Medication-related osteonecrosis of the jaw: Prevention, diagnosis and management in patients with cancer and bone metastases

Surgical extraction with photobiomodulation as an adjunctive modality in patients at-risk for medication-related osteonecrosis of the jaw: retrospective study

AIM

The study aims to retrospectively assess and share the experience of the use of photobiomodulation (PBM) as an adjunctive to surgical extraction in patients at-risk for medication-related osteonecrosis of the jaw (MRONJ) due to a treatment history with bone-modifying agents.

METHODS

The department database and medical records were examined in the period between 2016 and 2023. The inclusion criteria were; at-risk patients for MRONJ with current or previous treatment with bone-modifying agents, with or without a history of antiangiogenic agents administration, who underwent single or multiple dental extractions, subjected to PBM preventive protocol, and without a diagnosis or history of MRONJ development. The PBM protocol consisted of four sessions, two sessions before the intervention and two sessions after the intervention. The PBM parameters (per session) were; total power of 0.6 W, time of 15 min, frequency of 30 kHz, and total energy of 577.4 J.

RESULTS

A total of 62 patients (58 females and 4 males) fulfilled the inclusion criteria with a mean age of 67.5 years. Complete healing without the development of MRONJ was shown in 50 (80.65%) patients, and the development of MRONJ was shown in 12 (19.35%) patients. The statistical analysis revealed a higher risk of MRONJ in patients with a history of administration of zoledronic acid (p = 0.029) and in patients undergoing corticosteroid therapy (p = 0.039). While a lower risk was observed in patients in treatment for thyroid pathology (p = 0.055).

CONCLUSIONS

The majority of the included at-risk MRONJ patients showed complete healing after surgical extraction with the use of PBM as an adjunctive modality. Corticosteroid treatment as a systemic risk factor and zoledronic acid as a drug-related risk factor show significant associations with the development of MRONJ.

Nanomaterials-Based Drug Delivery Systems for Therapeutic Applications in Osteoporosis

The etiology of osteoporosis is rooted in the disruption of the intricate equilibrium between bone formation and bone resorption processes. Nevertheless, the conventional anti-osteoporotic medications and hormonal therapeutic regimens currently employed in clinical practice are associated with a multitude of adverse effects, thereby constraining their overall therapeutic efficacy and potential. Recently, nanomaterials have emerged as a promising alternative due to their minimal side effects, efficient drug delivery, and ability to enhance bone formation, aiding in restoring bone balance. This review delves into the fundamental principles of bone remodeling and the bone microenvironment, as well as current clinical treatment approaches for osteoporosis. It subsequently explores the research status of nanomaterial-based drug delivery systems for osteoporosis treatment, encompassing inorganic nanomaterials, organic nanomaterials, cell-mimicking carriers and exosomes mimics and emerging therapies targeting the osteoporosis microenvironment. Finally, the review discusses the potential of nanomedicine in treating osteoporosis and outlines the future trajectory of this burgeoning field. The aim is to provide a comprehensive reference for the application of nanomaterial-based drug delivery strategies in osteoporosis therapy, thereby fostering further advancements and innovations in this critical area of medical research.

Risk assessment and drug interruption guidelines for dentoalveolar surgery in patients with osteoporosis receiving anti-resorptive therapy

Medication-related osteonecrosis of the jaw (MRONJ) is a rare and challenging complication of anti-resorptive therapy. This review addresses the critical issue of risk management in patients with osteoporosis who require dentoalveolar surgery while undergoing anti-resorptive therapy. Dental practitioners should be aware of these risks; however, they should not refuse treatment based solely on them. This review discusses the risks through five major factors: invasive dentoalveolar surgeries, concomitant oral infection, type of medication, duration of medication, and preoperative drug discontinuation. Additionally, we discussed the local factors associated with dental practices. Our review underscored the importance of personalized risk assessment, considering each patient's unique drug history and oral condition. Based on a comprehensive literature review and clinical evidence, we proposed specific guidelines for preoperative drug interruption tailored to different anti-resorptive agents. These recommendations aimed to balance osteoporosis management by minimizing the risk of MRONJ during oral surgical interventions and bridging the knowledge gap in managing patients with osteoporosis requiring dental care. This review will allow clinicians to improve their practice and optimize patient outcomes by providing evidence-based strategies.

The role of a local application of 10% doxycycline gel in the prevention of medication-related osteonecrosis of the jaw in rats

OBJECTIVES

This study aimed to evaluate doxycycline on the prevention of MRONJ.

MATERIALS AND METHODS

Seventy-two Wistar rats were sorted into 3 groups and subjected to tooth extractions. The first group received systemic saline solution (SAL), the second received zoledronic acid (ZA), and the third, besides the systemic ZA, the post-extraction socket received local application of doxycycline (DOXI) gel. Samples were collected and analyzed at 7, 14, and 28 postoperative days.

RESULTS

DOXI group presented higher percentage of vital bone area as compared with ZA at 7 (p = 0.0058), 14 (p < 0.0001), and 28 days (p < 0.0001). TRAP immunolabeling was lower in ZA and DOXI at 7 and 14 days, while OCN immunolabeling was similar between the ZA and DOXI, except at 7 days. At 14 and 28 days, DOXI group presented more collagen type 3 and 1 (p < 0.0001) as compared with ZA. RUNX2, ALP, OCN, and RANKL gene expression was downregulated in ZA at 7 days. Conversely, DOXI upregulated these markers and OPG over time (p < 0.05).

CONCLUSION

Doxycycline is an effective local agent for preventing MRONJ, favoring alveolar bone healing.

CLINICAL RELEVANCE

Although widely studied, MRONJ remains a significant challenge in dentistry. The search for preventive methods is important to assure safety for in patients under antiresorptive therapy that demand surgical dental treatment. Doxycycline is well-established in dentistry, and the proposal of using this medication as a gel makes it more appealing since it is applied locally and has negligible adverse effects.

ONCOllab for Transmission of Knowledge Related to Oral Complications of Cancer Therapy Among Dental Students

INTRODUCTION

ONCOllab is a social media application developed by FDI to improve the management of oral complications that may arise during cancer therapy. This study aimed to evaluate the effects of ONCOllab on learning and perception among dental students.

MATERIAL AND METHOD

A theoretical test on oral complications of cancer therapy to determine baseline level knowledge was given to fourth-year dental students. Students were randomly divided into two groups. All students attended a lecture-based theoretical education on oral complications of cancer therapy. After the lecture, students were randomised into Group 1 (no further education) or Group 2 (presentation about ONCOllab with subsequent utilisation). One week later, a second test was applied to assess knowledge levels. The students' overall perception and satisfaction levels in Group 2 were also evaluated.

RESULTS

The study included 59 participants [female, 35 (59%)]. The results of the first evaluation test found similar baseline knowledge between the groups (p > 0.05). The second test's results were significantly higher in both groups (p < 0.05). However, students in the ONCOllab group (Group 2) showed a significantly higher level of knowledge than Group 1 for the second test scores (p = 0.001). All of the participants in the ONCOllab group found the application beneficial for education and reported that they would like to use it in the post-graduation period.

CONCLUSION

Both theoretical and ONCOllab-supported theoretical approaches significantly improved knowledge of oral complications of cancer therapy. However, in addition to educational superiority, ONCOllab-supported theoretical education was found to be associated with satisfactory results in terms of student perception.

Prevention of medication-related osteonecrosis of the jaw: institutional insights from a retrospective study

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a serious, debilitating condition of the jaw bones. Dental extraction is the most significant independent risk factor for MRONJ. This interim study aimed to evaluate the demographics, medical data and outcomes of patients at risk for MRONJ who underwent dental extractions in a dedicated MRONJ clinic following a risk reduction protocol at a large public dental clinic in New South Wales Health.

METHODS

A retrospective study analysed demographic and clinical data of patients at risk for MRONJ who underwent dental extractions between March 2020 and April 2024.

