Diagnosis and management of osteonecrosis of the jaw: a systematic review and international consensus

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.

Raman spectroscopy and U-Net deep neural network in antiresorptive drug-related osteonecrosis of the jaw

OBJECTIVE

Application of an optical method for the identification of antiresorptive drug-related osteonecrosis of the jaw (ARONJ).

METHODS

We introduce shifted-excitation Raman difference spectroscopy followed by U-Net deep neural network refinement to determine bone tissue viability. The obtained results are validated through established histological methods.

RESULTS

Discrimination of osteonecrosis from physiological tissues was evaluated at 119 distinct measurement loci in 40 surgical specimens from 28 patients. Mean Raman spectra were refined from 11,900 raw spectra, and characteristic peaks were assigned to their respective molecular origin. Then, following principal component and linear discriminant analyses, osteonecrotic lesions were distinguished from physiological tissue entities, such as viable bone, with a sensitivity, specificity, and overall accuracy of 100%. Moreover, bone mineral content, quality, maturity, and crystallinity were quantified, revealing an increased mineral-to-matrix ratio and decreased carbonate-to-phosphate ratio in ARONJ lesions compared to physiological bone.

CONCLUSION

The results demonstrate feasibility with high classification accuracy in this collective. The differentiation was determined by the spectral features of the organic and mineral composition of bone. This merely optical, noninvasive technique is a promising candidate to ameliorate both the diagnosis and treatment of ARONJ in the future.

Photodynamic therapy repairs medication-related osteonecrosis of the jaw by reducing NF-kB protein in rats

OBJECTIVE

To evaluate whether antimicrobial photodynamic therapy (aPDT) repairs bisphosphonate-related osteonecrosis of the jaw (BRONJ) modulated by the reduction of NF-kB protein in a murine model.

METHODOLOGY

Male Wistar rats (N=30) were divided into the following groups (n=6/group): negative control (NC); experimental osteonecrosis (ONE); ONE + photosensitizer (PS); ONE + photobiomodulation (PBM); and ONE + aPDT. Over 8 weeks, ONE was induced by zoledronic acid 250 µg/kg injections, except in the NC group, which received sterile 0.9% saline, followed by extraction of the lower left first molar. Red light laser irradiation (wavelength ~660 nm, power 50 mW, energy of 2 J, energy dose of 66.67 J/cm2 for 40 s) was performed once a week for 4 weeks. Methylene blue 0.3% was used as PS. The animals were euthanized and examined macroscopically for the presence of exposed bone and epithelial repair and microscopically by histochemical (hematoxylin-eosin and Masson's trichrome staining) and immunohistochemical (anti-NF-kB) methods. Macroscopic and histomorphometric data were analyzed by one-way ANOVA and Tukey's post-test (p<0.05).

RESULTS

Mucosal repair, viable osteocytes, and NF-kB immunostaining were observed in the NC, ONE+PS, ONE+PBM, and ONE+aPDT groups. The ONE group showed no mucosal repair, showing empty lacunae and multifocal immunostaining for NF-kB. The ONE+PBM and ONE+aPDT groups had greater deposition of extracellular matrix and less necrotic bone tissue (p<0.05).

CONCLUSION

PBM and aPDT treatments for BRONJ were effective for bone and epithelial repair, in addition to reducing inflammation mediated by the decrease of NF-kB protein in the irradiated regions.

Radiological manifestations and clinical findings of patients with oncologic and osteoporotic medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) poses a challenging form of osteomyelitis in patients undergoing antiresorptive therapies in contrast to conventional osteomyelitis. This study aimed to compare the clinical and radiological features of MRONJ between patients receiving low-dose medications for osteoporosis and those receiving high-dose medications for oncologic purposes. The clinical, panoramic radiographic, and computed tomography data of 159 patients with MRONJ (osteoporotic group, n = 120; oncologic group, n = 39) who developed the condition after using antiresorptive medications for the management of osteoporosis or bone malignancy were analyzed. The osteoporotic group was older (75.8 vs. 60.4 years, p < 0.01) and had a longer duration of medication usage than the oncologic group (58.1 vs. 28.0 months, p < 0.01). Pus discharge and swelling were more common in the osteoporotic group (p < 0.05), whereas bone exposure was more frequent in the oncologic group (p < 0.01). The mandibular cortical index (MCI) in panoramic radiographs was higher in the osteoporotic group (p < 0.01). The mean sequestra size was larger in the oncologic group than in the osteoporotic group (15.3 vs. 10.6 mm, p < 0.05). The cured rate was significantly higher in the osteoporotic group (66.3% vs. 33.3%, p < 0.01). Oncologic MRONJ exhibited distinct clinical findings including rapid disease onset, fewer purulent signs, and lower cure rates than osteoporotic MRONJ. Radiological features such as sequestrum size on CT scan, and MCI values on panoramic radiographs, may aid in differentiating MRONJ in osteoporotic and oncologic patients.

Is maxillary sinusitis and radiographic maxillary sinus opacification associated with an altered microbiology of MRONJ?

OBJECTIVE

Maxillary sinusitis can be a sequela of medication-related osteonecrosis of the jaw (MRONJ). This study aims to characterize the microbiome of maxillary MRONJ with concurrent maxillary sinusitis and radiographic maxillary sinus opacification to determine if there is a relationship between the microbiome of MRONJ and sinus disease.

STUDY DESIGN

This retrospective case series was conducted using electronic health records from the University of Pennsylvania and affiliated hospitals. The target population was surgically managed maxillary MRONJ patients. The primary predictor variables were tissue culture results. The primary outcomes were maxillary sinusitis or maxillary sinus opacification. Statistical analysis was performed using chi-squared tests at the 95% confidence interval.

RESULTS

Thirty-nine subjects were selected: 25 had sinus opacification and 11 had sinusitis. Resident bacteria were present in 90% of subjects, nonresident bacteria in 74%, and opportunistic organisms in 15%. There were significantly more subjects with chronic sinusitis microbes (79%) than without. There were significantly more gram-positive anaerobes, specifically Propionibacterium, as well as the gram-negative facultative anaerobe, Capnocytophaga, in subjects with concurrent sinusitis.

CONCLUSIONS

Maxillary MRONJ with concurrent maxillary sinusitis may be associated with gram-positive anaerobic species, Propionibacterium, and Capnocytophaga colonization. Maxillary MRONJ patients may benefit from sinus evaluation and concurrent surgical intervention.

The Current Status of Utilizing a Medication Record Handbook for Evaluating Shared Medication History: A Retrospective Study Using the Japanese National Claims Database

While the coronavirus disease 2019 (COVID-19) pandemic has impacted medication adherence and consultation patterns, its effects on the medical practice and dispensary separation system of Japan remain unclear. Thus, the utilization of the medication record handbook (MRH) in both medical and dental areas remains uncertain. This study uses the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB); we analyzed the separation of medication prescription and dispensing in both medicine and dentistry, as well as estimated how much drug information is shared by utilizing a patient-carried MRH. The external prescription (EP) rate was used as the main indicator. We then analyzed the MRH utilization rate during outpatient medication guidance. During the pandemic, there was no distinctive change in the rate of EPs in both medicine and dentistry. Furthermore, an analysis between EPs, medical internal prescriptions (IPs), and dental IPs relative to the MRH utilization rate revealed significant correlations between EPs and medical IPs as well as medical and dental IPs. Conversely, no significant correlation was found between EPs and dental IPs. Therefore, our results suggest that active MRH implementation within healthcare facilities may lead to an increase in its utilization in dentistry.

