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

Prevalence of MRONJ in patients treated with antiresorptive agents for glucocorticoid-induced osteoporosis

PURPOSE

In this study, we aimed to investigate the incidence of medication-related osteonecrosis of the jaw (MRONJ) in patients with glucocorticoid-induced osteoporosis (GIOP) and to examine risk factors for MRONJ development, as well as the preventive effect of tooth extraction before antiresorptive agent (ARA) administration.

METHODS

This retrospective study included patients who received ARA to prevent fragility fractures due to GIOP. The cumulative incidence of MRONJ in patients with GIOP was calculated using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses were used to analyze risk factors for MRONJ occurrence.

RESULTS

The study included 327 individuals. Six patients developed MRONJ; the crude incidence of MRONJ was 1.8%, and the cumulative incidence at 1, 2, 3, 4, and 5 years was 0.32%, 0.97%, 1.35%, 1.85%, and 2.56%, respectively. In this study, 159 teeth were extracted during dental intervention before ARA administration in 58 patients; however, no MRONJ development was observed at the extraction site. Tooth extraction, diabetes mellitus, and duration of ARA administration were not identified as risk factors in this study.

CONCLUSIONS

The incidence of MRONJ in patients with GIOP was higher than the previously reported incidence in patients with age-related osteoporosis but lower than the incidence in patients using high-dose ARA. The results support the effectiveness of prophylactic procedures to remove the infected lesions as much as possible from the jawbone and periodontal tissue before ARA administration.

CLINICAL TRIAL NUMBER

Not applicable.

Molecular targeted drugs affect the development of antiresorptive-related osteonecrosis of the jaw in patients with lung and kidney cancers

The use of antiresorptive agents in patients with cancer is strongly associated with the development of medication-related osteonecrosis of the jaw, with an incidence of ≥10%. Despite the presence of clinical position papers on this issue, the incidence of medication-related osteonecrosis of the jaw has not decreased. Therefore, we believe there are some unknown underlying factors, so we focused on the use of anticancer agents, especially molecular targeted drugs, in this study. We retrospectively evaluated the data of 366 patients who received antiresorptive agents for metastatic cancer treatment. All patients received proper oral care before antiresorptive agent initiation. Of the 366 patients, 48 (13.1%) developed medication-related osteonecrosis of the jaw. Medication-related osteonecrosis of the jaw developed in 18/55 (32.7%) patients who received molecular targeted drugs and in 30/311 (9.6%) patients who did not (p < 0.001). Among patients with lung cancer, 10/29 (34.5%) patients who received molecular targeted drugs and 5/96 (5.2%) who did not (p < 0.001) developed medication-related osteonecrosis of the jaw. In patients with kidney cancer, medication-related osteonecrosis of the jaw developed in 5/11 patients (45.5%) who received molecular targeted drugs and not in any of the 13 patients who did not (p < 0.01). Molecular targeted drugs significantly affect the development of medication-related osteonecrosis of the jaw. Therefore, in cancer treatment, close attention should be paid to antiresorptive agent use and to the details of anticancer therapies for managing medication-related osteonecrosis of the jaw.

Development of a Medication-Related Osteonecrosis of the Jaw Prediction Model Using the FDA Adverse Event Reporting System Database and Machine Learning

Background: Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious adverse event. Herein, we conducted a quantitative structure-activity relationship analysis using the U.S. Food and Drug Administration Adverse Drug Reaction Database System (FAERS) and machine learning to construct a drug prediction model for MRONJ induction based solely on chemical structure information. Methods: A total of 4815 drugs from FAERS were evaluated, including 70 and 139 MRONJ-positive and MRONJ-negative drugs, respectively, identified based on reporting odds ratios, Fisher's exact tests, and ≥100 total adverse event reports. Then, we calculated 326 chemical structure descriptors for each drug and compared three supervised learning algorithms (random forest, gradient boosting, and artificial neural networks). We also compared the number of chemical structure descriptors (5, 6, 7, 8, 9, 10, 20, and 30 descriptors). Results: We indicated that the MRONJ prediction model using an artificial neural network algorithm and eight descriptors achieved the highest validation receiver operating characteristic curve value of 0.778. Notably, the total polar surface area (ASA_P) was among the top-ranking descriptors, and MRONJ-positive drugs such as bisphosphonates and anticancer drugs showed high values. Our final model demonstrated a balanced accuracy of 0.693 and a specificity of 0.852. Conclusions: In this study, our MRONJ-inducing drug prediction model identified drugs with polar surface area properties as potential causes of MRONJ. This study demonstrates a promising approach for predicting MRONJ risk, which could enhance drug safety assessment and streamline drug screening in clinical and preclinical settings.

Prevention of bisphosphonate-related osteonecrosis of the jaw with basic fibroblast growth factor: an experimental study in rats

Bisphosphonate-related osteonecrosis of the jaw (BRONJ), characterized by persistent jaw bone exposure, is believed to result from the inhibition of bone remodeling and wound healing, often associated with potent intravenous bisphosphonates such as zoledronic acid (ZA). These bisphosphonates are known to significantly impact the healing of soft and bone tissues due to their anti-angiogenic properties. Our study aimed to explore whether applying the basic fibroblast growth factor (bFGF), known for its ability to promote angiogenesis and bone remodeling, over extraction sockets could prevent the onset of BRONJ in rats administered with ZA. The experimental protocol involved administering each rat with two intravenous injections of 60 μg/kg of ZA, followed by tooth extraction. Rats were then divided into two groups: the test group (n = 12), which had a mixture of 3% hydroxypropyl cellulose (HPC) and 0.3% bFGF applied over their extraction sockets, and the control group (n = 12), which received only a 3% HPC application. Wound healing was monitored for 8 weeks post-extraction and assessed using micro-computed tomography, histological evaluations, and immunohistochemical analysis of CD31- and CD105-positive vessels. Results showed a BRONJ incidence rate of 100% (12/12) in the control group, whereas the rate was significantly lower in the test group at 8.3% (1/12). Furthermore, the test group demonstrated marked increases in both angiogenesis and new bone formation. Our findings suggest that the local application of bFGF might serve as an effective therapeutic approach to prevent the onset of BRONJ following tooth extraction in patients receiving bisphosphonate therapy.

Medication related osteonecrosis (MRONJ) in the management of CTIBL in breast and prostate cancer patients. Joint report by SIPMO AND SIOMMMS

Background

Low-doses of bone modifying agents (LD-BMAs) compared to those used to treat bone metastases are used in breast or prostate cancer patients on adjuvant endocrine therapy to prevent Cancer Treatment Induced Bone Loss (CTIBL). Their use is associated with an increased risk of developing Medication-Related Osteonecrosis of the Jaw (MRONJ). However, there is not clarity about strategies aimed to minimize the MRONJ risk in cancer patients at different conditions as low- vs high-doses of BMA. This joint report from the Italian Societies of Oral Pathology and Medicine (SIPMO) and of Italian Society of Osteoporosis, Mineral Metabolism and Skeletal Diseases (SIOMMMS) aims to define the dental management of breast and prostate cancer patients with CTIBL under LD-BMAs, to reduce their risk to develop MRONJ.

Methods

This interdisciplinary SIPMO-SIOMMMS Expert Italian Panel reviewed the available international scientific literature and developed a set of recommendations to implement strategies of MRONJ prevention in breast (BC) and prostate cancer (PC) patients undertaking LD-BMAs to prevent CTIBL.

Results

The Expert Panel, after addressing some introductive topics (i.e., CTIBL and its management, pharmacology and pharmacodynamics of BMAs, definition and diagnosis of MRONJ), developed a joint report on the following five issues: a) prevention and dental management in cancer patients candidates to LD-BMAs, or under LD-BMAs; b) prophylactic drug holiday; c) MRONJ treatment; d) LD-BMAs therapeutic drug holiday; and e) restart of LD-BMA treatment after successful healing of MRONJ.Finally, ten key questions with answers were prepared and placed at the end of the document.

Conclusions

Despite obvious weaknesses of the available international literature, the Expert Panel recognized the need to tailor separate MRONJ preventive approach for breast and prostate cancer patients on adjuvant endocrine therapy who begin low-dose BMA therapy to prevent CTIBL and provided this practical guidance for bone specialists and oral healthcare providers. In view of a MRONJ risk for BC and PC patients receiving low-dose BMAs, which approximates that of patients with osteoporosis and other non-malignant diseases undergoing similar treatment schedules, the SIPMO-SIOMMMS Expert Panel recognizes the need for less stringent preventive strategies than those already developed for BC or PC patients with bone metastases taking HD-BMAs.

