Oral bisphosphonate-related osteonecrosis of the jaws in rheumatoid arthritis patients: a critical discussion and two case reports

Possible association of methotrexate use with osteonecrosis of the jaw: Systematic review

The aim was to search systematically, evaluate, and then summarize scientific literature about possible methotrexate-associated osteonecrosis of the jaw (ONJ), its signs and symptoms, diagnosis, treatment, and prognosis in adults. After registration at PROSPERO this systematic review was conducted and reported according to the PRISMA checklist. The following databases were systematically searched: MEDLINE, EBSCO, The Cochrane Central Register of Controlled Trials (Central), SCIndex, Scopus, Google Scholar and Registry of clinical studies with human participants. In total 9 studies with 14 patients were included in the review. All cases of ONJ associated with methotrexate were described in patients suffering from Rheumatoid arthritis (RA), and only about 40% of them were taking other concomitant medication described to be associated with ONJ (bisphosphonates). Both sexes were equally affected, and the patients were rather old (over 60 years if age), already taking methotrexate for more than 12 years on average. Antibiotics were ineffective in the treatment of ONJ; after stopping methotrexate, all lesions healed after several months on average; however, half of the cases required covering of the exposed bone with mucosal flap. Recurrence of the methotrexate-associated ONJ was not observed for at least two years after the lesions were healed. Methotrexate-associated ONJ is serious clinical condition that may occur in patients with RA, but given the small number of cases we have found in the literature, direct involvement of methotrexate in the development of ONJ remains elusive.

Establishment and assessment of rodent models of medication-related osteonecrosis of the jaw (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) is primarily associated with administering antiresorptive or antiangiogenic drugs. Despite significant research on MRONJ, its pathogenesis and effective treatments are still not fully understood. Animal models can be used to simulate the pathophysiological features of MRONJ, serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of MRONJ. Rodent models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ, but classical methods cannot achieve a complete replica of the pathogenesis of MRONJ. Modified rodent models have been reported with improvements for better mimicking of MRONJ onset in clinic. This review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and efficiency. Currently, there is a lack of a unified assessment system for MRONJ models, which hinders a standard definition of MRONJ-like lesions in rodents. Therefore, this review comprehensively summarizes assessment systems based on published peer-review articles, including new approaches in gross observation, histological assessments, radiographic assessments, and serological assessments. This review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.

Occlusal Trauma and Bisphosphonate-Related Osteonecrosis of the Jaw in Mice

Osteonecrosis of the jaw (ONJ) is a serious adverse event that is associated with antiresorptive agents, and it manifests as bone exposure in the maxillofacial region. Previous clinical reports suggest that mechanical trauma would trigger ONJ in a manner that is similar to tooth extractions. To the best of our knowledge, there have been few detailed pathophysiological investigations of the mechanisms by which occlusal/mechanical trauma influences ONJ. Here, we developed a novel mouse model that exhibits ONJ following experimental hyperocclusion and nitrogen-containing bisphosphonate (N-BP) treatment. This in vivo model exhibited ONJ in alveolar bone, particularly in the mandible. Moreover, the experimental hyperocclusion induced remarkable alveolar bone resorption in both mouse mandible and maxilla, whereas N-BP treatment completely prevented alveolar bone resorption. In this study, we also modeled trauma by exposing clumps of mesenchymal stem cells (MSCs)/extracellular matrix complex to hydrostatic pressure in combination with N-BP. Hydrostatic pressure loading induced lactate dehydrogenase (LDH) release by calcified cell clumps that were differentiated from MSCs; this LDH release was enhanced by N-BP priming. These in vivo and in vitro models may contribute further insights into the effect of excessive mechanical loading on ONJ onset in patients with occlusal trauma.

The role of antiresorptive drugs and medication-related osteonecrosis of the jaw in nononcologic immunosuppressed patients: A systematic review

