Effectiveness of treatments for medication-related osteonecrosis of the jaw: A systematic review and meta-analysis

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.

Laser Devices and Autologous Platelet Concentrates in Prevention and Treatment of Medication-Related Osteonecrosis of the Jaws: A Systematic Review

Background and Objectives: Medication-related osteonecrosis of the jaws (MRONJ) is a disease that affects many patients taking anti-angiogenic and antiresorptive medicines. Since the pathogenetic mechanism is still partially unknown, preventive strategies, as well as treatment alternatives, are needed. Therefore, the aim of this research is to describe the main evidence from the last 10 years of clinical trials regarding the use of auxiliary devices such as autologous platelet concentrates (APCs) and laser, other than their effects against MRONJ disease onset or therapy. Advantages in the healing process and recurrence rates were also analyzed. Materials and Methods: A systematic search of the electronic databases of PubMed and Scopus was carried out. Data from the studies were analyzed, and the risk of bias was evaluated. Results: Nineteen studies between interventional studies, observational studies, and cohort studies have been considered in this review. Conclusions: Based on the studies included, the literature analysis shows that APCs could be a beneficial alternative in preventing and treating MRONJ. Laser technology, as a surgical tool or used on the antimicrobial photodynamic or photobiomodulation side, has been becoming increasingly popular in the last few years. The latest proposal concerning the combination of both auxiliary tools suggests interesting effects, but more studies should be conducted to evaluate eventual relapses and long-term consequences.

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.

Management of Medication-Related Osteonecrosis of the Jaw with Photobiomodulation and Minimal Surgical Intervention

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively common pathology occurring in around 5% of patients taking bisphosphate and other antiresorptive or anti-angiogenic medications. Despite the efforts, as of today there is still no consensus on its management. In this case report, the successful management of stage II MRONJ was performed for an eighty-three-year-old female patient suffering from pain and alteration in her normal oral functions (swallowing and phonation). The treatment consisted of three sessions of photobiomodulation therapy (PBM), followed by minimal surgical intervention and three other sessions of PBM. PBM was applied on the sites of osteonecrosis with the follow parameters: 4 J/cm²; a power of 50 mW; 8 mm applicator diameter; a continuous contact mode. Irradiation was performed on three points, including the vestibular, occlusal and lingual parts of each of the bone exposure areas. Each point was irradiated for 40 s, and, in total, nine points were made per session, and nine sessions were conducted. To assess the pain, a visual analogue scale was used in which zero represented no pain at all and ten represented the greatest pain. At the first session and before any intervention, the patient stated that her pain was 8 out of 10. At the end of the treatment, a significant reduction in VAS was noted (2/10) and, clinically, a healing of the soft tissue in the previously exposed bone was observed. This case report suggests that the combination of PBM with surgical intervention is promising in the management of MRONJ.

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.

Management of Tooth Extraction in Patients Taking Antiresorptive Drugs: An Evidence Mapping Review and Meta-Analysis

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a well-known severe adverse reaction of antiresorptive, antiangiogenic or targeted therapies, and usually occurs after tooth extraction. This review is aimed at determining the efficacy of any intervention of tooth extraction to reduce the risk of MRONJ in patients taking antiresorptive drugs, and present the distribution of evidence in these clinical questions.

METHODS

Primary studies and reviews were searched from nine databases (Medline, EMBase, Cochrane Library, Scopus, WOSCC, Inspec, KCI-KJD, SciELO and GIM) and two registers (ICTRP and ClinicalTrials.gov) to 30 November 2022. The risk of bias was assessed with the ROBIS tool in reviews, and the RoB 2 tool and ROBINS-I tool in primary studies. Data were extracted and then a meta-analysis was undertaken between primary studies where appropriate.

RESULTS

Fifteen primary studies and five reviews were included in this evidence mapping. One review was at low risk of bias, and one randomized controlled trial was at moderate risk, while the other eighteen studies were at high, serious or critical risk. Results of syntheses: (1) there was no significant risk difference found between drug holiday and drug continuation except for a subgroup in which drug continuation was supported in the reduced incidence proportion of MRONJ for over a 3-month follow-up; (2) the efficacy of the application of autologous platelet concentrates in tooth extraction was uncertain; (3) there was no significant difference found between different surgical techniques in any subgroup analysis; and (4) the risk difference with antibacterial prophylaxis versus control was -0.57, 95% CI -0.85 to -0.29.

CONCLUSIONS

There is limited evidence to demonstrate that a drug holiday is unnecessary (and may in fact be potentially harmful) in dental practice. Primary closure and antibacterial prophylaxis are recommended despite limited evidences. All evidence have been graded as either of a low or very low quality, and thus further high-quality randomized controlled trials are needed to answer this clinical question.

Reporting Criteria for Clinical Trials on Medication-Related Osteonecrosis of the Jaw (MRONJ): A Review and Recommendations

Medication-related osteonecrosis of the jaw (MRONJ) is a complication caused by anti-resorptive agents and anti-angiogenesis drugs. Since we wanted to write a protocol for a randomized clinical trial (RCT), we reviewed the literature for the essential information needed to estimate the size of the active patient population and measure the effects of therapeutics. At the same time, we designed a questionnaire intended for clinicians to collect detailed information about their practices. Twelve essential criteria and seven additional items were identified and compiled from 43 selected articles. Some of these criteria were incorporated in the questionnaire coupled with data on clinical practices. Our review found extensive missing data and a lack of consensus. For example, the success rate often combined MRONJ stages, diseases, and drug treatments. The occurrence date and evaluation methods were not harmonized or quantitative enough. The primary and secondary endpoints, failure definition, and date coupled to bone measurements were not well established. This information is critical for writing a RCT protocol. With this review article, we aim to encourage authors to contribute all their findings in the field to bridge the current knowledge gap and provide a stronger database for the coming years.

Complementarity of surgical therapy, photobiomodulation, A-PRF and L-PRF for management of medication-related osteonecrosis of the jaw (MRONJ): an animal study

Background

This study aimed to evaluate the complementarity of surgical therapy, photobiomodulation (PBM), advanced platelet-rich fibrin (A-PRF), and Leukocyte and platelet-rich fibrin (L-PRF) for the management of medication-related osteonecrosis of the jaw (MRONJ).

Methods

Sixty rats underwent injection of zoledronate followed by left mandibular first and second molar extractions to induce MRONJ lesions. All rats were examined for the signs of MRONJ 8 weeks post-dental extraction. Forty-nine rats with positive signs of MRONJ were appointed to seven different groups as follows: control (Ctrl); surgery alone (Surg); surgery and PBM (Surg + PBM); surgery and A-PRF insertion (Surg + APRF); surgery and L-PRF insertion (Surg + LPRF); surgery, A-PRF insertion, and PBM (Surg + APRF + PBM); surgery, L-PRF insertion, and PBM (Surg + LPRF + PBM). Euthanasia was carried out 30 days after the last treatment session. The lesions' healing was evaluated clinically, histologically, and radiographically. Data were analyzed using STATA software version 14, and the statistical significance level was set at 5% for all cases.

Results

According to the present study, A-PRF and L-PRF treatment resulted in significant improvements in clinical, histological, and radiographical parameters compared to the Ctrl group (P < 0.05). The PBM also decreased wound dimensions and the number of empty lacunae compared to the Ctrl group (P < 0.05). Surg + APRF + PBM and Surg + LPRF + PBM were the only groups that presented a significantly higher mean number of osteocytes (P < 0.05). No significant differences were observed between A-PRF and L-PRF treatment groups (P > 0.05).

