O papel da infecção e inflamação na etiopatogênese da osteonecrose dos maxilares induzida por medicamentos / The role of infection and inflammation in the etiopathogenesis of medication-related osteonecrosis of the jaw

Objetivo: O objetivo desta revisão de literatura é evidenciar o papel da infecção e inflamação na etiopatogenia da osteonecrose dos maxilares induzida por medicamentos (MRONJ). Revisão da literatura: A MRONJ é uma condição rara e grave que impacta negativamente a vida dos pacientes afetados. Sua etiopatogenia é multifatorial e ainda não foi totalmente compreendida. Uma das hipóteses propostas para explicá-la sugere que, além da inibição do turnover ósseo pelos medicamentos antirreabsortivos, a infecção associada à exodontia e a inflamação local desempenham papel decisivo no desencadeamento da condição. O entendimento da etiopatogenia da MRONJ permite ao cirurgião-dentista a identificação dos pacientes com risco maior para a doença, assim como o auxilia no monitoramento e escolha do manejo mais adequado. No campo da pesquisa, ele pode aprimorar estudos pré-clínicos e aprofundar a investigação de biomarcadores para diagnóstico precoce de MRONJ. Considerações finais: Conhecer a contribuição da infecção e inflamação na etiopatogênese da MRONJ é fundamental para orientar a pesquisa e a adoção de estratégias preventivas para os pacientes em risco, e de manejo e monitoramento adequado para aqueles já acometidos. (AU)

Aim: The aim of this literature review is to highlight the role of infection and inflammation in the etiopathogenesis of drug-induced osteonecrosis of the jaw (MRONJ). Literature review: MRONJ is a rare and serious condition that negatively impacts the lives of affected patients. Its etiopathogenesis is multifactorial and has not yet been fully understood. One of the hypotheses proposed to explain it suggests that, in addition to the inhibition of bone turnover by antiresorptive drugs, the infection associated with tooth extraction and local inflammation play a decisive role in triggering the condition. Understanding the etiopathogenesis of MRONJ allows the dentist to identify patients at higher risk for the disease, as well as assisting in monitoring and choosing the most appropriate management. In research, it can improve preclinical studies and deepen the investigation of biomarkers for early diagnosis of MRONJ. Conclusion: Knowing the contribution of infection and inflammation in the etiopathogenesis of MRONJ is essential to guide research and the adoption of preventive strategies for patients at risk, and adequate management and monitoring for those already affected.(AU)

Osteonecrose dos maxilares relacionada ao uso demedicamentos: características patológicas, diagnóstico,prevenção e estratégias terapêuticas / Medication-related osteonecrosis of the jaws: pathological characteristics, diagnosis, prevention and therapeutic strategies

Objetivo: Este trabalho tem como propósito fornecer uma análise abrangente das características clínicas, etiológicas, radiográficas e histopatológicas da osteonecrose dos maxilares relacionada ao uso de medicamentos, além de abordar os métodos de diagnóstico, prevenção e estratégias terapêuticas. Materiais e métodos: foi realizada uma busca por artigos científicos publicados no período de 2015 a 2023, utilizando as bases de dados Scientific Electronic Library Online (SciELO), US National Library of Medicine (PubMed) e ScienceDirect. Conclusão: Embora infrequente, há um considerável potencial de ocorrência de osteonecrose dos maxilares em pacientes submetidos a terapia prolongada com medicamentos antirreabsortivos e antiangiogênicos, especialmente quando não são adotadas medidas preventivas adequadas. A implementação de práticas preventivas, a vigilância das condições bucais e a colaboração de uma equipe multidisciplinar são fundamentais para reduzir os riscos associados a essa condição patológica.(AU)

