Case-Based Review of Osteonecrosis of the Jaw (ONJ) and Application of the International Recommendations for Management From the International Task Force on ONJ

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.

Unexpected Increase in Bone Mineral Density With Rapamycin and Low-Dose Naltrexone: A Case Report of a 52-Year-Old Woman With Osteopenia

Osteopenia and osteoporosis are prevalent bone disorders characterized by reduced bone mineral density (BMD), leading to an increased risk of fractures. This case report presents a 52-year-old Caucasian female patient with osteopenia who experienced an unexpected 15.9% increase in lumbar spine BMD within two years after enrolling in a clinical trial involving low-dose rapamycin and subsequently starting low-dose naltrexone. This case potentially opens novel treatment strategies for bone density improvement in aging populations.

Peri-implant medication-related osteonecrosis of the jaw mimicking endodontic disease in a cancer patient: A case report

Medication-related osteonecrosis of the jaw (MRONJ) is a progressive condition that can cause significant bone loss and its diagnosis can be challenging. A 68-year-old man with a diagnosis of hepatocellular carcinoma, undergoing treatment with atezolizumab, bevacizumab and zoledronic acid, complained of spontaneous pain in the right lower second premolar. Oral examination revealed no dental changes and implants in the right jaw. A patient history and thorough clinical and radiographic examinations mimic endodontic disease. The implant crowns were removed, bleeding on probing, and peri-implant pockets were observed. The main hypothesis was MRONJ Stage 2, and the surgical treatment was performed. The pain ceased and signs of MRONJ were not observed within 3 months. MRONJ should be considered as a hypothesis in the case of odontalgia and a patient's history of antiresorptive and antiangiogenic therapies. Furthermore, monitoring patients with dental implants in the mandible through detailed clinical and imaging evaluation is required.

Diagnosis and Management of Atypical Femoral Fractures and Medication-Related Osteonecrosis of the Jaw in Patients with Osteoporosis

Anti-osteoporosis treatments reduce fracture risk but maybe associated with rare adverse events with long-term use such as atypical femoral fractures (AFFs) and medication-related osteonecrosis of the jaw (MRONJ). AFFs are rare but more likely with prolonged bisphosphonate use, whereas MRONJ incidence is higher in cancer patients on high-dose antiresorptive therapy. Following diagnosis, effective treatment options are available to manage both of these rare complications. An individualized treatment approach is advised with close monitoring.

A practical approach for anabolic treatment of bone fragility with romosozumab

BACKGROUND

Romosozumab, a fully humanized anti-sclerostin-antibody, is a bone-builder stimulating osteoblasts and inhibiting osteoclast by activation of the canonical Wnt-beta catenin signaling. This unique mechanism of action has the potential to address unmet needs in osteoporosis management.

METHODS

The multifaceted practical clinical issues related to romosozumab are discussed, especially focusing on the rationale of employing a sclerostin inhibitor to target bone fragility as first line or second line treatment in post-menopausal osteoporosis and in males at increased risk of fractures.

RESULTS

Four randomized clinical trials with several post-hoc analyses and more than ten observational studies have consistently demonstrated that romosozumab is effective in rapidly increasing bone mineral density (BMD) and decreasing risk of vertebral, non-vertebral and hip fractures in post-menopausal women at very-high risk of fractures. In male osteoporosis, only data on BMD are available. Noteworthy, romosozumab was shown to be more effective and rapid than teriparatide in improving BMD, bone structure and strength at the hip, especially in women already treated with anti-resorptive drugs. Interestingly, even if romosozumab displays best results in treatment-naïve patients, its favourable effects on BMD were observed even in women previously treated with teriparatide or denosumab, although to a lesser extent.

CONCLUSIONS

Based on the available evidence, romosozumab could be proposed as ideal drug in several clinical settings, such as non-fractured post-menopausal women at very-high risk of fractures, patients with recent hip fracture, patients non responder to bisphosphonates and short-term denosumab therapy.

[Photobiomodulation with active oxygen and lactoferrin in the treatment of medication-related osteonecrosis of the jaw. A case report]

Medication-related osteonecrosis jaw (MRONJ) affects about 5% of patients treated with bisphosphonates and other similar drugs. This case report describes the management of a case of MRONJ using photobiomodulation therapy (FBM) combined with active oxygen and lactoferrin (Blue®M). This is a 62-year-old patient with hypertension, rheumatoid arthritis and osteoporosis treated with Bonames®. After extraction, she presented exposed bone in the alveolar ridge of quadrant III. Under informed consent, minimally invasive surgery was performed with electrical instruments (Piezotome®). Histopathological analysis revealed necrotic bone tissue with chronic inflammatory infiltrate. The treatment included Blue®M teeth&bone once a day for 30 days, topical application of Blue®M gel every morning for 15 days and FBM with 808nm diode laser (Therapy-DMC®). The laser sessions were daily until day 3, and then twice a week for four weeks. The patient also performed mouthwashes with Blue®M every night for 30 days. Initially, the patient reported pain of 3/10 on the visual analog scale, which decreased to 0/10 at the end of treatment. Clinically, soft tissue healing was observed at 30 days and 60 days and the CT scan showed hyperdense cancellous bone with well-formed cortical and no alterations. Finally, this case suggests that the combination of FBM with topical active oxygen therapy and lactoferrin, along with minimally invasive surgical intervention, holds promise for the management of MRONJ.

Phosphatidylserine-incorporated exosome mimetics encapsulating CXCR3 antagonist alleviate osteoporosis

Exosomes derived from mesenchymal stem cells are an active area of research due to their therapeutic potential in treating osteoporosis. To further harness their therapeutic performance in modulating bone resorption, we have equipped exosomes with osteoclast-targeting moieties on their surface as well as chemokine receptor antagonists blocking osteoclast recruitment. Phosphatidylserine (PS), a membrane lipid exerting immunosuppressive and phagocytic signals, was incorporated in the membrane of exosome mimetics (EMs) to achieve a marked affinity for osteoclast precursors and potential anti-resorptive effects. We also aimed to tackle a CXCL9-CXCR3 ligand-receptor axis, a critical signaling axis in regulating osteoclast precursor recruitment and differentiation at bone resorption sites, by encapsulating a chemical antagonist of CXCR3, AMG487, in the PS-incorporated EMs (PS-EMs). The osteoclast-targeting PS-EMs loaded with AMG487 effectively protected against bone loss in an ovariectomized mouse model. Our findings demonstrate the great promise of PS-EMs as anti-resorptive nanotherapies for alleviating osteoporosis.

Assessment of alendronate and dietary treatment in the management of feline idiopathic ionised hypercalcaemia and ionised hypercalcaemia associated with chronic kidney disease: 29 cases (2016-2022)

OBJECTIVES

This retrospective cohort multicentre study aimed to characterise the signalment, clinicopathologic data, complications and the association between treatment and outcome (the reduction in ionised calcium concentration) in cats with idiopathic or chronic kidney disease-associated ionised hypercalcaemia managed with alendronate and standard treatment or standard treatment alone, and to compare the outcome between the two groups.