Medication-Related Osteonecrosis Successfully Treated With Hyperbaric Oxygen Therapy and Conservative Treatment: A Case Report

Medication-related osteonecrosis of the jaws (MRONJ) is a major side effect of the antiresorptive drugs used in treating patients with osteoporosis and cancer. MRONJ appears as prolonged inflammation affecting the maxilla or mandible, with necrotic bone exposure and intraoral and extraoral fistulas. According to previous studies, surgery for this condition is highly beneficial. However, extensive surgical treatment generally overburdens patients with MRONJ, who often already suffer from other diseases such as cancer; therefore, further consideration must be given to their overall condition. Herein, we present the case of an elderly patient with extensive MRONJ who was successfully treated with hyperbaric oxygen therapy and conservative treatment.

Risk factors of medication-related osteonecrosis of the jaw: A clinical investigation

Medication-related osteonecrosis of the jaw (MRONJ) is an intractable condition caused by drugs such as bisphosphonates and denosumab. This study investigated the changes in the incidence of MRONJ in the previous 10 years and examined the poor prognostic factors during surgery in at-risk patients. We compared 57 and 64 patients diagnosed with MRONJ at our hospital between January 2012 and December 2016 and January 2017 and December 2021, respectively. The disease stage and triggers at the time of initial diagnosis in eligible patients were investigated. Additionally, the adverse prognostic factors were examined in 166 patients at risk of MRONJ who underwent tooth extraction at our department during these 10 years. The results indicated that there was no change in the proportion of patients with osteoporosis and malignancy among those with MRONJ. The number of cases after tooth extraction decreased, and those after dental infections increased on comparing the recent 5 years and the preceding 5 years. The number of MRONJ patients receiving denosumab also increased. Denosumab was a significant post-extraction prognostic factor for delayed healing in the 166 patients at risk of MRONJ. The findings suggest that patients receiving denosumab should be closely monitored when undergoing surgery to prevent MRONJ.

Chinese expert consensus on the diagnosis and clinical management of medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a side effect that occurs after treatment for systemic diseases. However, most institutions currently rely on empirical methods to make diagnosis and treatment plans, and there is a lack of consensus or guidelines for the classification, staging and treatment of MRONJ in China. To address this gap and improve prognosis, an expert panel representing 11 renowned domestic medical colleges and affiliated hospitals in China was convened. The panel made a comprehensive literature review of previous treatment experiences and research findings to address issues of definitions, etiology and risk factors, diagnosis, treatment and prevention methods. The panel concluded that the diagnosis of MRONJ can be made on the basis of a history of related medications and typical clinical manifestations, with either typical radiographic manifestations or histopathological manifestations, after excluding jaw metastasis. Surgical treatment should be considered for symptomatic patients with sequestrum or bone abnormalities accompanied by recurrent infections, and He's classification was considered a practical clinical MRONJ staging system. Multidisciplinary comprehensive treatment should be proposed to achieve optimal treatment outcomes.

What Affects Healing Rates in Patients Treated for Medication-Related Osteonecrosis of the Jaw? The Role of Operative Therapy and Other Clinical Factors

BACKGROUND

In the therapy of medication-related osteonecrosis of the jaw (MRONJ), the healing rate, effectiveness of operative therapy, and factors associated with healing remain unclear.

PURPOSE

This study aimed to estimate MRONJ therapy healing rates and identify associated prognostic factors.

STUDY DESIGN, SETTING, SAMPLE

A 25-center prospective cohort study was conducted on 291 patients with MRONJ treated with a common therapeutic protocol during 2013-2016. Patients unable to continue examinations or treatment were excluded.

PREDICTOR VARIABLE

The primary predictor variable was MRONJ therapy grouped into two categories: operative and nonoperative. Secondarily, the prognostic factors categorized as demographic, medical, clinical, and perioperative were evaluated.

MAIN OUTCOME VARIABLES

The primary outcome variable was treatment duration, defined as the time (in months) between the initiation of therapy and when the site was healed or the date of the final visit or loss to follow-up.

COVARIATES

Not applicable.

ANALYSES

Descriptive statistics and 3-year cumulative healing rates were calculated. The association between clinical factors and time to healing was analyzed using bivariate and multivariate analyses and propensity score analysis. P < .05 was considered significant.

RESULTS

We analyzed data from 291 subjects with 76 (26.1%) and 215 (73.9%) subjects in the operative and nonoperative therapy groups, respectively. The healing rates for operative and nonoperative therapies were 95.8 and 70.7%, respectively (hazard ratio [HR] = 1.6, 95% confidence interval [CI] = 1.1-2.2, P value [P] < .01). The healing rates in patients for whom anti-resorptive agent (ARA) treatment was discontinued and continued were 87.2 and 37.4%, respectively (HR = 1.8, 95% CI = 1.1-3.0, P = .02). In a multiple regression analysis using ARA indication, the therapy method showed a significant association in the MRONJ malignancy group (HR = 2.75, 95% CI = 1.46-5.17, P < .01).

CONCLUSION AND RELEVANCE

Operative therapy and ARA discontinuation were associated with better healing rates in MRONJ therapy. However, the choice of therapy for MRONJ should be based on a comprehensive consideration of the patient's condition. ARA discontinuation should be considered an adjunctive measure because of the possibility of adverse events such as fragility fractures and skeletal related events.

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

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

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.

A retrospective case series on bisphosphonate related osteonecrosis of the jaw in 20 cats

Introduction

This retrospective study highlights the salient aspects of a series of feline patients affected with bisphosphonate related osteonecrosis of the jaw. Though more commonly published in human literature, this presentation is rare in cats. The authors hope that this study will assist in making this a more globally known entity with subsequent improved prognosis.

Methods

Data was retrospectively obtained from the medical records between 2015 and 2021 of 20 cats with Medication Related Osteonecrosis of the Jaw. Data included patient information, clinical history, presenting complaint, systemic diseases, details referable to hypercalcemia and treatment thereof, bisphosphonate specifics (dose and duration), clinical presentation of the lesion, diagnostic testing including radiographic and histopathologic descriptions, treatment, and outcome.

Results

Pertinent results include that all 20 cats who developed Medication Related Osteonecrosis of the Jaw had been treated for idiopathic hypercalcemia with the bisphosphonate medication alendronate. Eighty-five percent of the cases had prior dental extractions at the site of MRONJ lesion. Ninety-five percent of the affected cats required a surgical procedure to control the disease. Thirty-five percent of cases required at least one revision surgery after the initial procedure was performed. Diagnosis of MRONJ was made by a correlation of diagnostic findings and patient history. No single diagnostic, or combination was pathognomonic for lesion diagnosis. As well, there were no statistically significant associations between patient variables assessed and the overall patient outcome.

Discussion

The case series reveals that cats with feline idiopathic hypercalcemia treated with alendronate may be at a risk for development of MRONJ, a serious oral condition with significant morbidity. Prior dental extraction sites in patients concurrently treated with bisphosphonate medications were often associated with MRONJ lesions. Therefore, any needed dental surgery should be performed prior to the use of bisphosphonates where possible. The authors have also included a relevant comparative literature review.

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.

Bone resection methods in medication-related osteonecrosis of the jaw in the mandible: An investigation of 206 patients undergoing surgical treatment

Background /purpose

The standard treatment for medication-related osteonecrosis of the jaw (MRONJ) is surgery. However, reports on the appropriate extent of bone resection are few. We aimed to examine the relationship between the extent of bone resection and postoperative outcomes in patients with mandibular MRONJ.

Materials and methods

The clinical and imaging findings and treatment outcomes of 206 patients (258 surgeries) with mandibular MRONJ undergoing surgery were reviewed. Imaging findings were evaluated using computed tomography (CT) to sequestrum, osteolysis, periosteal reaction, and mixed-type osteosclerosis, and determine the extent of resection. In some cases, samples were taken from within the bone, and real-time polymerase chain reaction was used to confirm the presence of bacteria and fungi.

