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

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.

[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.

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 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.

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.

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.

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.

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.

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.

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.

Elaborate the Mechanism of Ancient Classic Prescriptions (Erzhi Formula) in Reversing GIOP by Network Pharmacology Coupled with Zebrafish Verification

Osteoporosis is a degenerative disease that endangers human health. At present, chemical drugs used for osteoporosis have serious side effects. Therefore, it is valuable to search herbs with high safety and good curative effect in antiosteoporosis. Erzhi formula (EZF), an ancient classic compound, has been reported to have a beneficial effect in antiosteoporosis, but its mechanism is unclear. In this paper, the active compounds of EZF were found in Systems Pharmacology Database, and gene targets related to osteoporosis were obtained in GeneCards. The GO functional and KEGG pathway enrichment analysis were performed by Metascape. The network of “components-targets-signal pathway” was constructed by Cytoscape. Next, molecular docking between the active components and hub genes related to the PI3K-Akt signaling pathway was conducted by Autodock. In the verification experiment, the zebrafish induced by prednisolone (PNSL) was used to reproduce glucocorticoid-induced osteoporosis (GIOP) model, and then the reversal effects of EZF were systematically evaluated according to the behavior, skull staining area, bone mineralization area (BMA), average optical density (AOD), and cumulative optical density (COD). Finally, it was shown that 24 components in EZF could regulate 39 common gene targets to exert antiosteoporosis effect. Besides, the main regulatory mechanisms of EZF were 4 signaling pathways: PI3K-Akt, JAK-STAT, AGE-RAGE, and cancer pathway. In PI3K-Akt signaling pathway, wedelolactone, dimethyl wedelolactone, specnuezhenide, ursolic acid, acacetin, beta-sitosterol, apigenin, and kaempferol can bind tightly with EGF, IL-2, and IL-4 genes. Compared with the model group, the moving distance, swimming speed, and cumulative swimming time of zebrafish in EZF group were significantly increased (P < 0.05). Meanwhile, the BMA and COD of zebrafish were significantly improved after the intervention of EZF (P < 0.05). In summary, the 24 components of EZF exert their antiosteoporosis effects by regulating 39 related gene targets, among which the PI3K signaling pathway is crucial. EZF can promote bone formation and reversed GIOP through “multicomponent/multitarget/multipathway” and the medium dose of EZF may be the most suitable concentration for the treatment of GIOP in zebrafish model.

Non-antiresorptive drugs associated with the development of medication-related osteonecrosis of the jaw: a systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review was to provide evidence related to the association between non-antiresorptive medications and MRONJ.

MATERIALS AND METHODS

The following three electronic databases were screened: PubMed, EMBASE, and Web of Science from December 2020 until April 2021. Two reviewers independently performed the study selection, data extraction, and quality assessment of the included studies. The Newcastle-Ottawa Scale (NOS) was used for assessing the risk of bias. A meta-analysis was performed for assessing the relationship between MRONJ and non-antiresorptive medications.

RESULTS

The search strategy retrieved 996 articles. Following removal of duplicates, title, and abstract screening and full-text reading, 58 publications were eligible to be included in the review. A total of 867 cases of MRONJ were included (33% female, 55% male, 12% no gender reported). The mean age of the patients when MRONJ was diagnosed was 61 years (range 19-100 years) and the average time of diagnosis was 10 months following non-antiresorptive drug therapy. Patients with a history of corticosteroids (0.61, 95% CI 0.39, 0.82, p =  < 0.001) and chemotherapy (0.59, 95% CI 0.51, 0.67, p =  < 0.001) showed the highest significant effect size (ED) compared to the control group for MRONJ occurrence.

CONCLUSION

A significant association existed between MRONJ and non-antiresorptive drugs. However, considering limited evidence, findings should be interpreted with caution.

CLINICAL RELEVANCE

The non-antiresorptive drugs might allow the dentist to apply the principle of "drug holiday" following concurrence from the drug prescribing clinician.