MATERIALS AND METHODS

Medical records for cats diagnosed with idiopathic or chronic kidney disease-associated ionised hypercalcaemia were retrospectively reviewed. Cats treated with alendronate and standard treatment were assigned to the alendronate group and cats treated with standard treatment alone were assigned to the control group. The standard treatment was defined as dietary modification and/or monitoring of ionised calcium concentrations and management of complications secondary to hypercalcaemia. The follow-up period was selected as 6 months.

RESULTS

Twenty-nine cats were enrolled in the study. Nine cats were included in the control group and 20 cats in the alendronate group. A significant reduction in serum ionised calcium was observed in both groups between the baseline and the follow-up visit; however, this reduction did not differ significantly between both groups (the mean change in the ionised calcium concentration in alendronate and control group was -0.18 and -0.17, respectively). Suspected bisphosphate-related osteonecrosis of the jaw was reported in one cat receiving alendronate.

CLINICAL SIGNIFICANCE

In this study, similar reduction in serum ionised calcium concentration was observed in cats with ionised hypercalcaemia treated with diet alone and in cats treated with diet and alendronate. These results should be interpreted with caution, as the study was underpowered for meaningful statistical comparison. Cats receiving alendronate should be monitored for the development of adverse reactions, including osteonecrosis of the jaw.

Medication-related osteonecrosis of the jaw: Evaluation of a therapeutic strategy in oral surgery

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse illness linked to antiresorptive therapies (ART), for which there is no therapeutic gold standard. Many factors can influence MRONJ evolution such as cancer type, treatment, comorbidities, and accumulated dose of ART. The aim of this study was to determine the influencing factors of MRONJ treatments success.

METHODS

This retrospective study focused on patients treated for MRONJ in a French tertiary centre. Non-operative therapy was always applied, ART were suspended if appropriate, and surgery (MRONJ removal and musculo-mucosal flap reconstruction) was performed in the absence of contraindication. The evaluation criteria were bone and mucosal healing 3 months after surgery.

RESULTS

81 MRONJ were included; medical treatment alone was administered to 26 % while the remaining 74 % received additional surgery. Therapeutic success reached 86.7 % (52/60) for surgery compared to 42.9 % (9/21) for medical treatment alone (p < 0.001). Age (OR=1.08, p = 0.014) and the absence of infection (OR=5.32, p = 0.042) were in favour of success, while medical treatment alone (OR=0.03, p < 0.001) was highly unfavourable.

CONCLUSION

MRONJ healing is influenced by age, non-infectious stages, and surgery. Additional surgery in MRONJ treatment should be advised if the health of the patient permits.

The Incidence and Severity of Medication Related Osteonecrosis of the Jaws is Similar in Male and Female Mice

BACKGROUND

Medication related osteonecrosis of the jaws (MRONJ), a rare side-effect of antiresorptive medications, is described as exposed bone in the oral cavity that lasts for at least 8 weeks. Most studies report a female predilection for MRONJ; these findings could be due to the increased use of antiresorptives in females, or due to inherent differences between male versus female patients.

PURPOSE

The purpose of this study was to measure and compare the incidence and severity of osteonecrosis of the jaws (ONJ) between male and female mice.

STUDY DESIGN, SETTING, SAMPLE

We designed a randomized in-vivo animal study utilizing male and female mice treated with zoledronic acid (ZA). Experimental periodontitis was induced in 24 male and 24 female mice using a silk ligature following administration of saline or a potent bisphosphonate. After 8 weeks, animals were evaluated radiographically and histologically.

INDEPENDENT VARIABLE

The independent variables were sex (male vs female) and treatment group (ZA vs saline control). Treatment was randomly assigned with balanced distribution between male and female animals.

MAIN OUTCOME VARIABLE

The main outcome variable was ONJ status coded as present or absent. ONJ was defined as present if there was histologic contact between the ligature and the alveolar bone. Secondary outcomes of interest were radiographic and histologic parameters.

ANALYSIS

Statistical differences were analyzed using a two-way analysis of variance with Tukey's post hoc test using a P value of 0.05 for significance.

RESULTS

The final sample was composed of 24 vehicle treated and 24 ZA treated animals. In vehicle treated animals, 8% of female and 8% of male animals developed ONJ. In ZA treated animals, 83% of female and 92% of male animals developed ONJ. Sex was not associated with the risk (measured as incidence of disease) for developing ONJ or in the radiographic or histologic parameters that were assessed (P values >.1).

CONCLUSIONS

Sex does not appear to affect the incidence of MRONJ or the severity of the disease as assessed by the radiographic and histologic parameters.

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.

A Systematic Review of Laser Photobiomodulation Dosimetry and Treatment Protocols in the Management of Medications-Related Osteonecrosis of the Jaws: A Rationalised Consensus for Future Randomised Controlled Clinical Trials

Medication-related osteonecrosis of the jaw (MRONJ) is a debilitating adverse effect of bisphosphates, antiresorptive therapy or antiangiogenic agents that can potentially increase oxidative stress, leading to progressive osteonecrosis of the jaws. Despite the large number of published systematic reviews, there is a lack of potential MRONJ treatment protocols utilising photobiomodulation (PBM) as a single or adjunct therapy for preventive or therapeutic oncology or non-oncology cohort. Hence, this systematic review aimed to evaluate PBM laser efficacy and its dosimetry as a monotherapy or combined with the standard treatments for preventive or therapeutic approach in MRONJ management. The objectives of the review were as follows: (1) to establish PBM dosimetry and treatment protocols for preventive, therapeutic or combined approaches in MRONJ management; (2) to highlight and bridge the literature gaps in MRONJ diagnostics and management; and (3) to suggest rationalised consensus recommendations for future randomised controlled trials (RCTs) through the available evidence-based literature. This review was conducted according to the PRISMA guidelines, and the protocol was registered at PROSPERO under the ID CRD42021238175. A multi-database search was performed to identify articles of clinical studies published from their earliest records until 15 December 2023. The data were extracted from the relevant papers and analysed according to the outcomes selected in this review. In total, 12 out of 126 studies met the eligibility criteria. The striking inconsistent conclusions made by the various authors of the included studies were due to the heterogeneity in the methodology, diagnostic criteria and assessment tools, as well as in the reported outcomes, made it impossible to conduct a meta-analysis. PBM as a single or adjunct treatment modality is effective for MRONJ preventive or therapeutic management, but it was inconclusive to establish a standardised and replicable protocol due to the high risk of bias in a majority of the studies, but it was possible to extrapolate the PBM dosimetry of two studies that were close to the WALT recommended parameters. In conclusion, the authors established suggested rationalised consensus recommendations for future well-designed robust RCTs, utilising PBM as a monotherapy or an adjunct in preventive or therapeutic approach of MRONJ in an oncology and non-oncology cohort. This would pave the path for standardised PBM dosimetry and treatment protocols in MRONJ management.