Dental abnormalities in rare genetic bone diseases: Literature review

Currently, over 500 rare genetic bone disorders are identified. These diseases are often accompanied by dental abnormalities, which are sometimes the first clue for an early diagnosis. However, not many dentists are sufficiently familiar with phenotypic abnormalities and treatment approaches when they encounter patients with rare diseases. Such patients often need dental treatment but have difficulties in finding a dentist who can treat them appropriately. Herein we focus on major dental phenotypes and summarize their potential causes and mechanisms, if known. We discuss representative diseases, dental treatments, and their effect on the oral health of patients and on oral health-related quality of life. This review can serve as a starting point for dentists to contribute to early diagnosis and further investigate the best treatment options for patients with rare disorders, with the goal of optimizing treatment outcomes.

Methodological guidance for the use of real-world data to measure exposure and utilization patterns of osteoporosis medications

Observational studies of osteoporosis medications can provide critical real-world evidence (RWE) that fills knowledge gaps left by clinical trials. However, careful consideration of study design is needed to yield reliable estimates of association. In particular, obtaining valid measurements of exposure to osteoporosis medications from real-world data (RWD) sources is complicated due to different medication classes, formulations, and routes of administration, each with different pharmacology. Extended half-lives of bisphosphonates and extended dosing of denosumab and zoledronic acid require particular attention. In addition, prescribing patterns and medication taking behavior often result in gaps in therapy, switching, and concomitant use of osteoporosis therapies. In this review, we present important considerations and provide specialized guidance for measuring osteoporosis drug exposures in RWD. First, we compare different sources of RWD used for osteoporosis drug studies and provide guidance on identifying osteoporosis medication use in these data sources. Next, we provide an overview of osteoporosis pharmacology and how it can influence decisions on exposure measurement within RWD. Finally, we present considerations for the measurement of osteoporosis medication exposure, adherence, switching, long-term exposures, and drug holidays using RWD. Ultimately, a thorough understanding of the differences in RWD sources and the pharmacology of osteoporosis medications is essential to obtain valid estimates of the relationship between osteoporosis medications and outcomes, such as fractures, but also to improve the critical appraisal of published studies.

Etiopathogenesis of medication-related osteonecrosis of the jaws: a review

This study compiles the main hypotheses involved in the etiopathogenesis of medication-related osteonecrosis of the jaw (MRONJ). A narrative review of the literature was performed. The etiopathogenesis of MRONJ is multifactorial and not fully understood. The main hypothesis considers the disturbance of bone turnover caused by anti-resorptive drugs. Bisphosphonates and denosumab inhibit osteoclast activity through different action mechanisms, accumulating bone microfracture. Other hypotheses also consider oral infection and inflammation, the antiangiogenic effect and soft tissue toxicity of bisphosphonates, and the inhibition of lymphangiogenesis. Knowledge of the current theories for MRONJ is necessary to define future studies and protocols to minimize the incidence of this severe condition.

Medication-related osteonecrosis of the jaw (MRONJ): a review of pathogenesis hypothesis and therapy strategies

Medication-related osteonecrosis of the jaw (MRONJ), a severe side effect caused by antiresorptive antiangiogenic medication, particularly bisphosphonates (BPs), has become a challenging disease with serious and profound effects on the physical and mental health of patients. Although it occurs with high frequency and is harmful, the exact mechanism of MRONJ remains unknown, and systematic and targeted approaches are still lacking. Maxillofacial surgeons focus on the etiology of osteonecrosis in the mandible and maxilla as well as the appropriate oral interventions for high-risk patients. Adequate nursing care and pharmacotherapy management are also crucial. This review provides a current overview of the clinicopathologic feature and research of MRONJ caused by BPs, with an emphasis on the potential mechanisms and current therapy and prevention strategies of the disease. We are of the opinion that an in-depth comprehension of the mechanisms underlying MRONJ will facilitate the development of more precise and efficacious therapeutic approaches, resulting in enhanced clinical outcomes for patients.

Rodents as an animal model for studying tooth extraction-related medication-related osteonecrosis of the jaw: assessment of outcomes

OBJECTIVE

To assess the outcomes of several rodent animal models for studying tooth extraction-related medication-related osteonecrosis of the jaw (MRONJ).

DESIGN

After a search of the databases, 2004 articles were located, and 118 corroborated the inclusion factors (in vivo studies in rodents evaluating tooth extraction as a risk factor for the development of MRONJ).

RESULTS

Numerous studies attempting to establish an optimal protocol to induce MRONJ were found. Zoledronic acid (ZA) was the most used drug, followed by alendronate (ALN). Even when ZA did not lead to the development of MRONJ, its effect compromised the homeostasis of the bone and soft tissue. The association of other risk factors (dexamethasone, diabetes, and tooth-related inflammatory dental disease) besides tooth extraction also played a role in the development of MRONJ. In addition, studies demonstrated a relationship between cumulative dose and MRONJ.

CONCLUSIONS

Both ZA and ALN can lead to MRONJ in rodents when equivalent human doses (in osteoporosis or cancer treatment) are used. Local oral risk factors and tooth-related inflammatory dental disease increase the incidence of MRONJ in a tooth extraction-related rodent model.

Investigation of clindamycin concentrations in human plasma and jawbone tissue in patients with osteonecrosis of the jaw: A prospective trial

The aim of this study was to investigate the jawbone concentration of clindamycin (CLI) in patients with an osteonecrosis of the jaw (ONJ). Patients with medication-related ONJ (MRONJ) and osteoradionecrosis (ORN) with an antibiotic treatment with CLI were included. Plasma, vital and necrotic bone samples were collected. Plasma and jawbone samples were analyzed by liquid chromatography-tandem mass spectrometry. Patients with MRONJ exhibited a mean plasma CLI concentration of 9.6 μg/mL (SD ± 3.6 μg/mL) and mean concentrations of 2.3 μg/g CLI (SD ± 1.4 μg/g) and 2.1 μg/g CLI (SD ± 2.4 μg/g) in vital and necrotic bone samples, without statistical significance (p = 0.79). In patients with ORN, mean concentration in plasma was 12.0 μg/mL (SD ± 2.6 μg/mL), in vital bone 2.1 μg/g (SD ± 1.5 μg/g), and in necrotic bone 1.7 μg/g (SD ± 1.2 μg/g). Vital and necrotic bone concentrations did not differ significantly (p = 0.88). The results demonstrate that CLI concentrations are considerably lower than in plasma, but sufficient for most bacteria present in ONJ. Within the limitations of the study, it seems that CLI is a relevant alternative to other antibiotics in the treatment of ONJ because it reaches adequate concentrations in jawbone.

Risk Factors for Infection Recurrence After Surgical Resection of Advanced Stage Osteonecrosis of the Mandible

BACKGROUND

Advanced stage osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ) are challenging disease entities requiring multimodal therapy including surgical resection. However, risk factors associated with infection recurrence are poorly understood.

PURPOSE

The purpose of this study was to identify risk factors associated with infection recurrence following resection of advanced stage ORN or MRONJ of the mandible.

STUDY DESIGN, SETTING, SAMPLE

This was a retrospective cohort study including patients who underwent segmental mandibulectomy for management of ORN or MRONJ between 2016 and 2021 at the authors' institution. Subjects who did not have margin viability data were excluded.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

The primary predictor variable was viability of resection margins on histopathologic analysis (viable or nonviable). Secondarily, other risk factors categorized as demographic (age, sex, race), medical (comorbidities), and perioperative (reconstructive modality, antibiotic duration, microbiological growth) were evaluated.

MAIN OUTCOME VARIABLE

The primary outcome variable was time to infection recurrence defined as time from surgical resection to clinical diagnosis of a fistula tract, abscess, or persistent inflammatory symptoms necessitating surgical intervention.

