The impact of surgical intervention and antibiotics on MRONJ stage II and III – Retrospective study

Epidemiology, etiopathogenesis, and management of MRONJ: A European multicenter study

INTRODUCTION

The purpose of this European multicenter study was to describe the general characteristics and risk factors of MRONJ lesions as well as their clinical diagnosis and management at different European Oral and Maxillofacial Surgery centers, in order to minimize selections biases and provide information about the epidemiology, etiopathogenesis, and the current trends in the treatment of MRONJ across Europe.

MATERIALS AND METHODS

The following data were registered for each patient: gender; age at MRONJ diagnosis; past medical history; indication for antiresorptive or antiangiogenic therapy; type of antiresorptive medication; local risk factor for MRONJ; MRONJ Stage; anatomic location and symptoms; treatment; surgical complications; recurrence.

RESULTS

A total of 537 patients (375 females, 162 males) with MRONJ were included. Statistically significant associations were found between patients with metastatic bone disease and recurrences (P < 0.0005) and between advanced MRONJ stages (stages 2 and 3) and recurrences (P < 0.005). Statistically significant associations were also found between male gender and recurrences (P < 0.05), and between MRONJ maxillary sites and recurrences (P < 0.0000005).

CONCLUSIONS

A longer mean duration of antiresorptive medications before MRONJ onset was observed in patients affected by osteoporosis, whereas a shorter mean duration was observed in all metastatic bone cancer patients, and in particular in those affected by prostate cancer with bone metastases or multiple myeloma. Surgery plays an important role for the management of MRONJ lesions.

Risk factors associated with prognosis of patients with medication-related osteonecrosis of the jaw

OBJECTIVES

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse effect of antiresorptive and/or antiangiogenic agents. As the treatment application for MRONJ is controversial, we aimed to identify the risk factors for poor prognosis and to help determine appropriate management.

METHODS

This study included 119 patients. Relevant clinical data were obtained for all the patients. In computed tomography images, osteosclerosis, osteolysis, cortical perforation (buccal or lingual), periosteal reaction, and sequestration were evaluated.

RESULTS

Multivariate analyses showed statistically significant associations between poor prognosis in patients with MRONJ and conservative treatment alone (hazard ratio [HR] 1.89), osteolysis (HR 4.67), and the absence of sequestration (HR 5.33).

CONCLUSIONS

Conservative treatment alone without clear objectives needs to be avoided, and osteolytic change could be the criteria for surgical intervention. As the boundary between the lesion and vital bone is indistinct, we recommend extensive surgery in cases with unpredictable sequestration.

Drug holiday of high-dose denosumab and recovery from osteoclast inhibition using immunohistochemical investigation of 7 patients with medication-related osteonecrosis of the jaw undergoing segmental mandibulectomy

Background/purpose

Denosumab is used to treat bone metastases from malignant tumors. Unlike bisphosphonates, denosumab is not deposited in the bone; thus, withdrawal for a relatively short period would help recovery from osteoclast suppression. This study investigated the relationship between drug holidays and recovery from osteoclast suppression.

Materials and methods

Seven patients who received high-dose denosumab and underwent segmental mandibulectomy for medication-related osteonecrosis of the jaw were enrolled in this study. Osteoclast suppression (+) was defined as the absence of cathepsin K-positive cells or cathepsin K-positive mononuclear or small multinucleated cells observed on the bone surface of both mesial and distal specimens. When normal osteoclasts were found, osteoclast suppression was defined as (-); when both suppressed cathepsin K-positive cells and normal morphological osteoclasts were found, it was defined as (±).

Results

Osteoclast suppression was: (+) in four patients, three without a drug holiday and one with a 9-month drug holiday; (±) in one patient with an 8-month drug holiday, and (-) in two patients with drug holidays for 13 and 20 months.

Conclusion

These findings suggest that a long-term drug holiday, such as 12 months, is required for recovery from osteoclast suppression in patients with cancer receiving high-dose denosumab.