RESULTS

Data from 329 at-risk patients who underwent 836 dental extractions were included. Most patients were women (75.1%) with a median age of 74 years (IQR 67-80). The primary indication for medications was osteoporosis (85.4%), with Denosumab being the most frequently prescribed (66.9%). Eighteen patients (5.5%) developed MRONJ at 8 weeks of follow-up. Patients categorized as high-risk had a higher incidence of MRONJ (72.2%) compared to the low-risk group (22.2%).

CONCLUSION

This study is the first retrospective audit carried out after implementing preventive protocols in this dedicated MRONJ clinic. The higher incidence of MRONJ in patients classified as 'high risk' underscores the importance of considering individual risk factors in their treatment.

Novel standardized method for inducing medication-related osteonecrosis of the jaw in rats and precise quantitative assessment of pathological outcomes

Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication of antiresorptive therapies, characterized by delayed healing, bone necrosis, and infection following dental procedures. Progress in the understanding of its pathophysiology has been hindered by the lack of standardized animal models. Existing models involving first molar or multiple molar extractions disrupt anatomic landmarks and face technical challenges, such as retained root fragments and inconsistent surgical procedures, which reduce reproducibility. To address these limitations, we developed a novel rat MRONJ model using maxillary second molar extraction combined with standardized palatal gingiva resection. By preserving the adjacent first and third molars, anatomic landmarks were retained, enabling precise and reproducible evaluations. The modified extraction technique incorporating wedge insertion improved the success rate and minimized root fractures. Notably, our findings revealed that suppressed bone metabolism in the MRONJ model inhibited natural tooth movement observed in the control group, highlighting a unique pathologic hallmark of MRONJ. The model effectively reproduced MRONJ-specific features, including persistent bone exposure, impaired bone healing, necrotic bone formation, and inflammation. Three-dimensional micro-computed tomography and histologic analyses provided robust and quantitative assessments of bone pathology. By integrating anatomic standardization and precise quantitative assessments, this model addresses the key limitations of previous approaches. It also provides a reliable platform for investigating the pathogenesis of MRONJ and for assessing preventive and therapeutic strategies. This approach contributes to translational research and holds promise for improving clinical outcomes.

Antiresorptive therapy in combination with radiation results in enhanced risk for necrosis and associated complicatifions

OBJECTIVE

Patients exposed to a combination of antiresorptive medication and radiotherapy of the head and neck area developing necrosis of the jaw in the course of treatment are extremely rare. Therefore, the aim of this study was to identify the outcome and complications in this highly vulnerable patient cohort.

STUDY DESIGN

Seventeen patients who received both antiresorptive treatment and radiotherapy (medication-related osteonecrosis of the jaw/osteoradionecrosis = the [MRONJ/ORN] group) in the head and neck area were enrolled in this study. Included patients were treated in our department between 2005 and 2022. Four hundred twenty-four patients with MRONJ (the MRONJ group) and 138 patients with ORN of the jaw were enrolled as two control groups (the ORN group). Demographic data, lesion localization, date of primary diagnosis, clinical symptoms, type of therapy (surgical or non-surgical), details on antiresorptive treatment, outcome, and complications were recorded.

RESULTS

Pathological fractures, continuity resection, and recurrence appear more often in patients who receive a combination of antiresorptive treatment and radiotherapy in the head and neck area compared with patients undergoing only one of these treatments. There was a statistically significant difference (P < .001) between the MRONJ/ORN group and the MRONJ group and the MRONJ/ORN group and the ORN group considering recurrence, fracture, and continuity resection. Patients with ORN combined with MRONJ have a 4-times higher risk for developing recurrence compared with patients with MRONJ and a 1.5-times higher risk for recurrence compared with patients with ORN. Jaw fracture and continuity resection appear more often in patients with MRONJ/ORN.

CONCLUSIONS

Patients under antiresorptive therapy in combination with radiation therapy in the head and neck area have a higher risk for developing complications in case of osteonecrosis of the jaw. Therefore, a strict follow-up care schedule is highly recommended.

A multifaceted role of bisphosphonates from palliative care to anti-cancer therapy in solid tumors

INTRODUCTION

Bisphosphonates (P-C-Ps) also called diphosphonates are the structural analogs of naturally occurring pyrophosphates. Bisphosphonates are traditionally used and shown to provide long-term success in the treatment and prevention of osteoporosis and other bone loss pathologies. Furthermore, bisphosphonates are gaining popularity in the present era of cancer therapeutics and prevention. The usage of bisphosphonates as adjuvant or neoadjuvant therapy, either as a single agent or combined with other chemotherapy, has been studied in different solid tumors. This review aims to present the various roles of bisphosphonates in solid tumors.

DATA SOURCES

Articles in MEDLINE/PubMed and the National Institutes of Health Clinical Trials Registry (http://www. Clinicaltrials.gov) between 1 January 2011 and 1 February 2022 were extracted using MeSH terms "bisphosphonates/diphosphosphonates and mechanism," "bisphosphonates and breast cancer," "bisphosphonates and prostate cancer," "bisphosphonates and lung cancer," "bisphosphonates and cancer risk," and "bisphosphonates and adverse events." Manual searches of some major oncology journals were also conducted.

DISCUSSION

This review article focuses on the antitumor activity of bisphosphonates, safety profile, and the role of bisphosphonates as preventive, neoadjuvant, and adjuvant chemotherapy. A significant improvement in overall survival and cancer-specific survival and recurrence-free survival with the usage of bisphosphonates is noted in breast cancer patients, particularly in post-menopausal women. Though great progress has been achieved in over 20 years, further research is needed to identify the subgroup of patients that are most likely to benefit from adjuvant bisphosphonate therapy and to determine regimens with greater efficacy and better safety profile.

Management of Medication-Related Osteonecrosis of the Jaw: An Overview of National and International Guidelines

There is variability amongst clinicians in the management of medication-related osteonecrosis of the jaw (MRONJ) though numerous guidelines are available. The aim of this critical review is to appraise current international and national guidelines on MRONJ to evaluate areas of consensus or inconsistency, identify areas lacking evidence, and discuss recommendations with agreement and variability across guidelines. A literature search was performed to identify all national and international guidelines published until May 2022 on the prevention and treatment of MRONJ. Included guidelines were compared and critically appraised with Appraisal of Guidelines for Research and Evaluation II (AGREE II). The included sixteen guidelines were published from ten different countries, two of which had international collaborations. AGREE II assessment found four guidelines of high quality. There is consensus to optimise oral health prior to and during therapy, to conservatively manage established MRONJ in earlier stages and consider surgery at advanced stages. There is disparity on strategies to reduce the risk of osteonecrosis such as the avoidance of invasive dental procedures, therapy suspension, and techniques to reduce the impact of invasive surgery. The authors recommend an international lead in the development of dental guidelines to establish a global standardised management approach aiming for better health equality.

Risk factors of medication-related osteonecrosis of the jaw: A clinical investigation

Medication-related osteonecrosis of the jaw (MRONJ) is an intractable condition caused by drugs such as bisphosphonates and denosumab. This study investigated the changes in the incidence of MRONJ in the previous 10 years and examined the poor prognostic factors during surgery in at-risk patients. We compared 57 and 64 patients diagnosed with MRONJ at our hospital between January 2012 and December 2016 and January 2017 and December 2021, respectively. The disease stage and triggers at the time of initial diagnosis in eligible patients were investigated. Additionally, the adverse prognostic factors were examined in 166 patients at risk of MRONJ who underwent tooth extraction at our department during these 10 years. The results indicated that there was no change in the proportion of patients with osteoporosis and malignancy among those with MRONJ. The number of cases after tooth extraction decreased, and those after dental infections increased on comparing the recent 5 years and the preceding 5 years. The number of MRONJ patients receiving denosumab also increased. Denosumab was a significant post-extraction prognostic factor for delayed healing in the 166 patients at risk of MRONJ. The findings suggest that patients receiving denosumab should be closely monitored when undergoing surgery to prevent MRONJ.