COVARIATES

Not applicable.

ANALYSES

Descriptive and bivariate statistics were used to identify associations between risk factors and time to infection recurrence. A significance level of P ≤ .05 was considered significant.

RESULTS

The cohort consisted of 57 subjects with a mean age of 63.3 ± 10.0 years (71.9% Male, 75.4% White) treated for ORN (47.4%) or MRONJ (52.6%). A total of 19/57 (33%) subjects developed a recurrence of infection with 1 and 2 year survival of 75.8 and 66.2%, respectively. Nonviable resection margins were associated with earlier time to infection recurrence (P ≤ .001, hazard ratio (HR) = 11.9, 95% confidence interval (CI) = 3.84 to 36.7) as was younger age (P = .005, HR = 0.921, 95% CI = 0.869 to 0.976) and atypical pathogen growth on culture (P = .002, HR = 8.58, 95% CI = 2.24 to 32.8).

CONCLUSIONS AND RELEVANCE

Histopathologic margin viability was associated with earlier time to infection recurrence following resection of advanced stage ORN or MRONJ of the mandible. Additional studies are needed to identify interventions that may improve outcomes in this demographic.

Successful radiofrequency thermocoagulation of the mandibular nerve for intractable pain associated with medication-related osteonecrosis of the jaw: a case report

BACKGROUND

Bisphosphonates may cause serious adverse events, including osteonecrosis of the jaw. This article describes a case of successful application of radiofrequency thermocoagulation for pain caused by osteonecrosis of the jaw.

CASE PRESENTATION

An 86-year-old woman who had received alendronate sodium hydrate for osteoporosis was diagnosed with osteonecrosis of the right mandible after dental treatment. Despite repeated conservative and debridement treatments, the patient could not eat due to intractable pain; accordingly, her condition was debilitated. The patient was referred to our pain management clinic for radiofrequency thermocoagulation of the right mandibular nerve. Immediately after the procedure, her pain drastically improved and she could eat; moreover, the pain has not recurred for 3 years.

CONCLUSION

Our findings demonstrate that minimally invasive radiofrequency thermocoagulation may have long-term effects in patients with chronic pain caused by osteonecrosis of the jaw that is refractory to conservative treatment.

Can medication-related osteonecrosis of the jaw be attributed to specific microorganisms through oral microbiota analyses? A preliminary study

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) can cause significant pain and loss of aesthetics and function if not treated properly. However, diagnosis still relies on detailed intraoral examinations and imaging. Prognosis varies even among patients with similar stages or conditions of MRONJ, emphasizing the need for a deeper understanding of its complex mechanisms. Thus, this study aimed to identify the oral microbiota of patients with MRONJ.

METHODS

This single-center prospective cohort study included patients with confirmed MRONJ who visited the Department of Oral and Maxillofacial Surgery at Yonsei University Dental Hospital between 2021 and 2022. Oral swab samples were collected from the affected and unaffected sides of each patient. The composition and enumeration of the microbial communities were analyzed, and the diversity was compared to verify ecological changes in the groups using a next-generation sequencing-based 16S metagenomic analysis. A statistical analysis was performed using Wilcoxon signed-rank test with SPSS version 22, and values of P less than 0.05 were considered statistically significant.

RESULTS

The final study sample included 12 patients. The mean age was 82.67 ± 5.73 (range, 72-90) years. Changes in microbial composition were observed at different taxonomic levels (phylum, genus, and species). The identified microorganisms were commonly associated with periodontitis, gingival disease, and endodontic infection, suggesting a multifactorial etiology of MRONJ.

CONCLUSIONS

Although this study is based on a small number of cases, it shows that MRONJ is not caused by a specific microorganism but can rather be caused by a variety of factors. By addressing these findings in large-scale studies, the significance of oral microbiome in pathogenesis can be further elucidated and can facilitate the development of effective therapeutic interventions for patients with MRONJ.

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.

Bisphosphonate therapy in the management of diffuse sclerosing osteomyelitis of the mandible: a systematic review and narrative synthesis

Background

Diffuse sclerosing osteomyelitis (DSO) affecting the mandible is an uncommon condition characterised by recurrent pain and functional disturbances. Traditional treatments involving antibiotics, steroids, and analgesics have generally yielded unsatisfactory results. Numerous articles have proposed the utilisation of bisphosphonate therapy as an alternative approach to achieve sustained symptom relief. This study aims to consolidate the available evidence on the effectiveness of bisphosphonate therapy in managing DSO.

Methods

A systematic review protocol was registered with PROSPERO and reported in accordance with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses. Comprehensive electronic search strategies were devised, and studies were screened based on predefined inclusion and exclusion criteria.

Results

Ten articles met the eligibility criteria, encompassing a total of 135 patients diagnosed with DSO who received bisphosphonate treatment. All included studies consistently reported a reduction in pain levels and swelling, along with a decrease in the cumulative use of analgesics. The majority of patients reported long-lasting symptom improvement with bisphosphonate therapy. Notably, four studies documented improvements in maximal mouth opening, with one study reporting a mean increase of 9.6mm. Furthermore, six studies observed improvements in panoramic radiographs and cone beam computed tomography scans, with one publication describing two patients exhibiting near-normal bone architecture. Importantly, all studies reported the absence of long-term complications.

Conclusions

Bisphosphonate therapy emerges as a promising treatment modality for DSO, exhibiting efficacy in symptom alleviation and radiological enhancement while conferring lasting benefits. Nevertheless, further prospective studies are warranted to refine treatment protocols and substantiate these findings.

[Emergencies in cancer therapy: surgical indications under systemic therapy]

Emergency surgery due to side-effects of cancer therapy in patients with metastatic disease of the genitourinary tract is rare. Nevertheless, there are a number of emergencies that require rapid intervention and should be recognized by every uro-oncologist. The following review will work out important side-effects requiring surgical treatment, highlighting the main symptoms and the initial management.

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.

Gut microbial community and fecal metabolomic signatures in different types of osteoporosis animal models

BACKGROUND

The gut microbiota (GM) constitutes a critical factor in the maintenance of physiological homeostasis. Numerous studies have empirically demonstrated that the GM is closely associated with the onset and progression of osteoporosis (OP). Nevertheless, the characteristics of the GM and its metabolites related to different forms of OP are poorly understood. In the present study, we examined the changes in the GM and its metabolites associated with various types of OP as well as the correlations among them.

METHODS

We simultaneously established rat postmenopausal, disuse-induced, and glucocorticoid-induced OP models. We used micro-CT and histological analyses to observe bone microstructure, three-point bending tests to measure bone strength, and enzyme-linked immunosorbent assay (ELISA) to evaluate the biochemical markers of bone turnover in the three rat OP models and the control. We applied 16s rDNA to analyze GM abundance and employed untargeted metabolomics to identify fecal metabolites in all four treatment groups. We implemented multi-omics methods to explore the relationships among OP, the GM, and its metabolites.

RESULTS

The 16S rDNA sequencing revealed that both the abundance and alterations of the GM significantly differed among the OP groups. In the postmenopausal OP model, the bacterial genera g__Bacteroidetes_unclassified, g__Firmicutes_unclassified, and g__Eggerthella had changed. In the disuse-induced and glucocorticoid-induced OP models, g__Akkermansia and g__Rothia changed, respectively. Untargeted metabolomics disclosed that the GM-derived metabolites significantly differed among the OP types. However, a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that it was mainly metabolites implicated in lipid and amino acid metabolism that were altered in all cases. An association analysis indicated that the histidine metabolism intermediate 4-(β-acetylaminoethyl) imidazole was common to all OP forms and was strongly correlated with all bone metabolism-related bacterial genera. Hence, 4-(β-acetylaminoethyl) imidazole might play a vital role in OP onset and progression.