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

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

Relationship between drug holiday of the antiresorptive agents and surgical outcome of medication-related osteonecrosis of the jaw in osteoporosis patients

A drug holiday of 3 months does not promote separation of sequestra and is not correlated with treatment outcomes after surgical therapy in osteoporosis patients who receive antiresorptive agents and who have medication-related osteonecrosis of the jaw. Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse effect of antiresorptive agents alone or in combination with immune modulators or antiangiogenic medications, in the absence of radiation exposure to the head and neck region. The effectiveness of surgical treatment for MRONJ has been reported, but the timing of the operation remains controversial. The purpose of this study was to clarify whether preoperative drug holidays of antiresorptive agents promote sequestrum separation and improve treatment outcomes in patients who receive low doses of antiresorptive agents. This retrospective study included 173 patients who received low-dose antiresorptive agents and underwent surgical therapy. The effects of a drug holiday on the separation of sequestra and treatment outcomes were analyzed using logistic and Cox regression analyses. Multivariate analysis revealed that administration of an antiresorptive agent for more than 4 years, a high number of lymphocytes, and an extensive osteolytic area were significantly correlated with separation of sequestra, but drug holiday did not promote sequestrum separation. Furthermore, a drug holiday of 90, 120 or 180 days did not show any improvement in treatment outcomes. The drug holiday of the antiresorptive agents for the treatment of MRONJ is unnecessary, and surgical therapy should be performed early.

Retrospective Analysis of Treatment Outcomes of Maxillary Sinusitis Associated with Medication-Related Osteonecrosis of the Jaw

Although maxillary sinusitis often occurs in patients with medication-related osteonecrosis of the jaw (MRONJ) of the upper jaw, there have been few reports on the treatment and outcomes for maxillary sinusitis associated with maxillary MRONJ. This study aimed to retrospectively investigate the treatment outcomes of maxillary sinusitis in patients with MRONJ of the upper jaw. There were 34 patients diagnosed with maxillary MRONJ and sinusitis by preoperative computed tomography who underwent surgery in our institution between January 2011 and December 2019. Age, sex, primary disease, stage of MRONJ, class and administration period of an antiresorptive agent, corticosteroid administration, preoperative leukocyte count and serum albumin level, periosteal reaction, sinusitis grade, maxillary sinus surgical procedure, and treatment outcomes of MRONJ and sinusitis were examined. There were 7 male and 27 female patients (average age, 74.7 years). Complete healing of MRONJ was obtained in 29 of 34 patients (85.3%). Maxillary sinusitis resolved or improved in 21 patients (61.8%) but did not change or worsen in 13 patients (38.2%). We found that complete resection of necrotic bone with intraoperative irrigation of the maxillary sinus may provide good treatment outcomes for maxillary sinusitis associated with MRONJ, although our findings were not statistically significant owing to the small number of patients.

[Bisphosphonate-related osteonecrosis of the jaws]

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

Antibiotics in Dentoalveolar Surgery, a Closer Look at Infection, Alveolar Osteitis and Adverse Drug Reaction

PURPOSE

To execute an evidence-based review answering the following questions: "What antibiotic type and mode of delivery are most effective at reducing inflammatory complications in third molar and dental implant surgery? What are the types and rates of antibiotic-related adverse reactions in the context of third molar surgery, infective endocarditis, medication-related osteonecrosis of the jaw (MRONJ) and osteoradionecrosis (ORN)?"

MATERIAL AND METHODS

We performed a comprehensive literature review of peer-reviewed studies using MEDLINE/PubMed, Cochrane, Scopus/Elsevier, Google Scholar, and Wiley online library databases.

RESULTS

Twenty-five studies were reviewed for third molar surgery. Although there is some evidence that systemic antibiotics reduce inflammatory complications (infection and alveolar osteitis), routine use is not recommended for third molar surgery. For at-risk cases, a single preoperative dose of amoxicillin is preferred. Clindamycin, amoxicillin-clavulanic acid and erythromycin have a high adverse risk profile. Eight studies were reviewed for dental implant surgery. Antibiotics with dental implant placement showed little reduction in post surgery infection and minimal improvement in long-term success. A comprehensive search found limited data on antibiotic-related adverse effects in the context of infective endocarditis, MRONJ and ORN.