Knowledge and Awareness of Medication-Related Osteonecrosis of the Jaw Among Dental Practitioners in Mumbai: A Questionnaire-Based Survey

INTRODUCTION

Osteonecrosis of the jaw resulting from the adverse effects of medical treatments is known as medication-related osteonecrosis of the jaws (MRONJ). The knowledge of dental professionals about this condition is crucial in addressing it on a regional and global scale. This study aims to assess the knowledge and awareness of MRONJ among dental practitioners in Mumbai.

MATERIALS AND METHODS

This descriptive cross-sectional study utilized a web-based questionnaire comprising 21 questions distributed to dental professionals and postgraduate students at dental colleges, hospitals, and private practices in Mumbai.

RESULTS

A total of 403 dentists participated in the survey, with 85% familiar with the condition. A significantly (p < 0.05) higher proportion of clinicians with over 20 years of experience and those specializing in oral and maxillofacial surgery were aware of the indications for bisphosphonate drugs. About 53% of oral surgeons and 57.7% of participants with more than 20 years of experience were aware that antiangiogenic drugs are used in breast cancer treatment. However, awareness of their use in lung cancer was only about 21%.

CONCLUSIONS

Although practitioners were familiar with the term MRONJ, their knowledge of the drugs affecting the disease, as well as its clinical and radiographic presentations, was inadequate. Awareness of treatment strategies and recent advances was particularly lacking among general dentists and other specialists apart from oral and maxillofacial surgeons (OMFS). Practitioners also identified a lack of an interdisciplinary approach. There is a clear need for enhanced education and awareness on this subject, which can be achieved by conducting interdisciplinary surveys, conferences, and seminars.

Education and Communication on the Topic of Osteonecrosis of the Jaw When Taking Bone-Stabilizing Drugs

OBJECTIVES

The aim of this study was to analyze the communication between doctors and patients who were taking bone-stabilizing medication and in rare cases developed osteonecrosis of the jaw as a result.

MATERIAL AND METHODS

A standardized questionnaire recorded deficits based on patient experiences. These data were used to develop solution strategies for improving doctor-patient communication and the benefit-risk assessment of medication use.

RESULTS

Most patients were satisfied with the information provided by their doctor; however, one in three (29.8%) were not informed about possible side effects, and a quarter (24.6%) only found out about osteonecrosis of the jaw through their own research. Only half (45.7%) were asked about risk factors, and most information materials were rated poorly. The diagnosis took an average of 18.7 months, with many (47.8%) consulting a doctor only when they experienced pain. Quality of life was severely impaired, with daily pain, physical limitations, and negative effects on mental health. About a third (35.3%) reported that their quality of life had deteriorated significantly.

CONCLUSIONS

Further research into patient education is necessary. Web-based information brochures, improved follow-up care, and close cooperation with dentists are required. The use of a running sheet, such as the AGSMO running sheet, for individual risk assessment of osteonecrosis of the jaw is recommended. Patients undergoing treatment with bone-stabilizing medication should be monitored closely. Education about osteonecrosis of the jaw must be continued, and the medical profession must be confronted with it.

Targeting endoplasmic reticulum stress-induced lymphatic dysfunction for mitigating bisphosphonate-related osteonecrosis

BACKGROUND

Bisphosphonates (BPs) are the first-line treatment to stop bone resorption in diseases, including osteoporosis, Paget's disease, multiple myeloma and bone metastases of cancer. However, BPs-related osteonecrosis of the jaw (BRONJ), characterized by local inflammation and jawbone necrosis, is a severe intractable complication. The cumulative inflammatory burden often accompanies impaired lymphatic drainage, but its specific impact on BRONJ and the underlying mechanisms remain unclear.

METHODS

The mouse BRONJ model was established to assess the integrity and drainage function of lymphatic vessels by tissue clearing techniques, injected indocyanine green lymphatic clearance assay, flow cytometry analysis and histopathological staining. RNA sequencing, metabolome analysis, transmission electron microscopy and Western blotting were utilized to analyze the impacts of Zoledronate acid (ZA) on endoplasmic reticulum stress (ERS) and function of lymphatic endothelial cells (LECs). By constructing Lyve1creERT; SIRT6f/f and Lyve1creERT; ATG5f/f mice, we evaluated the role of ERS-induced LECs apoptosis in the progression of BRONJ. Additionally, we developed a nanoparticle-loaded ZA and rapamycin (ZDPR) to enhance autophagy and evaluated its potential in mitigating BRONJ.

RESULTS

The mouse BRONJ model displayed impaired lymphatic drainage, accompanied by significant local inflammation and bone necrosis. The prolonged stimulation of ZA resulted in the extension of ERS and the inhibition of autophagy in LECs, ultimately leading to apoptosis. Mechanistically, ZA activated XBP1s through the NAD+/SIRT6 pathway, initiating ERS-induced apoptosis in LECs. The conditional knockout mouse models demonstrated that the deletion of SIRT6 or ATG5 significantly worsened lymphatic drainage and inflammatory infiltration in BRONJ. Additionally, the innovative nanoparticle ZDPR alleviated ERS-apoptosis in LECs and enhanced lymphatic function, facilitating inflammation resolution.

CONCLUSION

Our study has elucidated the role of the NAD+/SIRT6/XBP1s pathway in ERS-induced apoptosis in ZA-treated LECs, and further confirmed the therapeutic potential of ZDPR in restoring endothelial function and improving lymphatic drainage, thereby effectively mitigating BRONJ.

KEY POINTS

Bisphosphonate-induced lymphatic drainage impairment exacerbates bone necrosis. Zoledronate acid triggers endoplasmic reticulum stress and apoptosis in lymphatic endothelial cells via the NAD+/SIRT6/XBP1s pathway. Novel nanoparticle-loaded Zoledronate acid and rapamycin enhances autophagy, restores lymphatic function, and mitigates bisphosphonates-related osteonecrosis of the jaw progression.

Osteonecrosis of the jaw associated with ustekinumab in the treatment of Crohn's

MRONJ is a well-known side effect of antiresorptive and antiangiogenic drug treatment. Crohn's disease involves pro-inflammatory interleukins IL-12 and IL-23. Ustekinumab is a targeted therapy antagonist of the p40 subunit of IL-12 and -23 indicated in the treatment of immune-mediated inflammatory diseases. A 72-year-old man with Crohn's disease developed MRONJ after being treated with ustekinumab for four years. The patient presented with bone exposure three months after the extraction of two mandibular teeth. He had no known predisposing factors and never received ARDs. The patient underwent surgical treatment, and ustekinumab treatment was suspended for six months. No recurrence of MRONJ was detected after 12 months. Although the new definition of MRONJ excludes antiangiogenic molecules, tyrosine kinase inhibitors, and mTOR inhibitors alone, some cases have been reported with ustekinumab. This report highlights the possibility of MRONJ occurring when taking ustekinumab for Crohn's disease, even without being treated with antiresorptive drugs.

An institutional protocol including socket alveoplasty and primary closure following dental extractions for patients with an elevated risk of developing medication-related osteonecrosis of the jaw

Background The purpose of this study was to evaluate the outcomes of alveoplasty and primary closure following dental extractions in patients with an elevated medication-related osteonecrosis of the jaw (MRONJ) risk.Study design A retrospective review of 46 patients with an elevated MRONJ risk was conducted. This included a total of 124 teeth extracted, due to unrestorable caries (n = 46; 37%) and peri-apical pathology (n = 44; 35%).Results Our results showed 0% (n = 0) of patients in our cohort developed MRONJ post-operatively. Most patients were being treated with intravenous zoledronic acid for breast cancer (n = 23; 50%), with an average of 15 doses (range 1-72).Conclusions This study supports the use of alveoplasty and primary closure for patients with an elevated MRONJ risk. The authors highlight the importance of pre-operative cone beam computed tomography imaging, optimisation of immune status, post-operative prophylactic antibiotics, and the delay of bone modifying agents recommencement as influential factors in mitigating risk and favouring successful outcomes.