Conclusions

Surgical resection followed by applying A-PRF or L-PRF reinforced by PBM showed optimal wound healing and bone regeneration in MRONJ lesions.

Impact of acceleration on bone depiction quality by ultrashort echo time magnetic resonance bone imaging sequences in medication-related osteonecrosis of the jaw

Objectives

To assess the impact on bone depiction quality by decreasing number of radial acquisitions (RA) of a UTE MR bone imaging sequence in MRONJ.

Material and methods

UTE MR bone imaging sequences using pointwise encoding time reduction with RA (PETRA) with 60’000, 30’000 and 10’000 RA were acquired in 16 patients with MRONJ and 16 healthy volunteers. Blinded readout sessions were performed by two radiologists. Qualitative analysis compared the detection of osteolytic lesions and productive bony changes in the PETRA sequences of the patients with MRONJ. Quantitative analysis assessed the differences in image artifacts, contrast-to-noise ratio (CNR) and image noise.

Results

Acquisition times were reduced from 315 to 165 and 65 s (60’000, 30’000, 10’000 RA, respectively), resulting in a fewer number of severe motion artifacts. Bone delineation was increasingly blurred when reducing the number of RA but without any trade-off in terms of diagnostic performance. Interreader agreement for the detection of pathognomonic osteolysis was moderate (κ = 0.538) for 60’000 RA and decreased to fair (κ = 0.227 and κ = 0.390) when comparing 30’000 and 10’000 RA, respectively. Image quality between sequences was comparable regarding CNR, image noise and artifact dimensions without significant differences (all P > 0.05).

Conclusions

UTE MR bone imaging sequences with a lower number of RA provide sufficient image quality for detecting osteolytic lesions and productive bony changes in MRONJ subjects at faster acquisition times compared to the respective standard UTE MR bone imaging sequence.

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Ultrashort echo time MRI can assess medication-related osteonecrosis of the jaw.

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Sequences with a lower number of radial acquisitions reduce scan times.

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Image quality for detecting bony changes remains sufficient.

Photodynamic therapy and photobiomodulation therapy in zoledronic acid-induced osteonecrosis in rats

BACKGROUND

This study investigated the effect of antimicrobial photodynamic therapy (PDT), using methylene blue (MBO) and photobiomodulation therapy (PT), on the alveolar bone of rats submitted to bisphosphonate-induced osteonecrosis of the maxillaries (OMB) model using zoledronic acid (ZA).

METHODS

Sixty rats divided into six groups were used: SALINE, PDT, ZA, ZA+PDT, ZA+PT, and ZA+MBO. Three weekly administrations (Days 0, 7, and 14) of ZA 0.20 mg/kg or saline solution were performed. After one month (Day 42), the exodontia of the left lower first molars were performed. An additional dose of ZA was administered at Day 49. PDT was performed on days 42, 45, 49, and 54. One month after exodontia (Day 70), the animals were euthanized to obtain samples for imaging and microscopic analysis. ANOVA/Bonferroni tests were used for statistical analysis.

RESULTS

The ZA+PDT group showed a significantly lower percentage of apoptotic osteocytes than the ZA group (p<0.001). The ZA+MBO, ZA+PT, and PDT groups significantly reduced the number of mononuclear cells compared to the ZA group (p<0.001). The ZA+PT and ZA+PDT groups showed a significant reduction in the number of CD 68+ (p<0.001) and CD3+ (p=0.002) cells compared to the ZA group. The number of cells expressing INF-y had a significant reduction in the groups co-treated with PT and PDT compared to the ZA group (p<0.001).

CONCLUSIONS

We conclude that PDT and PT attenuated the severity of OMB and the inflammatory process due to a reduction of macrophages, T lymphocytes, and cytokines that stimulate the activity of these cells.

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.

Non-Interventional Prospective Observational Study of Platelet Rich Fibrin as a Therapy Adjunctive in Patients with Medication-Related Osteonecrosis of the Jaw

BACKGROUND

Medication-related osteonecrosis (MRONJ) of the jaw is a severe and feared side effect of antiresorptive therapy in the oncological setting. With growing evidence that impaired angiogenesis may represent a key factor in pathogenesis, the aim of this study was to evaluate an autologous platelet concentrate as a possible additive in surgical therapy to optimize vascularization and, subsequently, resolution rates.

MATERIAL AND METHODS

A non-interventional, prospective, multicenter study was conducted, and all patients with stage I-III MRONJ, undergoing antiresorptive therapy for an oncological indication, were included. The necrosis was treated surgically without (study arm A) or with (arm B) the addition of an autologous platelet concentrate (platelet-rich fibrin, PRF).

RESULTS

After 5, 14, and 42 days postoperative, wound healing (primary outcome: mucosal integrity) as well as downstaging, pain perception, and oral health-related quality of life (secondary outcome) were assessed via clinical evaluation. Among the 52 patients included, primarily with MRONJ stage I and II, the use of PRF as an additive in surgical therapy did not display a significant advantage for wound healing (p = 0.302), downstaging (p = 0.9), pain reduction (p = 0.169), or quality of life (p = 0.9).

SUMMARY

In conclusion, PRF as an adjunct did not significantly optimize wound healing. Further, no significant changes in terms of downstaging, pain sensation, and oral health-related quality of life were found.

Development and evaluation of the clinimetric properties of the Medication-Related Osteonecrosis of the Jaw Quality of Life Questionnaire (MRONJ-QoL)

The purpose of this study was to develop a self-administered questionnaire (MRONJ-QoL) to assess the quality of life (QoL) of patients with medication-related osteonecrosis of the jaw (MRONJ). A prospective study was performed to develop and evaluate the questionnaire. The MRONJ-QoL was formulated through a review of the literature and interviews of experts and patients. Following development, it was administered to 60 patients with a diagnosis of MRONJ. The sensibility of the questionnaire was assessed by evaluating feasibility (via interviews of patients), face validity (via interviews of patients and experts), and content validity (via evaluation of internal consistency, floor/ceiling effects, and factor analysis). Reliability was evaluated by measuring intra-rater reliability. Construct validity of the questionnaire was evaluated by both cross-sectional and longitudinal comparisons, including comparing scores of the MRONJ-QoL to disease resolution at 6 months. The final MRONJ-QoL questionnaire consisted of 14 questions, demonstrating high internal consistency (Cronbach's alpha of 0.85) and good reliability (weighted kappa score of 0.65). At the 6-month follow-up, disease resolution was found to be significantly associated with improved MRONJ-QoL scores, suggesting validity of the questionnaire (P < 0.01). Therefore, this is a sensible, reliable, and valid questionnaire for evaluating the QoL of patients with MRONJ.

Promising results of surgical management of advanced medication related osteonecrosis of the jaws using adjunctive leukocyte and platelet rich fibrin

Background

Leukocyte- and platelet-rich fibrin (L-PRF) is an autologous matrix scaffold which regulates inflammation by stimulating cytokines and growth factors that are involved in the immune response. L-PRF is suggested as a viable adjunctive method to surgical interventions due to its advantages on tissue healing. This study aims to retrospectively evaluate the adjunctive role of L-PRF in surgically treated medication-related osteonecrosis of the jaws (MRONJ) patients.

Methods

Between January 2012 and December 2020, patients with AAOMS stage II and III MRONJ lesions, who were treated surgically with adjunctive use of L-PRF in the authors’ institution were enrolled. Surgical interventions consisted of either marginal resection or sequestrectomy with peripheral ostectomy (SPO) or curettage and L-PRF application. Medical records of these patients were retrospectively reviewed and healing was assessed according to certain parameters including mucosal closure and presence of infection, exposed bone, fistula or radiologic markers of disease progression for a minimum of 12 months.