CONCLUSIONS

The present work revealed the alterations in the GM and its metabolites that are associated with OP. It also disclosed the changes in the GM that are characteristic of each type of OP. Future research should endeavor to determine the causal and regulatory effects of the GM and the metabolites typical of each form of OP.

Physicians' awareness of medication-related osteonecrosis of the jaw in patients with osteoporosis

A serious adverse effect of antiresorptive drugs, which are widely used to treat osteoporosis, is medication-related osteonecrosis of the jaw (MRONJ). Physicians can reduce the risk of MRONJ by educating patients and emphasizing the importance of good oral health. However, limited information is available regarding physicians' awareness and clinical practices associated with MRONJ. Hence, this study aimed to examine physicians' awareness related to MRONJ and associated clinical practices. This study was a cross-sectional study conducted from December 2022 to February 2023. An online self-administered questionnaire was sent to physicians in Thailand who prescribed antiresorptive drugs for osteoporosis. Most respondents agreed that antiresorptive drugs might cause MRONJ (92.3%), poor oral health increased the risk of MRONJ (84%), and MRONJ is an important consideration in patients with osteoporosis (85%). Of the respondents, 48.1% and 15.5% always referred patients to dentists before and during antiresorptive therapy, respectively. Approximately 60% of physicians informed patients of the MRONJ risk before prescribing antiresorptive drugs, and 30% inquired about patients' oral symptoms at the follow-up visit. Overall, 44% of physicians advised patients to receive oral health care; the most common reason for not advising this was that respondents did not consider themselves to be adequately knowledgeable to detect oral health problems. These findings indicate that while most physicians who prescribed antiresorptive drugs for osteoporosis were aware of and considered MRONJ in their practice, several took insufficient action to prevent it. This highlights the need to emphasize clinical practice guidelines and collaboration between physicians and dentists.

Sequential Therapy for the Long-Term Treatment of Postmenopausal Osteoporosis

Osteoporosis is a chronic condition characterized by decreased bone mass, loss of skeletal integrity, and increased susceptibility to fracture. Drugs used to treat osteoporosis can be classified as those that block bone resorption (antiresorptive), stimulate bone formation (anabolic), or do both. While all currently approved medications reduce the risk of fragility fractures in high-risk populations, they are generally unable to fully restore bone strength in most patients with established disease. Thus, the majority of patients require disease management over many years. Unfortunately, the continuous use of a single drug has limitations, both in terms of efficacy and safety, and so sequential therapy is commonly required. Given the expanding list of pharmacological agents currently available, careful consideration needs to be given as to which drugs to use and in what sequence. This review will evaluate the differential effects of antiresorptive, bone-forming, and dual-acting drugs when used in specific sequences and will explore the current evidence favoring the initial use of bone-forming/dual-acting drugs followed by antiresorptive medications. This review will also examine the notion that long-term treatment with an antiresorptive drug may diminish the efficacy of subsequent treatment with a bone-forming/dual-acting drug. Finally, this review will explore the current evidence pertaining to the specific issue of how to best prevent the clinical ramifications of denosumab cessation.

Bone-Targeting Peptide and RNF146 Modified Apoptotic Extracellular Vesicles Alleviate Osteoporosis

Background

Osteoporosis is a highly prevalent disease that causes fractures and loss of motor function. Current drugs targeted for osteoporosis often have inevitable side effects. Bone marrow mesenchymal stem cell (BMSCs)-derived apoptotic extracellular vesicles (ApoEVs) are nanoscale extracellular vesicles, which has been shown to promote bone regeneration with low immunogenicity and high biological compatibility. However, natural ApoEVs cannot inherently target bones, and are often eliminated by macrophages in the liver and spleen. Thus, our study aimed to reconstruct ApoEVs to enhance their bone-targeting capabilities and bone-promoting function and to provide a new method for osteoporosis treatment.

Methods

We conjugated a bone-targeting peptide, (Asp-Ser-Ser)6 ((DSS)6), onto the surface of ApoEVs using standard carbodiimide chemistry with DSPE-PEG-COOH serving as the linker. The bone-targeting ability of (DSS)6-ApoEVs was determined using an in vivo imaging system and confocal laser scanning microscopy (CLSM). We then loaded ubiquitin ligase RING finger protein146 (RNF146) into BMSCs via adenovirus transduction to obtain functional ApoEVs. The bone-promoting abilities of (DSS)6-ApoEVs and (DSS)6-ApoEVsRNF146 were measured in vitro and in vivo.

Results

Our study successfully synthesized bone-targeting and gained functional (DSS)6-ApoEVsRNF146 and found that engineered ApoEVs could promote osteogenesis in vitro and exert significant bone-targeting and osteogenesis-promoting effects to alleviate osteoporosis in a mouse model.

Conclusion

To promote the bone-targeting ability of natural ApoEVs, we successfully synthesized engineered ApoEVs, (DSS)6-ApoEVsRNF146 and found that they could significantly promote osteogenesis and alleviate osteoporosis compared with natural ApoEVs, which holds great promise for the treatment of osteoporosis.

Bioinformatic analysis of related immune cell infiltration and key genes in the progression of osteonecrosis of the femoral head

Objective

Osteonecrosis of the femoral head (ONFH) is a common orthopedic condition that will prompt joint dysfunction, significantly impacting patients' quality of life. However, the specific pathogenic mechanisms underlying this disease remain elusive. The objective of this study is to examine the differentially expressed messenger RNAs (DE mRNAs) and key genes linked to ONFH, concurrently investigating the immune cell infiltration features in ONFH patients through the application of the CIBERSORT algorithm.

Methods

Microarray was applied to scrutinize mRNA expression profiles in both ONFH patients and healthy controls, with data integration sourced from the GEO database. DE mRNAs were screened using the Limma method. The biological functions of DE mRNAs were explored through the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, Gene Ontology (GO) functional analysis, and Gene Set Enrichment Analysis (GSEA). Additionally, support vector machine-recursive feature elimination (SVM-RFE) and the least absolute shrinkage and selection operator (LASSO) were employed to discern diagnostic biomarkers associated with the disease. Receiver operating characteristic (ROC) analysis was utilized to assess the statistical performance of the feature genes. The validation of key genes was performed using qRT-PCR in bone tissues obtained from ONFH patients and healthy controls. Osteogenic differentiation of BMSC was then performed and detected by alkaline phosphatase staining (ALP) and qRT-PCR to verify the correlation between key genes and osteogenic differentiation. Finally, immune cell infiltration analysis was executed to evaluate immune cell dysregulation in ONFH, concurrently exploring the correlation between the infiltration of immune cells and key genes.

Results

After consolidating the datasets, the Limma method revealed 107 DEGs, comprising 76 downregulated and 31 upregulated genes. Enrichment analysis revealed close associations of these DE mRNAs with functions such as cell migration, osteoblast differentiation, cartilage development and extracellular region. Machine learning algorithms further identified APOD, FBXO43 and LRP12 as key genes. ROC curves demonstrated the high diagnostic efficacy of these genes. The results of qRT-PCR showed that the expression levels of key genes were consistent with those of microarray analysis. In addition, the results of in vitro experiments showed that APOD was closely related to osteogenic differentiation of BMSC. Immune infiltration analysis suggested a close correlation between ONFH and imbalances in levels of Neutrophils, Monocytes, Macrophages M2, Dendritic cells activated and Dendritic cells resting.