Medication related osteonecrosis of the jaw (MRONJ) is a severe condition affecting the jaws of patients exposed to specific drugs, and is primarily described in patients receiving bisphosphonate (BP) therapy. However, more recently it has been observed in patients taking other medications, such as the RANK ligand inhibitor (denosumab) and antiangiogenic drugs. It has been proposed that the existence of other concomitant medical conditions may increase the incidence of MRONJ. The primary aim of this research was to analyze all available evidence and evaluate the reported outcomes of osteonecrosis of the jaws (ONJ) due to antiresorptive drugs in immunosuppressed patients. A multi-database (PubMed, MEDLINE, EMBASE and CINAHL) systematic search was performed. The search generated twenty-seven studies eligible for the analysis. The total number of patients included in the analysis was two hundred and six. All patients were deemed to have some form of immunosuppression, with some patients having more than one disorder contributing to their immunosuppression. Within this cohort the commonest trigger for MRONJ was a dental extraction (n=197). MRONJ complications and recurrence after treatment was sparsely reported in the literature, however a total of fourteen cases were observed. The data reviewed have confirmed that an invasive procedure is the commonest trigger of MRONJ with relatively high frequency of post-operative complications or recurrence following management. However, due to low-quality research available in the literature it is difficult to draw a definitive conclusion on the outcomes analysed in this systematic review.

Simvastatin induces adverse effects on proliferation and mineralization of human primary osteoblasts

Background

Frequently statins were administered to reduce the LDL-concentration in circulating blood. Especially simvastatin (SV) is an often prescribed statin. Pleiotropic effects of these drugs were reported. Thus, the aim of this study was to evaluate effects of SV on osteoblastic mineralization.

Methods

After informed consent primary osteoblasts were collected from tissue surplus after treatment of 14 individuals in the Department of Cranio-Maxillofacial Surgery, University Hospital Münster. The cells were passaged according to established protocols. Viability, mineralization capability and osteoblastic marker (alkaline phosphatase) were determined at day 9, 13 and 16 after adding various SV concentrations (0.05 μM, 0.1 μM, 0.5 μM, 1.0 μM). Statistical analysis was performed using the Kruskal-Wallis-test.

Results

The cell cultures showed a time and dose-dependent significantly decreased viability (p < 0.01) and a significantly increased mineralization (p < 0.01) in a late mineralization stage after adding SV. The typical alteration of the alkaline phosphatase (ALP) levels during osteogenic differentiation was not recognizable.

Conclusions

The pleiotropic effects found for different SV concentrations were possibly originated from other mineralization pathways beside the ALP induced one. Additionally, possible alterations of protein expression levels during mineralization and investigation of possible deviating application of SV in other treatment fields can be considered after gaining a deeper insight in the affected mechanisms.

Clinical profile of individuals with bisphosphonate-related osteonecrosis of the jaw: an integrative review

BACKGROUND

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is still the most prevalent type of osteonecrosis with clinical relevance. In Brazil, bisphosphonate use is high but there is a lack of epidemiological studies on BRONJ.

OBJECTIVE

To determine the clinical profile of BRONJ in a Brazilian population through an integrative review.

DESIGN AND SETTING

Integrative review of BRONJ in a Brazilian population.

METHODS

Cases and clinical research on Brazilians with BRONJ between 2010 and 2019, indexed in PubMed/MEDLINE, Scopus, Web of Science and LILACS were reviewed. Age, sex, type and time of bisphosphonate intake, administration route, related diseases, region of the BRONJ, diagnostic criteria, staging, triggering factor and type of treatment were analyzed.

RESULTS

Fifteen articles on 128 subjects were included. Most patients were women (82.03%); the mean age was 63 years. Intravenous zoledronic acid was mostly used (62.50%), for breast cancer treatment (46.87%). The main localization of BRONJ was the mandible (54.68%), associated mainly with tooth extractions (45.98%). The diagnostic criteria were clinical (100%) and radiographic (89.06%), mostly in stage II (68.08%). The surgical treatments were sequestrectomy (37.50%) and platelet-rich plasma (PRP) (36.71%). Microbial control was done using chlorhexidine (93.75%) and infection control using clindamycin (53.90%).

CONCLUSIONS

BRONJ had higher prevalence in Brazilian women receiving treatment for breast cancer and osteoporosis. The mandible was the region most affected with a moderate stage of BRONJ, particularly when there were histories of tooth extraction and peri-implant surgery. Sequestrectomy with additional drugs and surgical therapy was the treatment most accomplished.