[Update of the S3-guideline on diagnostics, prophylaxis and treatment of osteoporosis]

With the aid of a new fracture risk model, the great treatment gap for osteoporosis should be closed. All patients older than 70 years should undergo a diagnostic procedure for osteoporosis. An additional risk threshold (≥ 10% per 3 years for femoral and vertebral fractures) should enable patients with a high risk of fracture to be treated with osteoanabolic agents. The use of osteoanabolic agents makes it necessary to administer antiresorptive drugs afterwards. Due to the low event rate of osteonecrosis of the jaw, the initiation of a specific osteoporosis treatment should not be delayed by prophylactic dental treatment. The adherence to the drug treatment should be improved by an individualized approach on the basis of a cooperation between patients, caregivers, and physicians. A regular assessment of falls, including the timed up and go test should be carried out in patients older than 70 years.

Treatment of Medication-Related Osteonecrosis of the Jaws (MRONJ) with Topical Therapy Using Active Oxygen Gel

Medication-related osteonecrosis of the jaw (MRONJ) can be a debilitating complication that can arise in patients who took or are taking antiresorptive (including bisphosphonates) or antiangiogenic agents, leading to visible bone or a fistula that continues for more than eight weeks, without any history of radiotherapy. This clinical case aimed to describe the treatment of MRONJ with topical active oxygen therapy using blue®m oral gel. A 63-year-old female patient that had been taking weekly sodium alendronate (70 mg) for four years by oral via, presented discomfort and implant movement in the #46 region, by that underwent surgical extraction of the implant. After three months the patient returned and was diagnosed with MRONJ. Initially, conventional therapies were performed, including surgical debridement and antibiotic therapy, but without success. The patient still had clinical signs of osteonecrosis six months after the implant extraction. The entire socket was then filled with blue®m oral gel by topical application. The patient was instructed to continue applying the gel to the region every 8 hours for 15 days. After this period, the patient returned, and it was observed that the wound was in the healing process, with the presence of epithelialized tissue and without bone exposure. The 2-year clinical follow-up showed the lesion had healed entirely, and a new implant was installed. After the osseointegration period, the final prosthesis was placed. The patient remains under clinical follow-up. Therefore, it can be concluded that the application of blue®m oral gel in this clinical case assisted in the recovery of the osteonecrosis lesion.

Antiresorptive agents enhance ossification of free flap reconstructions of the mandible: a radiological retrospective cohort study

Background

The aim of this study was to investigate the effect of antiresorptive agents on the ossification of reconstructed mandibles by free bone grafts for the first time.

Methods

A total of 38 reconstructions of the jaw were retrospectively evaluated for ossification between bone segments by two raters based on postoperative panoramic radiographs. The study group (n = 13) had segmental resection of the mandible and free bone flap reconstruction due to medication-related osteonecrosis of the jaw (MRONJ). The control group (noMRONJ, n = 25) comprised segmental mandibular resections and free bone flap reconstructions due to tumors, chronic osteomyelitis, or trauma without any radiation. Ossification time and influencing factors were evaluated.

Results

Both duration of surgery (346 ± 90 min. vs. 498 ± 124 min.; p < 0.001) and hospitalization (8.7 ± 2.8 days vs. 13.4 ± 5.3 days, p = 0.006) were shorter in the MRONJ group compared to the noMRONJ group. Ossification after mandibular reconstruction was significantly faster in the MRONJ study group [224 days, interquartile range (IQR) 175-287] compared to the control group (288 days, IQR 194-445; p < 0.001). Moreover, good initial contact between the segments resulted in faster ossification (p < 0.001) in the MRONJ group. Ossification rate between original and grafted bone or between grafted bone segments only did not differ in both the study and control groups (MRONJ, p = 0.705 vs. control, p = 0.292). The type of antiresorptive agent did not show any significance for ossification. The rate of wound healing disturbances did also not differ between the study and control groups (p = 0.69).

Conclusion

Advanced MRONJ (stage 3) can be resected and reconstructed safely with free microvascular bone flaps. Antiresorptive agents enhance the ossification of the bone segments. Optimal initial contact of the bone segments accelerates bone healing. Surgery and hospitalization are markedly shortened in this vulnerable group of MRONJ patients compared to oncologic patients.

Mitigating jaw osteonecrosis: bioactive glass and pericardial membrane combination in a rat model

Objectives

Bisphosphonates (BFs) show clinical effectiveness in managing osteoporosis and bone metastases but pose risks of bisphosphonate-related jaw osteonecrosis (BRONJ). With no established gold standard for BRONJ treatment, our focus is on symptom severity reduction. We aimed to assess the preventive effects of bioactive glass and/or pericardial membrane in a preclinical BRONJ model, evaluating their potential to prevent osteonecrosis and bone loss post-tooth extractions in zoledronic acid (ZA)-treated animals.

Methods

Rats, receiving ZA or saline biweekly for four weeks, underwent 1st and 2nd lower left molar extractions. Pericardial membrane alone or with F18 bioglass was applied post-extractions. Microarchitecture analysis and bone loss assessment utilized computerized microtomography (CT) and positron emission tomography (PET) with 18F-FDG and 18F-NaF tracers. Histological analysis evaluated bone injury.

Results

Exclusive alveolar bone loss occurred post-extraction in the continuous ZA group, inducing osteonecrosis, osteolysis, osteomyelitis, and abscess formation. Concurrent pericardial membrane with F18 bioglass application prevented these outcomes. Baseline PET/CT scans showed no discernible uptake differences, but post-extraction 18F-FDG tracer imaging revealed heightened glucose metabolism at the extraction site in the ZA-treated group with membrane, contrasting the control group.

Conclusion

These findings suggest pericardial membrane with F18 bioglass effectively prevents BRONJ in the preclinical model.

Pulp and periapical disease as a risk factor for osteonecrosis of the jaw: a national cohort-based study in Korea

PURPOSE

This longitudinal cohort study aimed to evaluate the relationship between osteonecrosis of the jaw and pulp and periapical disease in patients who were administered bisphosphonates.

METHODS

Using data from a nationwide cohort, we examined the association among dental caries, pulp and periapical disease, and osteonecrosis of the jaw in women aged >50 years who received bisphosphonates for more than 1 year between 2002 and 2015. Because of ambiguities in the diagnosis of osteonecrosis of the jaw in population-based data, we operationally defined and categorized the condition into established and potential osteonecrosis of the jaw.

RESULTS

Pulp and periapical disease significantly increased the development of both established and potential osteonecrosis of the jaw (hazard ratio, 2.21; 95% confidence interval, 1.40-3.48; and hazard ratio, 2.22; 95% confidence interval, 1.65-2.98, respectively). Root canal treatment did not have any influence on the development of osteonecrosis of the jaw.