The dynamin inhibitor, dynasore, prevents zoledronate-induced viability loss in human gingival fibroblasts by partially blocking zoledronate uptake and inhibiting endosomal acidification

OBJECTIVE

For treatment of medication-related osteonecrosis of the jaw, one proposed approach is the use of a topical agent to block entry of these medications in oral soft tissues. We tested the ability of phosphonoformic acid (PFA), an inhibitor of bisphosphonate entry through certain sodium-dependent phosphate contransporters (SLC20A1, 20A2, 34A1-3) as well as Dynasore, a macropinocytosis inhibitor, for their abilities to prevent zoledronate-induced (ZOL) death in human gingival fibroblasts (HGFs).

METHODOLOGY

MTT assay dose-response curves were performed to determine non-cytotoxic levels of both PFA and Dynasore. In the presence of 50 μM ZOL, optimized PFA and Dynasore doses were tested for their ability to restore HGF viability. To determine SLC expression in HGFs, total HGF RNA was subjected to quantitative real-time RT-PCR. Confocal fluorescence microscopy was employed to see if Dynasore inhibited macropinocytotic HGF entry of AF647-ZOL. Endosomal acidification in the presence of Dynasore was measured by live cell imaging utilizing LysoSensor Green DND-189. As a further test of Dynasore's ability to interfere with ZOL-containing endosomal maturation, perinuclear localization of mature endosomes containing AF647-ZOL or TRITC-dextran as a control were assessed via confocal fluorescence microscopy with CellProfiler™ software analysis of the resulting photomicrographs.

RESULTS

0.5 mM PFA did not rescue HGFs from ZOL-induced viability loss at 72 hours while 10 and 30 μM geranylgeraniol did partially rescue. HGFs did not express the SLC transporters as compared to the expression in positive control tissues. 10 μM Dynasore completely prevented ZOL-induced viability loss. In the presence of Dynasore, AF647-ZOL and FITC-dextran co-localized in endosomes. Endosomal acidification was inhibited by Dynasore and perinuclear localization of both TRITC-dextran- and AF647-ZOL-containing endosomes was inhibited by 30 μM Dynasore.

CONCLUSION

Dynasore prevents ZOL-induced viability loss in HGFs by partially interfering with macropinocytosis and by inhibiting the endosomal maturation pathway thought to be needed for ZOL delivery to the cytoplasm.

Influence of the use of bisphosphonates on the development of postextraction sequelae: Scoping review with mapping evidence of in vivo studies

OBJECTIVE

To map the current scientific landscape regarding the association/causality of medication-related osteonecrosis of the jaw (MRONJ) after tooth extraction under bisphosphonate (BF) therapy to identify knowledge gaps and guide future research.

DATA

This review used the PCC strategy (P = Patient; C = Concept; C = Context).

SOURCES

The MEDLINE/PubMed, Scopus, Web of Science/Clarivate Analytics, and gray literature databases were used.

STUDY SELECTION

Searches were conducted by two independent reviewers until April 2024. Studies involving prior BF use and tooth extraction in humans or animals were included. Among the 176 studies, 73 (41.4 %) were in animals, and 103 (58.5 %) were in humans. Brazil led in animal studies (n = 14; 19.1 %), while Italy led in human studies (n = 14; 13.6 %). Zoledronic acid was the most cited BF (79.4 % in animals; 34.9 % in humans), with intravenous administration being most frequent (38.3 % in animals; 35.9 % in humans). The mandible was the main extraction site (n = 36 in animals; n = 41 in humans). In 91.7 % of the animal studies, sequelae compatible with osteonecrosis signs and symptoms were observed, with bone necrosis being most common (n = 39; 53.4 %). In humans, 93.2 % of studies presented 239 sequelae, with bone necrosis (n = 53; 22.1 %) being the most cited. The main location of sequelae was the mandible (n = 36 in animals; n = 41 in humans).

CONCLUSIONS

Animal studies highlighted bone exposure, notably using murine models, with a significant Brazilian contribution. In human studies, bone necrosis was the main sequela of MRONJ, which has been reported by researchers in the Italy.

CLINICAL SIGNIFICANCE

These findings underscore the importance of careful consideration and monitoring of patients who have a history of bisphosphonate use and who are undergoing tooth extraction, highlighting the potential risk of MRONJ.

Efficacy of submental island flap closing advanced mandibular MRONJ lesion in malignancy patients

OBJECTIVE

This study evaluated the effectiveness of a submental island flap in closing advanced mandibular medication-related osteonecrosis of the jaw (MRONJ) wounds in patients with malignant tumors.

SUBJECTS AND METHODS

A total of 85 patients with stage II and III MRONJ of mandible with malignant tumor as their primary disease were retrospectively analyzed. All patients underwent surgical treatment, and the soft tissue wound closure was performed either with a submental island flap (SIF) or mucoperiosteal flap (MF). Univariate and multifactorial models were applied to analyze the factors influencing patients' prognosis.

RESULTS

Univariate analysis (p = 0.004, OR 0.075-0.575, 95% CI) and binary logistic regression (p = 0.017, OR 0.032-0.713, 95% CI) suggested that the surgical prognosis of SIF wound closure was significantly better than that of MF.

CONCLUSION

Closure of wound after resection of mandibular MRONJ lesions in patients with malignant tumors using SIF had a better clinical prognosis compared with MF.

Surgical and conservative treatment outcomes of medication-related osteonecrosis of the jaw located at tori: a retrospective study

PURPOSE

Tori and exostoses are considered risk factors for the development of medication-related osteonecrosis of the jaw (MRONJ). The aims of this study were to present the prevalence of MRONJ located at tori in the Copenhagen ONJ Cohort, evaluate the surgical treatment of MRONJ located at tori and explore trauma to tori as an additional risk factor in patients on antiresorptive medication.

METHODS

Data from a consecutive series of 506 patients with MRONJ (Copenhagen ONJ Cohort) were reviewed for the presence of tori and MRONJ located at tori. Demographic and medical data were analyzed, and healing outcomes and pain after the prophylactic removal of tori, surgical treatment of MRONJ located at tori, and conservative treatment of MRONJ located at tori were evaluated and compared using Fisher's exact test.

RESULTS

MRONJ located at tori was frequent and could be identified in 53% of the patients with tori, which accounts for a prevalence of 5.1% in the entire cohort. Of the 28 surgically treated patients, 27 (96.4%) healed uneventfully with no exposed bone after their first or second revision surgery. Fourteen (41.2%) patients with tori underwent therapeutic removal, eight (23.5%) underwent prophylactic removal, and six (17.6%) underwent both therapeutic and prophylactic removals. Two (33.3%) of the six conservatively treated patients healed spontaneously. Both treatment types resulted in a significant decrease in pain.

CONCLUSION

Prophylactic and therapeutic surgical removal of tori are reliable treatments and should be considered if a patient's general health allows surgery.

TRIAL REGISTRATION

The study was approved by the Regional Scientific Ethical Committee (H-6-2013-010) on November 20, 2013, and was retrospectively registered.

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.

Fufang Zhenshu Tiaozhi capsule enhances bone formation and safeguards against glucocorticoid-induced osteoporosis through innovative Mekk2-mediated β-catenin deubiquitination

INTRODUCTION

Bone homeostasis depends on the regulation of β-catenin in osteoblasts. Glucocorticoids (GCs) are known to diminish β-catenin activity via Wnt pathway signaling, leading to osteoporosis. Conversely, activating β-catenin in osteoblasts through mitogen-activated protein kinase kinase kinase 2 (Mekk2) offers an innovative approach to combat GC-induced osteoporosis (GIOP). Fufang Zhenshu Tiaozhi (FTZ) capsules have shown effectiveness in treating GIOP, but the mechanisms behind this are still unclear.