Sodium alendronate loaded poly(l-lactide- co-glycolide) microparticles immobilized on ceramic scaffolds for local treatment of bone defects

Bone tissue regeneration in critical-size defects is possible after implantation of a 3D scaffold and can be additionally enhanced once the scaffold is enriched with drugs or other factors supporting bone remodelling and healing. Sodium alendronate (Aln), a widely used anti-osteoporosis drug, exhibits strong inhibitory effect on bone resorption performed by osteoclasts. Thus, we propose a new approach for the treatment of bone defects in craniofacial region combining biocompatible titanium dioxide scaffolds and poly(l-lactide-co-glycolide) microparticles (MPs) loaded with Aln. The MPs were effectively attached to the surface of the scaffolds’ pore walls by human recombinant collagen. Drug release from the scaffolds was characterized by initial burst (24 ± 6% of the drug released within first 24 h) followed by a sustained release phase (on average 5 µg of Aln released per day from Day 3 to Day 18). In vitro tests evidenced that Aln at concentrations of 5 and 2.5 µg/ml was not cytotoxic for MG-63 osteoblast-like cells (viability between 81 ± 6% and 98 ± 3% of control), but it prevented RANKL-induced formation of osteoclast-like cells from macrophages derived from peripheral blood mononuclear cells, as shown by reduced fusion capability and decreased tartrate-resistant acid phosphatase 5b activity (56 ± 5% reduction in comparison to control after 8 days of culture). Results show that it is feasible to design the scaffolds providing required doses of Aln inhibiting osteoclastogenesis, reducing osteoclast activity, but not affecting osteoblast functions, which may be beneficial in the treatment of critical-size bone tissue defects.

Pathogenesis of medication-related osteonecrosis of the jaw: a comparative study of in vivo and in vitro trials

Objective This study was performed to determine whether the results of prevailing in vivo and in vitro studies offer a reliable model for investigation of medication-related osteonecrosis of the jaw (MRONJ). Methods Embase, Medline, and the Cochrane Library were searched for articles published from September 2003 to June 2017 involving experimental approaches to the pathogenesis of MRONJ. In vivo and in vitro trials were analyzed with respect to the scientific question, study design, methodology, and results. Results Of 139 studies, 87, 46, and 6 conducted in vivo, in vitro, and both in vivo and in vitro experiments, respectively. Rats, mice, dogs, minipigs, sheep, and rabbits were the preferred animal models used. Osteoblasts, osteoclasts, fibroblasts, keratinocytes, macrophages, and human umbilical vein endothelial cells were the preferred cell types. Zoledronate, alendronate, ibandronate, and risedronate were the most frequent bisphosphonates used. MRONJ was most reliably induced in minipigs because of the close relationship with human bone physiology. In vitro studies showed that reduced viability, growth, and migration of cells in the bone and soft tissues were causative for MRONJ. Other than exposed jawbone after tooth extraction, no reliable cofactors were found. Conclusion The minipig is the most suitable animal model for MRONJ.

Low-dose methotrexate in rheumatoid arthritis: a potential risk factor for bisphosphonate-induced osteonecrosis of the jaw

Bisphosphonate-induced osteonecrosis of the jaw [BIONJ] is a relatively new pathological condition which was first described in the year 2003. The prevalence of BIONJ in patients on oral formulations is around 0.05% within the first 3 years and increases up to 0.2% after 4 years of consumption. Proven systemic risk factors like anemia, uncontrolled diabetes, corticosteroid therapy, and chemotherapy in neoplastic diseases [e.g., high doses of methotrexate up to 30 mg daily] significantly increase the chances of acquiring BIONJ. We present three patients with osteoporosis and rheumatoid arthritis [RA] who consumed oral bisphosphonates [alendronate] for less than 1 year and developed BIONJ within 2 to 5 months of undergoing a traumatic dental procedure. The patients also gave a history of consuming low doses of methotrexate [disease-modifying anti-rheumatic drugs] up to 20 mg weekly for 4 to 10 years. No history of steroid consumption was given by any of the patients. This case series highlights the possibility of rheumatoid arthritis and low-dose methotrexate being potential risk factors for BIONJ. This may be on account of the synergistic effect of methotrexate and bisphosphonates and the pro-inflammatory state created by RA which increased the risk of acquiring BIONJ.

Skeletal complications of rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with local and systemic inflammation that induces many changes in the skeletal health. Locally, periarticular bone loss and juxta-articular bone erosions may occur while joint ankylosis, generalized bone loss, osteoporosis, and fractures may develop secondary to inflammation. The aim of this narrative review is to summarize the clinical evidence for abnormal skeletal health in RA, the effects of disease modifying anti-rheumatic drugs (DMARDS) on bone health, and the effects of drugs for the prevention or treatment of osteoporosis in the RA population.