Results

Thirteen patients (7 women and 6 men) with an average age of 72.4 years (± 10.61, range 54–84) were included in the study, nine of whom had AAOMS stage III and four stage II MRONJ. Three patients had a marginal resection, nine patients had sequestrectomy with peripheral ostectomy (SPO) and one patient underwent a curettage procedure. All marginal resection and six SPO patients showed complete healing while four patients, who had SPO or curettage experienced incomplete healing. Mean follow up was 20.1 ± 18.29 months.

Conclusion

The use of L-PRF may be a favorable adjunctive option in the treatment of MRONJ owing to its favorable effects on tissue repair, ease of application, minimally invasive and cost-effective character and autogenous nature.

Trial registration Retrospectively registered.

Medication-Related Osteonecrosis of the Jaw: A Critical Narrative Review

Background: Nearly two decades have passed since a paradoxical reaction in the orofacial region to some bone modifying agents and other drugs was recognized, namely medication-related osteonecrosis of the jaw (MRONJ). Purpose: The aim of this manuscript was to critically review published data on MRONJ to provide an update on key terminology, concepts, and current trends in terms of prevention and diagnosis. In addition, our objective was to examine and evaluate the therapeutic options available for MRONJ. Methods: The authors perused the most relevant literature relating to MRONJ through a search in textbooks and published articles included in several databases for the years 2003–2021. Results and conclusions: A comprehensive update of the current understanding of these matters was elaborated, addressing these topics and identifying relevant gaps of knowledge. This review describes our updated view of the previous thematic blocks, highlights our current clinical directions, and emphasizes controversial aspects and barriers that may lead to extending the accumulating body of evidence related to this severe treatment sequela.

Surgical vs conservative treatment of medication-related osteonecrosis of the jaw-A complex systematic review and meta-analysis

OBJECTIVE

The objective of this study was to compare the outcome of surgical and conservative treatment approaches for medication-related osteonecrosis of the jaw.

STUDY DESIGN

Publications in Medline, The Cochrane Library, EMBASE, and PubMed (non-indexed articles) and by Health Technology Assessment organizations were searched. Quality of evidence in primary studies were assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) and the level of bias in systematic reviews by a measurement tool to assess systematic reviews (AMSTAR).

RESULTS

Quality assessment identified 3 primary studies with moderate GRADE score. Moderate risk of bias was found in 7 systematic reviews and low risk of bias in 3. Nine studies were included in the meta-analysis, where 62.1% healing was reported after surgical treatment (144 of 232 included patients) and 28.8% healing was reported after conservative treatment (38 of 132 included patients). Moderate heterogeneity was found among the included studies (P = .02). The overall odds ratio for resolution of osteonecrosis after surgical versus conservative treatment was 1.25 (95% confidence interval, 0.24-2.26) and was not statistically significant.

CONCLUSION

Slightly better outcomes are reported after surgical treatment, in particular for advanced disease stages, but there is a lack of standardized treatment protocols and outcome measures. Overall, the quality of evidence is poor, and the majority of studies have a low evidence certainty rating and high risk of bias.

Review of Myeloma Therapies and Their Potential for Oral and Maxillofacial Side Effects

Simple Summary

Myeloma is a common cancer involving the bone marrow. Some of the medications used in the treatment of myeloma, including those that reduce the risk of bone fractures, can increase the chance of side effects occurring in the jawbone. The most serious complication in the jawbone is called medication-related osteonecrosis, meaning part of the jawbone dies. The aim of this review is to highlight some of the medications that are implicated and other risk factors that can contribute to osteonecrosis. Suggestions to prevent this complication from occurring are described. Conventional methods of treating established medication-related osteonecrosis of the jawbone are outlined as well as emerging new treatments.

Abstract

Myeloma is a common haematological malignancy in which adverse skeletal related events are frequently seen. Over recent years, treatment for myeloma has evolved leading to improved survival. Antiresorptive therapy is an important adjunct therapy to reduce the risk of bone fractures and to improve the quality of life for myeloma patients; however, this has the potential for unwanted side effects in the oral cavity and maxillofacial region. Osteonecrosis of the jaw related to antiresorptive medications and other myeloma therapies is not uncommon. This review serves to highlight the risk of osteonecrosis of the jaw for myeloma patients, with some suggestions for prevention and management.

Different Presentation and Outcomes in the Surgical Treatment of Advanced MRONJ in Oncological and Nononcological Patients Taking or Not Corticosteroid Therapy

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect caused by antiangiogenic antiresorptive drugs used to treat various oncological and non oncological diseases. The clinical and radiological characteristics of MRONJ depend on the type of causative drug, the time of administration, and its dosage. 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 MRONJ. The risk factors themselves can affect treatment outcomes. Although the main scientific societies have recently disseminated good practice rules on the patient's prevention, diagnosis, and management, there are still no guidelines on shared therapeutic strategies. In general, if conservative treatment fails, surgical treatment is considered, including local debridement, osteoplasty, and marginal or segmental osteotomy. In literature, cohorts of heterogeneous patients with MRONJ have been analyzed for a long time, resulting in a lack of uniformity of information and difficulties interpreting the data. According to the American Association of Oral and Maxillofacial Surgeons criteria, this retrospective study evaluates the surgical treatment outcomes of 64 patients with stage II-III MRONJ, evaluated at the Department of Maxillofacial Surgery of the University of Turin (Italy). The first objective of this retrospective study is to evaluate treatment results for stages II-III in all cases; the second objective is to evaluate the same results by dividing the sample into different cohorts of patients: first, based on the underlying pathology, i.e., oncological and non oncological, and secondly, based on the drug or combination of drugs they took.

Treatment of Refractory Medicine Related Osteonecrosis of Jaw With Piezosurgical Debridement and Autologous Platelet Rich Fibrin: Feasibility Study

ABSTRACT

Medicine related osteonecrosis of jaw (MRONJ) is incidental in patients receiving certain bone modifying agents in oncology. These lesions may not respond to conservative management and aggravate. Autologous platelet derivatives contain bone growth factors, which help in bone regeneration. The aim of this pilot study is to develop protocol for treatment of refractory MRONJ with pizosurgical debridement and advanced platelet rich fibrin.In this feasibility study, refractory MRONJ lesions were treated by piezosurgical debridement and insertion of autologous advanced platelet rich fibrin in 15 patients. One patient had 2 lesion sites, so in all 16 MRONJ sites were treated. These patients were evaluated at the end of 1 month and 4 months for healing of MRONJ lesion. Statistical analysis was done by using Fisher test for response assessment in relation to variable. Eight lesions (50%) showed complete healing at the end of 1 month. At the end of 4 months 13 lesions (81.50%) were completely healed, 2 lesions (12.5%) were downgrades, and 1 lesion (6.25%) did not respond to treatment. Number of doses of bone modifying agent was only factor found associated with nonhealing of MRONJ when treated with this protocol.In this pilot study, feasibility of use of piezosurgical debridement and platelet rich fibrin was evaluated. The results of the study suggest complete healing can be achieved with this treatment protocol. Further research with increased sample size is warranted to determine optimum use of autologous platelet concentrates in treatment of MRONJ.