Conclusion

APOD is closely related to osteogenic differentiation of BMSCs and can be used as a diagnostic marker of ONFH. Immune cell infiltration significantly differs between controls and ONFH patients.

No increased risk of osteonecrosis of the jaw in osteoporotic patients with dental implants: a nationwide cohort study

OBJECTIVES

The occurrence of implant-associated osteonecrosis of the jaw (ONJ) has been reported in osteoporotic patients, particularly in association with bisphosphonate therapy. This study aimed to investigate the risk of implant surgery and implant presence for ONJ occurrence in osteoporotic patients longitudinally.

METHODS

Based on Korean National Health Information Database, subjects over the age of 65 who were diagnosed with osteoporosis between July 2014 and December 2016 were included. The implant group included subjects who had undergone dental implant surgery between January 2017 and December 2017, while the control group included those who had no history of dental implants. The primary outcome was the occurrence of ONJ, and the date of final follow-up was December 2020.

RESULTS

A total of 332,728 subjects with osteoporosis were included in the analysis: 83,182 in the implant group and 249,546 in the control group. The risk of ONJ among those who had undergone implant surgery (risk of implant surgery-associated ONJ) was not higher than that among those without implant surgery. The risk of ONJ among those with implants (risk of implant presence-associated ONJ) was lower than that among those without implants. Even in subjects with a history of bisphosphonates, steroids, periodontitis, or tooth extraction, those who had undergone implant surgery or had implants did not have a higher ONJ risk than those who had not undergone surgery or did not have implants; rather, they showed a lower risk.

CONCLUSIONS

The results may suggest that dental implants are not associated with an increased risk of ONJ. A further study on whether dental implants are associated with lower ONJ risk is needed.

CLINICAL RELEVANCE

Dental implants did not increase the risk of ONJ development in osteoporotic patients, even with a history of bisphosphonates. This may suggest that the risk profiles for ONJ occurrence between selective insertion of dental implants and other dentoalveolar surgery associated with infectious conditions are different.

Hyperbaric oxygen therapy as an adjunct treatment of periodontitis, MRONJ, and ONJ: a systematic literature review

OBJECTIVE

To review the available prospective literature on hyperbaric oxygen (HBO) therapy for periodontal conditions.

MATERIALS AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies on adult patients who underwent hyperbaric oxygen therapy for periodontal treatments. A systematic literature search was conducted in PubMed, Cochrane, and Dentistry Oral Sciences Source databases.

RESULTS

Fourteen articles were included in the final literature review, of which five were RCTs and 11 were prospective clinical studies. Four studies discussed HBO as an adjunct to nonsurgical treatment of periodontitis, eight reported on HBO and osteoradionecrosis, and one examined HBO in bisphosphonate-related necrosis of the jaws.

CONCLUSIONS

HBO has shown superior efficacy compared to antibiotics as a prophylactic measure in preventing osteoradionecrosis (ORN) in patients with a history of high mandibular irradiation. Clinicians should consider referring such patients for HBO therapy before and after tooth extractions. However, for the surgical excision of existing ORN lesions, HBO therapy does not yield significant benefits but does not negatively impact outcomes either. Regarding the treatment of periodontitis patients, the variability among studies prevents definitive conclusions. HBO therapy as an adjunct to SRP in periodontitis treatment produces mixed results.

CLINICAL RELEVANCE

This study's clinical relevance lies in its exploration of the potential benefits of HBO for periodontal conditions. Also, it provides clinicians with insights into when and how to integrate HBO therapy into their treatment approaches, particularly for patients with a history of irradiation and those undergoing complex dental procedures.

Assessing dental surgeons' understanding of bisphosphonates: Implications for patient health in oral surgery

Objectives

This study aimed to analyze the knowledge of dental surgeons concerning the pharmacological effects of bisphosphonates (BP) and their impact on the health of patients undergoing oral surgery treatment.

Materials and methods

A quantitative study was conducted with professionals in the Cariri region of Ceará, Brazil. The data were collected using a semi-structured questionnaire to interview the dental surgeons who met the inclusion criteria. The data were analyzed by Chi-square and Fischer's Exact tests using the SPSS program version 22.0.

Results

The results indicated that most interviewed subjects have no experience with the dental treatment of individuals under treatment with bisphosphonates. When a sample of the medication was presented, a significant number of the participants (65.3%) did not recognize the drug. Among those who recognized it, 66.5% did not know how to treat bisphosphonate-using patients in the clinical routine. However, 95.1% of the professionals who recognized the need to discontinue these drugs admitted contacting the prescriber to establish the best dental conduct. Our results also showed that recently graduated professionals better understood the need to stop BP use before invasive treatment, although they did not know the protocol.

Conclusion

In conclusion, a better knowledge of the pharmacological effects of BP is crucial for conducting adequate anamnesis, requesting additional tests, and performing medical monitoring, which has a significant impact on the clinical practice of dental surgeons.

No evidence of genetic causality between diabetes and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis

OBJECTIVE

This study aimed to examine whether diabetes mellitus is causally associated with osteonecrosis.

METHOD

Using publicly accessible genome-wide association study statistics, a bidirectional two-sample Mendelian randomization analysis was carried out. In order to determine whether diabetes has a causal effect on osteonecrosis and whether osteonecrosis has a causal effect on diabetes, we extracted six date on diabetes in Europeans from IEU OpenGWAS and GWAS Catalogue and osteonecrosis in Europeans from FinnGen. We then evaluated the data using inverse variance weighting, MR-Egger regression, weighted median, weighted mode, and simple mode. The results' stability and dependability were then evaluated using sensitivity analysis and heterogeneity analysis. Finally, meta-analysis is used to further confirm if there is a relationship between diabetes and osteonecrosis.

RESULTS

When diabetes was used as an exposure factor, MR-Egger regression showed that directional fold product was unlikely to bias the results. Cochran's Q test showed only minor heterogeneity in a few data sets. Multidirectional tests Egger-intercept, MR-PRESSO and funnel plots for most data did not show multidirectional and asymmetry at the gene level. Most of the IVW results showed no causal relationship between diabetes mellitus and osteonecrosis. The results of meta-analysis of IVW methods further confirmed the absence of a causal relationship. Inverse MR analysis also showed no causal relationship between osteonecrosis and diabetes.

CONCLUSION

Results of bidirectional MR analysis show no evidence of causal relationship between diabetes and osteonecrosis.

Zoledronate and osteonecrosis of the jaw in osteoporosis: incidence and risk factors. Analysis of the French Pharmacovigilance Database

INTRODUCTION

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) have been characterized with the use of oral bisphosphonates in osteoporosis and zoledronate in oncology. Uncertainties remain, though, with the occurrence of BRONJ related to the use of zoledronate in osteoporosis.

OBJECTIVES

We aimed to estimate the incidence and characterize the risk factors of zoledronate-associated BRONJ in osteoporosis as compared with oral bisphosphonates in real life setting.

METHODS

Cases of BRONJ associated with zoledronate, alendronate or risedronate were extracted from the French pharmacovigilance database up to 2020. The incidence of BRONJ was estimated as their respective numbers related to cases of BRONJ in patients treated with bisphosphonates for osteoporosis, over the same period, according to the Medic'AM database.

RESULTS

Between 2011 and 2020, BRONJ incidence with zoledronate was 9.6/100,000 patient-year (PY), significantly higher than with alendronate (5.1/100,000 PY, P<0.001), and risedronate (2.0/100,000 PY, P<0.001). The number of patients treated with bisphosphonates has steadily decreased by 44.5% over 10 years. Meanwhile, the incidence of BRONJ decreased (5.8/100,000 PY in 2011; 1.5/100,000 in 2020), although a rebound was observed in 2018, including 47.6% of BRONJ following denosumab. Apart from classical risk factors, recent dental cares stood out in more than 40% of BRONJ, and zoledronate had a shorter exposure time than oral bisphosphonates.