Objective: This work aims to provide a comprehensive analysis of the clinical, etiological, radiographic and histopathological characteristics of Medication-Related Jaw Osteonecrosis, in addition to addressing diagnostic methods, prevention and therapeutic strategies. Materials and methods: A search was carried out for scientific articles published between 2015 and 2023, using the Scientific Electronic Library Online (SciELO), US National Library of Medicine (PubMed) and ScienceDirect databases. Conclusion: Although infrequent, there is a considerable potential for osteonecrosis of the jaw to occur in patients undergoing prolonged therapy with antiresorptive and antiangiogenic medications, especially when adequate preventive measures are not adopted. The implementation of preventive practices, surveillance of oral conditions and the collaboration of a multidisciplinary team are essential to reduce the risks associated with this pathological condition.(AU)

Histological Evaluation of the Effect of Alendronate on the Maxillary Bone of Wistar Rats Combined with Orthodontic Movement of Intense Force / Evaluación Histológica del Efecto del Alendronate en el Hueso Maxilar de Ratas Wistar Combinado con Movimiento de Ortodoncia de Fuerzas Intensas

SUMMARY: To evaluate the histological adverse effects of alendronate administered systemically and topically in combination with orthodontic movement by intense force. Thirty-six 24-week-old female Wistar rats, ovariectomized, were used and divided into three groups (n = 12/group): control, locally treated with saline (0.07 ml/kg/week) (group 1) and experimental, treated with alendronic acid systemically (0.07 mg/kg/week) (group 2) and locally (7 mg/kg/week) (group 3). At 14 days, an orthodontic anchor was installed in the right first molar, and a force of 144 cN was applied for 28 days. The samples were processed for histological evaluation. Descriptive statistics, Shapiro-Wilk tests, one-way ANOVA with Bonferroni correction, one-way repeated measures ANOVA and chi-square tests were performed. All tests were statistically significant at p <0.05. The adverse events found in all groups were inflammation and osteoclastic activity. In the bisphosphonate-treated groups, there were statistically significant differences (p = 0.005) in the osteoclastic activity between the two hemiarcates. All rats in group 2 presented paralytic ileus. Compared to local administration, systemic treatment with alendronic acid produces more adverse effects, such as inflammation, fibrinoid necrosis, and osteoclastic activity. During the application of intense forces, it was not possible to show that there is necrosis associated with bisphosphonates.

Evaluar los efectos adversos histológicos del alendronato administrado sistémica y tópicamente en combinación con movimientos ortodóncicos de fuerza intensa. Treinta y seis ratas Wistar hembras de 24 semanas de edad, ovariectomizadas, fueron utilizadas y divididas en tres grupos (n = 12/grupo): control, tratado localmente con solución salina (0,07 ml/kg/semana) (grupo 1) y experimental, tratados con ácido alendrónico por vía sistémica (0,07 mg/kg/semana) (grupo 2) y local (7 mg/kg/semana) (grupo 3). A los 14 días se instaló un anclaje de ortodoncia en el primer molar derecho y se aplicó una fuerza de 144 cN durante 28 días. Las muestras fueron procesadas para evaluación histológica. Se realizó estadística descriptiva, pruebas de Shapiro-Wilk, ANOVA de una vía con corrección de Bonferroni, ANOVA de medidas repetidas de una vía y pruebas de chi-cuadrado. Todas las pruebas fueron estadísticamente significativas con un p <0,05. Los eventos adversos encontrados en todos los grupos fueron inflamación y actividad osteoclástica. En los grupos tratados con bisfosfonatos hubo diferencias estadísticamente significativas (p = 0,005) en la actividad osteoclástica entre los dos hemiarcados. Todas las ratas del grupo 2 presentaron íleo paralítico. En comparación con la administración local, el tratamiento sistémico con ácido alendrónico produce más efectos adversos, como inflamación, necrosis fibrinoide y actividad osteoclástica. Durante la aplicación de fuerzas intensas, no fue posible demostrar que existe necrosis asociada con los bisfosfonatos.