PROSPERO REGISTRATION NUMBER

CRD42020173891.

Denosumab in the Treatment of Osteoporosis: 10 Years Later: A Narrative Review

The fully human monoclonal antibody denosumab was approved for treatment of osteoporosis in 2010 on the basis of its potent antiresorptive activity, which produces clinically meaningful increases in bone mineral density (BMD) and reduces fracture risk at key skeletal sites. At that time, questions remained regarding the long-term safety and efficacy of this receptor activator of nuclear factor kappa-B ligand (RANKL) inhibitor; and with clinical experience, new questions have arisen regarding its optimal use. Here, we examine these questions through the lens of data from the FREEDOM trial program and other studies to determine where denosumab fits in the osteoporosis treatment landscape. Clinical consensus and evidentiary support have grown for denosumab as a highly effective anti-osteoporosis therapy for patients at high risk of fracture. In the 10-year FREEDOM Extension study, denosumab treatment produced progressive incremental increases in BMD, sustained low rates of vertebral fracture, and further reduction in nonvertebral fracture risk without increased risk of infection, cancer, or immunogenicity. There was no evidence that suppression of bone turnover or mineralization was excessive, and rates of osteonecrosis of the jaw (ONJ) and atypical femoral fracture (AFF) were very low. It is now recognized, however, that transitioning to another anti-osteoporosis therapy after denosumab discontinuation is essential to mitigate a transient rebound of bone turnover causing rapid BMD loss and increased risk of multiple vertebral fractures (MVFs). Taken together, the available data show that denosumab has a favorable benefit/risk profile and is a versatile agent for preventing osteoporotic fractures in the short and long term.

An Interpretive Descriptive Approach to Understanding Osteoporosis Management from the Perspective of People at Risk of Fracturing

PURPOSE

Adherence to both non-pharmacological and pharmacological fracture prevention interventions is often low in people with osteoporosis. Understanding how patients acquire information about osteoporosis management is important for understanding both the initial decision-making and ongoing adherence. This study explored the narrative of people living with osteoporosis and their personal experience getting information about their osteoporosis management.

METHODS

An interpretive descriptive method was used for this qualitative study. In-depth interviews were conducted with 13 Canadian participants (age range 51-90) who knew that they had osteoporosis or osteopenia. Participants were asked to participate in one-on-one interviews to address the type of health professionals providing osteoporosis management advice focusing specifically on advice received about exercise, nutrition, and falls prevention. Interviews were transcribed verbatim and coded sentence-by-sentence.

RESULTS

People with osteoporosis rely on physicians for advice related to pharmacological treatment needs, and other health professionals for non-pharmacological needs such as exercise advice, nutrition advice, and falls prevention advice. People value non-professionals, such as family members and close friends, who may or may not have osteoporosis, to discuss or corroborate health professional advice, or to validate their belief system.

CONCLUSION

Training patients to more effectively engage in conversations with their healthcare providers may be a strategy to improve the quality of communication and its translation into adherence to best practices in managing osteoporosis.

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

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

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

[Bisphosphonate-related osteonecrosis of the jaws]

The number of patients with metabolic osteopathies and oncological diseases occurring with the formation of bone metastases is constantly growing and requires special attention not only of oncologists, but also maxillofacial surgeons, dental surgeons and periodontists, due to severe complications from the oral cavity, against the background of antiresorptive therapy with bisphosphonates. These drugs are associated with the development of necrotic processes of the jaw bones and surrounding tissues. It is worth noting the fact that the development of complications after taking these drugs leads to a significant increase in the suffering of patients. The importance of an integrated approach to the treatment and prevention of such complications is extremely important, as it reduces the risk of possible complications and improves the quality of life of this group of patients.

Prevalence, Incidence Rate, and Risk Factors of Medication-Related Osteonecrosis of the Jaw in Patients With Osteoporosis and Cancer: A Nationwide Population-Based Study in Japan

PURPOSE

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but severe adverse event of antiresorptive agents. However, the precise prevalence and factors associated with the development of MRONJ remain unknown. The present study was performed to describe the prevalence, incidence rate, and risk factors of developing MRONJ.