CONCLUSIONS

Pulp and periapical disease may be a major risk factor for osteonecrosis of the jaw. The study findings suggest that patients should undergo regular dental examinations to detect pulp and periapical disease before or during the administration of bisphosphonates and that root canal treatment should be considered to decrease the risk of osteonecrosis of the jaw.

Exploring the Impact of Novel Anti-Cancer Therapies on Jaw Osteonecrosis and Other Bones: A Comprehensive Review

Osteonecrosis is a debilitating condition characterized by the loss of blood supply to the bones, leading to bone death. This condition can impact various bones, including the jaw, which significantly affects patients' quality of life by causing difficulties in swallowing, feeding, chewing, and speaking, along with swollen, painful mucous membranes and chronic sinusitis. Osteonecrosis can arise due to treatment with antiresorptive drugs. However, there is a growing number of reports of osteonecrosis following novel targeted anti-cancer treatments, such as tyrosine kinase inhibitors (TKIs) and biological therapies. The pathogenesis of osteonecrosis is linked to the side effects of the antiangiogenic mechanisms of these medications, leading to a disrupted blood flow. Our review aims to examine recent insights into osteonecrosis triggered by new anti-cancer drugs. Most reports focus on the osteonecrosis of the jaw (ONJ); however, we discovered that some authors have described cases of osteonecrosis affecting the femoral head or elbow following novel anti-cancer treatments. Prevention is a key component in managing osteonecrosis. Therefore, a comprehensive risk assessment should always be performed before and during anti-cancer therapy.

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.

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.

Peri-implantitis increases the risk of medication-related osteonecrosis of the jaws associated with osseointegrated implants in rats treated with zoledronate

This study evaluated the peri-implant tissues under normal conditions and under the influence of experimental peri-implantitis (EPI) in osseointegrated implants installed in the maxillae of rats treated with oncologic dosage of zoledronate. Twenty-eight senescent female rats underwent the extraction of the upper incisor and placement of a titanium dental implant (DI). After eight weeks was installated a transmucosal healing screw on DI. After nine weeks, the following groups were formed: VEH, ZOL, VEH-EPI and ZOL-EPI. From the 9th until the 19th, VEH and VEH-EPI groups received vehicle and ZOL and ZOL-EPI groups received zoledronate. At the 14th week, a cotton ligature was installed around the DI in VEH-EPI and ZOL-EPI groups to induce the EPI. At the 19th week, euthanasia was performed, and the maxillae were processed so that at the implanted sites were analyzed: histological aspects and the percentage of total bone tissue (PTBT) and non-vital bone tissue (PNVBT), along with TNFα, IL-1β, VEGF, OCN and TRAP immunolabeling. ZOL group presented mild persistent peri-implant inflammation, higher PNVBT and TNFα and IL-1β immunolabeling, but lower for VEGF, OCN and TRAP in comparison with VEH group. ZOL-EPI group exhibited exuberant peri-implant inflammation, higher PNVBT and TNFα and IL-1β immunolabeling when compared with ZOL and VEH-EPI groups. Zoledronate disrupted peri-implant environment, causing mild persistent inflammation and increasing the quantity of non-vital bone tissue. Besides, associated with the EPI there were an exacerbated inflammation and even greater increase in the quantity of non-vital bone around the DI, which makes this condition a risk factor for medication-related osteonecrosis of the jaws.

Osteoporosis

Osteoporosis is a common systemic skeletal disorder resulting in bone fragility and increased fracture risk. Evidence-based screening strategies improve identification of patients who are most likely to benefit from drug treatment to prevent fracture. In addition, careful consideration of when pharmacotherapy should be started, choice of medication, and duration of treatment maximizes the benefits of fracture prevention while minimizing potential harms of long-term drug exposure.

[Update of the S3-guideline on diagnostics, prophylaxis and treatment of osteoporosis]

With the aid of a new fracture risk model, the great treatment gap for osteoporosis should be closed. All patients older than 70 years should undergo a diagnostic procedure for osteoporosis. An additional risk threshold (≥ 10% per 3 years for femoral and vertebral fractures) should enable patients with a high risk of fracture to be treated with osteoanabolic agents. The use of osteoanabolic agents makes it necessary to administer antiresorptive drugs afterwards. Due to the low event rate of osteonecrosis of the jaw, the initiation of a specific osteoporosis treatment should not be delayed by prophylactic dental treatment. The adherence to the drug treatment should be improved by an individualized approach on the basis of a cooperation between patients, caregivers, and physicians. A regular assessment of falls, including the timed up and go test should be carried out in patients older than 70 years.

Alloplastic reconstruction of the mandible after subtotal mandibulectomy for medication-related osteonecrosis of the jaw: An update of the method

BACKGROUND

Reconstruction of continuity defects following osteonecrosis in multimorbid patients is challenging. In all cases of the predescribed palliative treatment method for alloplastic mandible reconstruction, plate fractures were detected in follow-up. We hypothesized that a modification could avoid these fractures, leading to stable long-term results.

METHODS

This retrospective study compares the original method with a modification using single, laser-sintered CAD-CAM plates instead of manually bent miniplates. The predescribed shuttering technique was used to reconstruct the mandible in its original shape with bone cement.

RESULTS

Uneventful wound healing was observed in 86% of the cases after modification of the method. No implant or plate fracture occurred.

CONCLUSIONS

The presented method should be considered as a treatment option for mandible reconstruction in elderly, multimorbid patients in palliative situations. The results of this study suggest that the modification of the method leads to significantly improved long-term stability. Donor site morbidity is avoided with this method of palliative surgery.

Long-term and sequential treatment for osteoporosis

Osteoporosis is a skeletal disorder that causes impairment of bone structure and strength, leading to a progressively increased risk of fragility fractures. The global prevalence of osteoporosis is increasing in the ageing population. Owing to the chronic character of osteoporosis, years or even decades of preventive measures or therapy are required. The long-term use of bone-specific pharmacological treatment options, including antiresorptive and/or osteoanabolic approaches, has raised concerns around adverse effects or potential rebound phenomena after treatment discontinuation. Imaging options, risk scores and the assessment of bone turnover during initiation and monitoring of such therapies could help to inform individualized treatment strategies. Combination therapies are currently used less often than 'sequential' treatments. However, all patients with osteoporosis, including those with secondary and rare causes of osteoporosis, as well as specific patient populations (for example, young adults, men and pregnant women) require new approaches for long-term therapy and disease monitoring. New pathophysiological aspects of bone metabolism might therefore help to inform and revolutionize the diagnosis and treatment of osteoporosis.

Intravenous zoledronate for postmenopausal women with osteopenia and osteoporosis: a systematic review and metanalysis

BACKGROUND

Osteoporosis compromises bone strength and increases the risk of fractures. Zoledronate prevents loss of bone mass and reduces the risk of fractures.

OBJECTIVES

To determine the efficacy and safety of zoledronate in postmenopausal women with osteopenia and osteoporosis.