CONCLUSIONS

A set of clinical recommendations are presented to better guide evidence-based and standardized antibiotic usage on the basis of the literature discussed in this review. This review highlights the need for further research focusing on antibiotic type and timing of delivery with adverse drug reaction as a primary outcome measure when assessing treatment outcomes and complications in dentoalveolar surgery. This will better elucidate the risks vs benefits of antibiotic in dentoalveolar surgery.

CD34 and CD105 Microvessels in Resected Bone Specimen May Implicate Wound Healing in MRONJ

Clinical treatment outcome of MRONJ (medication-related osteonecrosis of the jaw) surgery despite radical osseous removal and primary closure healing still shows differences in terms of outcome and disease recurrence. The study aims to assess the rate of angiogenesis of MRONJ lesions in order to understand the impact of angiogenesis and neoangiogenesis status on MRONJ surgical treatment outcome. This is the first study correlating microvessel density with prognosis in MRONJ surgically-treated patients. The immunohistochemical expression of CD34 and CD105 in MRONJ specimens obtained from surgically-treated patients was evaluated. The most vascularized areas detected by CD34 and CD105 were selected and the microvessel density value of the samples was registered. Samples were retrospectively divided according to the clinical outcome of MRONJ surgical treatment, dividing patients into two groups, “healed” and “not healed”. Statistical analysis was performed to assess if neovessels could influence treatment outcome in patients undergoing radical surgery. In the examined cohort, this value was highly predictive of better treatment outcome after radical surgery of MRONJ. Understanding of angiogenesis-dependent factors deserves further attention as a future target for MRONJ prevention and therapies.

Analysis of Factors Associated with the Postoperative Healing of Medication-Related Osteonecrosis of the Jaw in Patients with Osteoporosis

BACKGROUND

Surgical treatment is considered the best approach by many researchers for medication-related osteonecrosis of the jaws (MRONJ). While postoperative outcomes are mainly favorable, wound healing still fails in some cases. This retrospective study aimed to evaluate the factors affecting the postoperative healing of MRONJ.

METHODS

This study involved 400 osteoporosis patients who received surgical treatment from January 2009 to January 2018 in Kyungpook National University Hospital. The patient, drug, and clinical factors were collected as investigation variables. The obtained data were statistically analyzed to identify relationships between the factors and healing aspect.

RESULTS

Univariate logistic regression analysis showed that the route of drug administration, bone exposure, types of surgical management, and wound management had a significant influence (p < 0.05) on the healing outcome. Sequestrectomy with primary closure had a more positive effect on favorable healing. In the multivariate logistic regression test, the effect of wound management alone was not statistically significant (p > 0.05).

CONCLUSION

In patients with osteoporosis, the factors such as intravenously administered drugs, fistulas that were probed to the bone, and surgical management with curettage were associated with a lower rate of postoperative complete healing of MRONJ, whereas primary closure of wounds led, possibly, to good healing outcomes. The strengths of the study include its relatively large sample size and that its results can hopefully aid in the clinical decisions for practitioners and future research studies for researchers.

Antibiotic prescribing at a periodontal residency practice in Connecticut

BACKGROUND

Antibiotics are important in the treatment of odontogenic infections and the prevention of infection following dental procedures in high-risk situations. Little is known about antibiotic prescribing in periodontal practice. This study describes prescribing practices by periodontal faculty and residents in an academic setting in order to identify opportunities to optimize prescribing behaviors.

METHODS

This cross-sectional study analyzed all antibiotic prescriptions from residents or faculty in an academic periodontal clinic from 2014-2017. Information was manually extracted from the electronic health record. Antibiotic prescriptions were stratified into three indication categories: pre-procedural prophylaxis, post-procedural prophylaxis, and treatment.