METHODS

We conducted a population-based retrospective cohort study using the National Database of Health Insurance, an administrative claims database of all patients in Japan. We identified patients who newly began using antiresorptive drugs from April 2015 to December 2018. The primary outcome was the development of MRONJ. We calculated the prevalence and incidence rate of MRONJ and performed a time-dependent Cox proportional hazard regression analysis to examine risk factors for developing MRONJ.

RESULTS

We identified 2,819,310 patients who newly used antiresorptive drugs during the study period. Of these patients, 2,664,104 (94.5%) had osteoporosis and 155,206 had cancer. Among the patients with osteoporosis, 1,603 (0.06%) developed MRONJ; the incidence rate was 22.9 per 100,000 person-years. Among the patients with cancer, 2,274 (1.47%) developed MRONJ; the incidence rate was 1,231.7 per 100,000 person-years. The occurrence of MRONJ was associated with poor oral conditions (including tooth extraction), age, male sex, drug type, concomitant drug use, comorbidities, cancer type, and geographic location.

CONCLUSIONS

The overall prevalence and incidence rate were low, but they were still higher than those in previous studies. Poor oral conditions were more closely related to the development of MRONJ than other factors. These findings suggest that improving poor oral hygiene may be essential to prevent MRONJ.

Medication-Related Osteonecrosis of the Jaw Subsequent to Peri-Implantitis: A Case Report and Literature Review

The aim of this report was to document a rare case of medication-related osteonecrosis of the jaw (MRONJ) that developed around the already osseointegrated implants in the maxillary right molar region. A 73-year-old woman presented at our university dental hospital in May 2017 with a chief complaint of discomfort near a maxillary implant. Her first visit was in 2006, and the maintenance treatment began in 2007 after the periodontal treatment. During the implant maintenance period there were no complications; however, the patient began taking alendronate sodium hydrate (Fosamac tablets, 35 mg, once weekly), an oral bisphosphonate (BP) since 2013, for treatment of osteoporosis. Eight years after starting implant maintenance, in 2016, peri-implantitis occurred, for which mechanical cleaning and antimicrobial therapy were performed. Peri-implantitis symptoms disappeared, and the medical condition improved. Nonetheless, in 2017, MRONJ developed 4 years after she commenced taking the BP. The patient underwent implant removal and sequestrectomy. There was no postoperative recurrence. Since it was such a rare case, we performed a literature review but only discovered a few similar cases. Because various triggers may lead to the development of MRONJ, even if already osseointegrated implant, it is important to note that implants in patients taking BPs should be more carefully maintained.

Osteonecrosis of the jaw: a rare but possible side effect in thyroid cancer patients treated with tyrosine-kinase inhibitors and bisphosphonates

Osteonecrosis of the jaw (ONJ) is a rare but very serious disease that can affect both jaws. It is defined as exposed bone in the maxillofacial region that does not heal within 8 weeks after a health care provider identification. ONJ can occur spontaneously or can be due to drugs like bisphosphonates (BPS) and anti-RANK agents, in patients with no history of external radiation therapy in the craniofacial region. Although in phase 3 trials of tyrosine kinase inhibitors (TKIs) used in thyroid cancer (TC) the ONJ was not reported among the most common side effects, several papers reported the association between ONJ and TKIs, both when they are used alone and in combination with a bisphosphonate. The appearance of an ONJ in a patient with metastatic radio-iodine refractory differentiated TC, treated with zoledronic acid and sorafenib, has put us in front of an important clinical challenge: when a ONJ occurred during TKIs treatment, it really worsens the patients' quality of life. We should consider that in the case of ONJ a TKI discontinuation becomes necessary, and this could lead to a progression of neoplastic disease. The most important aim of this review is to aware the endocrinologists/oncologists dealing with TC to pay attention to this possible side effect of BPS and TKIs, especially when they are used in association. To significantly reduced the risk of ONJ, both preventive measures before initiating not only antiresorptive therapy but also antiangiogenic agents, and regular dental examinations during the treatment should always be proposed.