DESIGN AND SETTINGS

A systematic review and meta-analysis was conducted within the evidence-based health program at the Universidade Federal de São Paulo.

METHODS

An electronic search of the CENTRAL, MEDLINE, Embase, and LILACS databases was performed until February 2022. Randomized controlled trials comparing zoledronate with placebo or other bisphosphonates were included. Standard methodological procedures were performed according to the Cochrane Handbook and the certainty of evidence for the Grading of Recommendations Assessment, Development, and Evaluation Working Group. Two authors assessed the risk of bias and extracted data on fractures, adverse events, bone turnover markers (BTM), and bone mineral density (BMD).

RESULTS

Twelve trials from 6,652 records were included: nine compared zoledronate with placebo, two trials compared zoledronate with alendronate, and one trial compared zoledronate with ibandronate. Zoledronate reduced the incidence of fractures in osteoporotic [three years: morphometric vertebral fractures (relative risk, RR = 0.30 (95% confidence interval, CI: 0.24-0.38))] and osteopenic women [six years: morphometric vertebral fractures (RR = 0.39 (95%CI: 0.25-0.61))], increased incidence of post-dose symptoms [RR = 2.56 (95%CI: 1.80-3.65)], but not serious adverse events [RR = 0.97 (95%CI: 0.91-1.04)]. Zoledronate reduced BTM and increased BMD in osteoporotic and osteopenic women.

CONCLUSION

This review supports the efficacy and safety of zoledronate in postmenopausal women with osteopenia for six years and osteoporosis for three years.

PROSPERO REGISTRATION NUMBER

CRD42022309708, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=309708.

The Use of Human Amniotic Membrane (hAM) as a Treatment Strategy of Medication-Related Osteonecrosis of the Jaw (MRONJ): A Systematic Review and Meta-Analysis of the Literature

Background and objectives: Although it is very uncommon, medication-induced osteonecrosis of the jaw (also known as MRONJ) can have serious consequences. Traditionally, this adverse event has been recognised in patients who were treated with bisphosphonate (BP) drugs. Nevertheless, in recent years, it has been established that individuals having treatment with various types of medications, such as a receptor activator of nuclear factor kappa-Β ligand inhibitor (denosumab) and antiangiogenic agents, have had the same issue. The purpose of this research is to determine if the application of human amniotic membrane (hAM) may be used as a therapy for MRONJ. Material and Methods: A multi-source database (MEDLINE, EMBASE, AMED, and CENTRAL) systematic search was performed. The major objective of this study is to obtain an understanding of the efficacy of hAM when it is employed as a treatment modality for MRONJ. The protocol of this review was registered in the INPLASY register under the number NPLASY202330010. Results: The authors were able to include a total of five studies for the quality analysis, whereas for the quantity evaluation, only four studies were eligible. A total of 91 patients were considered for the investigation. After treatment with human amniotic membrane (hAM), a recurrence of osteonecrosis was observed in n = 6 cases (8.8%). The combined efficacy of surgical therapy and the use of hAM resulted in an overall success rate of 91.2%. Intraoperative complications were only documented in one article, and they were mostly caused by the positioning of the hAM, which led to wound breakdown at the surgical site. Conclusions: Based on the small amount of data and low-quality research included in this study, using human amniotic membranes to treat MRONJ might represent a feasible option. Nevertheless, further studies with a wider patient population are required to understand the long-term impacts.

Evaluation of Medication-Related Osteonecrosis of the Jaw (MRONJ) in Terms of Staging and Treatment Strategies by Dental Students at Different Educational Levels

Background: The role of medication-related osteonecrosis of the jaw (MRONJ) as a dento-maxillo-facial pathology is becoming increasingly important due to its growing prevalence. The success of preventive and therapeutic measures relies mainly on the dentist's ability to correctly diagnose the disease. Methods: The aim of this study was to evaluate the skills of dental students of different educational levels in choosing the correct stage, diagnostics, and treatment option for MRONJ based on clinical and radiographic imaging (panoramic radiograph, CBCT). The study was designed as a cross-sectional cohort study. Twenty dental students were asked to complete a questionnaire in their third and fifth year of studies in which they had to correctly stage the disease, choose the radiological diagnostics and recommend the treatment. The control group contained experienced oral and maxillofacial surgeons. Results: With an overall performance of 59% (third year: 145.2/248 points; fifth year: 145.3/248 points), no statistically significant difference between the educational levels could be observed. The classification based on CBCT imaging was significantly more often correct compared to panoramic radiographs (p < 0.001). Conclusions: This study highlights students' lack of knowledge in staging, diagnostics, and treatment of MRONJ, even though the CBCT positively affected decision-making. No significant increase in knowledge could be confirmed through clinical education. This study highlights the need for students to catch up on MRONJ diagnostics and treatment planning. Further expansion of teaching in this disease's context and X-ray diagnostics is needed.

The effect of drug holiday on preventing medication-related osteonecrosis of the jaw in osteoporotic rat model

Background

Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication associated with antiresorptive medications managing osteoporosis, such as bisphosphonates (BPs). To date, there is very limited evidence from prospective, controlled studies to support or refute the controversial prevention regimen that if a discontinuation of BPs before dentoalveolar surgery, so called "drug holiday", is effective in reducing the risk of MRONJ development in patients with osteoporosis. We proposed an experimental animal study, aiming to investigate the prevention of MRONJ following tooth extractions in osteoporotic condition, with the implementation of a BP drug holiday.

Methods

Twenty rats were subjected to bilateral ovariectomy. After establishing the osteoporotic condition, all rats were exposed to weekly injections of zoledronate acid (ZA) for 8 weeks. After ZA treatment, 10 rats were subjected to dental extraction and defined as control group, and the rest 10 rats assigned to the DH group had a drug holiday of 8 weeks prior to dental extraction. Eight weeks after the dentoalveolar surgery, bone turnover biomarker in serum, occurrence of MRONJ-like lesion and histomorphometric assessment of osteonecrosis in mandible, and bone microarchitecture indices in femur, were examined.

Results

Eight weeks after dental extraction, the DH group showed a recovered osteoclastic activity, indicated by significantly increased number of osteoclasts in the mandibles and serum level of C-terminal telopeptides of type I collagen, as compared to the control group. No significant differences were observed in the gross-view and histological occurrences of MRONJ-like lesions between the two groups.There was no significant difference in bone microarchitecture in the femur between the control and DH groups before ZA therapy and 8 weeks after dental extraction.

Conclusion

Our data provided the first experimental evidence in the osteoporotic animal model that the implementation of a BP holiday in prior to dental extractions could partially recover osteoclastic activity, but could not alleviate the development of MRONJ-like lesion or exacerbate the osteoporotic condition in the femur. Longer-term drug holiday, or combination of drug holiday and other prophylaxes to prevent MRONJ in patients with osteoporosis could be worth exploring in future studies, to pave the way for clinical managements.