MATERIALS AND METHODS

In this study, Mekk2 knockout mice (Mekk2-/-) was generated by CRISPR/Cas9. These mice were then subjected to Alcian Blue-Alizarin Red staining and immunofluorescence to assess their bone and cartilage development. To establish models of GIOP, both Mekk2-/- and wild-type (WT) mice were treated with dexamethasone (DXMS) and subsequently given FTZ capsules. We analyzed the resulting phenotypic changes in these mice using Micro-CT scans and histomorphological studies. Primary osteoblasts, isolated from both Mekk2-/- and WT mice, underwent qRT-PCR to measure key osteogenesis markers, including Runx2, Sp7, Bgalp, Col1a1 and Alp. Cells were then exposed to treatments with either FTZ or Wnt3a and the phosphorylation levels of β-catenin and Mekk2, along with the protein expression of Runx2, were evaluated using Western blotting and immunoprecipitation. Additionally, C3H10T1/2 cells transfected with TOPflash-luciferase and Renilla luciferase reporters were treated with FTZ and Wnt3a to measure β-catenin activity.

RESULTS

In our study, administering FTZ in vivo effectively prevented bone loss typically induced by GCs. However, it's important to note that this protective effect was substantially reduced in mice lacking Mekk2. Additionally, FTZ showed a significant ability to enhance osteogenic differentiation in primary osteoblasts, doing so by altering the expression of Mekk2. Intriguingly, the impact of FTZ on Mekk2 appears to function through a pathway separate from the traditional Wnt signaling route. Furthermore, our findings indicate that FTZ also promotes the deubiquitination of β-catenin, contributing further to its positive effects on bone health.

CONCLUSIONS

This study suggests that FTZ plays a significant role in protecting bone mass in cases of GIOP. The mechanism through which FTZ confers this benefit involves the activation of Mekk2/β-catenin signaling pathways, which represents a promising alternative strategy to counteract the deleterious effects of GIOP by augmenting osteoblastogenesis.

Italian position paper (SIPMO-SICMF) on medication-related osteonecrosis of the jaw (MRONJ)

OBJECTIVE

This paper aims to describe the 2023 update position paper on MRONJ developed by the Italian Societies of Oral Pathology and Medicine (SIPMO) and of Maxillofacial Surgery (SICMF).

METHODS

This is the second update following the 2013 and 2020 Italian position papers by the Expert panel, which is a representation of the two scientific societies (SIPMO and SICMF). The paper is based on an extensive analysis of the available literature from January 2003 to February 2020, and the subsequent review of literature conducted between March 2020 and December 2022 to include all new relevant published papers to confirm or modify the previous set of recommendations.

RESULTS

This position paper highlights the main issues of MRONJ on risk estimates, disease definition, diagnostic pathway, individual risk assessment, and the fundamental role of imaging in the diagnosis, classification, and management of MRONJ.

CONCLUSION

The Expert Panel confirmed the MRONJ definition, the diagnostic work-up, the clinical-radiological staging system and the prophylactic drug holiday, as recognized by SIPMO-SICMF; while, it presented novel indications regarding the categories at risk of MRONJ, the prevention strategies, and the treatment strategies associated with the therapeutic drug holiday.

Ozone infiltration as an adjunctive treatment to piezoelectric surgery in the management of medication-related osteonecrosis of the jaws: case series of 29 patients

PURPOSE

Medication-related osteonecrosis of the jaws has been reported to be associated with bisphosphonate and RANKL inhibitor medications. This prospective clinical study aimed to assess the outcomes of pre-operative ozone infiltration therapy in patients with established MRONJ.

METHODS

The treatment protocol for ozone applications were designed as 20 applications ozone infiltration therapy followed by surgical interventions of necrotic tissue debridement using piezoelectric surgery instruments. The evaluation of the results based on the clinical and radiologic specifications considering the necrotic lesion reduction and healing. The study included 31 lesions in 29 patients. The mean follow-up was 23.6 months.

RESULTS

25 lesions out of 31 healed totally without any remissions. The outcomes were not affected by any variables such as gender, age, type of pharmacological treatment, lesion location, and MRONJ staging. The statistically significant results were found among the clinical condition of the patients (p = 0.01) and administration route of medications (p = 0.004). Healing was significantly less in patients that received intra-vascular administrations. Clinical conditions of the patients were divided as osteoporosis, oncologic, and arthritis. Significantly better results were obtained in osteoporosis patients. 38% of the population experienced spontaneous sequestration with signs of improvements and the surgical interventions were canceled. According to the results, total healing of MRONJ lesions was seen in 79% patients (81% lesions).

CONCLUSION

Ozone therapy and debridement with Piezoelectric surgery can be considered as a safe and beneficial adjunctive treatment alternative for osteonecrosis lesions in cases of established MRONJ.

Piezoelectric Surgery, Er:YAG Laser Surgery and Nd:YAG Laser Photobiomodulation: A Combined Approach to Treat Medication-Related Osteonecrosis of the Jaws (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) is a drug complication that can occur in patients taking antiresorptive or antiangiogenic drugs. Although it is a well-documented disease, there is no widely accepted treatment. However, several therapeutic approaches have been proposed. The surgical approach in many advanced cases appears inevitable; however, the results are not yet defined and predictable. This study aimed to propose a combined surgical approach with a piezoelectric device and laser (Er:YAG for bone ablation and Nd:YAG laser for photobiomodulation) in a young patient with breast cancer and bone metastasis under denosumab treatment, affected by spontaneous stage 3 MRONJ with maxillary sinus involvement. The patient under study reported no post-operative discomfort, with painkiller intake limited to the day after surgery. Total mucosal healing was observed without recurrences for more than 4 years after surgery. According to the results of our preliminary study, a combined surgical approach using a piezoelectric device and laser therapy is effective in managing patients affected by MRONJ, leveraging the clinical and biological advantages of these different techniques.

Postoperative pain in oncological patients subjected to nonsurgical root canal treatment: a prospective case-control study

OBJECTIVES

The purpose of this prospective study was to evaluate the incidence and intensity of postoperative pain in oncological patients with infected teeth subjected to nonsurgical root canal treatment or retreatment.

METHODS

Teeth with apical periodontitis from healthy control patients and oncological patients (n = 70 per group) were root canal treated/retreated and evaluated for the development of postoperative pain. Patients from the two groups were matched for tooth type, gender, clinical manifestation of apical periodontitis, and intervention type. A visual analogue scale (VSA) was used to evaluate the incidence of postoperative pain at 24 h, 72 h, 7d, and 15d after chemomechanical procedures. Data were statistically analyzed for the incidence and intensity of postoperative pain in the two groups.

RESULTS

Preoperative pain occurred in 10% of the individuals and in all these cases pain showed a reduction in intensity or was absent after endodontic intervention at 24-h evaluation. The overall incidence of postoperative pain at 24 h was 14% in oncology patients and 30% in controls (p = 0.03). At 72 h, the respective corresponding figures were 4% and 8.5% (p > 0.05). At 7 and 15 days, all patients were asymptomatic, irrespective of the group.

CONCLUSIONS

No significant differences in postoperative pain were found between control and oncological patients. The low incidence of postoperative pain observed in both groups supports the routine use of nonsurgical root canal treatment/retreatment as valid options in oncological patients.

CLINICAL RELEVANCE

Oncological patients had no increased risk of postoperative pain in comparison with control patients.

Cluster-Based Toxicity Estimation of Osteoradionecrosis Via Unsupervised Machine Learning: Moving Beyond Single Dose-Parameter Normal Tissue Complication Probability by Using Whole Dose-Volume Histograms for Cohort Risk Stratification

PURPOSE

Given the limitations of extant models for normal tissue complication probability estimation for osteoradionecrosis (ORN) of the mandible, the purpose of this study was to enrich statistical inference by exploiting structural properties of data and provide a clinically reliable model for ORN risk evaluation through an unsupervised-learning analysis that incorporates the whole radiation dose distribution on the mandible.