Various Therapeutic Methods for the Treatment of Medication-Related Osteonecrosis of the Jaw (MRONJ) and Their Limitations: A Narrative Review on New Molecular and Cellular Therapeutic Approaches

Medication-related osteonecrosis of the jaw (MRONJ) is one of the most interesting diseases in the field of maxillofacial surgery. In addition to bisphosphonates, the use of antiresorptive and antiangiogenic agents is known to be the leading cause. However, the exact pathogenesis of MRONJ has not been established, and various hypotheses have been proposed, such as oxidative stress-related theory. As a result, a definitive treatment protocol for MRONJ has not been identified, while various therapeutic approaches are applied to manage patients with MRONJ. Although the surgical approach to treat osteomyelitis of the jaw has been proven to be most effective, there are limitations, such as recurrence and delayed healing. Many studies and clinical trials are being conducted to develop another effective therapeutic modality. The use of some materials, including platelet concentrates and bone morphogenetic proteins, showed a positive effect on MRONJ. Among them, teriparatide is currently the most promising material, and it has shown encouraging results when applied to patients with MRONJ. Furthermore, cell therapy using mesenchymal stem cells showed promising results, and it can be the new therapeutic approach for the treatment of MRONJ. This review presents various treatment methods for MRONJ and their limitations while investigating newly developed and researched molecular and cellular therapeutic approaches along with a literature review.

Conservative Management of Medication-Related Osteonecrosis of the Jaws (MRONJ): A Retrospective Cohort Study

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of bisphosphonates and anti-resorptive drugs prescribed for treatment of severe osteoporosis, Paget's disease, and bone malignancies. The aim of this study was to evaluate the clinical outcome of a combined pharmacological and surgical management strategy on patients affected by MRONJ.

MATERIALS AND METHODS

Medical records of patients with MRONJ were retrospectively examined to collect clinical history data. Conservative management included an initial pharmacological phase with antibiotics and antiseptic agents, followed by surgical intervention to remove bone sequestrum. Primary outcomes were healing from MRONJ at short term (1 month after surgery) and at longer term (3 months after surgery). Secondary outcome was assessment of recurrences at longer-term follow-up.

RESULTS

Thirty-five patients were included in the study with mean follow-up of 23.86 ± 18.14 months. Seven cases showed spontaneous exfoliation of necrotic bone during pharmacological therapy, which in one case did not require any further intervention. At 1-month posttreatment, 31 out of 35 (88.5%) patients showed complete healing. The 25 patients who were followed for at least 3 months revealed a healing rate of 92% (23/25). Recurrences occurred in 7 patients out 23 who showed the long-term healing, after a mean period of 7.29 ± 3.45 months. The prognostic score (University of Connecticut Osteonecrosis Numerical Scale-UCONNS) was significantly higher (p = 0.01) in patients with poor healing as compared to complete healing, both at 1 and 3 months posttreatment.

CONCLUSIONS

A MRONJ treatment approach based on a combined pharmacological and surgical treatment strategy showed a high rate of healing and few recurrences.

Adjuvant therapies for MRONJ: A systematic review

OBJECTIVE

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction caused by the use of antiresorptive antiangiogenic medication. Treating MRONJ is difficult and besides standard treatments, which are conservative medical and surgical approaches, there are some adjuvant therapies that might further stimulate healing. The aim of this systematic review is to compare outcome and effectiveness of currently available adjuvant therapies for MRONJ.

METHODS

This systematic review was conducted following the PRISMA guidelines. Articles focusing on mucosal healing in patients treated with an adjuvant therapy for MRONJ were selected and analysed. Inclusion was not limited to randomized controlled trials to present a complete review of the current literature.

RESULTS

A search was performed in Pubmed, Embase, Web of Science and Cochrane Central Register of Controlled Trials. Thirty articles out of 3297 were included. Laser ablation had a success of 60-95% for complete healing. The controlled trials of leukocyte- and platelet-rich-fibrine (LPRF) showed 60-100% success for the same outcome. Fluorescence guided surgery had a complete healing percentage of 85-90%.

CONCLUSIONS

The results suggest that laser ablation, LPRF and fluorescence guided surgery might have a potential in improving the healing process. Interpreting the results should however be done with great care and a critical point of view, as most articles had a medium to high risk of bias. More randomized controlled trials are necessary to define the most beneficial therapy protocols.

CLINICAL RELEVANCE

It seems that adjuvant surgical therapies for treating MRONJ are beneficial for mucosal healing, but there is only low scientific evidence.

Surgical Treatment of Medication-Related Osteonecrosis of the Jaw: A Retrospective Study

The purpose of this study was to confirm the success rate of surgical treatment of medication-related osteonecrosis of the jaw (MRONJ) in patients at a single institution (Association of Oral and Maxillofacial Surgery (AAOMS) stages 1, 2, or 3), and to identify the factors that influence treatment outcomes. As a result of analyzing the outcomes of treatment, surgical "success" was achieved in 93.97% (109) of cases, and "failure" was observed at 6.03% (7) cases. Analysis of patient factors that potentially affect treatment outcomes showed that zoledronate dose (p = 0.005) and the IV (intravenous) injection of drugs (p = 0.044) had significant negative impacts.

Management of Medication-Related Osteonecrosis of the Jaw (MRONJ) Using Leukocyte- and Platelet-Rich Fibrin (L-PRF) and Photobiomodulation: A Retrospective Study

Background. The aim of this study was to compare retrospectively the effect of three different treatment protocols on the healing outcome in patients with established medication-related osteonecrosis of the jaw (MRONJ). Methods. A total of 34 MRONJ patients were recruited from the Department database and were divided according to the treatment protocols in a study group (G1) and two control groups (G2 and G3). G1 was treated with antibiotic therapy, surgery, leukocyte- and platelet-rich fibrin (L-PRF), and photobiomodulation; G2 was treated with antibiotic therapy and surgery; G3 was treated with antibiotic therapy and photobiomodulation. Various clinical variables and treatment protocols were analyzed to determine their correlation with the healing outcome at three and six months of follow-up. Results. There was a significant association between the different treatment protocols and the outcomes at both three and six months follow-up (p = 0.001 and p = 0.002, respectively). No significant association was observed between the outcomes and MRONJ localization, MRONJ stage, duration of drug treatment, gender, diabetes, corticosteroid therapy, smoking habits, underlying disease, and history of chemotherapy at both three and six months follow-up. Conclusions. Our results show that the combination of antibiotic therapy, surgery, L-PRF, and photobiomodulation may effectively contribute to MRONJ management.

The effect of pamidronate delivery in bisphosphonate-naïve patients on neutrophil chemotaxis and oxidative burst

The pathogenesis of medication-related osteonecrosis of the jaw (MRONJ), a morbid condition associated with bisphosphonate administration, has not been fully elucidated. Recent research utilizing a murine model has revealed that the neutrophil becomes dysfunctional following exposure to bisphosphonates. Accordingly, the impairment of neutrophil function could play an important role in the pathogenesis of MRONJ via an infectious mechanism mediated by the suppression of the innate immune system. Currently, the existing human data are insufficient to substantiate this theory. To investigate, we isolated neutrophils from blood and oral rinse samples from bisphosphonate-naïve patients who were recently diagnosed with multiple myeloma both prior to and one month following their initial infusion of pamidronate, an intravenous bisphosphonate agent. Stimulated blood and oral neutrophil superoxide production and chemotactic capabilities were found to be impaired relative to baseline values. These results suggest that impaired neutrophil function may partially contribute to the aetiology underlying the pathophysiological processes linked to the development of MRONJ. Further, as the functional status of circulating neutrophils was reflected in the oral cavity where sampling can be accomplished in a non-invasive fashion, it is conceivable that neutrophil function could serve as a potential biomarker for MRONJ prognostication.

