control groups in observer 1 (P < 0.001) and observer 2 (P < 0.001), specifically comparing the MRONJ group with the non-MRONJ group and the control group. Cortical bone width measurement is useful for the distinction between medication-related osteonecrosis of the jaw and normal bone, in spite of the low interobserver reliability.

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.