Rheumatoid Arthritis Exacerbates the Severity of Osteonecrosis of the Jaws (ONJ) in Mice. A Randomized, Prospective, Controlled Animal Study

Rheumatoid arthritis (RA), an autoimmune inflammatory disorder, results in persistent synovitis with severe bone and cartilage destruction. Bisphosphonates (BPs) are often utilized in RA patients to reduce bone destruction and manage osteoporosis. However, BPs, especially at high doses, are associated with osteonecrosis of the jaw (ONJ). Here, utilizing previously published ONJ animal models, we are exploring interactions between RA and ONJ incidence and severity. DBA1/J mice were divided into four groups: control, zoledronic acid (ZA), collagen-induced arthritis (CIA), and CIA-ZA. Animals were pretreated with vehicle or ZA. Bovine collagen II emulsified in Freund's adjuvant was injected to induce arthritis (CIA) and the mandibular molar crowns were drilled to induce periapical disease. Vehicle or ZA treatment continued for 8 weeks. ONJ indices were measured by micro-CT (µCT) and histological examination of maxillae and mandibles. Arthritis development was assessed by visual scoring of paw swelling, and by µCT and histology of interphalangeal and knee joints. Maxillae and mandibles of control and CIA mice showed bone loss, periodontal ligament (PDL) space widening, lamina dura loss, and cortex thinning. ZA prevented these changes in both ZA and CIA-ZA groups. Epithelial to alveolar crest distance was increased in the control and CIA mice. This distance was preserved in ZA and CIA-ZA animals. Empty osteocytic lacunae and areas of osteonecrosis were present in ZA and CIA-ZA but more extensively in CIA-ZA animals, indicating more severe ONJ. CIA and CIA-ZA groups developed severe arthritis in the paws and knees. Interphalangeal and knee joints of CIA mice showed advanced bone destruction with cortical erosions and trabecular bone loss, and ZA treatment reduced these effects. Importantly, no osteonecrosis was noted adjacent to areas of articular inflammation in CIA-ZA mice. Our data suggest that ONJ burden was more pronounced in ZA treated CIA mice and that RA could be a risk factor for ONJ development. © 2016 American Society for Bone and Mineral Research.

Temporal correlation between bisphosphonate termination and symptom resolution in osteonecrosis of the jaw: a pooled case report analysis

PURPOSE

To investigate whether termination of bisphosphonates (BPs) affects resolution of bone exposure and symptomatic disease in patients with established medication-related osteonecrosis of the jaw (MRONJ).

PATIENTS AND METHODS

The studied population included 84 patients with established MRONJ who discontinued BP therapy before treatment (n = 21), at treatment initiation (n = 38), or later (or never) in the treatment course (n = 25). These 3 groups were compared using Kaplan-Meier curves and log-rank tests for differences in the respective times to resolution of 1) bone exposure for any treatment modality, 2) bone exposure not requiring radical surgery, and 3) disease symptoms.

RESULTS

Patients who continued BPs after the start of treatment exhibited significantly delayed resolution of symptoms (median 12 months; 95% confidence interval 8 to 15) compared with those who discontinued BPs before (3 months; 2 to 5) and at (6 months; 3 to 7) presentation (P < .005).

CONCLUSIONS

Independent of treatment modality and MRONJ stage at presentation, discontinuing BP before or at treatment initiation is associated with faster resolution of MRONJ symptoms compared with continuing the drug throughout jaw treatment. Patients should be counseled that continuing their BP medication after an established MRONJ diagnosis (compared to stopping the BP at diagnosis) may delay resolution of maxillofacial symptoms by approximately 6 months.

Bisphosphonate-associated osteonecrosis of jaw reoccurrence after methotrexate therapy: a case report

INTRODUCTION

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a well-known complication caused by amino-bisphosphonate therapy. We document one case of BRONJ associated with oral administration of methotrexate, a known immunosuppressive drug used to treat rheumatoid arthritis.

METHODS

A 66-year-old woman was referred for evaluation and endodontic surgery of recently re-treated tooth 13. Tooth 14 was extracted 3 months prior, and the extraction site had not completely healed. Her medical history revealed rheumatoid arthritis and osteoporosis. She had been taking Fosamax (alendronate) 70 mg daily. Because of adequate root canal therapy of tooth 13, endodontic surgery was performed. Five months after apicoectomy, her symptoms had not changed. Tooth 13 was extracted, and the socket healed without complications. The socket of extracted tooth 14 was also healing. At the 3-month recall visit, bone exposure and purulent discharge at the site of extracted tooth 14 were noted. The patient had recently received methotrexate. The methotrexate was discontinued, and she was given course of amoxicillin.