Medication-Related Osteonecrosis of the Jaw with Spontaneous Hemimaxilla Exfoliation: Report of a Case in Metastatic Renal Cancer Patient under Multidrug Therapy

Medication-related osteonecrosis of the jaw (MRONJ) is a well-recognized complication of drug therapies for bone metabolic disorders or cancer related to administration of antiresorptive (bisphosphonates and denosumab) and antiangiogenic drugs. This report describes an advanced and unusual case of stage III peri-implantitis-induced MRONJ involving the right upper jaw which was attempting to self-exfoliate. A 61-year-old male patient, rehabilitated with the placement of two implants when he was still healthy, was suffering from metastatic renal cancer previously treated with bevacizumab, interleukin-2, zoledronic acid, denosumab, cabozantinib and nivolumab. He had been under treatment of nonsurgical therapy over a year, based on antibiotic and antiseptic mouth rinse, without improvement of oral conditions. Surgical treatment consisted of massive sequestrectomy and complete surgical debridement of necrotic bone tissues. The specimen was sent for histopathologic analysis, which confirmed bone tissue necrosis with no evidence of metastatic disease. Two-month follow-up revealed a considerable life quality improvement. Although this complication is well known, the uniqueness of this case is given by its severity, related to the administration of multiple antiresorptive and antiangiogenic drugs, by the natural response of the oral cavity with the almost complete self-exfoliation of the massive necrotic zone. This case is emblematic in highlighting the controversies in the management of MRONJ, which certainly require effective collaboration of the multidisciplinary health care team that could improve patient safety and reduce the risk of developing MRONJ.

Pathogenesis and multidisciplinary management of medication-related osteonecrosis of the jaw

Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect of bone-modifying agents and inhibits angiogenesis agents. Although the pathogenesis of MRONJ is not entirely clear, multiple factors may be involved in specific microenvironments. The TGF-β1 signalling pathway may have a key role in the development of MRONJ. According to the clinical stage, multiple variables should be considered when selecting the most appropriate treatment. Therefore, the prevention and management of treatment of MRONJ should be conducted in patient-centred multidisciplinary team collaborative networks with oncologists, dentists and dental specialists. This would comprise a closed responsibility treatment loop with all benefits directed to the patient. Thus, in the present review, we aimed to summarise the pathogenesis, risk factors, imaging features, clinical staging, therapeutic methods, prevention and treatment strategies associated with MRONJ, which may provide a reference that can inform preventive strategies and improve the quality of life for patients in the future.

Weak evidence for the management of medication-related osteonecrosis of the jaw: An overview of systematic reviews and meta-analyses

BACKGROUND

Although several therapies are proposed for medication-related osteonecrosis of the jaw (MRONJ), to date there is no consensus or treatment protocol for MRONJ. This overview aims to summarize the available evidence on the management and outcomes of MRONJ.

METHODS

An electronic search without language or date restrictions occurred in five databases and gray literature for articles published until March 2020. This overview was performed according to the PICO format. The eligibility criteria comprised systematic reviews (RS) with or without meta-analyses that analyzed treatments outcomes for MRONJ. The methodological quality of each SR was evaluated using AMSTAR 2.

RESULTS

Fifteen studies published between 2014 and 2020 were included in this overview. The summary of the evidence showed that conservative treatment and low level laser therapy can yield favorable results for early stages of MRONJ whereas surgical treatment seems to be better for advanced stages. However, qualitative assessment of the SRs highlighted a global low level of quality.

CONCLUSIONS

There is weak evidence to support treatment protocols for MRONJ. Because of the low quality of the SRs, highlighted by this overview, no insightful therapeutic recommendations can be issued for any intervention for MRONJ.

Can Surgical Management Improve Resolution of Medication-Related Osteonecrosis of the Jaw at Early Stages? A Prospective Cohort Study

PURPOSE

There is no clarity on which protocol is proper to use in the management of medication-related osteonecrosis of the jaw (MRONJ) at early stages (ie, stages 1 and 2) to halt disease progression. The aim of this study was to evaluate the success of surgical treatment in terms of time to mucosal integrity and downstaging in patients with MRONJ at early stages.

MATERIALS AND METHODS

The study was implemented as a prospective, single-center cohort study. The sample included patients who presented at Magna Graecia University of Catanzaro with a clinical diagnosis of MRONJ and underwent surgical treatment. The primary predictor variables were gender, age, medical history, drug administration, MRONJ localization, trigger factors, and stage. The outcome variables were 1) time to mucosal integrity after surgery with time-to-event analysis and 2) time to downstaging of MRONJ lesions. Descriptive, bivariate, and regression statistics were performed.

RESULTS

The study sample included 129 MRONJ patients (90 women and 39 men; mean age, 71.2 ± 12.7 years), of whom 57 had stage 1 and 72 had stage 2. The mean time to achieve mucosal integrity was 71.6 ± 67.7 days, considering the survival probability always to be 93% or greater. The mean time to achieve downstaging of the lesion was 43.6 ± 38.4 days. Patients older than 70 years, those affected by osteometabolic disorders, and those treated with oral antiresorptive therapy showed a significantly shorter time to mucosal healing and downstaging (P < .05). In patients with stage 2 MRONJ, we recorded a significantly longer time to mucosal integrity (56.4 ± 54.5 days) but shorter time to lesion downstaging (33.6 ± 9.9 days) than in patients with stage 1 MRONJ (P < .05).

CONCLUSIONS

Surgical treatment of patients in the early stages of MRONJ guarantees benefits in outcomes such as mucosal integrity and lesion downstaging, improvement in quality of life, and faster reuptake of medication therapy, especially for oncologic patients.

Antimicrobial photodynamic and photobiomodulation adjuvant therapies for prevention and treatment of medication-related osteonecrosis of the jaws: Case series and long-term follow-up

BACKGROUND

Medication-Related Osteonecrosis of the Jaws (MRONJ) incidence are increasing among elderly. Treatment can be challenging. Prevent or treatment protocols that control evolution of the lesion are warranted.

OBJECTIVE

To observe long-term outcomes of two protocols based on photonics [antimicrobial photodynamic therapy (aPDT) and photobiomodulation (PBM)] for prevention and treatment of MRONJ lesions.

METHODS

In a prospective study, patients who needed oral surgery and had been exposed to antiresorptive drugs were long-term followed-up. For MRONJ prevention, immediately after tooth extraction aPDT was applied. For aPDT a 0.01 % methylene blue solution was applied inside socket for 5 min followed by irradiation with a diode laser [660 nm, 0.028cm², 0.1 W, 3.57 W/cm², 90 s and 9 J per point, 321 J/cm², at least at in 3 points (laser probe was placed at central, and two equidistant points) and total energy of 27J]. Irradiation was repeated weekly until total tissue repair. MRONJ treatment included preoperative aPDT sessions until signs and symptoms of infection had reduced. Then, after necrotic bone removal, aPDT was applied inside surgical wounds and re-applied weekly until healing. Antibiotics were administered pre or postoperatively for no longer than 7 days. PBM therapy was applied with 808 nm diode laser, 0.028cm², 0.1 W, 3.57 W/cm², 30 s, 107 J/cm², 3 J and total energy of 12 J until evidence of remission.

RESULTS

Eighteen patients underwent preventive protocol, and none presented signs of MRONJ after a follow-up of at least 6 months. Seventeen patients presented with MRONJ underwent aPDT protocol and sixteen of them showed total regression of lesions.

PRACTICAL IMPLICATIONS

aPDT and PBM therapy protocols appear to be effective as adjuvant approach not only for preventing MRONJ development due to tooth extraction but for treating MRONJ lesions at early stages with no adverse effects.