METHODS AND MATERIALS

The analysis was conducted on retrospective data of 1259 patients with head and neck cancer treated at The University of Texas MD Anderson Cancer Center between 2005 and 2015. During a minimum 12-month posttherapy follow-up period, 173 patients in this cohort (13.7%) developed ORN (grades I to IV). The (structural) clusters of mandibular dose-volume histograms (DVHs) for these patients were identified using the K-means clustering method. A soft-margin support vector machine was used to determine the cluster borders and partition the dose-volume space. The risk of ORN for each dose-volume region was calculated based on incidence rates and other clinical risk factors.

RESULTS

The K-means clustering method identified 6 clusters among the DVHs. Based on the first 5 clusters, the dose-volume space was partitioned by the soft-margin support vector machine into distinct regions with different risk indices. The sixth cluster entirely overlapped with the others; the region of this cluster was determined by its envelopes. For each region, the ORN incidence rate per preradiation dental extraction status (a statistically significant, nondose related risk factor for ORN) was reported as the corresponding risk index.

CONCLUSIONS

This study presents an unsupervised-learning analysis of a large-scale data set to evaluate the risk of mandibular ORN among patients with head and neck cancer. The results provide a visual risk-assessment tool for ORN (based on the whole DVH and preradiation dental extraction status) as well as a range of constraints for dose optimization under different risk levels.

Precursor Radiographic Findings in Patients With Medication-Related Osteonecrosis of the Jaw

BACKGROUND

Oral surgical treatment, such as tooth extraction, has been identified as a risk factor for the onset of medication-related osteonecrosis of the jaw (MRONJ). However, MRONJ may already be latent, and its manifestation may be triggered by extraction.

PURPOSE

The purpose of this study was to examine the association between pre-extraction imaging and MRONJ.

STUDY DESIGN, SETTING, SAMPLE

We performed a multicenter case-control analysis of patients receiving antiresorptive agents (ARAs) who underwent extraction between 2012 and 2016. We enrolled patients who had undergone tooth extraction in the setting of ARA exposure.

PREDICTOR VARIABLES

The predictor variables comprised preoperative radiographic findings associated with MRONJ stage 0. These findings included alveolar bone loss, thickening or obscuring of the periodontal ligament, and osteosclerosis involving the alveolar bone. They were coded as present or absent before tooth extraction.

MAIN OUTCOME VARIABLE

The primary outcome variable was MRONJ status coded as present or absent.

COVARIATES

Sex, age, underlying diseases necessitating the administration of ARA, the type of ARA used, corticosteroid use, extraction region, and wound closure were analyzed.

ANALYSES

Mann-Whitney U test, χ2 test, Fisher's exact test for univariate analysis, and multiple logistic regression analysis were performed. P values < .05 were significant.

RESULTS

The subjects consisted of 26 patients and 110 controls (male: 8/36, female: 18/74). The mean ages of the MRONJ group and the control group were 77.0 ± 11.9 and 63.0 ± 15.8, respectively (P value = .001). The prevalence of osteosclerosis was significantly higher in the MRONJ group than in the control group (14/72, 53.9%/29.3%, P < .01). Multivariate analysis identified osteosclerosis (odds ratio: 8.4, 95% confidence interval: 2.133.9, P < .01) as a significant independent predictor associated with the development of MRONJ after extraction.

CONCLUSION AND RELEVANCE

These findings suggest that a precursor to MRONJ is highly likely to be present in patients with osteosclerosis at the time of extraction. The majority of patients who developed MRONJ after extraction had imaging findings that suggested infection in the surrounding alveolar bone.

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

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Denosumab-related osteonecrosis of the external auditory canal-benefit of the early surgical management

Background: Antiresorptive drugs are widely used to reduce bone mineral loss in patients with osteoporosis and to prevent skeletal-related events in patients with metastatic cancers and multiple myeloma (MM). Both the bisphosphonates (BP) and denosumab typically used in this indication were shown to be effective and relatively safe. Obviously, this medication could have some adverse effects; one of them is osteonecrosis of the external auditory canal. Only sporadic cases of external auditory canal osteonecrosis have been published yet. Here, we provide a case of denosumab-related osteonecrosis of the external auditory canal successfully treated surgically in the early stage of the disease. Case report: A 68-year-old patient with breast cancer underwent comprehensive oncological treatment, including denosumab administration. She was diagnosed with osteonecroses in the jaw and ear canal. The necrotic bones in both regions were resected with primary wound closure. Both affected sites healed well with no signs of necrosis recurrence. Conclusions: Osteonecrosis of the external auditory canal is a rare but probably underdiagnosed complication of antiresorptive medication. It has a negative impact on patient quality of life if left untreated. Early surgical treatment appears to be effective. The authors highlight several similarities with medication-related osteonecrosis of the jaw. Therefore, an analogous disease staging and treatment rationale is suggested.

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

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

Recognizing bisphosphonate-induced ear osteonecrosis in primary care: a case report

INTRODUCTION

Medication-related ear canal osteonecrosis (MRECO) is a growing concern linked to prolonged anti-resorptive medication use. Despite primary care providers being key prescribers of these medications, there is limited information about MRECO in primary care literature. This article presents a case of bisphosphonate-induced osteonecrosis of the external auditory canal (EAC), emphasizing the vital role of primary care providers in identifying this rare yet significant side effect of anti-resorptive medication.

MAIN SYMPTOMS AND CLINICAL FINDINGS

A 65-year-old female, on long-term alendronic acid for osteoporosis, presented to primary care with a 2-year history of left-sided ear blockage and itchiness. Despite prolonged topical treatment for ear wax, symptoms persisted, leading to an Otolaryngology referral. Microsuction revealed exposed bone in the left EAC.

DIAGNOSES, INTERVENTIONS, AND OUTCOMES

A computed tomography scan confirmed bony erosion of the left EAC, and in the absence of other osteonecrosis risk factors, bisphosphonate-induced osteonecrosis was diagnosed. Management involved bisphosphonate discontinuation, regular aural toilet, and topical treatment, achieving complete ear canal epithelialisation within 6 months.

CONCLUSION

MRECO, a rare complication of anti-resorptive therapy, is anticipated to rise with increasing antiresorptive medication use in the ageing population. Unexplained ear symptoms in those with a history of current or prior anti-resorptive therapy should raise clinical concern, prompting evaluation for exposed bone in the EAC. Raising awareness of MRECO among primary care providers is crucial for early diagnosis and timely management.

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

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

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

Could MRONJ Be Related to Osimertinib Monotherapy in Lung Cancer Patients after Denosumab Suspension?

BACKGROUND

Medication-related osteonecrosis of the jaws is the most frequent complication in patients treated or in therapy with antiresorptive/antiangiogenetic drugs. The list of medications possibly related to MRONJ onset is constantly growing; we aimed to report on a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (Osimertinib) as possibly responsible for bilateral maxillary necrosis onset in the herein-described case.

METHODS

In June 2023, an oncologic patient with two different maxillary bone exposures was referred to our attention. His medical history revealed a two-year Denosumab regimen along with Osimertinib, the latter not suspended before teeth extractions. The clinicians performed a sequestrum removal and bone debridement after three cycles of antibiotic therapy.

RESULTS

Histologic examinations confirmed the clinical diagnosis of MRONJ excluding a metastatic occurrence, while complete mucosal healing was achieved after 15 days.

CONCLUSIONS

The patient suspended Denosumab for more than six months before teeth extraction for MRONJ prevention; hence, failure to discontinue Osimertinib led us to consider it a possible etiological factor. From a literature analysis, only one case has already been published reporting a possible Osimertinib-related occurrence of MRONJ in lung cancer patients. Our case is a further report that could be intended as an alert both for oncologists and dentists to share decisions about the oral management of such patients together, also informing them about this possible risk. Also, this report could trigger in the scientific community the necessity to evaluate further guidelines for similar doubtful cases in which the drug interaction, the mono-suspension, and the possible removable prosthesis-related additional trauma should be considered causes or con-causes.