Results

The three-year cumulative cure rate was 81.7%. Patients with malignant tumors showing no osteolysis and undergoing sequestrum removal or marginal mandibulectomy had significantly worse prognosis than those with osteoporosis showing osteolysis and undergoing segmental mandibulectomy. Furthermore, patients with residual osteolysis, periosteal reactions, and mixed-type osteosclerosis on CT were more likely to develop recurrence. Eleven patients showed no osteolysis on CT images. Patients with cancer administered with high-dose denosumab had significantly poorer prognosis. Bacteria and fungi were also detected in samples obtained from gap-type periosteal reaction and mixed-type osteosclerosis.

Conclusion

Surgery for MRONJ requires resection of the infected bone. Aside from the osteolysis area, the gap-/irregular-type periosteal reaction and mixed-type osteosclerosis must also be included in the resection area. Methods for determining the extent of bone resection in MRONJ without osteolysis are a future challenge.

Risk factors for the development of medication-related osteonecrosis of the jaw and effects of tooth extraction with local infection

Background/purpose

Tooth extraction has been avoided in patients receiving antiresorptive agent (ARA) therapy. This study aimed to investigate dental findings associated with medication-related osteonecrosis of the jaw (MRONJ) development in patients.

Materials and methods

First, in patients treated with high-dose ARAs, the relationship between dental findings and MRONJ development was examined. Next, in patients with MRONJ undergoing surgery, the relationship between dental findings and MRONJ occurring at a site distant from the initial site was examined.

Results

MRONJ occurred in 13 of 172 patients (80 of 3725 teeth) during observation. Multiple tooth loss, periodontal ligament space enlargement, alveolar bone loss, periapical osteosclerosis, and local infection symptoms were associated with MRONJ development. Tooth extraction significantly reduced MRONJ development. Regarding other-site recurrence, new MRONJ developed at other sites in 54 of 357 patients with MRONJ (171 of 5038 teeth). Multiple tooth loss, apical lesions, periodontal ligament space enlargement, and periapical osteosclerosis were significantly associated with MRONJ development. In patients with malignant tumors, tooth extraction significantly reduced the subsequent incidence of MRONJ, while in patients with osteoporosis, there was no difference in the incidence of MRONJ between patients with and without tooth extraction.

Conclusion

MRONJ was more likely to develop from teeth with local infections. Extraction of teeth with local infection in patients with malignancy may be more effective than tooth preservation in preventing MRONJ.

Cumulative incidence and risk factors for medication-related osteonecrosis of the jaw during long-term prostate cancer management

Bone-modifying agents (BMA) are extensively used in treating patients with prostate cancer with bone metastases. However, this increases the risk of medication-related osteonecrosis of the jaw (MRONJ). The safety of long-term BMA administration in clinical practice remains unclear. We aimed to determine the cumulative incidence and risk factors of MRONJ. One hundred and seventy-nine patients with prostate cancer with bone metastases treated with BMA at our institution since 2008 were included in this study. Twenty-seven patients (15%) had MRONJ during the follow-up period (median, 19 months; interquartile range, 9-43 months). The 2-year, 5-year, and 10-year cumulative MRONJ incidence rates were 18%, 27%, and 61%, respectively. Multivariate analysis identified denosumab use as a risk factor for MRONJ, compared with zoledronic acid use (HR 4.64, 95% CI 1.93-11.1). Additionally, BMA use at longer than one-month intervals was associated with a lower risk of MRONJ (HR 0.08, 95% CI 0.01-0.64). Furthermore, six or more bone metastases (HR 3.65, 95% CI 1.13-11.7) and diabetes mellitus (HR 5.07, 95% CI 1.68-15.2) were risk factors for stage 2 or more severe MRONJ. MRONJ should be considered during long-term BMA administration in prostate cancer patients with bone metastases.

Survey of the association between tooth extraction and development of medication-related osteonecrosis of the jaw in patients undergoing cancer treatment with bone-modifying agents

OBJECTIVE

This study aimed to verify whether tooth extraction before the administration of bone-modifying agents (BMA) was effective in preventing the onset of medication-related osteonecrosis of the jaw (MRONJ).

MATERIALS AND METHODS

This retrospective study included patients with a history of receiving BMA for cancer treatment. The patients were classified into three groups based on the timing of tooth extraction: no tooth extraction before the onset of MRONJ, tooth extraction before the administration of BMA, and tooth extraction after the administration of BMA. The incidence of MRONJ was compared between the groups. Fisher's exact test and Bonferroni correction were used to test for differences in proportions between the three groups.

RESULTS

The total number of subjects was 123. Twenty-four patients (19.5%) developed MRONJ. The incidence rates were 12.3% (10/81), 17.9% (5/28), and 64.3% (9/14) in the non-extraction group, the extraction before BMA administration group, and the extraction after BMA administration group, respectively, showing statistically significant differences between the extraction after BMA administration group and the non-extraction groups and between the extraction after BMA administration group and the extraction before BMA administration group (p < 0.001, p = 0.0049). On the other hand, there was no statistically significant difference in incidence between the non-extraction and the extraction before BMA administration group (p = 0.5274).

CONCLUSIONS

Tooth extraction before the administration of BMA is effective in preventing the onset of MRONJ in patients receiving BMA for cancer treatment. Prevention of MRONJ development in patients receiving BMA for cancer treatment contributes to the maintenance of patients' quality of life.

Differences Between Medication-Related Osteonecrosis of the Jaw Caused by Bisphosphonates and Denosumab: Histological, Molecular Biological, and Clinical Studies

Purpose Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect of antiresorptive agents such as bisphosphonates (BPs) and denosumab (DMB). We investigated whether a difference exists between BP- and DMB-related osteonecrosis of the jaw (ONJ). Patients and methods Histological images of 30 patients with BP-related ONJ and 13 patients with DMB-related ONJ were observed using hematoxylin-eosin and cathepsin K staining. Moreover, bone metabolism markers in the blood and bone mineral density were measured in 18 patients with BP-related ONJ and five patients with DMB-related ONJ. Furthermore, we conducted a quantitative analysis of local bone metabolism-related genes using surgical specimens through real-time reverse transcription polymerase chain reaction. Additionally, a retrospective study of 298 patients with MRONJ examined the differences in the characteristics of BP- and DMB-related ONJ and the factors associated with treatment outcomes. Results Histological examination revealed that patients treated with DMB had more severe osteoclast suppression than those treated with BP. No significant difference was observed in blood-bone metabolism markers between the two drugs; however, the suppression of local bone metabolism-related genes was stronger in patients treated with DMB. Clinical studies indicate that DMB-related ONJ is more frequently observed without osteolysis. Conclusion BP-associated ONJ and DMB-associated ONJ were shown to differ slightly. Clinical studies indicate that osteolysis is often unclear in DMB-related ONJ, and methods of bone resection during surgery need to be established.

Radiographical Diagnostic Evaluation of Mandibular Cortical Index Classification and Mandibular Cortical Width in Female Patients Prescribed Antiosteoporosis Medication: A Retrospective Cohort Study

Osteoporosis is often detected late and becomes severe because of a lack of subjective symptoms. Digital panoramic radiography (DPR) has been reported to be useful for osteoporosis screening based on the morphological classification of the mandibular inferior cortex. The purpose of this study was to evaluate the sensitivity and specificity of the mandibular cortical index (MCI) in the diagnosis of osteoporosis in a group of patients who were and were not using antiosteoporosis medication (AOM). Three hundred and fifty female patients aged 40 years or older who had DPR imaging performed during a 6-year period from December 2015 to February 2022 met the selection criteria. Two examiners recorded mandibular cortical width and MCI from the images. These results were statistically examined together with the patients' demographic data. Forty-nine patients were using AOM (13 nonbisphosphonate/denosumab and 36 bisphosphonate/denosumab). MCI type 3 was the most common in the AOM group. In the MCI classification, DPR imaging among the AOM group was more sensitive (0.95) than that of the control group. This method of estimating osteoporosis based on MCI classification using DPR images has high sensitivity, especially in patients using AOM, suggesting that this method is useful as a screening test.