Use of Platelet Rich Fibrin (PRF)-Based Autologous Membranes for Tooth Extraction in Patients under Bisphosphonate Therapy: A Case Report

Tooth extraction in patients treated with bisphosphonates (BPs) for osteoporosis or cancer exposes the patient to the risk of osteonecrosis of the jaw. An autologous membrane using platelet-rich fibrin (PRF) is an innovative technique to promote wound healing, which allows obtaining a hermetic closure of the post-extractive surgical site without the need of mucoperiosteal flaps or periosteal releasing incisions. Here, we report the case of a 70-year-old woman, in therapy with alendronate for 12 years, requiring the upper right premolar extraction because of a crown fracture. After the tooth extraction performed under antiseptic and antibiotic coverage, the PRF autologous membrane was placed on the surgical wound to close completely the post-extraction site. Follow-up visits were carried out after one, two, four weeks and two months from the intervention. The complete re-epithelization of the wound was observed without signs of infection. The use of PRF for the closure of post-extraction sockets in patients taking BPs appears to be a promising alternative to the more invasive surgical procedures. Future clinical trials will be pivotal in elucidating the effectiveness of PRF to prevent BP-related osteonecrosis after tooth extraction.

Medication-Related Osteonecrosis of the Jaw: MASCC/ISOO/ASCO Clinical Practice Guideline

PURPOSE

To provide guidance regarding best practices in the prevention and management of medication-related osteonecrosis of the jaw (MRONJ) in patients with cancer.

METHODS

Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) and ASCO convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations. Guideline development involved a systematic review of the literature and a formal consensus process. PubMed and EMBASE were searched for studies of the prevention and management of MRONJ related to bone-modifying agents (BMAs) for oncologic indications published between January 2009 and December 2017. Results from an earlier systematic review (2003 to 2008) were also included.

RESULTS

The systematic review identified 132 publications, only 10 of which were randomized controlled trials. Recommendations underwent two rounds of consensus voting.

RECOMMENDATIONS

Currently, MRONJ is defined by (1) current or previous treatment with a BMA or angiogenic inhibitor, (2) exposed bone or bone that can be probed through an intraoral or extraoral fistula in the maxillofacial region and that has persisted for longer than 8 weeks, and (3) no history of radiation therapy to the jaws or metastatic disease to the jaws. In patients who initiate a BMA, preventive care includes comprehensive dental assessments, discussion of modifiable risk factors, and avoidance of elective dentoalveolar surgery (ie, surgery that involves the teeth or contiguous alveolar bone) during BMA treatment. It remains uncertain whether BMAs should be discontinued before dentoalveolar surgery. Staging of MRONJ should be performed by a clinician with experience in the management of MRONJ. Conservative measures comprise the initial approach to MRONJ treatment. Ongoing collaboration among the dentist, dental specialist, and oncologist is essential to optimal patient care.

[Effect of zoladronate on the proliferation and osteogenic differentiation of rat bone mesenchymal stem cells]

OBJECTIVE

To evaluate the effect of zoledronate acid (ZA) on the proliferation and osteogenic differentiation of rat mesenchymal stem cells (BMSCs).

METHODS

The BMSCs isolated from the SD rats were cultured with different concentrations of ZA (1, 5, 10, and 20 μmol·L), and the contro1 group received the same volume of culture medium but without ZA. Cell counting kit-8 was used to detect proliferation activity in each group. Alkaline phosphatase (ALP) staining and alizarin red staining were used to detect the osteogenic differentiation ability in each group. The gene expression levels of ALP, bone morphogenetic protein-2 (BMP-2), typeⅠcollagenase (COL-Ⅰ), runt-related transcription factor-2 (Runx-2), zinc finger structure transcription factor (Osx), osteocalcin (OCN), and osteopontin (OPN) were evaluated by real-time quantitative polymerase chain reaction (qRT-PCR).

RESULTS

Zoledronate at 1 μmol·L⁻¹ concentration had no effect on the proliferation and osteogenic differentiation of BMSCs. No significant difference was observed between this group and the control group (P>0.05). When the ZA concentration was more than 1 μmol·L⁻¹, ZA inhibited the proliferation and osteogenic differentiation of BMSCs, and the effect was concentration dependent. The difference between each group and the control group was statistically significant (P<0.05). At ZA concentration of 5 μmol·L⁻¹, ZA enhanced the expression of ALP, BMP-2, COL-Ⅰ, Runx-2, Osx, OCN, and OPN (P<0.05). However, at ZA concentration of more than 5 μmol·L⁻¹, the expression levels of osteogenicrelated genes in each group was lower than those of the control group (P<0.05).

CONCLUSIONS

Low ZA concentration has no effect on the proliferation and osteogenic differentiation of BMSCs. ZA at 5 μmol·L⁻¹ concentration inhibits the proliferation but promotes the osteogenic differentiation of BMSCs. High ZA concentration inhibits the proliferation and osteogenic differentiation of BMSCs.

Rescue bisphosphonate treatment of alveolar bone improves extraction socket healing and reduces osteonecrosis in zoledronate-treated mice

Bisphosphonate (BP)-related osteonecrosis of the jaw, previously known as BRONJ, now referred to more broadly as medication-related osteonecrosis of the jaw (MRONJ), is a morbid condition that represents a significant risk for oncology patients who have received high dose intravenous (IV) infusion of a potent nitrogen containing BP (N-BP) drug. At present, no clinical procedure is available to prevent or effectively treat MRONJ. Although the pathophysiological basis is not yet fully understood, legacy adsorbed N-BP in jawbone has been proposed to be associated with BRONJ by one or more mechanisms. We hypothesized that removal of the pre-adsorbed N-BP drug common to these pathological mechanisms from alveolar bone could be an effective preventative/therapeutic strategy. This study demonstrates that fluorescently labeled BP pre-adsorbed on the surface of murine maxillo-cranial bone in vivo can be displaced by subsequent application of other BPs. We previously described rodent BRONJ models involving the combination of N-BP treatment such as zoledronate (ZOL) and dental initiating factors such as tooth extraction. We further refined our mouse model by using gel food during the first 7 days of the tooth extraction wound healing period, which decreased confounding food pellet impaction problems in the open boney socket. This refined mouse model does not manifest BRONJ-like severe jawbone exposure, but development of osteonecrosis around the extraction socket and chronic gingival inflammation are clearly exhibited. In this study, we examined the effect of benign BP displacement of legacy N-BP on tooth extraction wound healing in the in vivo model. Systemic IV administration of a low potency BP (lpBP: defined as inactive at 100 μM in a standard protein anti-prenylation assay) did not significantly attenuate jawbone osteonecrosis. We then developed an intra-oral formulation of lpBP, which when injected into the gingiva adjacent to the tooth prior to extraction, dramatically reduced the osteocyte necrosis area. Furthermore, the tooth extraction wound healing pattern was normalized, as evidenced by timely closure of oral soft tissue without epithelial hyperplasia, significantly reduced gingival inflammation and increased new bone filling in the extraction socket. Our results are consistent with the hypothesis that local application of a rescue BP prior to dental surgery can decrease the amount of a legacy N-BP drug in proximate jawbone surfaces below the threshold that promotes osteocyte necrosis. This observation should provide a conceptual basis for a novel strategy to improve socket healing in patients treated with BPs while preserving therapeutic benefit from anti-resorptive N-BP drug in vertebral and appendicular bones.

Bibliometric Analysis of Medication-Related Osteonecrosis of the Jaw: High Citation Rates but Low Evidence

PURPOSE

Citation analysis is one of the most commonly used bibliometric tools for measuring the academic importance of a report in a specific area of knowledge. The objective of the present study was to identify the 100 most cited reports on medication-related osteonecrosis of the jaw (MRONJ), determine their main bibliometric characteristics, and identify the bibliometric variables that affected the citation rates.