Treatment and Management of the Clinical Manifestations of Advanced Breast Cancer

OBJECTIVES

People with advanced breast cancer (ABC) experience complex and debilitating physical symptoms of their disease that can have a profound effect on quality of life. This report provides an overview of the clinical manifestations related to different metastatic sites in ABC and potential oncologic emergencies.

DATA SOURCES

Date sources include peer-reviewed papers sourced in electronic databases (CINAHL, MEDLINE, Google Scholar) and national and international best practice guidelines.

CONCLUSION

People living with ABC experience multiple symptoms of disease that can impact on quality of life and physical functioning. The most common sites of metastatic disease are bone, lung, liver and brain. Clinical manifestations of ABC include pain, pathologic fractures, pleural effusions, and ascites. Potential oncologic emergencies related to these metastatic sites include hypercalcemia, malignant spinal cord compression, superior vena cava obstruction, and raised intracranial pressure.

IMPLICATIONS FOR NURSING PRACTICE

It is important for nurses to have informed knowledge and understanding of these clinical manifestations. This will enable them to be vigilant and perform targeted patient evaluation to assess signs and symptoms with a view to identifying potentially life-threatening emergencies and initiating interventions or appropriate referral or follow-up accordingly.

Navigating the complexities and controversies of medication-related osteonecrosis of the jaw (MRONJ): a critical update and consensus statement

OBJECTIVES

To provide a critical update identifying the knowledge gaps and controversies in medication-related osteonecrosis of the jaw (MRONJ) within the Belgian healthcare context and outline opportunities for improvement and research in these areas.

METHODS

A literature review was performed to identify guidelines from international clinical societies in oncology or oral and maxillofacial surgery on diagnosing, preventing, and treating MRONJ. The recommendations were critically assessed in light of recent developments in the field and confronted with the clinical experience of experts.

RESULTS

Despite progress in the diagnostic criteria of MRONJ, the continued need for an 8-week timeout period should be reconsidered. Furthermore, 3D imaging techniques should be introduced to improve diagnosis and staging. The staging system remains ambiguous regarding Stage 0 MRONJ, and ongoing confusion exists regarding the term non-exposed MRONJ. The prevention of MRONJ should be tailored, considering the individual patient's risk of MRONJ, frailty, and life expectancy. More research seems needed into the efficacy and safety of drug holidays, considering the risks of rebound remodeling on fractures. With renewed interest in surgical and adjunct management techniques, adequately designed clinical studies are needed to help translate trial outcomes into universally applicable treatment guidelines taking into account individual patient characteristics.

CONCLUSIONS

Important knowledge gaps remain and hamper the development of clinical guidelines. Several controversies were identified where consensus is lacking, and further harmonization between stakeholders is necessary. Finally, the need for randomized controlled comparative clinical trials in MRONJ resonates harder than ever to identify the best treatment for individual patients.

Osteonecrosis of the jaw under palbociclib: A case series description

INTRODUCTION

Cases of osteonecrosis of the jaw have been reported by dental surgeons to the pharmacovigilance center in Rennes, France, occurring among patients treated with palbociclib, a cyclin-dependent kinase 4/6 inhibitor. Although this event was not expected with the drug, a safety signal was raised. Describing a local case series, the aim of our study was to identify specific patterns that might suggest a triggering role for these drugs, and to discuss pathophysiological hypotheses.

MATERIALS AND METHODS

A retrospective case series of patients exposed to cyclin-dependent kinase 4/6 inhibitors between 2016 and 2020 with a diagnosis of osteonecrosis of the jaw at the Rennes Dental Care Center was analyzed. The descriptive analysis was conducted on patient demographics, breast cancer characteristics, osteonecrosis of the jaw, biological data, and exposure to cyclin-dependent kinase 4/6 inhibitors.

RESULTS

We identified eight cases, most of them at stages 0-1 (62.5%). Four patients were still exposed to palbociclib at the time of diagnosis and four had discontinued the treatment before the diagnosis. Chronological imputability could not be excluded given the drug's half-life and the variable intervals of dental monitoring from one patient to another. All patients had at least one dental osteonecrosis risk factor (including dental extraction, dentures, and denosumab exposure at the time of diagnosis). Neutropenia and mucositis were not systematically reported at the time of diagnosis. The anatomopathological characteristics were nonspecific.

CONCLUSION

We did not identify a specific pattern that could suggest a triggering role of palbociclib in the development of ONJ.

Dose-dependent effects of zoledronic acid on the osteogenic differentiation of human bone marrow stem cells (hBMSCs)

Recent studies have shown that bisphosphonates can also impact osteoblasts besides osteoclasts. This study aimed to evaluate the effects of different concentrations of Zoledronic acid (ZA) during the osteogenic differentiation of human Bone Marrow Stem Cells (hBMSCs) in vitro. Thus, osteogenic differentiation of hBMSCs was conducted with different concentrations of Zoledronic Acid (ZA) (0, 0.1, 1.0, and 5.0 μM) for the first 3 days. Cell metabolism was quantified at 1-, 3-, 7-, and 14 days. At 7- and 14-days, the following analyses were performed: 1) mineralization nodule assay, 2) LIVE/DEAD™, 3) cell adhesion and spreading, 4) alkaline phosphatase (ALP) activity, and 5) qPCR analysis for RUNX-2), ALPL, and COL1 A1. Data were analyzed by ANOVA 2-way, followed by Tukey's post hoc test (p < 0.05). Cell metabolism (3-, 7-, and 14-days) (p < 0.001), mineralization (7-, 14-days) (p < 0.001), and ALP activity (14-days) (p < 0.001) were reduced in ZA 5.0 µM when compared to control (no ZA). Also, ZA 5.0 µM downregulated the expression of RUNX2 at 7- and 14-days (p < 0.001). It is possible to conclude that ZA (5.0 µM) can impair hBMSC differentiation into osteoblasts and interferes with its mineralization phase.

Bisphosphonates and osteonecrosis of the jaws: Clinical and forensic aspects

OBJECTIVE

This manuscript aims to provide a comprehensive review of the current knowledge in the pathophysiology, diagnosis, prevention, and other relevant clinical and forensic aspects of a potentially severe complication known as medication-related osteonecrosis of the jaw (MRONJ) while synthesizing state-of-the-art information on bisphosphonates and introducing a possible differential diagnosis.

DESIGN

An extensive search was conducted in PubMed (U.S. National Library of Medicine) without a time or language constraint, focusing on the epidemiology, pathophysiology, risk factors, site specificity, signs and symptoms, differential diagnosis, prevention, and forensic aspects of MRONJ. All types of original articles, reviews, case reports, short communications, opinion articles, guidelines, and letters to editors were considered to produce a complete review on this subject.

RESULTS

MRONJ prevention relies on a multidisciplinary approach and is critical since truly effective treatments are lacking. This therapeutic challenge is partly due to uncertainty regarding this condition's pathophysiology. Differential diagnosis of osteonecrosis of the jaws associated with krokodil abuse, one of the most dangerous and homemade psychoactive illicit substances, should be considered.