CONCLUSIONS

In a real-life setting, our data confirm that zoledronate-associated BRONJ in osteoporosis is scarce, seeming slightly more common compared with oral bisphosphonates. We also raise awareness of dental care guidelines and greater vigilance when using bisphosphonates in patients with previous exposure to denosumab.

Bone-Targeted Therapy Regimen and Skeletal-Related Events in Patients Surviving Longer Than 2 Years With Metastatic Breast Cancer and Bone Metastasis

BACKGROUND

Bone-targeted therapy (BTT) including zoledronic acid (ZA) and denosumab decreases the risk of skeletal-related events (SREs) in patients with metastatic breast cancer (MBC) and bone metastasis. The impacts from prolonged BTT on SREs and BTT-associated harms are unknown and are becoming important to understand as these patients survive for longer periods.

METHODS AND MATERIALS

We conducted a retrospective study of 224 patients with MBC and bone metastasis who survived for more than 2 years after diagnosis and received treatment at our institution between 2016 and 2021. We defined 3 BTT patterns: (1) ZA only, (2) denosumab only, (3) both ZA and denosumab. The association between these BTT patterns and SREs and harms was assessed using Fisher exact test and logistic regression.

RESULTS

Rates of SREs overall were 21.2% of patients given ZA only, 8.8% of those given denosumab only, and 20% of those given both, without statistically significant differences (p = .32). However, those treated with denosumab only had significantly fewer compression fractures (0.7%) (p = .02). BTT-associated harm was observed in 5.8% of the ZA-only group, 11.7% of the denosumab-only group, and 14.3% of the group given both, without statistically significant differences (p = .37).

CONCLUSION

Oncologists may have increased flexibility regarding the frequency of administration of BTT along with their choice of agent. Our study showed no significant difference in the prevention of overall SRE or development of BTT-associated harms between the BTT regimens evaluated.

Depletion of macrophages deteriorates bisphosphonate-related osteonecrosis of the jaw-like lesions in mice

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a potentially intractable disease with no definitive pathophysiology and no treatment and prevention strategies. This study aimed to investigate whether time-selective depletion of macrophages worsens BRONJ-like lesions in mice. A murine model of high-prevalence BRONJ-like lesions in combination with zoledronate/chemotherapeutic drug administration and tooth extraction was created according to the methods of our previous studies. Daily intra-oral submucosal administration of clodronate-loaded liposomes, which temporarily depletes systemic macrophages, was performed immediately after tooth extraction. Spleens, femora, tibiae, and maxillae were dissected 2 weeks after extraction to evaluate BRONJ-like lesions and systemic conditions by micro-computed tomography analysis, histomorphometric and immunofluorescent analyses, and serum chemistry with ELISA. Depletion of macrophages significantly decreased the numbers of local and systemic macrophages and osteoclasts on the bone surface, which markedly worsened osseous healing, with increased necrotic bone and empty lacunae in the existing alveolar bone and newly formed bone in the extraction sockets, and soft tissue healing, with decreased collagen production and increased infiltration of polymorphonuclear cells. Interestingly, the depletion of macrophages significantly shifted macrophage polarization to M1 macrophages through an increase in F4/80+CD38+ M1 macrophages and a decrease in F4/80+CD163+ M2 macrophages, with decreases in the total number of F4/80+ macrophages. These data demonstrated that severe inhibition of osteoclasts in bone tissue and polarization shifting of macrophages in soft tissue are essential factors associated with BRONJ.

Long-term consequences of osteoporosis therapy with bisphosphonates

Bisphosphonates (BPs) are medications widely used in clinical practice to treat osteoporosis and reduce fragility fractures. Its beneficial effects on bone tissue have been consolidated in the literature for the last decades. They have a high affinity for bone hydroxyapatite crystals, and most bisphosphonates remain on the bone surface for a long period of time. Benefits of long-term use of BPs: Large and important trials (Fracture Intervention Trial Long-term Extension and Health Outcomes and Reduced Incidence with Zoledronic acid Once Yearly-Pivotal Fracture Trial) with extended use of alendronate (up to 10 years) and zoledronate (up to 6 years) evidenced significant gain of bone mineral density (BMD) and vertebral fracture risk reduction. Risks of long-term use of BPs: The extended use of antiresorptive therapy has drawn attention to two extremely rare, although severe, adverse events. That is, atypical femoral fracture and medication-related osteonecrosis of the jaw are more common in patients with high cumulative doses and longer duration of therapy. BPs have demonstrated safety and effectiveness throughout the years and evidenced increased BMD and reduced fracture risks, resulting in reduced morbimortality, and improved quality of life. These benefits overweight the risks of rare adverse events.

Indication and adverse event profiles of denosumab and zoledronic acid: based on U.S. FDA adverse event reporting system (FAERS)

Objective: To investigate adverse events (AEs) associated with denosumab (Dmab) and zoledronic acid (ZA), compare their association strengths, and explore potential applications to provide clinical reference. Methods: We collected data from FAERS from January 2004 to November 2022 and mined AE signals for Dmab and ZA using ROR values. We compared signal intensity for same AEs and investigated off-label use. We also examined their AEs in adjuvant therapy for breast and prostate cancer. Results: 154,735 reports of primary suspect drugs were analyzed in the FAERS database (Dmab: 117,857; ZA: 36,878). Dmab and ZA had 333 and 1,379 AE signals, with 189 overlaps. The AEs of Dmab included death (ROR:3.478), osteonecrosis of jaw (ROR:53.025), back pain (ROR:2.432), tooth disorder (ROR:16.18), bone pain (ROR:6.523). For ZA, the AEs included osteonecrosis (ROR:104.866), death (ROR: 3.645), pain (ROR:3.963), osteonecrosis of jaw (ROR: 91.744), tooth extraction (ROR: 142.143). Among overlap signals, Dmab showed higher strength in exostosis of the jaw (ROR: 182.66 vs. 5.769), atypical fractures (ROR: 55.589 vs. 9.123), and atypical femur fractures (ROR:49.824 vs. 4.968). And ZA exhibited stronger associations in abscess jaw (ROR: 84.119 vs. 11.12), gingival ulceration (ROR: 74.125 vs. 4.827), increased bone formation (ROR: 69.344 vs. 3.218). Additionally, we identified 528 off-label uses for Dmab and 206 for ZA, with Dmab mainly used in prostate cancer (1.04%), breast cancer (1.03%), and arthritis (0.42%), while ZA in breast cancer (3.21%), prostate cancer (2.48%), and neoplasm malignant (0.52%). For Dmab in breast cancer treatment, AEs included death (11.6%), disease progression (3.3%), and neutropenia (2.7%), while for ZA included death (19.8%), emotional disorder (12.9%), osteomyelitis (11.7%). For prostate cancer treatment, Dmab`s AEs were death (8.9%), prostate cancer metastatic (1.6%), renal impairment (1.7%), while ZA`s included death (34.4%), general physical health deterioration (19.9%), and hemoglobin decreased (18.9%). Conclusion: Our analysis of FAERS database provided postmarketing surveillance data and revealed different strengths of reported AE signals between Dmab and ZA in some of their common AEs. It's also worth noting that both drugs have potential off-label applications, which could introduce new AEs. This highlights the necessity for safety monitoring when using Dmab and ZA off-label.