MATERIALS AND METHODS

We performed a data search in the Scopus database to determine the number of MRONJ article citations up to September 30, 2018. We next selected the 100 most referenced studies and recorded the following information: ranking according to the number of citations; citation density; number and names of authors; language and year of publication; country and institution of origin; financial support; journal name, impact factor, category, and quartile; type of research; evidence level; and area of study.

RESULTS

The 100 most cited reports had a mean citation density of 21.7 ± 20.7 (range, 6.2 to 99.4) and an h-index of 96. The 100 most cited reports on MRONJ had been published in 42 scientific journals, classified into 10 separate categories of the Journal Citation Reports; 56% of the articles were in the first quartile of their category. Most of the studies had been classified with a level of evidence of 4 (n = 45) or 5 (n = 29). In the bivariate analyses, only the conflict of interest (P = .002) was associated with citation density. After adjusting for numerous variables, conflict of interest (r = 0.27; P = .020) and country of the first author (r = 0.23; P = .043) were significantly associated with citation density.

CONCLUSIONS

The 100 most cited studies of MRONJ had a large number of citations and had been reported in journals with a high impact factor; however, the studies had a generally low evidence level and randomized clinical trials were lacking.

Surgical Management of Medication-Related Osteonecrosis of the Jaw Is Associated With Improved Disease Resolution: A Retrospective Cohort Study

PURPOSE

Optimal management approaches for medication-related osteonecrosis of the jaw (MRONJ) using either surgical or nonsurgical approaches remain inconclusive. Our objective was to compare the effects of surgical versus nonsurgical therapy on the resolution of MRONJ.

METHODS

We conducted a retrospective review of eligible patients with a diagnosis of MRONJ at Mount Sinai Hospital, Toronto, Ontario, Canada, who either were seen in the outpatient clinic from January 2014 to December 2016 or received major surgical intervention from January 2011 to December 2016. A multivariate logistic regression was conducted to evaluate the effects of surgical therapy on disease resolution.

RESULTS

A total of 78 patients were included in this study. Of these, 56 (72%) received surgical therapy. Antiresorptive agents were being taken for the treatment of osteoporosis by 46 patients (82%) in the surgical group compared with 20 nonsurgical patients (91%) (P = .28). The median follow-up period was 15.5 months (interquartile range, 8.0 to 34.3 months) in the surgical group compared with 11.0 months (interquartile range, 8.0 to 20.5 months) in the nonsurgical group (P = .75). Disease resolution occurred in 39 surgical patients (70%) compared with 8 nonsurgical patients (36%). Surgical therapy was associated with disease resolution compared with nonsurgical therapy alone, after adjustment for age, duration of antiresorptive or antiangiogenic therapy, whether the antiresorptive or antiangiogenic agents were used for oncologic purposes, and the stage of MRONJ at initial presentation (adjusted odds ratio, 4.33; 95% confidence interval, 1.28 to 14.60).

CONCLUSIONS

Surgical therapy compared with nonsurgical therapy was associated with disease resolution in patients with MRONJ. High-quality evidence of the superiority of any specific surgical approach in the treatment of MRONJ is needed.

Application of Autologous Platelet-Rich Plasma on Tooth Extraction Site Prevents Occurence of Medication-Related Osteonecrosis of the Jaws in Rats

This study evaluated the effects of local application of autologous platelet-rich plasma (PRP) on the tooth extraction site of rats presenting the main risk factors for medication-related osteonecrosis of the jaw (MRONJ). For seven weeks, senile rats were submitted to systemic treatment with vehicle (VEH and VEH-PRP) or 100 μg/Kg of zoledronate (ZOL and ZOL-PRP) every three days. After three weeks, the first lower molar was extracted. VEH-PRP and ZOL-PRP received PRP at the tooth extraction site. Euthanasia was performed at 28 days postoperatively. Clinical, histopathological, histometric and immunohistochemical analyses were carried out in histological sections from the tooth extraction site. ZOL showed lower percentage of newly formed bone tissue (NFBT), higher percentage of non-vital bone tissue (NVBT), as well as higher immunolabeling for TNFα and IL-1β. In addition, ZOL presented lower immunolabeling for PCNA, VEGF, BMP2/4, OCN and TRAP. VEH and ZOL-PRP showed improvement in the tooth extraction site wound healing and comparable percentage of NFBT, VEGF, BMP2/4 and OCN. Local application of autologous PRP proved a viable preventive therapy, which is safe and effective to restore tissue repair capacity of the tooth extraction site and prevent the occurrence of MRONJ following tooth extraction.

Is the conservative non-surgical management of medication-related osteonecrosis of the jaw an appropriate treatment option for early stages? A long-term single-center cohort study

PURPOSE

No consensus has been reached regarding the best treatment option for early-stage lesions in medication-related osteonecrosis of the jaw (MRONJ). The purpose of the present study was to evaluate the long-time outcomes of conservative non-surgical management in stage I patients with underlying malignant disease.

MATERIALS AND METHODS

We designed and implemented a retrospective cohort study and enrolled, between 2008 and 2018, a sample of patients with the indication for non-surgical conservative treatment stage I lesions. The primary outcome variable was treatment success defined as mucosal integrity without signs of infection. Secondary outcomes were: (i) worsening stage, (ii) necessity for surgical intervention over time, and (iii) discontinuation of antiresorptive therapy.

RESULTS

The sample included 75 patients with 92 lesions. Eight lesions showed full mucosal coverage, whereas 84 continued with exposed jaw bone (91.3%). Of the treatment-resistent 84 lesions, 67 presented a worsening stage shift over time. Indication for surgical intervention was set in 57 lesions. Of all lesions, 28 developed highly advanced necrotic bone destruction. Antiresorptive medication was paused in all evaluated patients after the first diagnosis of MRONJ.

CONCLUSION

Conservative non-surgical therapy in MRONJ stage I leads to a healing in rare cases. Conservative management might be a good option to preserve symptoms in patients either unwilling to undergo surgery or in those whose reduced general condition does not allow surgery. Early and consequent surgical advances should be performed throughout all stages of the disease to prevent the possibility of silent disease progression with the risk of large-scale bone loss.

Risk-reductive dental strategies for medication related osteonecrosis of the jaw among cancer patients: A systematic review with meta-analyses

The purpose of this systematic review with meta-analysis was to assess the effectiveness of dental interventions in preventing or reducing the incidence of medication-related osteonecrosis of the jaw (MRONJ) in cancer patients receiving antiresorptive therapy, compared to similar control groups receiving no intervention. Randomized controlled trials (RCT), case-controls and cohorts on cancer patients with primary outcome being the prevalence of MRONJ were included. Four electronic databases were searched (Cochrane Library, PubMed, EMBASE and Web of Science) up to February 12, 2018. A total of 409 abstracts were assessed and one case-control, one RCT and four cohort studies with 2332 cancer patients met our inclusion criteria. Risk of bias analysis followed Cochrane's handbook. Risk of bias was unclear for the case-control study and high risk for the RCT and all cohort studies. Five studies utilized preventive measures consisting of an initial examination and performing all necessary dental treatment before patients initiated antiresorptive therapy; one study used specialized post-extraction protocols utilizing plasma-rich in growth factors (PRGF) on cancer patients receiving antiresorptive therapy. Though dental preventive measures decreased MRONJ incidence by 77.3% in six studies with 2332 cancer patients (95% CI = 47.4-90.2%; p = .001) compared to control groups, quality of the evidence was low due to high or unclear risk of bias and the observational nature of five of the included studies. In conclusion, high-quality long-term prospective large sample size studies are needed to confirm these results due to high risk of bias and heterogeneous interventions. No funding.