RESULTS

Out of 275 prescriptions analyzed, 266 met inclusion criteria. The most frequent antibiotic indication was post-procedural prophylaxis (n = 130, 48.87%). Amoxicillin was the most frequently prescribed antibiotic across all groups (n = 236, 88.72%), followed by clindamycin (n = 22, 8.27%). Most patients presented in a non-emergent setting (n = 200, 75.19%), without pain (n = 210, 78.95%), and had restorative/endodontic-related clinical findings (n = 55, 20.68%). Among the 35 patients receiving antibiotics for infection treatment, 8 (22.86%) underwent a surgical intervention on the date of antibiotic prescription. Of the 130 patients receiving post-procedural prophylaxis, 121 (93.08%) received surgical interventions on the day of antibiotic prescription.

CONCLUSIONS

Antibiotics are prescribed in various situations in periodontal practice, most frequently as post-procedural prophylaxis, an indication for which data is limited. There is an urgent need to study the role of post-procedural prophylactic antibiotics and understand antibiotic prescribing in the management of periodontal disease in order to optimize prescribing practices.

Effectiveness of surgery and hyperbaric oxygen for antiresorptive agent-related osteonecrosis of the jaw: A subgroup analysis by disease stage

Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is an adverse event induced by antiresorptive agents (ARAs). The purpose of this study was to evaluate variables, mainly surgery and hyperbaric oxygen (HBO) therapy, associated with treatment outcomes in patients with a diagnosis of ARONJ at a single center. We enrolled consecutive patients who presented to our hospital for the management of stage 2 or 3 ARONJ between January 2003 and December 2019. The relationship between potentially predictive factors and outcome variables was examined using statistical analyses, along with a subgroup analysis based on disease stage. Of 252 patients included in this study, 206 had stage 2 ARONJ and 46 had stage 3 ARONJ. There were 119 patients with osteoporosis and 133 with malignant disease. In total, 139 patients were healed, and the healing rate of patients with stage 3 ARONJ was lower than that of patients with stage 2 ARONJ. With regard to the combination of surgery and HBO therapy, most patients underwent HBO before and after surgery. In the univariable analysis, surgery showed a therapeutic effect in both stage 2 and 3 ARONJ, whereas HBO showed a therapeutic effect in stage 2 ARONJ. In the multivariable analysis for stage 2 ARONJ, extensive surgery showed a stronger association with healing than conservative surgery, whereas ≥46 sessions of HBO therapy was less associated with healing than was non-HBO therapy. Our findings suggest that extensive surgery is highly effective against ARONJ regardless of disease stage if there is a sequestrum separation and systemic tolerance, whereas HBO therapy before and after surgical approach can be effective. Further studies are needed to identify treatment strategies for patients with treatment-refractory ARONJ who may be forced to undergo long-term HBO therapy with the expectation of sequestrum separation.

Evaluation of segmental mandibular resection without microvascular reconstruction in patients affected by medication-related osteonecrosis of the jaw: a systematic review

Medication-related osteonecrosis of the jaw (MRONJ) is a severe condition that affects the jaw in patients exposed to specific drugs. More often it has been described in association with bisphosphonates (BP), but nowadays it has been observed with the use of other medications, such as denosumab (a RANK ligand inhibitor and monoclonal antibody agent) and antiangiogenic drugs. Managing the condition has unfortunately proven difficult and still remains a major challenge for clinicians and surgeons. The aim of this systematic review was to identify and analyse the evidence on mandibular segmental resection in patients with advanced MRONJ. A multi-database (PubMed, MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials) systematic search was performed. Any type of study on human patients treated with antiresorptive and antiangiogenic drugs was considered. The primary aim was to understand the success of mandibular segmental resection in the short, medium, and long term, and to understand its effects before, during, and after the operation. The search yielded 11 studies that were eligible for analysis with a total of 67 patients. Of the 11 studies, seven reported no complications, and overall, postoperative complications were seen in 16 cases. Recurrence of osteonecrosis was reported in one study. The most common postoperative complication was removal of hardware (n = 11). The mean (SD) follow-up time for eight studies was 35.57 (17.73) months. According to the limited data available in the literature, mandibular segmental resection is a viable treatment that has been used successfully in patients with various stages of MRONJ. The data show a relatively high percentage of recurrence. Additional data based on a larger cohort of patients or case-control studies are necessary to justify routine use of this type of intervention in patients affected by the condition.