Osteonecrosis of the Jaw Associated with Bisphosphonates Infusion for Treatment of Plasma Cell Myeloma-A Retrospective Observational Study of Northern Portuguese Population

Objectives: To verify medication-related osteonecrosis of the jaw (MRONJ) frequency among patients with plasma cell myeloma (PCM) that had been treated with bisphosphonates, to identify predisposing factors that could influence the development of osteonecrosis. Methods: This observational retrospective study was performed at the Department of Hematology of Hospital Center of Porto (CHUP), Portugal. Results: The study population (n = 112) had a 15.2% (n = 17) prevalence of osteonecrosis. Clinically, bone exposure was the most frequently observed sign, present in 100% (n = 17) of the patients, followed by inflammation in 82.4% (n = 14), orofacial pain in 70.6% (n = 12), suppuration in 47.1% (n = 8), and intra or extra-oral fistula in 17.6% (n = 3) of the cases. The most frequent triggering local factor was dental extraction (82.4%). There was a dependence between the presence of extractions and the development of MRONJ (p < 0.001) but not with the time elapsed from the initiation of infusions with BPs and dental extractions (p = 0.499). In the sample of patients with multiple myeloma (MM), 13.8% were found to be more likely to develop MRONJ after an extraction. Conclusions: The most common local predisposing factor was dental extraction. No dependence was observed between the development of osteonecrosis and the time elapsed from the beginning of treatment with bisphosphonates infusions to surgical procedures.

Atypical Fracture of the Scapular Spine: A Case Report

Atypical fractures are gaining attention as a severe potential side effect of long-term treatment with bone-modifying agents (e.g., bisphosphonate and denosumab) for osteoporosis. Most atypical fractures occur in weight-bearing bones; the femur is the most frequent site. Atypical fractures occurring in non-weight-bearing bones are extremely rare. We describe an atypical fracture of the scapular spine in a 92-year-old Japanese woman with osteoporosis who had been treated with minodronate for ~7 years. Although the dislocation of the fracture site remained after conservative treatment, there was no obstacle to her daily life.

Dentists' Intention to Use Teleconsultation for the Treatment of Patients With Osteoporosis: An Online Survey Study

Introduction: To properly combine osteoporosis treatment with dental treatment and to prevent medication-related osteonecrosis of the jaw (MRONJI), a system of communication between health providers can be smoothly made within a short time is required. With the recent increase in the possibility of telemedicine being introduced in Korea, it is expected that the introduction of teleconsultation between health providers treating osteoporosis will reduce the discomfort of patients and health providers and improve satisfaction. In this study, a survey was conducted on the knowledge and experience of MRONJ to find out the willingness of dentists treating osteoporosis patients for teleconsultation. Methods: An online questionnaire-based survey was conducted to investigate the intention for teleconsultation for MRONJ with a total of 516 dentists between September and October 2021. Results: Two-thirds of the respondents had experience of requesting consultation other dentists or doctors for the osteoporosis or MRONJ patients. They answered that the referral letter was the most used consultation request method and that it took a long time to get a reply. As for the intention of teleconsultation, 70% of the respondents answered that they were willing. The more experienced or the higher the educational level, the higher the intention for teleconsultation. Although the intention of dentists for teleconsultation was high, satisfaction with the cost of teleconsultation was low. Discussion: Although dentists' intention to use teleconsultation was high, satisfaction with the cost of medical care for teleconsultation was low, so it seems that this should be coordinated.

Asia-Pacific consensus on long-term and sequential therapy for osteoporosis

Objectives

This study aimed to present the Asia-Pacific consensus on long-term and sequential therapy for osteoporosis, offering evidence-based recommendations for the effective management of this chronic condition. The primary focus is on achieving optimal fracture prevention through a comprehensive, individualized approach.

Methods

A panel of experts convened to develop consensus statements by synthesizing the current literature and leveraging clinical expertise. The review encompassed long-term anti-osteoporosis medication goals, first-line treatments for individuals at very high fracture risk, and the strategic integration of anabolic and antiresorptive agents in sequential therapy approaches.

Results

The panelists reached a consensus on 12 statements. Key recommendations included advocating for anabolic agents as the first-line treatment for individuals at very high fracture risk and transitioning to antiresorptive agents following the completion of anabolic therapy. Anabolic therapy remains an option for individuals experiencing new fractures or persistent high fracture risk despite antiresorptive treatment. In cases of inadequate response, the consensus recommended considering a switch to more potent medications. The consensus also addressed the management of medication-related complications, proposing alternatives instead of discontinuation of treatment.

Conclusions

This consensus provides a comprehensive, cost-effective strategy for fracture prevention with an emphasis on shared decision-making and the incorporation of country-specific case management systems, such as fracture liaison services. It serves as a valuable guide for healthcare professionals in the Asia-Pacific region, contributing to the ongoing evolution of osteoporosis management.

Preoperative Assessment of Medication-Related Osteonecrosis of the Jaw Using [18F]fluoride Positron Emission Tomography (PET)/CT and [18F]fluorodeoxyglucose PET/MRI in Correlation with Histomorphometry and Micro-CT-A Prospective Comparative Study

OBJECTIVES

The purpose of this study was to investigate the imaging characteristics of medication-related osteonecrosis of the jaw (MRONJ) using [18F]fluoride positron emission tomography/computed tomography (PET/CT) and [18F]fluorodeoxyglucose (FDG) PET/magnetic resonance imaging (MRI) for preoperative assessment and to correlate them with microarchitectural and histomorphometric data with respect to clinical findings.

METHODS

Twelve patients (five female; mean age 75 ± 7.6 yr) with symptomatic MRONJ underwent both scans on the same day, and imaging findings were used to plan surgical interventions for seven patients. Bone tracer uptake was classified as high, medium, or low, and surgical samples were evaluated using Micro-CT and histomorphometric analysis.

RESULTS

CT showed medullary sclerosis in all patients, and MRI revealed gadolinium enhancement in four patients. PET imaging revealed remarkably elevated [18F]fluoride uptake and moderately increased [18F]FDG uptake in MRONJ compared to healthy jawbones, with both differences being statistically significant. [18F]fluoride uptake was associated with necrosis, bacteria, and inflammatory tissue. Micro-CT data did not show significant differences, but histomorphometric analysis revealed higher osteocyte and lacunae densities in the high [18F]fluoride uptake group, and more necrotic bone in the medium [18F]fluoride uptake group. Bacteria were observed in all areas.

CONCLUSIONS

In summary, [18F]fluoride PET accurately identified MRONJ extent, revealing functional changes in jawbone remodeling not visible on CT. [18F]FDG PET showed differences in bone and soft tissue, though less pronounced. This method aids in evaluating disease activity and guiding treatment planning, requiring further research for optimal surgical approaches based on tracer uptake.

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.

Pathological mandibular fracture complicated by osteonecrosis in an adult patient with pycnodysostosis: clinical report and review of the literature

Pycnodysostosis is an ultra-rare osteosclerotic skeletal disorder characterized by short stature, susceptibly to fractures, acroosteolysis of the distal phalanges, and craniofacial features (frontal bossing, prominent nose, obtuse mandibular angle, micrognathia). Dental abnormalities (delayed eruption of teeth, hypodontia, malocclusion, dental crowding, persistence of deciduous teeth, enamel hypoplasia, and increased caries) are also frequent; due to bone metabolism alteration, the patients have an increased risk for jaw osteomyelitis, especially after tooth extraction or mandible fracture. Other complications are obstructive sleep apnea, endocrine alterations and cytopenia. Pycnodysostosis is caused by biallelic loss of function variants in CTSK gene, coding the lysosomal protease cathepsin K. CTSK is involved in the degradation of bone matrix proteins, such as type I and type II collagen. In pycnodysostosis, this degradation is decreased, leading to increased bone density and bone fragility with pathological fractures and poor healing. We present a clinical report of a female adult patient with typical pycnodysostosis phenotype. At the age of 52 years, she had a pathological spontaneous fracture of the right mandible complicated by osteonecrosis, treated with load bearing osteosynthesis. The direct sequencing of CTSK gene revealed the presence of the pathogenic homozygous variant c.746T>A, (p.Ile249Asn), that confirmed the diagnosis of pycnodysostosis. We also review the literature case series published to date, that suggest to always consider the diagnosis of pycnodysostosis in case of osteosclerosis, even in the absence of brachydactyly or short stature. This report details the natural history of the disease in this patient, from childhood to adulthood, and highlights the importance of a quality of life assessment. In addition, we describe a case of mandibular osteonecrosis and spontaneous fracture in pycnodysostosis, drawing attention on the maxillofacial complications in these patients and on the importance of a personalized follow-up.

Risk factors associated with prognosis of patients with medication-related osteonecrosis of the jaw

OBJECTIVES

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse effect of antiresorptive and/or antiangiogenic agents. As the treatment application for MRONJ is controversial, we aimed to identify the risk factors for poor prognosis and to help determine appropriate management.