Biologic and pathologic aspects of osteocytes in the setting of medication-related osteonecrosis of the jaw (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) is a potentially severe, debilitating condition affecting patients with cancer and patients with osteoporosis who have been treated with powerful antiresorptives (pARs) or angiogenesis inhibitors (AgIs). Oral risk factors associated with the development of MRONJ include tooth extraction and inflammatory dental disease (e.g., periodontitis, periapical infection). In bone tissues, osteocytes play a bidirectional role in which they not only act as the "receiver" of systemic signals from blood vessels, such as hormones and drugs, or local signals from the mineralized matrix as it is deformed, but they also play a critical role as "transmitter" of signals to the cells that execute bone modeling and remodeling (osteoclasts, osteoblasts and lining cells). When the survival capacity of osteocytes is overwhelmed, they can die. Osteocyte death has been associated with several pathological conditions. Whereas the causes and mechanisms of osteocyte death have been studied in conditions like osteonecrosis of the femoral head (ONFH), few studies of the causes and mechanisms of osteocyte death have been done in MRONJ. The three forms of cell death that affect most of the different cells in the body (apoptosis, autophagy, and necrosis) have been recognized in osteocytes. Notably, necroptosis, a form of regulated cell death with "a necrotic cell death phenotype," has also been identified as a form of cell death in osteocytes under certain pathologic conditions. Improving the understanding of osteocyte death in MRONJ may be critical for preventing disease and developing treatment approaches. In this review, we intend to provide insight into the biology of osteocytes, cell death, in general, and osteocyte death, in particular, and discuss hypothetical mechanisms involved in osteocyte death associated with MRONJ.

Is teriparatide therapy effective for medication-related osteonecrosis of the jaw? A systematic review and meta-analysis

Considering the lack of studies determining the real TPTD efficacy in individuals who develop MRONJ, our objective was to combine the available data on MRONJ cases treated with TPTD. The findings demonstrated that TPTD in combination with another therapy, especially antibiotic therapy, can be considered an effective protocol for MRONJ.

PURPOSE

To integrate the data published on the effect of teriparatide (TPTD) therapy on cases of medication-related osteonecrosis of the jaws (MRONJ) into a comprehensive analysis of clinical features.

METHODS

An electronic search was undertaken in six databases. Descriptive analyses of clinicodemographic data of MRONJ were carried out. Poisson regression was also run to evaluate predictors of total resolution of MRONJ treated with TPTD.

RESULTS

Twenty-six publications comprising 111 cases were included. Most reported cases affected female individuals (82.0%) with a mean age of 76.54 years. Osteoporosis (76.5%) represented the main reason for using antiresorptive drugs, with bisphosphonates (98.1%) as the most frequently reported. Comorbidities were commonly present. The most related trigger factor of MRONJ was dental extraction (61.7%). Mandible (75.8%) was the most commonly affected site, with a mean evolution time of 5 months. MRONJ stage 2 (61.3%) was the most prevalent. Regarding TPTD treatment, in 45.1% cases, TPTD was used alone, with the total resolution being observed in 59.5% of the individuals. Associated therapy (54.9%) included surgery, antibiotic therapy, and laser therapy. Mean follow-up was 8.7 months. Poisson regression demonstrated that individuals with MRONJ stage 1 were 1.21 times more likely to present total resolution of osteonecrosis than individuals with MRONJ stage 3 (CI = 1.02-1.43; p < 0.023). Individuals who had undergone treatment with TPTD in association with another therapeutic modality were 1.21 times more likely to present total resolution of osteonecrosis than those who had undergone treatment with TPTD alone (CI = 1.40-1.39; p < 0.010).

CONCLUSION

TPTD in combination with another therapy, especially antibiotic therapy, should be considered an effective therapeutic modality for MRONJ.