The Case of Medication-Related Osteonecrosis of the Jaw Addressed from a Pathogenic Point of View. Innovative Therapeutic Strategies: Focus on the Most Recent Discoveries on Oral Mesenchymal Stem Cell-Derived Exosomes

Bisphosphonates-related osteonecrosis of the jaw (BRONJ) was firstly reported by Marx in 2003. Since 2014, the term medication-related osteonecrosis of the jaw (MRONJ) is recommended by the American Association of Oral and Maxillofacial Surgeons (AAOMS). Development of MRONJ has been associated to the assumption of bisphosphonates but many MRONJ-promoting factors have been identified. A strong involvement of immunity components has been suggested. Therapeutic intervention includes surgical and non-surgical treatments, as well as regenerative medicine procedures for the replacement of the lost tissues. The literature confirms that the combination of mesenchymal stem cells (MSCs), biomaterials and local biomolecules can support the regeneration/repair of different structures. In this review, we report the major open topics in the pathogenesis of MRONJ. Then, we introduce the oral tissues recognized as sources of MSCs, summing up in functional terms what is known about the exosomes release in physiological and pathological conditions.

Combined Administration of Bisphosphonates, Chemotherapeutic Agents, and/or Targeted Drugs Increases the Risk for Stage 3 Medication-Related Osteonecrosis of the Jaw: A 4-Year Retrospective Study

Objectives

Patients with stage 3 medication-related osteonecrosis of the jaw (MRONJ) suffer from severe complications. Chemotherapeutic agents and targeted drugs are considered to be associated with the development of MRONJ. However, little is known regarding the association of those agents with stage 3 MRONJ. The purpose of this study is to analyze the comprehensive medication history of patients with advanced-stage MRONJ (stage 2 and stage 3) and evaluate the possible risk factors for stage 3 MRONJ. Patients and Methods. Sixty patients with advanced-stage MRONJ were involved in this retrospective study. Patients with developmental maxillofacial anomalies, previous radiation in the head and neck areas, and jaw bone tumors were excluded from the study. All patients were divided into two groups by their MRONJ stage (stage 2 or stage 3). Demographic and clinical characteristics, comprehensive medication data (bisphosphonates, chemotherapeutic agents, targeted drugs, and immunosuppressive agents), and results of serological biomarkers were recorded and compared between two groups. Univariate and multivariate logistic regressions were performed by SPSS 25.0 for evaluating risk factors of stage 3 MRONJ.

Results

Our results indicate that chemotherapy (adjusted OR = 3.43; 95% CI: 1.03 to 11.38), targeted drugs (adjusted OR = 3.69; 95% CI: 1.06 to 12.80), and maxillary lesions (adjusted OR = 4.26; 95% CI: 1.19 to 15.23) increase the risk of stage 3 MRONJ.

Conclusion

The outcome of this study justifies that chemotherapeutic agents and targeted drugs are probably risk factors for stage 3 MRONJ. In addition, the osteonecrosis in maxilla is more easily to develop into stage 3 MRONJ. Intense clinical observation is recommended in MRONJ patients with maxillary osteonecrosis and in those who concurrently administered bisphosphonates, chemotherapeutic agents, and/or targeted drugs. This trial is registered with ChiCTR2000032428.