METHODS

This study included 119 patients. Relevant clinical data were obtained for all the patients. In computed tomography images, osteosclerosis, osteolysis, cortical perforation (buccal or lingual), periosteal reaction, and sequestration were evaluated.

RESULTS

Multivariate analyses showed statistically significant associations between poor prognosis in patients with MRONJ and conservative treatment alone (hazard ratio [HR] 1.89), osteolysis (HR 4.67), and the absence of sequestration (HR 5.33).

CONCLUSIONS

Conservative treatment alone without clear objectives needs to be avoided, and osteolytic change could be the criteria for surgical intervention. As the boundary between the lesion and vital bone is indistinct, we recommend extensive surgery in cases with unpredictable sequestration.

Medication-related osteonecrosis of the lower jaw without osteolysis on computed tomography images

INTRODUCTION

Surgery is the standard treatment for medication-related osteonecrosis of the jaw (MRONJ). This study reviewed patients with mandibular MRONJ who underwent surgical treatment, and in particular the characteristics of non-osteolytic MRONJ with no evidence of osteolysis on CT were described.

MATERIALS AND METHODS

We conducted a retrospective study of patients with mandibular MRONJ who underwent surgery between January 2016 and September 2022. Various clinical and imaging factors regarding treatment outcomes were investigated and analyzed. Additionally, the disease course of non-osteolytic MRONJ was examined in detail.

RESULTS

This study included 55 patients (66 surgeries) with a mean age of 74.7. The primary disease was osteoporosis (24 patients) and malignancy (31 patients); the type of antiresorptive agent was bisphosphonate (BP) in 21 patients and denosumab (DMB) in 26. BP was initially administered; however, it was changed to DMB in eight patients. Preoperatively, the cumulative cure rates for all 66 surgeries were 72.8% at 1 year and 77.3% at 2 years. Cure rates were significantly lower in patients with malignancy, those without osteolysis, and those who underwent sequestrum removal or marginal mandibulectomy than those with osteoporosis, osteolysis, and segmental mandibulectomy. Non-osteolytic MRONJ was observed in eight patients, all with malignancy and receiving high-dose DMB. Only two patients were cured after the initial surgery, and most patients ultimately underwent segmental mandibulectomy.

CONCLUSIONS

Surgical treatment yielded good treatment outcomes in most patients with mandibular MRONJ; however, the cure rate was lower in patients with malignancy who showed no osteolysis on CT images.

Is withdrawal of antiresorptive agents necessary before and after tooth extraction? A systematic review

OBJECTIVES

The need for prevention and management of medication-related osteonecrosis of the jaw (MRONJ) has increased with the growing number of patients using antiresorptive agents. The scope of this systematic review (SR) was to determine whether the withdrawal of antiresorptive agents is necessary for tooth extractions in patients receiving each of the antiresorptive medications.

MATERIALS AND METHODS

The searches were performed using the MEDLINE databases. We selected SRs, randomized controlled trials (RCTs), prospective and retrospective non-randomized clinical (observational) studies, and case reports/case series in this order of preference.

RESULTS

We included one SR, one RCT, five observational studies, and three case reports. Meta-analyses were not conducted because the RCT had an extremely small sample size and the observational studies had different definitions of intervention and comparison that could not be integrated across studies. In this SR, no studies showed a benefit (i.e., a reduction in the incidence of osteonecrosis of the jaw) of short-term withdrawal of antiresorptive agents for tooth extraction. Additionally, no studies examined the harm (i.e., an increase in femoral and vertebral fractures and skeletal-related events during bone metastasis) of withdrawal for tooth extraction.

CONCLUSIONS

We were unable to determine whether withdrawal before and after tooth extraction is necessary with a high certainty of evidence. Future systematic reviews including RCTs with larger samples are expected to provide such evidence.

CLINICAL RELEVANCE

This systematic review provides evidence-based information for multidisciplinary collaborations related to patients receiving antiresorptive agents.

Antiresorptive agent-related osteonecrosis of the jaw risk in cancer patients before bone-modifying agent therapy: A retrospective study of 511 patients

INTRODUCTION

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is a serious adverse event associated with therapies for advanced cancer involving bone-modifying agents (BMAs). Although many studies have investigated the risk factors for ARONJ, none have provided sufficient clarifications. We aimed to determine whether there is a correlation between tooth extraction before BMA therapy and the development of ARONJ.

PATIENTS AND METHODS

We included 511 patients who were admitted to our department before BMA therapy. The incidence of ARONJ and its risk factors was retrospectively evaluated, focusing on tooth extraction before BMA therapy and radiological findings of the extracted tooth.

RESULTS

Of the 511 patients, 135 underwent tooth extraction before undergoing BMA therapy. ARONJ was observed in 17.7 % and 7.2 % of patients in the extraction and non-extraction groups, respectively (p = 0.0002). Regarding the findings of panoramic radiographs before tooth extraction, the incidence of periapical disease was significantly higher in the ARONJ group than that in the non-ARONJ group (50 % and 27 %, respectively, p = 0.034), and the proportion of bone sclerotic changes in the surrounding teeth was significantly higher in the ARONJ group (58.3 %) than in the non-ARONJ group (24.4 %) (p = 0.0004).

CONCLUSION

The presence of a hopeless tooth that requires extraction prior to BMA therapy is a risk factor for MRONJ. However, extraction of such teeth should be considered, as this is known to decrease the risk of MRONJ development after BMA therapy initiation. Moreover, the radiological findings of periapical disease and bone sclerotic changes in the extracted teeth identified in this study can be used as novel predictive factors for ARONJ.

Cooperation between physicians and dentists for osteonecrosis of the jaw: a 2022 Japanese survey

INTRODUCTION

A 2015 survey of the Japan Osteoporosis Society (JOS) on medication-related osteonecrosis of the jaw (MRONJ) revealed that cooperation between physicians and dentists was poor. Discontinuation of antiresorptive agents before tooth extraction was found to increase adverse events without preventing MRONJ. We compared this 2015 survey with a new survey conducted in 2022 to investigate cooperation between physicians and dentists for MRONJ.

MATERIALS AND METHODS

A web-based structured questionnaire including 13 key queries was sent to 3813 physicians who were members of JOS, and 1227 (32.2%) responses were received.

RESULTS

Of the 1227 respondents, 909 (74.1%) had complied with a discontinuation request from a dentist before tooth extraction, although 25.4% of medications were not related to the incidence of MRONJ. Of these, 177 respondents reported 252 adverse events including 10 (1.3%) cases of MRONJ. The prevalence of fractures increased from 4.8% in 2015 to 8.2% in 2022. The rates of respondents who requested oral health care by a dentist before antiresorptive agent therapy and reported cooperation between physicians and dentists were 72.7% and 42.4% in 2022 compared with 32.9% and 24.8% in 2015, respectively. The rates of cooperation among the 47 prefectures in Japan were significantly different, ranging from 10.0 to 83.3% (p = 0.02).

CONCLUSION

This study confirmed increased cooperation between physicians and dentists for MRONJ in Japan. However, a more equal distribution of cooperation across Japan is necessary to optimally manage MRONJ. Discontinuation of antiresorptive agents is no longer necessary because fractures during discontinuation continue to increase in Japan.

How does the clinical and tomographic appearance of MRONJ influences its treatment prognosis?

OBJECTIVES

To identify clinical and tomographic prognostic factors for conservative and surgical treatment of medication-related osteonecrosis of the jaws (MRONJ).

METHODS

A retrospective search identified patients treated with antiresorptive drugs (ARDs), diagnosed with Stage 1, 2 or 3 MRONJ, and having CBCT scans previous to conservative or surgical treatment. Following data collection, imaging assessment of the following parameters on each MRONJ site was performed: involvement of teeth and/or implants, presence of osteosclerosis, osteolysis, sequestrum formation, periosteal reaction, and pathological fractures. For statistical analysis, patients and lesions were divided into conservative and surgical treatment. Comparisons were made between successful and unsuccessful outcomes. Significance was set at p ≤ 0.05.