Anabolic agents: what is beyond osteoporosis?

Osteoporosis is a common skeletal disorder characterized by low bone mass, which leads to reduced bone strength and an increased risk of fractures. Anabolic agents have been shown to improve bone mass and decrease fracture risk in osteoporosis patients by directly stimulating osteoblasts to produce new bone. Currently, two anabolic agents are available in the USA: recombinantly produced teriparatide (TPTD), which is the fully active (1-34) amino active sequence of human parathyroid hormone (PTH), and abaloparatide (APTD), a synthetic analog of parathyroid hormone-related peptide (PTHrP). At present, both agents are approved only for treatment of patients with osteoporosis at high risk of fracture. Nonetheless, their anabolic properties have led to off-label application in additional settings which include spine fusion, osteonecrosis of the jaw, arthroplasty, and fracture healing. In this article, we summarize available scientific literature regarding the efficacy, effectiveness, and safety of TPTD in these off-label settings.

A multicenter case registry study on medication-related osteonecrosis of the jaw in patients with advanced cancer

Purpose

This observational case registry study was designed to describe the natural history of cancer patients with medication-related osteonecrosis of the jaw (ONJ) and evaluate the ONJ resolution rate.

Methods

Adults with a diagnosis of cancer and with a new diagnosis of ONJ were enrolled and evaluated by a dental specialist at baseline and every 3 months for 2 years and then every 6 months for 3 years until death, consent withdrawal, or loss to follow-up. The primary endpoint was the rate and time course of ONJ resolution. Secondary endpoints included frequency of incident ONJ risk factors, ONJ treatment patterns, and treatment patterns of antiresorptive agents for subsequent ONJ.

Results

Overall, 327 patients were enrolled; 207 (63%) were continuing on study at data cutoff. Up to 69% of evaluable patients with ONJ had resolution or improvement during the study. ONJ resolution (AAOMS ONJ staging criteria) was observed in 114 patients (35%); median (interquartile range) time from ONJ onset to resolution was 7.3 (4.5–11.4) months. Most patients (97%) had received antiresorptive medication before ONJ development, 9 patients (3%) had not; 68% had received zoledronic acid, 38% had received denosumab, and 10% had received pamidronate (56% had received bisphosphonates only, 18% had received denosumab only, and 21% had exposure to both).

Conclusions

These results are consistent with those observed in clinical trials evaluating skeletal-related events in patients with advanced malignancy involving bone. Longer follow-up will provide further information on ONJ recurrence and resolution rates between medically and surgically managed patients.

Interventions for managing medication-related osteonecrosis of the jaw

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse reaction experienced by some individuals to certain medicines commonly used in the treatment of cancer and osteoporosis (e.g. bisphosphonates, denosumab and antiangiogenic agents) and involves the progressive destruction of bone in the mandible or maxilla. Depending on the drug, its dosage, and the duration of exposure, the occurrence of this adverse drug reaction may be rare (e.g. following the oral administration of bisphosphonate or denosumab treatments for osteoporosis, or antiangiogenic agent-targeted cancer treatment) or common (e.g. following intravenous bisphosphonate for cancer treatment). MRONJ is associated with significant morbidity, adversely affects quality of life (QoL), and is challenging to treat.

OBJECTIVES

To assess the effects of interventions versus no treatment, placebo, or an active control for the prophylaxis of MRONJ in people exposed to antiresorptive or antiangiogenic drugs.To assess the effects of non-surgical or surgical interventions (either singly or in combination) versus no treatment, placebo, or an active control for the treatment of people with manifest MRONJ.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 23 November 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 10), MEDLINE Ovid (1946 to 23 November 2016), and Embase Ovid (23 May 2016 to 23 November 2016). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on language or publication status when searching the electronic databases; however, the search of Embase was restricted to the last six months due to the Cochrane Embase Project to identify all clinical trials and add them to CENTRAL.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing one modality of intervention with another for the prevention or treatment of MRONJ. For 'prophylaxis of MRONJ', the primary outcome of interest was the incidence of MRONJ; secondary outcomes were QoL, time-to-event, and rate of complications and side effects of the intervention. For 'treatment of established MRONJ', the primary outcome of interest was healing of MRONJ; secondary outcomes were QoL, recurrence, and rate of complications and side effects of the intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, extracted the data, and assessed the risk of bias in the included studies. For dichotomous outcomes, we reported the risk ratio (RR) (or rate ratio) and 95% confidence intervals (CI).

MAIN RESULTS

We included five RCTs (1218 participants) in the review. Three trials focused on the prophylaxis of MRONJ. Two trials investigated options for the treatment of established MRONJ. The RCTs included only participants treated with bisphosphonates and, thus, did not cover the entire spectrum of medications associated with MRONJ. Prophylaxis of MRONJOne trial compared standard care with regular dental examinations in three-month intervals and preventive treatments (including antibiotics before dental extractions and the use of techniques for wound closure that avoid exposure and contamination of bone) in men with metastatic prostate cancer treated with zoledronic acid. The intervention seemed to lower the risk of MRONJ: RR 0.10; 95% CI 0.02 to 0.39 (253 participants; low-quality evidence). Secondary outcomes were not evaluated.As dentoalveolar surgery is considered a common predisposing event for developing MRONJ, one trial investigated the effect of plasma rich in growth factors (PRGF) for preventing MRONJ in people with cancer undergoing dental extractions. There was insufficient evidence to support or refute a benefit of PRGF on MRONJ incidence when compared with standard treatment (RR 0.08, 95% CI 0.00 to 1.51; 176 participants; very low-quality evidence). Secondary outcomes were not reported. In another trial comparing wound closure by primary intention with wound closure by secondary intention after dental extractions in people treated with oral bisphosphonates (700 participants), no cases of intraoperative complications or postoperative MRONJ were observed. QoL was not investigated. Treatment of MRONJOne trial analysed hyperbaric oxygen (HBO) treatment used in addition to standard care (antiseptic rinses, antibiotics, and surgery) compared with standard care alone. HBO in addition to standard care did not significantly improve healing from MRONJ compared with standard care alone (at last follow-up: RR 1.56; 95% CI 0.77 to 3.18; 46 participants included in the analysis; very low-quality evidence). QoL data were presented qualitatively as intragroup comparisons; hence, an effect estimate of treatment on QoL was not possible. Other secondary outcomes were not reported.The other RCT found no significant difference between autofluorescence- and tetracycline fluorescence-guided sequestrectomy for the surgical treatment of MRONJ at any timepoint (at one-year follow-up: RR 1.05; 95% CI 0.86 to 1.30; 34 participants included in the analysis; very low-quality evidence). Secondary outcomes were not reported.

AUTHORS' CONCLUSIONS

Prophylaxis of MRONJOne open-label RCT provided some evidence that dental examinations in three-month intervals and preventive treatments may be more effective than standard care for reducing the incidence of MRONJ in individuals taking intravenous bisphosphonates for advanced cancer. We assessed the certainty of the evidence to be low.There is insufficient evidence to either claim or refute a benefit of either of the interventions tested for prophylaxis of MRONJ (i.e. PRGF inserted into the postextraction alveolus during dental extractions, and wound closure by primary or secondary intention after dental extractions). Treatment of MRONJAvailable evidence is insufficient to either claim or refute a benefit for hyperbaric oxygen therapy as an adjunct to conventional therapy. There is also insufficient evidence to draw conclusions about autofluorescence-guided versus tetracycline fluorescence-guided bone surgery.