Osteonecrosis maxilar inferior asociado a bifosfonatos / Lower jaw osteonecrosis associated with bisphosphonates / Osteonecrose do maxilar inferior associada a bisfosfonatos

Introducción: dada la alta prescripción de bifosfonatos, presentamos sus efectos adversos en la esfera odontológica, siendo una complicación poco frecuente, pero de difícil tratamiento. Sin necesidad de suspender el tratamiento, dado el importante beneficio en cuanto a la prevención de fractura por fragilidad. Estas fracturas causan una alta morbimortalidad en contraposición al bajo riesgo que conlleva la Osteonecrosis mandibular asociada a bifosfonatos. Objetivo: orientar al personal de salud que maneja estos fármacos y quien asiste dichas complicaciones a poseer conocimientos para la prevención de osteonecrosis. Identificar y diferenciar los pacientes con mayor riesgo, de acuerdo con la dosis de bifosfonatos y la frecuencia del tratamiento. Materiales y Método: se realizó una revisión bibliográfica en las siguientes fuentes: Scielo, Google académico, Medline/Pubmed, Biblioteca Virtual en Salud (Brasil), desde el año 2005 a la fecha, idiomas español, portugués e inglés. Los descriptores utilizados son bifosfonatos, mandíbula, maxilar, odontología, osteonecrosis, osteonecrosis de los maxilares asociada a bifosfonatos. Resultados: las últimas pautas de tratamiento fueron modificadas en 2014, por consenso de la Asociación Americana de cirugía Oral y Maxilofacial. La patogénesis de la osteonecrosis maxilar asociada a bifosfonatos no está completamente definida, aunque las publicaciones tratan de explicarla. El riesgo de desarrollarla por terapia oral es menor que por su administración vía intravenosa. Discusión: el médico que prescribe el antirresortivo debe conocer el estado de salud dental de su paciente y, en lo posible, remitirlo a examen con el odontólogo antes de iniciar la terapia con bifosfonatos.

Introduction: Given the high prescription of bisphosphonates, we present their adverse effects in the dental sphere, being an infrequent complication, but difficult to treat. There is no need to suspend treatment, given the important benefit in terms of prevention of fragility fractures. These fractures cause high morbimortality as opposed to the low risk associated with bisphosphonate-associated osteonecrosis of the jaw. Objective: To orient the health personnel who handle these drugs and who assist these complications to have knowledge for the prevention of osteonecrosis. To identify and differentiate patients at higher risk, according to the dose of bisphosphonates and frequency of treatment. Materials and Method: A literature review was performed in the following sources: Scielo, Google academic, Medline/Pubmed, Virtual Health Library (Brazil), from 2005 to date, Spanish, Portuguese and English languages. The descriptors used were bisphosphonates, mandible, maxilla, dentistry, osteonecrosis, osteonecrosis of the jaws associated with bisphosphonates. Results: The latest treatment guidelines were modified in 2014, by consensus of the American Association of Oral and Maxillofacial Surgery. The pathogenesis of bisphosphonate-associated maxillary osteonecrosis is not completely defined, although publications try to explain it. The risk of developing it by oral therapy is lower than by intravenous administration. Discussion: The physician who prescribes the antiresorptive drug should know the dental health status of his patient and, if possible, refer him for examination by a dentist before initiating bisphosphonate therapy.