RESULTS

At the 18-month follow-up, the healing progressed, and the wound was closed.

CONCLUSIONS

A medication that suppresses the immune system such as methotrexate may complicate the management of BRONJ. Once a diagnosis of BRONJ is made, a closely monitored conservative approach is recommended.

Alendronate-associated osteonecrosis of the jaws: a review of the main topics

Bisphosphonates is a group of inorganic pyrophosphates analogues that suppress bone resorption by inducing osteoclast inactivation, being frequently used for management of diseases affecting bone metabolism, bone metastases and bone tumors. However, since 2003 many cases describing the presence of necrotic bone exposures in the jaws have been described in patients receiving these drugs, what represent a significant complication of bisphosphonates treatment. The overall incidence of bisphosphonate-related osteonecrosis of the jaws is low, ranging from 0.7% to 12%, mainly observed in those patients receiving intravenously treatment. Osteonecrosis of the jaws associated to oral bisphosphonate, particularly alendronate, has also been reported by a number of authors. Considering that alendronate is one of the most used drugs worldwide, specially for treatment of osteoporosis, a better understanding of osteonecrosis of the jaws related to its use and how to manage these patients is extremely important. Therefore, in the current manuscript the authors aim to review the most important topics related to this pathological presentation.

Key words:Bisphosphonates, alendronate, bisphosphonate-related osteonecrosis of the jaws, osteonecrosis.

Experimental development of bisphosphonate-related osteonecrosis of the jaws in rodents

Osteonecrosis of the jaw (ONJ) following the use of bisphosphonates has become of increased interest in the scientific community, due in particular to its as-yet-unsolved pathogenesis. An experimental model of ONJ was induced in normal male rats [alendronate (ALN); 1 mg/Kg/day; n = 10] and matched controls (saline solution; n = 10). After 60 days of drug treatment, all animals were subjected to extractions of the left first lower molars and were euthanized at 3 and 28 days postsurgery. The following analyses were performed: (i) descriptive and quantitative (scores) histological evaluation, (ii) stereometry of distal sockets and (iii) biochemical measurement of C-telopeptide cross-linked collagen type I (CTX) and bone-specific alkaline phosphatase (BALP). The results showed that 28 days postsurgery the animals treated with ALN had areas of exposed and necrotic bone, associated with significant infection, especially in the interalveolar septum area and crestal regions, compared with controls. The levels of CTX, BALP and bone volume, as well as the degrees of inflammation and vascularization, were significantly reduced in these animals. Therefore, analysis of the data presented suggests that ALN therapy is associated with the development of osteonecrosis in the jaws of rodents after tooth extraction.

Epidemiological aspects of rheumatoid arthritis patients affected by oral bisphosphonate-related osteonecrosis of the jaws

This literature review aims to evaluate the epidemiologic profile of patients with rheumatoid arthritis (RA) that developed a bisphosphonate-related osteonecrosis that affect the jaws (BRONJ), including demographic aspects, as well as clinical and therapeutic issues. A search of PUBMED/MEDLINE, Scopus, and Cochrane databases from January 2003 to September 2011 was conducted with the objective of identifying publications that contained case reports regarding oral BRONJ in RA patients. Patients with RA who develop oral BRONJ are usually women above 60 years taking steroids and long-term alendronate. Most of them have osteoporosis, and lesions, triggered by dental procedures, are usually detected at stage II in the mandible. Although there is no accepted treatment protocol, these patients seem to have better outcomes with conservative approaches that include antibiotic therapy, chlorhexidine, and drug discontinuation.

Bisphosphonate related osteonecrosis of the jaws: report of two cases

Bisphosphonates are compounds used to treat osteoporosis and malignant bone metastasis. Despite the benefits related to the use of these medications, osteonecrosis of the jaws is a significant complication in a subset of patients receiving these drugs. This complication occurs either spontaneously or after a simple dento-alveolar surgery. Recently there were two patients who showed the features of bisphosphonate related osteonecrosis of the jaws (BRONJ) in Gangneung-Wonju National University Dental Hospital. The patients revealed the clinical and radiological features of classical osteomyelitis. This report presents two cases of BRONJ which were examined by plain radiography and computed tomography.