Antimicrobial peptide gene expression in medication-related osteonecrosis of the jaw

Bisphosphonates and denosumab are commonly used antiresorptive therapies in patients with bone metastasis and osteoporosis. Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect of these drugs, and infection has been recognized as a contributing factor. Current therapeutic options for MRONJ show limited effectiveness, therefore necessitating novel treatment strategies. Bisphosphonates have recently been reported to induce the expression of antimicrobial peptides (AMPs), an inherent component of the immune system. Therefore, the aim of the present study was to investigate and compare the influence of the anti-RANKL antibody denosumab and bisphosphonates on the gene expression of selected AMPs: human α-defensin-1, human α-defensin-3, human β-defensin-1, and human β-defensin-3. Bone specimens were collected from patients with MRONJ who had been treated with bisphosphonates (n = 6) or denosumab (n = 6), and from healthy subjects (n = 6) with no history of treatment with bone metabolism-influencing drugs. Reverse transcription-quantitative polymerase chain reaction was used to quantify the expression levels of selected AMPs. Samples from patients treated with denosumab showed significantly higher mRNA expression of human α-defensin-3 and human β-defensin-3 than those from healthy subjects. This finding is similar to previously described upregulated expression of human defensins in patients with MRONJ after bisphosphonates treatment. This suggests that the elevated expression of defensins may be at least a part of the mechanism underlying the pathogenesis of osteonecrosis induced by antiresorptive therapies, which can serve as a new target for potential treatment of MRONJ.

Oral Surgical Management of Bone and Soft Tissues in MRONJ Treatment: A Decisional Tree

Background: The aim of the present work was to analyze a 10-year retrospective series of surgically treated medication-related osteonecrosis of the jaws (MRONJ) cases, reporting the clinical outcome and success rate for each adopted procedure in order to draw a treatment algorithm that is able to standardize clinical decision making and maximize the success of oral surgical treatment of MRONJ. Methods: Different surgical approaches were categorized taking into consideration two variables (a) hard tissue management (defined as debridement, saucerization or marginal resective surgery of maxillary necrotic bone) and (b) soft tissue management (defined as type of flap design and related modality of wound-healing). Results: For the retrospective cohort study, 103 MRONJ patients were enrolled and a total of 128 surgical procedures were performed. The role of radical-intended surgery using local flaps in MRONJ treatment was investigated, as well as palliative treatments. All stage I–II patients completely healed when a combination of radical necrotic bone surgery associated with a first intention healing of soft tissues was obtained. In stage III, when a patient was not eligible for maxillo-facial surgery, the use of palliative surgical strategies was effective in symptom relief in order to maintain a better quality of life for the duration of the patient’s life. Conclusions: Oral surgery with radical intent associated with a flap design able to ensure first intention healing might represent a valid option for the majority of MRONJ patients. The designed decision tree allows clinicians to assess individual surgical approaches for MRONJ treatment in accordance with patient-centered outcomes and surgical skills.

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.

Volumetric analysis of MRONJ lesions by semiautomatic segmentation of CBCT images

PURPOSE

The purpose of this study was to evaluate potential differences in volumes of areas of osteolysis caused by medication-related osteonecrosis of the jaw (MRONJ) between the upper and lower jaw. We aim to analyze the clinical relevance of volumetric measurement of osteolytic lesions for surgical planning of MRONJ patients.

METHODS

Sixty-seven patients who were clinically and histopathologically diagnosed with MRONJ were retrospectively included in this study. Cone beam computed tomography (CBCT) images were evaluated according to localization, affected anatomical structures, and volumetric measurement of osteolytic lesions caused by MRONJ in appliance of CBCT datasets by using ITK-SNAP.

RESULTS

The most frequently affected localization is the mandible, whereas female patients show significantly more often lesions of the maxilla. The cortical bone was predominantly affected. Furthermore, the affection of teeth, sinus floor, inferior alveolar nerve canal, or even a pathological fracture of the mandible are infrequently existing. The volumetric measurements revealed a statistically significant greater absolute osteolysis volume in males.

CONCLUSIONS

Image analysis and volumetric measurements of osteolytic lesions of MRONJ patients is a helpful tool to further understand the clinical appearance and identify compromised anatomic landmarks. Volumetric analysis aids in pre-surgical planning and visualizes the individual extent of the disease for each patient.

A literature review of perioperative antibiotic administration in surgery for medication-related osteonecrosis of the jaw

PURPOSE

Few studies exist that focus on the details of perioperative antibiotic administration for surgery to treat medication-related osteonecrosis of the jaw (MRONJ). The regime and duration of perioperative antibiotics applied in published studies were reviewed to clarify appropriate perioperative antibiotic use in MRONJ surgery.