The translational potential of this article

This in vivo prospective study reported that a recovery of osteoclastic activity by a BP drug holiday for 8 weeks in osteoporosis rats did not alleviate the development of MRONJ-like lesion followed by dental extractions. It contributes to the understanding of regimens to prevent MRONJ.

Effect of Bifidobacterium on osteoclasts: TNF-α/NF-κB inflammatory signal pathway-mediated mechanism

Osteoporosis is a systemic multifactorial bone disease characterized by low bone quality and density and bone microstructure damage, increasing bone fragility and fracture vulnerability. Increased osteoclast differentiation and activity are important factors contributing to bone loss, which is a common pathological manifestation of bone diseases such as osteoporosis. TNF-a/NF-κB is an inflammatory signaling pathway with a key regulatory role in regulating osteoclast formation, and the classical pathway RANKL/RANK/OPG assists osteoclast formation. Activation of this inflammatory pathway promotes the formation of osteoclasts and accelerates the process of osteoporosis. Recent studies and emerging evidence have consistently demonstrated the potential of probiotics to modulate bone health. Secretions of Bifidobacterium, a genus of probiotic bacteria in the phylum Actinobacteria, such as short-chain fatty acids, equol, and exopolysaccharides, have indicated beneficial effects on bone health. This review discusses the molecular mechanisms of the TNF-a/NF-κB inflammatory pathway in regulating osteoclast formation and describes the secretions produced by Bifidobacterium and their potential effects on bone health through this pathway, opening up new directions for future research.

Effectiveness of antimicrobial photodynamic therapy mediated by butyl toluidine blue in preventing medication-related osteonecrosis of the jaws in rats

BACKGROUND

Medication-related osteonecrosis of the jaws (MRONJ) is difficult to treat, therefore, prevention would be the ideal clinical approach. This study evaluated the effectiveness of antimicrobial photodynamic therapy (aPDT), mediated by butyl toluidine blue (BuTB) in the prevention of MRONJ-like lesions after tooth extraction in rats.

METHODS

Twenty-eight senescent female rats were distributed in groups: VEH and VEH-aPDT, treated with vehicle, ZOL and ZOL-aPDT, treated with 100 µg/Kg of zoledronate, both treatments every three days over seven weeks. After three weeks from the commencement of treatment, the mandibular first molar was extracted. For the VEH and ZOL groups, no local treatment was performed, while with the VEH-aPDT and ZOL-aPDT groups, photodynamic treatment was carried out at 0, 2, and 4 days after extraction. For aPDT, 500μl of BuTB solution was deposited on the dental extraction site (0.5 mg/ml; 60 s), followed by irradiation with low-level laser (InGaAIP; 660 nm; 35 mW; 74.2 J/cm²; 60 s). After 28 postoperative days, euthanasia was performed. The hemimandibles were processed to: (1) histological analysis of tissue repair; (2) histometric analysis of the percentage of newly formed bone tissue (PNFBT) and percentage of non-vital bone tissue (PNVBT); (3) immunohistochemical analysis for tartrate-resistant acid phosphatase (TRAP).

RESULTS

The ZOL and ZOL-aPDT groups showed less TRAP-positive cells when compared with VEH and VEH-aPDT. The ZOL group demonstrated great compromise in the tissue repair process, consistent with MRONJ-like lesions. VEH, VEH-aPDT and ZOL-aPDT presented a favorable tissue repair process. PNFBT in the ZOL group was lower than in the VEH, VEH-aPDT and ZOL-aPDT groups, whereas PNVBT in the ZOL group was higher than in the VEH, VEH-aPDT and ZOL-aPDT groups.

CONCLUSION

aPDT mediated by BuTB prevented the occurrence of MRONJ-like lesions after tooth extraction in rats.

Clinical risk factors for severity and prognosis of antiresorptive agent-related osteonecrosis of the jaw: a retrospective observational study

INTRODUCTION

The incidence of antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is rare, and its management has not yet been established. This study aimed to investigate the predictors for advanced stage and healing of ARONJ to establish an appropriate treatment strategy.

MATERIALS AND METHODS

We retrospectively analyzed patients diagnosed with ARONJ at Kobe City Medical Center General Hospital between April 2014 and March 2020. Outcomes were defined as stage ≥ 2 ARONJ (primary) and healing of ARONJ (secondary). Multivariate logistic regression analysis was used to detect factors associated with the outcomes, and odds ratios (OR) and 95% confidence intervals (CI) were calculated.

RESULTS

This study included 143 patients (stage ≥ 2 ARONJ, 51%; healing of ARONJ, 60%). Multivariate logistic regression analysis revealed that advanced age (per year) (OR 1.037; 95% CI 1.003-1.072; p = 0.028) and serum albumin (per g/dL) (OR 0.430; 95% CI 0.213-0.869; p = 0.018) were significantly associated with stage ≥ 2 ARONJ. Furthermore, multivariate logistic regression analysis revealed that cancer (yes) (OR 0.099; 95% CI 0.029-0.339; p < 0.001), conservative surgical treatment (yes) (OR 15.42; 95% CI 5.657-42.0; p < 0.001), C-reactive protein (per mg/dL) (OR 0.599; 95% CI 0.415-0.864; p < 0.001), and vitamin D analog (yes) (OR 0.167; 95% CI 0.034-0.827; p = 0.028) were factors associated with healing.

CONCLUSION

Our findings suggest that age and hypoalbuminemia are associated with the severity of ARONJ, and cancer, high inflammation, and vitamin D analog may impair healing. In contrast, conservative surgical treatment can overcome the poor treatment outcomes associated with ARONJ.

Medication-related osteonecrosis of the jaw after tooth extraction in patients receiving pharmaceutical treatment for osteoporosis: A retrospective cohort study

Background/purpose

Bone resorption inhibitors, such as bisphosphonates (BPs) and anti-receptor activator of nuclear factor kappa B ligand antibodies (denosumab; Dmab), are used to treat osteoporosis and effectively reduce the risk of fracture. However, medication-related osteonecrosis of the jaw (MRONJ) has been reported as a rare adverse effect. Invasive tooth extraction procedures are reportedly a factor in the development of MRONJ. In this study, we aimed to retrospectively observe and clinically examine the effect of medication status on MRONJ development after tooth extraction in patients receiving drug treatment for osteoporosis.

Materials and methods

This study was conducted among patients who visited our hospital between December 2015 and December 2021. We collected and analyzed the medical information of patients who underwent dental extractions while using osteoporosis medications, including oral and injectable BPs and Dmab.

Results

Among antiresorptive medication users, 40 patients (70 teeth) underwent extraction. The mean duration of BP/Dmab use was 40.4 months, and the mean duration of drug holiday was 6.9 months. MRONJ after tooth extraction was not seen in BP users, but we observed two cases in Dmab users. A significant difference in MRONJ development was confirmed with the use of injectable compared with oral medication administration (odds ratio＝5.01).