RESULTS

115 ARD-treated patients who developed 143 osteonecrosis lesions were selected. 40 patients and 58 lesions received conservative treatment, of which 14 patients (35%) and 25 lesions (43%) healed. Additionally, 75 patients and 85 lesions underwent surgery, with 48 patients (64%) and 55 lesions (65%) that healed. Clinical and tomographic risk factors for conservative treatment were MRONJ staging, tooth involvement, extensive osteosclerosis, and deep sequestrum formation (p < 0.05). Complementarily, poor prognostic indicators for surgical therapy were a short bisphosphonate (BP) holiday, MRONJ staging, absence of sequestrum formation, and presence of periosteal reaction (p < 0.05).

CONCLUSIONS

Lesions at Stage 3 MRONJ, with tooth involvement, or sequestrum formation showed poor outcomes when conservative treatment is chosen. Alternatively, surgical treatment is most effective when BPs are discontinued, in Stage 1 lesions, in the presence of sequestrum formation, and absence of periosteal reaction.

Bisphosphonates and osteonecrosis of the jaws: Clinical and forensic aspects

OBJECTIVE

This manuscript aims to provide a comprehensive review of the current knowledge in the pathophysiology, diagnosis, prevention, and other relevant clinical and forensic aspects of a potentially severe complication known as medication-related osteonecrosis of the jaw (MRONJ) while synthesizing state-of-the-art information on bisphosphonates and introducing a possible differential diagnosis.

DESIGN

An extensive search was conducted in PubMed (U.S. National Library of Medicine) without a time or language constraint, focusing on the epidemiology, pathophysiology, risk factors, site specificity, signs and symptoms, differential diagnosis, prevention, and forensic aspects of MRONJ. All types of original articles, reviews, case reports, short communications, opinion articles, guidelines, and letters to editors were considered to produce a complete review on this subject.

RESULTS

MRONJ prevention relies on a multidisciplinary approach and is critical since truly effective treatments are lacking. This therapeutic challenge is partly due to uncertainty regarding this condition's pathophysiology. Differential diagnosis of osteonecrosis of the jaws associated with krokodil abuse, one of the most dangerous and homemade psychoactive illicit substances, should be considered.

CONCLUSIONS

Further research into the etiology and site specificity of MRONJ is encouraged, aiming to develop novel treatment prospects. Indeed, comprehending this would allow for increased efficacy and therapeutic options while emphasizing the importance of prevention. In addition, we advocate for greater consensus among the various societies regarding MRONJ's treatment and management.

Reliability of early stage symptoms/clinical findings of osteonecrosis of the jaw: Japanese Osteoporosis Intervention Trial-05 (JOINT-05)

INTRODUCTION

To investigate the differences in the incidence rates of suspected stage 0/1 osteonecrosis of the jaw (ONJ) and incidence risk of relevant clinical findings of suspected stage 0 ONJ between patients treated with sequential therapy comprising weekly teriparatide for 72 weeks followed by alendronate for 48 weeks vs. those who received monotherapy with alendronate for 120 weeks.

MATERIALS AND METHODS

Suspected stage 0/1 ONJ was defined by non-specific symptoms. Tooth mobility and periodontal symptoms (gingival bleeding, swelling, and/or pain) were selected as clinical findings of suspected stage 0 ONJ. Poisson regression models were applied to calculate the incidence rate ratios of suspected stage 0/1 between the teriparatide group (TG) and alendronate group (AG). Generalized linear models were used to calculate the risk ratios of clinical findings between groups.

RESULTS

Two hundred and sixty-one participants in the TG and 344 in the AG answered a structured questionnaire on oral health and were included in this study. There were no significant differences between the groups in the incidence rate of suspected stage 0/1 ONJ at both 72 and 120 weeks. The risk ratio of the TG to AG for tooth mobility was 0.34 (95% confidence interval [CI] 0.13-0.88, p = 0.02) at 72 weeks and 0.90 (95% CI 0.40-2.03, p = 0.83) at 120 weeks. The incidence rate of tooth mobility related to periodontal symptoms decreased in the TG and increased in the AG during the study.

CONCLUSION

Tooth mobility accompanied by clinical periodontal symptoms may be a useful early sign of stage 0 ONJ.

Medication-related Osteonecrosis of the Jaw Induced by Regenerative Therapy in Implant Dentistry: A Scoping Review

OBJECTIVES

There is limited scientific evidence regarding the medication-related osteonecrosis of the jaw (MRONJ) induced by regenerative therapy (RT) associated with dental implant treatment. Thus, the current scoping review systematically maps the MRONJ research induced by RTs in implant dentistry and recognizes the existing gaps in knowledge.

DATA

Original studies and reviews investigating the impact of RT on the development of MRONJ were included.

SOURCES

Two reviewers independently searched the MEDLINE-PubMed and Scopus databases according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) extension for Scoping Review and included articles published in English up to March 31, 2023.

STUDY SELECTION

Eighteen articles that fulfilled the inclusion and exclusion criteria were included in this study. Ten mapping parameters for investigating the association of RTs with MRONJ development were examined and evaluated within the selected articles.

RESULTS

There was severely limited information regarding the procedures of RTs including; the grafting materials, surgical protocols, and success and failure rates. The RT associated with MRONJ cases was sinus floor augmentation in patients taking bisphosphonate and denosumab. Moreover, there were limited data on the implant treatment associated with RTs such as time of insertion, implant length and diameter, and loading protocol.

CONCLUSION

The current scoping review revealed that some specific RTs associated with other factors hold a potential risk of MRONJ occurrence. However, the scientific evidence is limited with many gaps. Further investigations are needed to establish an evidence-based clinical guideline for treating high-risk patients.

CLINICAL SIGNIFICANCE

Clinicians should cautiously assess the risk of MRONJ development during implant treatment planning for patients undertaking antiresorptive medications. The adverse outcome of RT procedures should not be underestimated and a complete explanation of the possible risks should be given to the patients.

Awareness and practice of dentists in gulf cooperation council countries regarding medication-related osteonecrosis of the jaw - A web-based survey

Background/purpose

Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication among dental patients undergoing treatment with antiresorptive medications such as bisphosphonate and denosumab. The present survey investigated the awareness and practice of dentists in the Gulf Cooperation Council (GCC) countries regarding MRONJ.

Materials and methods

This questionnaire-based study was conducted among dental practitioners in all six GCC countries. A questionnaire was designed and distributed among all potential participants via different social media platforms. SPSS version 22 was used for data analysis, and P-value <0.05 was considered statistically significant.

Results

Overall, 1685 dentists from the six GCC countries participated in the present study. The surveyed dentists revealed relatively fair practices and awareness regarding MRONJ and its prevention, with the majority reported asking their patients about history of anti-osteoporotic medications (67.8%), recording name of the medication (73.1%) and duration of treatment (75.5%). However, the majority of the participants were unconfident about the duration of drug holiday prior to dental surgical interventions (70.6%) and the overall good level of knowledge/practice related to MRONJ was just 50.6%. The regression analysis revealed that previous exposure to MRONJ cases and attending a seminar, course, meeting, or conference about osteonecrosis of the jaw were independent predictors for positive awareness/good practice regarding MRONJ (P < 0.05).

Conclusion

The results show inadequate awareness and practices of dentists practicing in GCC countries regarding MRONJ, with significant variations among the countries. Therefore, appropriate interventions such as periodic continuous education courses are required to improve dentists' knowledge and practices regarding MRONJ.

A Case Report of Ibandronic Acid Induced Non-Exposed BRONJ Involving the Maxillary Sinus

Background

The aim of this case report is to present an interesting case of bisphosphonate-related osteonecrosis of the jaw, involving the maxilla and the maxillary sinus, as a result of per os administration of ibandronic acid.

Methods

A female patient, 62 years old, was referred to the Department of Dentoalveolar Surgery, Surgical Implantology and Radiology, School of Dentistry, Aristotle University of Thessaloniki, Greece, complaining about pain in the first quadrant. Her medical history revealed per os bisphosphonate administration for the past four years. Subsequently, the cone-beam computed tomography examination revealed a small sequestrum of bone, surrounded by radiolucency, in proximity with the sinus floor. The clinical examination didn't reveal any pathological clinical signs.

Results

Based on the radiological examination, a surgical approach was implemented to remove the necrotic bone, irrigate the alveolar process and the sinus with saline, and finally achieve primary closure, after which, the patient healed uneventfully. The osteonecrosis was attributed to the bisphosphonate administration.