METHODS

A literature search was conducted using the MEDLINE database via PubMed.

RESULTS

The search resulted in 453 hits on PubMed. After reading the downloaded full-text articles, 17 articles met the inclusion and exclusion criteria. The most common perioperative antibiotic used for MRONJ surgery was a combination of penicillin-based antibiotics and β-lactamase inhibitor (52.9%), and the second most common regime was penicillin-based antibiotics with metronidazole (17.6%). The duration of administration was 2 weeks postoperatively in nine studies, whereas four studies applied long-term administration (2-6 weeks postoperatively).

CONCLUSIONS

Oral and maxillofacial surgeons mostly prefer penicillin-based antibiotics plus β-lactamase inhibitor or metronidazole for MRONJ surgery. The duration of administration of these medications may be based on empirical experience.

Microbial diversity in infections of patients with medication-related osteonecrosis of the jaw

OBJECTIVES

A central role of infections in the treatment of MRONJ patients is widely accepted. An investigation of the MRONJ lesions' biofilms as potential pathogens seems logical.

MATERIALS AND METHODS

We investigated the clinical data of our MRONJ patients who received surgery in advanced stage of the disease. Special attention was granted to the local colonizers harvested from osseous MRONJ specimens and submucosal putrid infections.

RESULTS

Eleven out of 71 patients presented a spontaneous onset of the disease and for 60 out of 71 patients a trigger was detected. Breast cancer (29.6%) and prostate cancer (22.5%) were the most frequent underlying disease for prescription of an antiresorptive therapy, mostly zoledronate. Submucosal soft tissue biofilms significantly differed from biofilms harvested from the MRONJ lesions bottom, yet the most frequent bacteria were equally present in both groups: Streptococcus species (spp.), Prevotella spp., Actinomyces spp., Veillonella spp., and Parvimonas micra. The cephalosporins, cefuroxime and cefotaxime, and ß-lactam antibiotics with ß-lactamase inhibitor revealed the greatest susceptibility for the detected bacteria.

CONCLUSION

The bacteria from the submucosal areas and the bottom of the infected bone presented comparable susceptibility to the common antibiotics regimes. Streptococcus spp., Prevotella spp., and Veillonella spp. present a high abundance in MRONJ lesions beside Actinomyces spp. The MRONJ lesions bottom is in many cases not infected by Actinomyces spp.

CLINICAL RELEVANCE

The removal of the necrotic bone reduces the variety of bacteria found in MRONJ lesions, in particular at the bottom of the lesion.

Relevant factors for treatment outcome and time to healing in medication-related osteonecrosis of the jaws - A retrospective cohort study

BACKGROUND

Risk factors for medication-related osteonecrosis of the jaw (MRONJ) are well known, although few studies evaluate the factors that influence treatment outcomes in MRONJ and whether discontinuing antiresorptive medication influences healing.

PURPOSE

(1) Describe the characteristics of a population of patients with MRONJ. (2) Identify the factors associated with favourable outcomes. (3) Identify a temporal correlation between discontinuation of antiresorptives and healing time.

METHODS

A retrospective longitudinal cohort study was carried out, including 77 patients with MRONJ treated between 2004 and 2016. Primary outcome was defined as healed/improved vs. worse/stable. Time to healing was set as the secondary outcome. Statistical significance was defined as p < 0.05.

RESULTS

Primary disease, route of administration, lesion location, and development of complications influenced the outcome of treatment. Significant differences in outcomes according to primary disease (p < 0.05) were found when staging, gender, and lesion location were held constant. Time to healing was longer for patients who discontinued medication more than 3 months after diagnosis than for those who discontinued at diagnosis or before - respectively, 36, 9, and 7 months (p = 0.01).

CONCLUSIONS

The outcome of MRONJ treatment may be influenced by primary disease and route of administration of antiresorptives. Antiresorptive medication discontinuation contributes to reduce healing time in MRONJ.