Conclusion

The use of injectable bone resorption inhibitors was associated with a higher risk of developing MRONJ. The route of administration, duration of medication, and withdrawal period should be carefully considered to prevent MRONJ after tooth extraction.

Risk factors for medication-related osteonecrosis of the jaw and salivary IL-6 IN cancer patients

Introduction

Medication-related osteonecrosis of the jaws is a severe complication of the use of antiresorptive and antiangiogenic therapy, with limited treatment options and great impact on patient’s quality pf life.

Objective

The aim of this study was to assess the risk factors associated with medication-related osteonecrosis of the jaws in oncologic patients undergoing bisphosphonate treatment. In addition, salivary levels of interleukin-6, IL-6, were measured to investigate their association with severity and risk of medication-related osteonecrosis of the jaws.

Methods

Case-control study with 74 patients with bone metastases from solid tumors and multiple myeloma was included. Patients were divided into three groups: 1) those undergoing bisphosphonate treatment with medication-related osteonecrosis of the jaws; 2) those undergoing bisphosphonate without medication-related osteonecrosis of the jaws; and 3) those with bisphosphonate pretreatment. The demographic and medical data of the patients were collected to assess risk. The clinical evaluation was performed to diagnose medication-related osteonecrosis of the jaws and unstimulated saliva was collected for quantification of IL-6.

Results

As result, it was observed that patients diagnosed with medication-related osteonecrosis of the jaws were submitted to higher number of bisphosphonate doses (p = 0.001) and monthly infusion protocol (p = 0.044; OR = 7.75). Patients who did not have routine followup with specialized dentists during therapy with bisphosphonate and smoking were associated with medication-related osteonecrosis of the jaws (p = 0.019; OR = 8.25 and p = 0.031; OR = 9.37 respectively). Group 1 had a higher frequency of treatment with chemotherapy and corticosteroids concomitant with bisphosphonate, and surgical dental procedures (p = 0.129). Salivary IL-6 levels showed no statistically significant difference between the groups (p = 0.571) or association with medication-related osteonecrosis of the jaws severity (p = 0.923).

Conclusion

A higher number of bisphosphonate cycles, monthly infusion protocol, no dental follow-up for oral health maintenance and smoking were associated with medication-related osteonecrosis of the jaws. Specialized dental follow up during bisphosphonate treatment has been shown to be an important factor in preventing this complication.

Osteoporosis and Fragility Fractures: currently available pharmacological options and future directions

Osteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. The average lifetime risk of a 50-year-old woman to suffer a fracture of the spine, hip, proximal humerus, or distal forearm has been estimated at close to 50%. In general, pharmacological treatment is recommended in patients who suffered a fragility fracture because their risk of suffering a subsequent fracture is increased dramatically. Therefore, many guidelines recommend pharmacological treatment in patients without a prevalent fracture if their fracture probability is comparable to or higher than that of a person of the same age with a prevalent fracture. The present review aims to highlight currently available pharmacological treatment options and their antifracture efficacy including safety aspects. Drug classes discussed comprise bisphosphonates, selective estrogen receptor modulators, parathyroid hormone peptides and derivatives, humanized monoclonal antibodies, and estrogens and gestagens and their combinations. Furthermore, a brief glimpse is provided into a potentially promising treatment option that involves mesenchymal stem cells.

Mechanism of bisphosphonate-related osteonecrosis of the jaw (BRONJ) revealed by targeted removal of legacy bisphosphonate from jawbone using competing inert hydroxymethylene diphosphonate

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) presents as a morbid jawbone lesion in patients exposed to a nitrogen-containing bisphosphonate (N-BP). Although it is rare, BRONJ has caused apprehension among patients and healthcare providers and decreased acceptance of this antiresorptive drug class to treat osteoporosis and metastatic osteolysis. We report here a novel method to elucidate the pathological mechanism of BRONJ by the selective removal of legacy N-BP from the jawbone using an intra-oral application of hydroxymethylene diphosphonate (HMDP) formulated in liposome-based deformable nanoscale vesicles (DNV). After maxillary tooth extraction, zoledronate-treated mice developed delayed gingival wound closure, delayed tooth extraction socket healing and increased jawbone osteonecrosis consistent with human BRONJ lesions. Single cell RNA sequencing of mouse gingival cells revealed oral barrier immune dysregulation and unresolved proinflammatory reaction. HMDP-DNV topical applications to nascent mouse BRONJ lesions resulted in accelerated gingival wound closure and bone socket healing as well as attenuation of osteonecrosis development. The gingival single cell RNA sequencing demonstrated resolution of chronic inflammation by increased anti-inflammatory signature gene expression of lymphocytes and myeloid-derived suppressor cells. This study suggests that BRONJ pathology is related to N-BP levels in jawbones and demonstrates the potential of HMDP-DNV as an effective BRONJ therapy.

Medication-related osteonecrosis of the jaw in cancer patients: Case series and review of the current literature

Currently, a large proportion of cancer patients are treated with bone modifying agents (BMA). In this regard, the increase in the prescription of these drugs has lead to concerns in the increment of osteonecrosis of the jaws. This article describes four patients with BMA cancer treatments requested dental evaluation at our institution due to pain and swelling of the mandibular bone after tooth extraction, tooth loss, or unknown risk factor. Oral and radiographic evaluation reveals Medication-related osteonecrosis of the jaw (MRONJ) at different clinical stages according to the American Association of Oral and Maxillofacial Surgeons (AAOMS) classification. Some patients underwent abscess drainage, oral cleaning and antibiotic therapy with complete recovery. Follow-up showed treatment success in all patients. That is why we emphasize the importance of early establishment of appropriate treatment and emphasize the avoidance of dental procedures during BMA therapy.

Long-Term Ligature-Induced Periodontitis Exacerbates Development of Bisphosphonate-Related Osteonecrosis of the Jaw in Mice

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a detrimental intraoral lesion that occurs in patients with long-term or high-dose use of anti-resorptive agents such as bisphosphonates. Tooth extraction is a known risk factor for BRONJ, and such intervention is often performed to eliminate existing pathological inflammatory conditions. Previously, we determined that ligature-induced periodontitis (LIP) is a risk factor for the development of osteonecrosis in mice, but it remains unclear whether the chronicity of LIP followed by extraction influences osteonecrosis development. In this study, we assess the effect of short-term and long-term LIP (ligature placed for 3 weeks [S-LIP] or 10 weeks [L-LIP], respectively) on osteonecrosis development in mice receiving 250 μg/kg/week zoledronic acid (ZOL). When compared to S-LIP, L-LIP caused 70% (p ≤ 0.0014) more bone loss without altering microbe composition. In the presence of ZOL, bone loss mediated by LIP was prevented and bone necrosis was induced. When the ligated tooth was extracted, histologic hallmarks of osteonecrosis including empty lacunae and necrotic bone were increased by 88% (p = 0.0374) and 114% (p = 0.0457), respectively, in L-LIP compared to S-LIP. We also observed significant increases in serum platelet factor 4 (PF4) and macrophage inflammatory factor 1 γ (MIP1γ) in mice that received ZOL treatment and had tooth extractions compared to controls, which may be systemic markers of inflammation-associated osteonecrosis development. Additionally, CD3+ T cells were identified as the major immune population in both health and disease, and we observed a 116% (p = 0.0402) increase in CD3+IL23R+ T cells in L-LIP compared to S-LIP lesions following extraction. Taken together, our study reveals that extracting a periodontally compromised tooth increases the formation of necrotic bone compared to extracting a periodontally healthy tooth and that osteonecrosis may be associated with the duration of the preexisting pathological inflammatory conditions. © 2022 American Society for Bone and Mineral Research (ASBMR).