Introdução: dada a alta prescrição de bisfosfonatos, apresentamos seus efeitos adversos na esfera odontológica, uma complicação rara, mas de difícil tratamento. Sem a necessidade de suspender o tratamento, dado o importante benefício em termos de prevenção de fraturas por fragilidade. Essas fraturas causam alta morbidade e mortalidade, em contraste com o baixo risco associado à osteonecrose da mandíbula associada aos bisfosfonatos. Objetivo: orientar a equipe de saúde que manipula esses medicamentos e que atende a essas complicações para que tenham conhecimento sobre a prevenção da osteonecrose. Identificar e diferenciar os pacientes de maior risco, de acordo com a dose de bisfosfonatos e a frequência do tratamento. Materiais e Método: foi realizada uma revisão da literatura nas seguintes fontes: Scielo, Google acadêmico, Medline/Pubmed, Biblioteca Virtual em Saúde (Brasil), de 2005 até a presente data, idiomas espanhol, português e inglês. Os descritores utilizados foram: bisfosfonatos, mandíbula, maxila, odontologia, osteonecrose, osteonecrose dos maxilares associada a bisfosfonatos. Resultados: as diretrizes de tratamento mais recentes foram modificadas em 2014, por consenso da Associação Americana de Cirurgia Oral e Maxilofacial. A patogênese da osteonecrose da mandíbula associada a bisfosfonatos não está totalmente definida, embora a literatura tente explicá-la. O risco de desenvolvê-la com a terapia oral é menor do que com a administração intravenosa. Discussão: o médico que prescreve o medicamento deve estar ciente do estado de saúde bucal do paciente e, se possível, encaminhar o paciente para ser examinado por um dentista antes de iniciar a terapia com bisfosfonatos.

Osteonecrosis maxilar asociada con altas dosis de antirresortivos en paciente oncolólgico adulto mayor: resolución interdisciplinaria de caso clínico / Osteonecrosis of the jaw associated with high doses of antiresorptive in an elderly cancer patient: interdisciplinary resolution of a clinical case

La osteonecrosis maxilar relacionada con medicamentos (ONMM) es una patología de características clínicas objetivas con signo-sintomatología patogno-mónica. El criterio clínico aceptado es la presencia de hueso necrótico expuesto y visible sobre el reborde óseo maxilar que no ha cicatrizado luego de 8 sema-nas, en pacientes con antecedentes de tratamiento antirresortivo. La denominación relacionada con medicamentos se utiliza por el creciente número de casos asociados con otros fármacos antirresortivos como denosumab y con terapias antiangiogénicas, más allá de la conocida relación con bifosfonatos. Si bien la incidencia de ONMM en pacientes tratados por osteopatías metabólicas es muy baja, la situa-ción se torna más compleja en pacientes oncológicos con altas dosis de antirresortivos para tratamiento de metástasis ósea. Varios informes de casos des-criben cuadros de ONMM en pacientes con cáncer que reciben terapias dirigidas, específicamente TKI (inhibidores de tirosina kinasa) y anticuerpos mo-noclonales-VEGF (anticuerpos dirigidos al factor de crecimiento del endotelio vascular). La ONMM afecta negativamente la calidad de vida del paciente onco-lógico y produce comorbilidad significativa. Resulta imperioso identificar los pacientes en riesgo y dise-ñar un protocolo de atención odontológica específico para estos casos. En este artículo, se presenta un caso de ONMM asociado con altas dosis de Deno-sumab y administración simultánea de anticuerpos monoclonales específicos. El caso sorprende por la magnitud de la necrosis y su cuadro insidioso. El pro-tocolo de tratamiento descripto permitió controlar el cuadro inicial, limitar el avance de la lesión, asegurar el control del dolor y la infección, y finalmente, la cu-ración total de la lesión (AU)

Medication-related osteonecrosis of the jaws (MRONJ) is a pathology with objective clinical characteristics with pathognomonic signs and symp-toms. The accepted clinical criterion is the presence of exposed and visible necrotic bone on the maxillofacial region that has not healed after 8 weeks, in patients with history of antiresorptive treatment. The name medication-related is justified by the growing number of cases associated with other antiresorptive drugs such as denosumab and antiangiogenic therapies, beyond the known relationship with bisphosphonates. Although the incidence of MRONJ in patients treated for metabolic osteopathies is very low, the situation becomes more complex in cancer patients who re-ceive high doses of antiresorptives for the treatment of skeletal metastases. Several case reports describe the presence of MRONJ in cancer patients receiving targeted therapies, specifically TKI (tyrosine kinase inhibitors) and monoclonal antibodies-targeting VEGF (vascular endothelial growth factor). MRONJ nega-tively affects the quality of life in cancer patients and produces significant comorbidity. It is imperative to identify patients at risk and design a specific den-tal care strategy for these cases. In this article, we present a case of MRONJ associated with high doses of Denosumab and simultaneous administration of specific monoclonal antibodies. The case is surpris-ing due to magnitude of the necrosis. The described treatment strategies made it possible to control the initial symptoms, limit the lesion progression, ensure pain and infection control, and finally, the total heal-ing of the lesion (AU)