Denosumab for giant cell tumors of bone from 2010 to 2022: a bibliometric analysis

Giant cell tumors of the bone (GCTB) are considered moderately malignant bone tumors. Denosumab, as a neoadjuvant therapy, provides new possibilities for treating GCTB. However, even after multiple studies and long-term clinical trials, there are limitations in the treatment process. Research data and Medical Subject Headings terms related to denosumab and GCTB were collected from January 2010 to October 2022 using the Web of Science and MeSH ( https://meshb.nlm.nih.gov ) browsers. These data were imported into CiteSpace and VOSviewer softwares for bibliometric analysis. Overall, 445 publications on denosumab and GCTB were identified. Over the last 12 years, the growth rate of the total number of publications has remained relatively stable. The USA published the highest number of articles (83) and had the highest centrality (0.42). Amgen Inc. and Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) First Ortoped Rizzoli were identified as the most influential institutions. Many authors have made outstanding contributions to this field. Lancet Oncology had the highest journal impact factor (54.433). Local recurrence and drug dosage are current research hotspots, and future development trends will mainly focus on prognostic markers of GCTB and the development of new therapies. Further research is required to analyze denosumab's safety and efficacy and understand its local recurrence of GCTB, to identify the optimal dose. Future progress in this field will likely focus on exploring new diagnostic and recurrence markers to monitor disease progression and examine new therapeutic targets and treatment strategies.

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.

5'-Methylthioadenosine strongly suppresses RANKL-induced osteoclast differentiation and function via inhibition of RANK-NFATc1 signalling pathways

Excessive osteoclast-mediated bone resorption is a critical cause of osteoporosis affecting many aging people worldwide. 5'-Methylthioadenosine (MTA) is a natural sulfur-containing nucleoside normally produced in prokaryotes, plants, yeast, and higher eukaryotes via polyamine metabolism. MTA affects various physiological responses particularly the inflammatory pathway in both normal and cancerous cells and modulates the activation of nuclear factor-κB involved in the osteoclastogenesis signalling process. While several studies have reported that natural products possess anti-osteoclastogenesis phenolics and flavonoids, the effect of nucleoside derivatives on osteoclastogenesis remains limited. Therefore, this study aimed to explore the molecular mechanisms by which MTA affects pre-osteoclastic RAW 264.7 cells as a potential alleviation compound for inflammation-mediated bone loss. Osteoclasts were established by incubating RAW264.7 macrophage cells with receptor activator of nuclear factor kappa B ligand (RANKL) and macrophage colony-stimulating factor, the vital cytokines for activation of osteoclast differentiation. Cell viability was measured using MTT assays at 24, 48, and 72 h. The suppressive effect of MTA on RANKL-induced osteoclast differentiation and function was assessed using tartrate-resistant acid phosphatase (TRAP) analysis, qRT-PCR, and pit formation, Western blot, and immunofluorescence assays. MTA showed dose-dependent anti-osteoclastogenic activity by inhibiting TRAP-positive cell and pit formation and reducing essential digestive enzymes, including TRAP, cathepsin K, and matrix metallopeptidase 9. MTA was observed to suppress the osteoclast transduction pathway through (RANKL)-induced nuclear factor kappa-light-chain-enhancer of activated B cells (NFƘB); it attenuated NFƘB-P65 expression and down-regulated cFos proto-oncogene and nuclear factor of activated T cell c1 (NFATc1), the main regulators of osteoclasts. Moreover, the suppression of RANK (the initial receptor triggering several osteoclastogenic transduction pathways) was observed. Thus, this study highlights the potential of MTA as an effective therapeutic compound for restoring bone metabolic disease by inhibiting the RANK-NFATc1 signal pathway.

Medication-related osteonecrosis of the jaw triggered by endodontic failure in oncologic patients

OBJECTIVES

To describe the association between endodontic treatment failure and medication-related osteonecrosis of the jaw (MRONJ) in a cohort of oncologic patients in therapy with antiresorptive and antiangiogenic drugs.

MATERIALS AND METHODS

Patients were selected as affected by MRONJ in absence of the common local risk factors (oral surgical procedures or ill-fitting dentures) but showing failure of previous endodontic treatment performed at least 6 months before the starting of antiresorptive/antiangiogenic therapies. Jaw lesions were all surgically treated and patients underwent a strict clinical and radiological follow-up.

RESULTS

Among 18 patients, who developed 18 MRONJ, the only detectable local risk factor was the presence of teeth with failed endodontic treatment (more precisely, root canal underfilling in eight cases, root canal overfilling in two cases, root perforation in three cases, root fracture in five cases). All patients completely healed after surgical procedure and no recurrence was observed.

CONCLUSIONS

Endodontic treatment failure should be considered a local risk factor for MRONJ development in oncologic patients. For such reason, it is mandatory to carefully evaluate them prior than the beginning of antiresorptive and antiangiogenic drugs administration.

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.

Comparison of the Effectiveness of Conservative and Surgical Treatment of Medication-Related Osteonecrosis of the Jaw: a Systematic Review

Objectives

The objective of this systematic review is to evaluate the current knowledge on the effectiveness of conservative and surgical treatment of medication-related osteonecrosis of the jaw.

Material and Methods

MEDLINE (PubMed), ScienceDirect and Cochrane Library search in combination with hand-search of relevant journals was conducted including human studies published in English between January 2017 and February 2023. Studies assessing treatment strategies for medication-related osteonecrosis of the jaw (MRONJ) were included. Quality and risk-of-bias assessment were evaluated by Joanna Briggs Institute (JBI) Risk of Bias tool.

Results

A total of 4227 articles were screened from which 9 studies (7 cohort studies and 2 randomized controlled trials) met the inclusion criteria and were included in the final data synthesis. Two studies evaluate effectiveness of conservative approaches for treating MRONJ, 5 studies evaluate surgical approaches effectiveness, and 2 studies compare between those approaches. The follow-up period ranged from 6 months to 60 months. According to bias assessment, the mean JDI score of the included studies was > 9 ("low risk of bias"). The stage of the disease, the procedure performed on the patient and the results of the treatment were presented.

Conclusions

Surgical therapy seems to be superior to conservative therapy for the management of adverse stages medication-related osteonecrosis of the jaws, while conservative treatment appears to yield good outcomes at asymptomatic patients with early stages of the disease.

The Capacity of Magnesium to Induce Osteoclast Differentiation Is Greatly Enhanced by the Presence of Zoledronate

Bisphosphonates (BPs) are successfully used to cure a number of diseases characterized by a metabolic reduction in bone density, such as Osteoporosis, or a neoplastic destruction of bone tissue, such as multiple myeloma and bone metastases. These drugs exert their therapeutic effect by causing a systemic osteoclast depletion that, in turn, is responsible for reduced bone resorption. Unfortunately, in addition to their beneficial activity, BPs can also determine a frightening side effect known as osteonecrosis of the jaw (ONJ). It is generally believed that the inability of osteoclasts to dispose of inflamed/necrotic bone represents the main physiopathological aspect of ONJ. In principle, a therapeutic strategy able to elicit a local re-activation of osteoclast production could counteract ONJ and promote the healing of its lesions. Using an experimental model of Vitamin D3-dependent osteoclastogenesis, we have previously demonstrated that Magnesium is a powerful inducer of osteoclast differentiation. Here we show that, surprisingly, this effect is greatly enhanced by the presence of Zoledronate, chosen for our study because it is the most effective and dangerous of the BPs. This finding allows us to hypothesize that Magnesium might play an important role in the topical therapy of ONJ.