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

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

Guideline No. 422g: Menopause and Osteoporosis

OBJECTIVE

Provide strategies for improving the care of perimenopausal and postmenopausal women based on the most recent published evidence.

TARGET POPULATION

Perimenopausal and postmenopausal women.

BENEFITS, HARMS, AND COSTS

Target population will benefit from the most recent published scientific evidence provided via the information from their health care provider. No harms or costs are involved with this information since women will have the opportunity to choose among the different therapeutic options for the management of the symptoms and morbidities associated with menopause, including the option to choose no treatment.

EVIDENCE

Databases consulted were PubMed, MEDLINE, and the Cochrane Library for the years 2002-2020, and MeSH search terms were specific for each topic developed through the 7 chapters.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations). INTENDED AUDIENCE: physicians, including gynaecologists, obstetricians, family physicians, internists, emergency medicine specialists; nurses, including registered nurses and nurse practitioners; pharmacists; medical trainees, including medical students, residents, fellows; and other providers of health care for the target population.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Oral Complications in Cancer Patients–Medication-Related Osteonecrosis of the Jaw (MRONJ)

Medication-Related Osteonecrosis of the Jaw (MRONJ) was first reported in 2003. Despite the progress in the understanding of this oral complication in cancer patients for the past 18 years, there is still discussion about the best way to define MRONJ, prevent the complication, how to diagnose, and the options of treatment available. The initial reports associated MRONJ to bisphosphonates and denosumab, medications that work as bone-modifying agents. Later, other agents such as the antiangiogenics, have also been reported to cause the oral complication, either alone or in combination with antiresorptives. Initially, these medications were prescribed to patients with osteoporosis and cancers patients with bone metastasis. Today, because of the effect of the medications in the bone remodeling system, patients with several other diseases such as giant cell tumors, rheumatoid arthritis, Paget's disease of bone, fibrous dysplasia, osteogenesis imperfecta, are managed with these medications, significantly increasing the population of individuals at risk for developing MRONJ. This mini review focused on the cancer patient. It updates the dental clinician on the recent scientific literature about MRONJ and provides information on how to diagnose and manage patients being treated with these medications, suggests protocols to prevent the development of MRONJ, and present ways to manage those patients who develop the oral complication.

Osteonecrosis of the Jaw and Antiresorptive Agents in Benign and Malignant Diseases: A Critical Review Organized by the ECTS

CONTEXT

Antiresorptive therapy significantly reduces fracture risk in patients with benign bone disease and skeletal-related events (SREs) in patients with bone metastases (BM). Osteonecrosis of the jaw (ONJ) is a rare but severe condition manifested as necrotic bone lesion or lesions of the jaws. ONJ has been linked to the use of potent antiresorptive agents, termed medication-related ONJ (MRONJ).

OBJECTIVE

We aimed to identify the differences various aspects of MRONJ among distinct patient categories and provide recommendations on how to mitigate the risk and optimally manage MRONJ in each of them.

METHODS

A working group of the European Calcified Tissue Society (ECTS) and 2 experts performed an updated detailed review of existing literature on MRONJ incidence, characteristics, and treatment applied in bone diseases with variable severity of skeletal insult, ranging from osteoporosis to prevention of cancer treatment-induced bone loss and SREs in cancer patients with BM.

RESULTS

The risk for MRONJ is much higher in patients with advanced malignancies compared to those with benign bone diseases because of the higher doses and more frequent administration of antiresorptive agents in individuals with compromised general health, along with coadministration of other medications that predispose to MRONJ. The overall risk for MRONJ is considerably lower than the benefits in all categories of patients.

CONCLUSION

The risk for MRONJ largely depends on the underlying bone disease and the relevant antiresorptive regimen applied. Physicians and dentists should keep in mind that the benefits of antiresorptive therapy far outweigh the risk for MRONJ development.

Biodegradable magnesium implant enhances angiogenesis and alleviates medication-related osteonecrosis of the jaw in rats

Background

Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication associated with antiresorptive and antiangiogenic medications, of which impaired angiogenesis is a key pathological alteration. Since Magnesium (Mg)-based implants possess proangiogenic effects, we hypothesized that the biodegradable Mg implant could alleviate the development of MRONJ via enhancing angiogenesis.

Methods

MRONJ model was established and divided into the Veh ​+ ​Ti group (Vehicle-treated rat, with Titanium (Ti) implant), BP ​+ ​Ti group (Bisphosphonate (BP)-treated rat, with Ti implant), BP ​+ ​Mg group (BP-treated rat, with Mg implant), BP ​+ ​Mg ​+ ​SU5416 group (BP-treated rat, with Mg implant and vascular endothelial growth factor (VEGF) receptor-2 inhibitor), BP ​+ ​Mg ​+ ​BIBN group (BP-treated rat, with Mg implant and calcitonin gene-related peptide (CGRP) receptor antagonist), and BP ​+ ​Mg ​+ ​SU5416+BIBN group (BP-treated rat, with Mg implant and VEGF receptor-2 inhibitor and CGRP receptor antagonist). The occurrence of MRONJ, alveolar bone necrosis, new bone formation and vessel formation were assessed by histomorphometry, immunohistochemistry, and micro-CT analysis.

Results

Eight weeks after surgery, the BP ​+ ​Mg group had significantly reduced occurrence of MRONJ-like lesion and histological osteonecrosis, increased bone microstructural parameters, and increased expressions of VEGFA and CGRP, than the BP ​+ ​Ti group. By simultaneously blocking VEGF receptor-2 and CGRP receptor, the vessel volume and new bone formation in the BP ​+ ​Mg group were significantly decreased, meanwhile the occurrence of MRONJ-like lesion and histological bone necrosis were significantly increased.

Conclusion

Biodegradable Mg implant could alleviate the development of MRONJ-like lesion, possibly via upregulating VEGF- and CGRP-mediated angiogenesis. Mg-based implants have the translational potential to be developed as a novel internal fixation device for patients with the risk of MRONJ.

The Translational potential of this article

This work reports a biodegradable Mg implant which ameliorates the development of MRONJ-like lesions possibly due to its angiogenic property. Mg-based implants have the potential to be developed as a novel internal fixation device for patients at the risk of MRONJ.