Osteonecrosis de los maxilares: reacción medicamentosa / Osteonecrosis of the jaws: drug reaction

La osteonecrosis de los maxilares (ONM) secundaria al consumo de medicamentos antirresortivos y antiangiogénicos es una patología oral que afecta el funcionamiento del organismo de los seres humanos no sólo a nivel bucal, sino que disminuye su calidad de vida y aumenta su morbilidad. La ONM se define como la presencia de hueso necrótico expuesto que puede ser explorado mediante una fístula en el territorio maxilofacial, que se mantiene durante un periodo mínimo de ocho se- manas. Los fármacos antirresortivos y antiangiogénicos son indicados a pacientes que presentan patologías osteometabólicas, cáncer, entre otras, de ahí la importancia de mantener una estrecha relación entre médico tratante-odontólogo-paciente. El propósito de este artículo es establecer un protocolo de cuidado oral básico y definir las funciones del médico tratante, cirujano dentista y cirujano maxilofacial mediante una revisión bibliográfica con el fin de crear una propuesta preventiva para el tratamiento de estos pacientes (AU)

Medication-related osteonecrosis of the jaw (MRONJ), secondary to the consumption of antiresorptive and antiangiogenic drugs is an oral pathology that affects the functioning of the human body, not only at the oral level, but also decreasing their quality of life and increasing their morbidity. MRONJ is defined as the presence of exposed necrotic bone that can be explored through a fistula in the maxillofacial territory, which is maintained for a minimum period of eight weeks. Antiresorptive and antiangiogenic drugs are indicated for patients with osteometabolic pathologies, cancer, among others. For the same reasons, the importance of maintaining a close relationship between the treating physician, dentist and patient. The purpose of this article is to establish a clinical guide for basic oral care and define the functions of the treating physician, dental surgeon and maxillofacial surgeon through a bibliographic review; in order to create a preventive proposal for the treatment of these patients (AU)

Osteonecrosis de los maxilares asociada a drogas antirresortivas en pacientes osteoporóticos: presentación de un caso clínico / Antiresorptive drugs-related jaw osteonecrosis in osteoporotic patients: report of a clinical case

La osteoporosis se caracteriza por una masa ósea baja con deterioro de la microarquitectura del tejido que conduce a la fragilidad, lo que aumenta el riesgo de fracturas. Después de la menopausia, la deficiencia de estrógenos aumenta la exposición del tejido al ligan- do RANK, lo que resulta en un aumento de la reabsorción y pérdida ósea, que pueden provocar osteoporosis. (1) Los bifosfonatos y el denosumab son utilizados para el tratamiento de la osteoporosis debido a su capacidad anticatabólica, que reducen la remodelación previniendo la pérdida de masa ósea, disminuyendo la probabilidad de fracturas y aumentando la densidad mineral del tejido. (2) La osteonecrosis de los maxilares asociadas a drogas antirresortivas es una situación que se presenta en pacientes que consumen de manera crónica antirresortivos para el tratamiento de enfermedades como: osteoporosis, osteogénesis imperfecta, enfermedad de Paget, displasia fi- brosa, hipercalcemia maligna asociada a tratamiento oncológico (AU)