CONCLUSIONS

Further research into the etiology and site specificity of MRONJ is encouraged, aiming to develop novel treatment prospects. Indeed, comprehending this would allow for increased efficacy and therapeutic options while emphasizing the importance of prevention. In addition, we advocate for greater consensus among the various societies regarding MRONJ's treatment and management.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The role of E3 ubiquitin ligases in bone homeostasis and related diseases

The ubiquitin-proteasome system (UPS) dedicates to degrade intracellular proteins to modulate demic homeostasis and functions of organisms. These enzymatic cascades mark and modifies target proteins diversly through covalently binding ubiquitin molecules. In the UPS, E3 ubiquitin ligases are the crucial constituents by the advantage of recognizing and presenting proteins to proteasomes for proteolysis. As the major regulators of protein homeostasis, E3 ligases are indispensable to proper cell manners in diverse systems, and they are well described in physiological bone growth and bone metabolism. Pathologically, classic bone-related diseases such as metabolic bone diseases, arthritis, bone neoplasms and bone metastasis of the tumor, etc., were also depicted in a UPS-dependent manner. Therefore, skeletal system is versatilely regulated by UPS and it is worthy to summarize the underlying mechanism. Furthermore, based on the current status of treatment, normal or pathological osteogenesis and tumorigenesis elaborated in this review highlight the clinical significance of UPS research. As a strategy possibly remedies the limitations of UPS treatment, emerging PROTAC was described comprehensively to illustrate its potential in clinical application. Altogether, the purpose of this review aims to provide more evidence for exploiting novel therapeutic strategies based on UPS for bone associated diseases.

Assessment Results of Dental Students' Knowledge about Bisphosphonates and Bisphosphonate-Related Osteonecrosis of the Jaw

Objectives

The aim of this cross-sectional study is to evaluate Lithuanian fourth- and fifth-year dental students' knowledge about bisphosphonates and bisphosphonate-related osteonecrosis of the jaw.

Material and Methods

The anonymous survey using a questionnaire was conducted from February to March 2022. The survey was sent to 173 students at Lithuanian University of Health Sciences (LSMU) and 107 of them were completed. It consisted of student data, questions about the main properties of bisphosphonates, bisphosphonate-related osteonecrosis of the jaw (BRONJ), and the necessity of additional studies for students. Chi-square test and Cramér's V coefficient were used for the analysis of variables.

Results

Most of the fifth-year students knew the main properties of bisphosphonates and what diseases they are used to treat. Twenty fifth-year students (33.9%) knew the accurate definition of BRONJ, while only 11 fourth-year students (22.9%) chose the same correct answer. Statistically significant (P < 0.05) data were found about the knowledge of main properties of bisphosphonates. The vast majority of fourth- and fifth-year students (39 [81.3%] and 45 [76.3%]), agreed that the University should provide more information about bisphosphonates.

Conclusions

The study revealed that fifth-year students demonstrated better knowledge about bisphosphonates compared to fourth-year students and this was due to a curriculum supplemented with information about this pathology. The overall findings of this research suggest that Universities need to expand their student curricula by providing more knowledge about bisphosphonates and its relation to bisphosphonate-related osteonecrosis of the jaw.

Correlations between Immune Response and Etiopathogenic Factors of Medication-Related Osteonecrosis of the Jaw in Cancer Patients Treated with Zoledronic Acid

Impairment of the immune response in MRONJ (medication-related osteonecrosis of the jaws) is one of the still unclear etiopathogenic mechanisms of this condition encountered in cancer patients treated with bisphosphonates, with negative effects on the patient's quality of life. The aim of the present study was to correlate the immune response with etiopathogenic factors via immunohistochemical evaluation of the maxillary tissues in zoledronic acid osteonecrosis. The retrospective study included a group of 51 patients with various types of cancers, diagnosed with stage 2 or 3 MRONJ at zoledronic acid and treated surgically. Immunohistochemical expressions of αSMA, CD3, CD4, CD8, CD20, CD79α, CD68, CD204, and tryptase were evaluated. Immunohistochemical markers expressions were statistically analyzed according to the duration of the treatment, the trigger factor, the location of the MRONJ, and the healing status. Analysis of the immune response included T lymphocytes, B lymphocytes, plasma cells, macrophages, and mast cells. The duration of treatment significantly influenced the immunohistochemical expression of most markers (p < 0.05). For an increasing trend in treatment duration, a decreasing trend in marker score was observed, suggesting an inverse correlation. The expression of the markers was different depending on the trigger factor, on MRONJ localization (maxilla/mandible), and the healing status, being more intense in patients cured per primam compared to those who had relapses. The patient's immune response was negatively influenced by the duration of the treatment, the trigger factor, the location of the lesion in the mandible, and the recurrence of MRONJ.

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

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

Aim

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

Materials and methods

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

Results

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

Conclusion

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

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

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

Prosthodontic rehabilitation of a patient with nintedanib-induced osteonecrosis of the jaw: A clinical report

Medication-related osteonecrosis of the jaw results in extensive excision and proves challenging to rehabilitate prosthetically. This article describes the prosthodontic rehabilitation of medication-related osteonecrosis of the jaw induced by nintedanib. A custom-made subperiosteal implant was designed to adapt to the bone, remaining after the excision of the jaw necrosis. The implant followed the anatomic contour of the residual bone and was milled in titanium alloy, allowing the rehabilitation of a patient with a fixed dental prosthesis.

Outcomes of a Pharmacological Protocol with Pentoxifylline and Tocopherol for the Management of Medication-Related Osteonecrosis of the Jaws (MRONJ): A Randomized Study on 202 Osteoporosis Patients

Medication-related osteonecrosis of the jaws (MRONJ) is a challenging situation in clinics. Previous studies have shown that pentoxifylline combined with tocopherol proved to be beneficial in patients with osteoradionecrosis, due to their antioxidant and antifibrotic properties. The aim of this randomized study was to evaluate the effect of pentoxifylline and tocopherol in patients that had developed MRONJ after tooth extractions. The study population consisted of 202 Stage I MRONJ female patients with an average age of 66.4 ± 8.3 years, who were divided into two groups. The test group (n = 108) received a pharmacological protocol with pentoxifylline and tocopherol (2 months pre-operatively and 6 months post-operatively). The control group (n = 94) had sequestrectomy operations without any pharmacological preparation. The main outcomes were clinical healing of the mucosa after 1 month, and clinical and radiographic healing of the bone lesion at 6 months. In the test group all patients had mucosal healing and there was only one relapse within 6 months. In the control group, in 17% of the patients the mucosa did not heal, 71% of the patients relapsed within two months, and 7% developed infectious complications (such as abscess or phlegmon). After 6 months, the control group patients with persisting issues were prescribed pentoxifylline and tocopherol, as in the test group. At a subsequent follow-up, all those patients healed completely. Patients were monitored for a period of 7.8 ± 0.3 years, during which no relapse or additional problems were reported. As a conclusion, pentoxifylline and tocopherol protocol seems to be beneficial in the management of MRONJ patients.

Evaluation of Preventive Role of Systemically Applied Erythropoietin after Tooth Extraction in a Bisphosphonate-Induced MRONJ Model

Background and Objectives: In this experimental study, the prophylactic effect of systemically administered erythropoietin (EPO) in medication-related osteonecrosis of the jaw (MRONJ) was evaluated. Materials and Methods: The osteonecrosis model was established using 36 Sprague Dawley rats. EPO was systemically applied before and/or after tooth extraction. Groups were formed based on the application time. All samples were evaluated histologically, histomorphometrically, and immunohistochemically. A statistically significant difference in new bone formation was observed between the groups (p < 0.001). Results: When new bone-formation rates were compared, no significant differences were observed between the control group and the EPO, ZA+PostEPO, and ZA+Pre-PostEPO groups (p = 1, 0.402, and 1, respectively); however, this rate was significantly lower in the ZA+PreEPO group (p = 0.021). No significant differences in new bone formation were observed between the ZA+PostEPO and ZA+PreEPO groups (p = 1); however, this rate was significantly higher in the ZA+Pre-PostEPO group (p = 0.009). The ZA+Pre-PostEPO group demonstrated significantly higher intensity level in VEGF protein expression than the other groups (p < 0.001). Conclusions: Administering EPO two weeks pre-extraction and continuing EPO treatment for three weeks post-extraction in ZA-treated rats optimized the inflammatory reaction, increased angiogenesis by inducing VEGF, and positively affected bone healing. Further studies are needed to determine the exact durations and doses.