Conclusions

Bisphosphonate-related osteonecrosis of the jaw without obvious or with minor implication of gingival tissues is a diagnostic challenge indicating an early stage of this adverse reaction. Imaging is critical for the early detection of those cases. After careful choice of the case the proper surgical intervention could be effective to eliminate a future advancement of bone destruction. The prevention of osteonecrosis of the jaw can be achieved through the provision of adequate education to dental medicine practitioners, medical doctors, and patients.

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

Background/purpose

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

Materials and methods

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

Results

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

Conclusion

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

Risk comparison of osteonecrosis of the jaw in osteoporotic patients treated with bisphosphonates vs. denosumab: a multi-institutional retrospective cohort study in Taiwan

In this multi-institutional retrospective cohort study, we compared the long-term risk of osteonecrosis of the jaw following the use of denosumab vs. bisphosphonates in osteoporotic patients. After 2-year use, the likelihood of osteonecrosis of the jaw is lower with denosumab compared to bisphosphonates, and the difference increases with time.

PURPOSE

To compare the long-term risk of osteonecrosis of the jaw (ONJ) between osteoporotic patients treated with bisphosphonates (BPs) and denosumab.

METHODS

This multi-institutional retrospective cohort study included patients aged > 40 years with osteoporosis between January 2010 and December 2018. Patients who met the eligibility criteria were divided into BPs and denosumab groups by propensity score matching (PSM). The risk of ONJ of denosumab vs. BPs was estimated using a Cox proportional hazards model and was described by the cumulative incidence rate using the Kaplan-Meier method.

RESULTS

A total of 84,102 patients with osteoporosis were enrolled, among whom, 8962 were eligible for inclusion based on their first-line drug use (denosumab, n = 3,823; BPs, n = 5,139). Following PCM matching (1:1), the BPs and denosumab groups included 3665 patients each. The incidence density of ONJ in the denosumab and BPs matching groups was 1.47 vs. 2.49 events (per 1000 person-years), respectively. The hazard ratio of ONJ in the denosumab vs. BPs group was estimated as 0.581 (95% confidence interval: 0.33-1.04, p = 0.07). The cumulative incidence rates of ONJ in both groups were similar for the first and second years of drug use (p = 0.062), but significantly different from the third year onwards (p = 0.022). The severity of ONJ was not significantly different between the two groups.

CONCLUSION

In osteoporotic patients, after 2 years of use, the likelihood of ONJ being induced by denosumab is lower than that of BPs, and the difference increases with time.

Impact of beta-tricalcium phosphate on preventing tooth extraction-triggered bisphosphonate-related osteonecrosis of the jaw in rats

Antiresorptive or antiangiogenic drugs can cause medication-related osteonecrosis of the jaw that is refractory. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) may be caused by procedures such as tooth extraction damage the alveolar bone, release bisphosphonates (BPs) and impede healing. This study investigated strategies for BRONJ prevention and molecular mechanisms of its onset. We assessed the effectiveness of filling extraction sockets with beta-tricalcium phosphate (β-TCP). Rats were administered zoledronic acid (ZA) 1.2 mg/kg once per week for 2 weeks, and a molar was extracted. They were randomly assigned to the β-TCP group (bone defects filled with 0.01 g of β-TCP) or control group. Tissue content measurements indicated 2.2 ng of ZA per socket in the β-TCP group and 4.9 ng in the control group, confirming BP distribution and BP adsorption by β-TCP in vivo. At 4 weeks after extraction, the β-TCP group had normal mucosal coverage without inflammation. Moreover, at 8 weeks after extraction, enhanced bone healing, socket coverage, and new bone formation were observed in the β-TCP group. Connective tissue in the extraction sockets suggested that local increases in BP concentrations may suppress the local autophagy mechanisms involved in BRONJ. Filling extraction sockets with β-TCP may prevent BRONJ.

Management of bone metastasis in prostate cancer

Progression of bone metastases is the primary cause of death in prostate cancer, and skeletal-related events (SREs), including pathologic fractures, spinal cord compression, radiation, or surgery to bone can impair patients' quality of life. Over the past decade, the development of cytotoxic agents, androgen-receptor-axis-targeted therapies (ARATs), and radioligand therapies has prolonged overall survival of prostate cancer patients with bone metastases and reduced the risk of SREs. The use of bone-modifying agents has also contributed to the reduced risk of SREs. Initial use of a cytotoxic agent, docetaxel, or an ARAT agent with androgen deprivation therapy (ADT) is the current approach to metastatic castration-sensitive prostate cancer. However, there is no consensus on the optimal medication for upfront use in combination with ADT, or on specific patient selection. Recently, next-generation imaging modalities, such as whole-body magnetic resonance imaging and prostate-specific membrane antigen-positron emission tomography have been utilized to detect bone metastases at an early stage. In addition, metastasis-directed therapy, such as stereotactic body radiation therapy, has been attempted. In the future, patients with bone metastatic prostate cancer will be divided into subgroups and their treatment options will be tailored to their specific characteristics.

Diagnostic accuracy comparing OPT and CBCT in the detection of non-vital bone changes before tooth extractions in patients with antiresorptive intake

OBJECTIVES

To compare the diagnostic accuracy in detecting early non-vital bone changes between orthopantomography (OPT) and cone-beam computed tomography (CBCT) in correlation with histopathological findings before tooth extractions in patients with antiresorptive (AR) intake.

SUBJECTS

Patients with an indication tooth extraction who had received OPT and CBCT preoperatively while or after undergoing AR treatment were prospectively enrolled over a 24-month period in the progesterone in spontaneous miscarriage (PRISM) trial. Imaging studies were randomly analyzed by three examiners for early non-vital bone changes using specific predefined characteristics and a 5-level scale (1 definite absence of criteria to 5 definite presence of criteria). Sensitivity and specificity values were calculated in correlation with the histopathologically evaluated bone samples at the time point of tooth extraction.

RESULTS

One hundred thirty patients with 237 treated extraction sites met the inclusion criteria. For all images evaluated by all examiners, CBCT (430/492; 87.4%; receiver operating characteristic [ROC]: area under the curve [AUC] = 0.88; p < 0.001) was more likely to detect histopathologically confirmed non-vital bone than the OPT (132/492; 26.8%; ROC: AUC = 0.562; p = 0.115).

CONCLUSIONS

In the detection of non-vital bone changes, CBCT is superior to OPT in both sensitivity and specificity. Specific imaging characteristics allow for the prediction of early non-vital bone changes already at the time before tooth extractions.

Differences between zoledronic acid and denosumab for breast cancer treatment

Zoledronic acid and denosumab are bone-modifying agents that are clinically important in multiple aspects of bone management for breast cancer patients. These aspects include the prevention of osteoporosis induced by cancer-treatment bone loss, treatment and prevention of bone metastasis, and improvement of survival directly or indirectly by maintaining bone health. Interestingly, zoledronic acid and denosumab have different anticancer activities, and they may be associated with the improvement of survival of breast cancer patients under different mechanisms. Zoledronic acid is the most potent bisphosphonate. It provides significant benefits for improving breast cancer mortality in patients with suppressed estrogen level such as in postmenopausal or ovarian suppression condition. Although denosumab's anticancer activity has not been clearly proven compared with zoledronic acid's anticancer activity, denosumab is promising in preventing BRCA1 mutant breast cancer because RANKL is a targetable pathway in BRCA1-associated tumorigenesis. Further studies and more effective clinical use of these agents are anticipated to contribute to the improvement of the clinical outcome of breast cancer patients.

Zoledronate/Anti-VEGF Neutralizing Antibody Combination Administration Increases Osteal Macrophages in a Murine Model of MRONJ Stage 0-like Lesions

The pathophysiology, pathogenesis, histopathology, and immunopathology of medication-related osteonecrosis of the jaw (MRONJ) Stage 0 remain unclear, although 50% of MRONJ Stage 0 cases could progress to higher stages. The aim of this study was to investigate the effects of zoledronate (Zol) and anti-vascular endothelial cell growth factor A (VEGFA) neutralizing antibody (Vab) administration on polarization shifting of macrophage subsets in tooth extraction sockets by creating a murine model of MRONJ Stage 0-like lesions. Eight-week-old, female C57BL/6J mice were randomly divided into 4 groups: Zol, Vab, Zol/Vab combination, and vehicle control (VC). Subcutaneous Zol and intraperitoneal Vab administration were performed for 5 weeks with extraction of both maxillary first molars 3 weeks after drug administration. Euthanasia was conducted 2 weeks after tooth extraction. Maxillae, tibiae, femora, tongues, and sera were collected. Structural, histological, immunohistochemical, and biochemical analyses were comprehensively performed. Tooth extraction sites appeared to be completely healed in all groups. However, osseous healing and soft tissue healing of tooth extraction sites were quite different. The Zol/Vab combination significantly induced abnormal epithelial healing, and delayed connective tissue healing due to decreased rete ridge length and thickness of the stratum granulosum and due to decreased collagen production, respectively. Moreover, Zol/Vab significantly increased necrotic bone area with increased numbers of empty lacunae compared with Vab and VC. Most interestingly, Zol/Vab significantly increased the number of CD169⁺ osteal macrophages (osteomacs) in the bone marrow and decreased F4/80+ macrophages, with a slightly increased ratio of F4/80⁺CD38⁺ M1 macrophages compared to VC. These findings are the first to provide new evidence of the involvement of osteal macrophages in the immunopathology of MRONJ Stage 0-like lesions.