Awareness, perceptions and attitudes toward medication-related osteonecrosis of the jaw among physicians who treat osteoporosis

Osteoporosis is the most common indication for antiresorptive drugs (ARDs). Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication of ARDs. Multiple risk factors can increase the risk of MRONJ, one of which is the duration of ARD intake, which is usually prolonged for osteoporosis cases. Prevention of MRONJ relies on collaborative care between treating physicians and dental practitioners. Therefore, knowledge about MRONJ and its prevention strategies is crucial for both teams.

Aim

This study aimed to assess the knowledge and attitudes of physicians toward MRONJ in osteoporosis patients. Another aim was to develop recommendations for the prevention of MRONJ.

Materials and methods

Through an online survey, basic information such as the practice location, training, knowledge, perceptions, and attitudes of physicians regarding ARDs and MRONJ in osteoporosis patients was collected. Statistical analysis was performed for all variables, and their correlations were explored.

Results

A total of 221 physicians participated in the survey: 34.8% were rheumatologists, 25.3% were endocrinologists, 8.6% were family medicine physicians, 5.9% were orthopedists, and 5.9% were internal medicine physicians. Of them, 58.0% reported more than 6 years of experience. Only 78.7% were aware of MRONJ and recognized that bisphosphonates (BPs) can contribute to MRONJ. In contrast, 56.0% recognized denosumab as a causative factor for MRONJ. Duration of ARD therapy and pre- and post-ARD dental care were known to influence the risk of MRONJ by 62% and 65.6% of the participants, respectively. Only 41.6% and 31.2% of participants informed patients about MRONJ prior to BP and denosumab therapy, respectively. Only 25.3% and 20.8% referred patients to dentists before BP and denosumab therapy, respectively. Overall, 65.6% of the participants had a negative attitude toward MRONJ, and 34.4% had a positive attitude. A positive attitude was mostly observed among rheumatologists (55.8%) compared to other specialists (p <0.001). More years of experience were associated with a higher level of knowledge and positive attitude.

Conclusion

The findings of this study identified a notable gap in the awareness, knowledge and attitudes of physicians regarding MRONJ in osteoporosis patients. Continuing education programs about ARDs and MRONJ risk are highly recommended.

Is the LRINEC score useful for predicting necrotizing fasciitis as a complication of MRONJ?

INTRODUCTION

Necrotizing fasciitis as a complication of medication-related osteonecrosis of the jaw (MRONJ), which we named "ONJ-NF", has been sometimes reported. This study aimed to investigate the usefulness of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for predicting ONJ-NF.

MATERIALS AND METHODS

We included patients with acute MRONJ who required hospitalization at a single institution from April 2013 to June 2022. They were divided into two groups: patients with ONJ-NF and those with severe cellulitis as a complication of MRONJ, which we named "ONJ-SC." LRINEC scores were compared between the groups and the cut-off value of the score was set by creating a receiver operating characteristic curve.

RESULTS

Eight patients with ONJ-NF and 22 patients with ONJ-SC were included. The LRINEC score was significantly higher in patients with ONJ-NF (median: 8.0 points, range 6-10 points) than in those with ONJ-SC (median: 2.5 points, range 0-6 points). A LRINEC score of ≥ 6 points had a sensitivity of 100.0%, a specificity of 77.3%, and an area under the curve of 0.97. Among 6 parameters of LRINEC score, only C-reactive protein (CRP) and white blood cell count (WBC) had significant differences between two groups. Most of the patients with ONJ-NF were rescued by antibiotic therapy and surgical drainage including debridement of necrotic tissues, but unfortunately, one patient did not survive.

CONCLUSION

Our results suggested that the LRINEC score may be a useful diagnostic tool to predict ONJ-NF but valuating only CRP and WBC may be sufficient particularly in patients with osteoporosis.

Medication-related osteonecrosis of the jaw: the radiologist's role

In recent decades, the dreaded adverse effect of bisphosphonates, osteonecrosis of the jaw, has been widely reported and described in detail. Osteonecrosis of the jaw consists of the destruction of part of the maxilla as a consequence of these antiresorptive drugs. In recent years, new drugs that can also cause osteonecrosis of the jaw (e.g., some monoclonal antibodies or antiangiogenic drugs) have come on the market. For this reason, the term "bisphosphonate-related osteonecrosis of the jaw" has been replaced with "medication-related osteonecrosis of the jaw (MRONJ). This review aims to describe the radiologic characteristics of MRONJ that, although nonspecific, radiologists need to recognize in the appropriate clinical context.

Effect of agents affecting bone homeostasis on short- and long-term implant failure

OBJECTIVES

To review the current evidence on the relationship between agents that affect bone homeostasis and dental implant failures.

MATERIALS AND METHODS

Electronic searches for bisphosphonates, denosumab, methotrexate, corticosteroids, romosozumab, sunitinib, and bevacizumab were performed using PubMed, MEDLINE (OVID), EMBASE (OVID), Cochrane Central Register of Controlled Trials (Cochrane Library), Cochrane Oral Health Group Trials Register (Cochrane Library) and Web of Science (Thomson Reuters). Manual searches were also conducted to complement the digital searches for recent issues.

RESULTS

Previous publications suggested that bisphosphonates do not compromise the survival of dental implants. However, one study documented an increased risk of implant failure in patients who had received high-dose of intravenous bisphosphonate therapy after implant rehabilitation. There has been an issue of MRONJ around implants in patients who have successfully received implant therapy before and after antiresorptive therapy, leading to late implant failure. Despite evidence on the detrimental effects of denosumab, methotrexate and corticosteroids on bone metabolism, their role in implant survival is not conclusive.

CONCLUSIONS

At present, there is insufficient evidence to establish a potential connection between agents that affects bone homeostasis and implant failure. However, some studies have reported negative results for implant therapy. In addition, implant-related sequestration in patients who received anti-resorptive therapy, despite of successful osseointegration, is also noticeable. Although limited studies are available at present, clinicians should still carefully consider the potential hazards and take appropriate precautions to minimize the risks associated with the medications and implant therapy.

Post biphosphonate mandible osteonecrosis: A case study and literature review

Purpose

Bisphosphonates have proven effective in reducing pain and skeletal events in bone metastases treatment. However, there is a long-term complication called osteonecrosis of the jaw, which has been reported for more than a decade. Despite various professional recommendations, there is no international consensus on the best therapeutic strategy. Prevention is crucial, and a multidisciplinary approach must be tailored to each stage of the condition.

Design

We present a case of osteonecrosis of the jaw in a patient with metastatic breast cancer who was receiving 4 mg injectable zoledronic acid.

Result

The patient stopped treatment with zoledronic acid and received systemic treatment (analgesics, antibiotics), with the resolution of symptoms.

Conclusion

ONJ is a serious condition associated with taking BP that can impact oral health and quality of life. Our study highlights the effectiveness of systematic treatment in managing ONJ with BP-related alterations. Preventative measures, such as regular dental consultations, play a vital role in reducing the risk of ONJ. Multidisciplinary management is essential to addressing the different stages of the condition.

Call to action: a five nations consensus on the use of intravenous zoledronate after hip fracture

Currently in the UK and Ireland, after a hip fracture most patients do not receive bone protection medication to reduce the risk of refracture. Yet randomised controlled trial data specifically examining patients with hip fracture have shown that intravenous zoledronate reduces refracture risk by a third. Despite this evidence, use of intravenous zoledronate is highly variable following a hip fracture; many hospitals are providing this treatment, whilst most are currently not. A range of clinical uncertainties, doubts over the evidence base and practical concerns are cited as reasons. This paper discusses these concerns and provides guidance from expert consensus, aiming to assist orthogeriatricians, pharmacists and health services managers establish local protocols to deliver this highly clinically and cost-effective treatment to patients before they leave hospital, in order to reduce costly re-fractures in this frail population.