Nitrogen-Containing Bisphosphonates Downregulate Cathepsin K and Upregulate Annexin V in Osteoclasts Cultured In Vitro

Introduction

Bisphosphonates are widely used in the treatment of osteoporosis; however, they are associated with the serious adverse event of bisphosphonate-related osteonecrosis of the jaw (BRONJ).

Aim

The aim of this study is to assess the effects of nitrogen-containing bisphosphonates (N-PHs) on the synthesis of IL-1β, TNF-α, sRANKL, cathepsin K, and annexin V in bone cells cultured in vitro.

Materials and Methods

Osteoblasts and bone marrow-derived osteoclasts were cultured in vitro, subjected to treatment with alendronate, risedronate, or ibandronate at a concentration of 10^-5 M for 0 to 96 h and then assayed for IL-1β, sRANKL, and TNF-α production by ELISA. Cathepsin K and Annexin V-FITC staining in osteoclasts were assessed by flow cytometry.

Results

There was significant downregulation of IL-1β, sRANKL, and TNF-α in experimental osteoblasts compared to control cells, and there was upregulation of IL-1β and downregulation of RANKL and TNF-α in experimental osteoclasts. Furthermore, in osteoclasts, cathepsin K expression was downregulated at 48-72 h with alendronate treatment, while risedronate treatment resulted in upregulated annexin V expression at 48 h compared to the control treatment.

Conclusion

Bisphosphonates added to bone cells inhibited osteoclastogenesis, which led to the downregulation of cathepsin K and induction of apoptosis in osteoclasts; these changes limited the capacity of bone remodelling and healing that may contribute to BRONJ induced by surgical dental procedures.

Medication-Related Osteonecrosis of the Jaws (MRONJ) in Children and Young Patients-A Systematic Review

Medication-related osteonecrosis of the jaw (MRONJ) is defined by the American Association of Oral and Maxillofacial Surgeons (AAOMS) as the presence of an exposed bone area in the maxillofacial region, present for more than eight weeks in patients treated with the use of antiresorptive or antiangiogenic agents, with no history of radiation or metastatic disease. Bisphosphonates (BF) and denosumab (DS) are widely used in adults for the management of patients with cancer and osteoporosis, and recently there has been an increase in their use in child and young patients for the management of disorders such as osteogenesis imperfecta (OI), glucocorticoid-induced osteoporosis, McCune-Albright syndrome (MAS), malignant hypercalcemia, and others. There are differences between case reports in adults compared to child and young patients related to the use of antiresorptive/antiangiogenic drugs and the development of MRONJ. The aim was to analyze the presence of MRONJ in children and young patients, and the relation with oral surgery. A systematic review, following the PRISMA search matrix based on the PICO question, was conducted in PubMed, Embase, ScienceDirect, Cochrane, Google Scholar, and manual search in high-impact journals between 1960 and 2022, publications in English or Spanish, including randomized and non-randomized clinical trials, prospective and retrospective cohort studies, cases and controls studies, and series and case reports. A total of 2792 articles were identified and 29 were included; all of them published between 2007 and 2022, identifying 1192 patients, 39.68% male and 36.24% female, aged 11.56 years old on average, using these drugs mainly for OI (60.15%); 4.21 years on average was the therapy time and 10.18 drug doses administered on average; oral surgery was observed in 216 subjects, reporting 14 cases of MRONJ. We concluded that there is a low presence of MRONJ in the child and youth population treated with antiresorptive drugs. Data collection is weak, and details of therapy are not clear in some cases. Deficiencies in protocols and pharmacological characterization were observed in most of the included articles.

Bisphosphonates Prescription for Patients With Hip Fractures Based on Evaluation by a Dentist

Background The purpose of this study is to clarify the current status of the prescription of postoperative bisphosphonates for patients with hip fractures and to explore the factors that prevent the postoperative prescription of bisphosphonates. Methods Of 180 patients with hip fractures treated surgically at our hospital between August 2019 and April 2020, 149 patients (46 men and 103 women; mean age: 83.9 ± 9.0 years), excluding 31 patients already prescribed bisphosphonates or denosumab, were included in the study. All patients were treated based on our clinical pathway, and their risk of jaw osteonecrosis was evaluated prior to the initiation of bisphosphonates by a dentist in our hospital. We collected data from the medical records on osteoporosis treatment interventions at admission and discharge, the reasons why postoperative bisphosphonates could not be prescribed at discharge, the proportion of patients who had follow-ups at our hospital, and patients' osteoporosis treatment status. Results Eighteen (12.8%) and 95 (63.8%) patients were prescribed anti-osteoporosis drugs at admission and discharge, respectively. One hundred and twenty-one patients (86.8%) could not be prescribed postoperative bisphosphonates at discharge - 71 (58.7%) because of oral hygiene problems, 34 (28.1%) because they did not have regular dental consultations, seven (5.8%) because of renal dysfunction, eight (6.6%) because of poor cognitive and swallowing function, and one (0.8%) because of medication side effects. Forty-nine patients (32.9%) went to our hospital for follow-up and 11 were introduced to bisphosphonates or denosumab at follow-up. Conclusions The number of patients with hip fractures who were prescribed postoperative bisphosphonates was low in our study. The oral hygiene problems identified by dentists accounted for responsible for the low prescription rate of postoperative bisphosphonates. Therefore, coordination with dentists may be important to increase the postoperative bisphosphonate prescription.

Comparing the Influence of Surgical and Conservative Therapy on Quality of Life in Patients with Early-Stage Medication-Related Osteonecrosis of the Jaw-A Prospective Longitudinal Study

Background and Objectives: The purpose of this study was to evaluate the impact of surgical and conservative, non-surgical treatment on general health-related (QoL) and oral health-related quality of life (OHRQoL) in patients suffering from AAOMS stage I MRONJ. Materials and Methods: In the course of this prospective clinical study, QoL and OHRQoL using QLQ-C30 and QHIP G14 questionnaire were longitudinally assessed in N = 174 prospectively enrolled patients with indication of treatment of MRONJ stage I over a period of 12 months. Patients received conservative or surgical treatment. The measurement time points were preoperatively (T0), 12 weeks (T1), 6 months (T2) and 1 year after operation (T3). Results: For OHRQoL, no significant (p > 0.05) differences were found between both treatment groups for all timepoints (T0-T3). In the surgical treatment group, OHIP scores of T1, T2 and T3 were significantly lower than baseline measures (T0) (T0-T1 (2.99, p = 0.024), T0-T2 (5.20, p < 0.001), T0-T3 (7.44, p < 0.001)). For conservative treatment group OHIP, scores of T2 and T3 were significantly lower than baseline measures (T0) (T0-T2 (9.09, p = 0.013), T0-T3 (12.79, p < 0.001)). There was no statistically significant effect of time on QLQ-C30 scores in both groups (surgical treatment: F(3, 174) = 1.542, p < 0.205, partial η² = 0.026; conservative treatment: F(3, 30) = 0.528, p = 0.667, partial η² = 0.050). QLQ-C30 scores turned out to be significantly lower in the non-surgical group at T1 (p = 0.036) and T3 (p = 0.047) compared to the surgical treatment group. Conclusions: Surgical and conservative treatment of MRONJ stage I significantly improves patients' OHRQoL. Surgical treatment is superior to conservative treatment of MRONJ stage I regarding general QoL. Therefore, surgical treatment of MRONJ stage I should not be omitted for QoL reasons.