Osteoporosis is characterized by low bone mass with deterioration of the tissue microarchitec- ture leading to fragility, which increases the risk of fractures. After menopause, estrogen deficiency increases tissue exposure to the RANK ligand, resulting in increased bone loss and resorption, which can lead to osteoporosis. (1) Bisphosphonates and denosumab are used for the treatment in low concentration, due to their anticatabolic capacity, which reduce remodeling, preventing loss of bone mass and fractures besides, antiresorptives drugs increase the mineral density of the tissue. (2) Osteonecrosis of the jaw associated with antiresorptives drugs occurs in patients whose chro- nically consume these drugs for the treatment of diseases such as: osteoporosis, imperfect osteogenesis, Paget's disease, fibrous dysplasia, malignant hypercalcemia associated with oncological treatment (AU)

Interpretation of medication-related osteonecrosis of the jaw: MASCC/ISOO/ASCO clinical practice guideline / 中华口腔医学杂志

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse event related to administration of antiresorptive or antiangiogenic medications. With the increasing usage of bone-modifying agents in cancer therapy, the incidence of MRONJ enhanced gradually, which affects the life quality of patients and interferes with cancer therapy. In 2019, Multinational Association of Supportive Care in Cancer (MASCC), International Society of Oral Oncology (ISOO) and American Society of Clinical Oncology (ASCO) convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations on practices in the prevention and management of MRONJ in patients with cancer. The present article made an interpretation of Medication-Related Osteonecrosis of the Jaw: MASCC/ISOO/ASCO Clinical Practice Guideline so as to provide clinicians with diagnostic and therapeutic approaches for cancer patients with MRONJ.

Denosumab como tratamiento neoadyuvante del tumor de células gigantes del hueso. Indicaciones, resultados y efectos adversos / Denosumab as a neoadjuvant treatment for giant cell tumor of bone. Indications, results and side effects

Resumen El tumor de células gigantes óseo es una neoplasia de agresividad local intermedia, que raramente metastatiza. En los últimos años el denosumab, anticuerpo monoclonal humano, surgió como una alternativa de tratamiento para esta enfermedad, al bloquear el comportamiento lítico tumoral. El objetivo de este trabajo fue determinar sus indicaciones y efectos adversos, analizando también los resultados oncológicos, y las tasas de recurrencia local en pacientes con diagnóstico de tumor de células gigantes óseo que recibieron denosumab como tratamiento neoadyuvante. Entre 2010 y 2018 se analizaron 80 pacientes con tumor de células gigantes, de los cuales 14 recibieron denosumab como tratamiento neoadyuvante. El seguimiento mínimo fue 12 meses. En 8 pacientes se trató de un tumor primario, mientras que 6 fueron pacientes con recidiva tumoral. En todos los casos se evidenció una mejoría clínica. Trece presentaron cambios radiográficos, y 11 respuesta histológica completa. En 6 de 14 pacientes se evidenció una recurrencia local y en 7 se identificó al menos un efecto adverso relacionado con el denosumab (incluyendo una malignización tumoral). A pesar de ser una herramienta útil para el tratamiento del tumor de células gigantes, el uso de denosumab está asociado a mayor tasa de recurrencias locales y no está exento de efectos adversos.

Abstract Giant cell tumor of bone is an intermediate, locally aggressive and rarely metastasiz ing, primary bone neoplasia. In recent years denosumab emerged as a treatment alternative for this pathology. The objective of this work was to analyze its indications as well as the clinical outcomes, side effects and local recurrence rates in patients diagnosed with giant cell tumor of bone, who received denosumab as neoadjuvant treatment. Between 2010 and 2018, 80 patients with giant cell tumor were analyzed, of whom 14 received deno sumab as a neoadjuvant treatment. The minimum follow-up was 12 months. In 8 patients it was a primary tumor, while 6 showed tumor recurrence. In all cases, clinical improvement was evident. Thirteen patients presented radiographic changes, and 11 showed complete histological response. A local recurrence was evidenced in 6 of 14 patients, and at least one adverse effect related to denosumab (including tumor malignancy) was identified in 7. Despite being a useful tool for treating giant cell tumor, the use of denosumab is associated with a higher rate of local recurrences and is not free of adverse effects.

Osteonecrosis maxilar relacionada con medicamentos en pacientes oncológicos con metástasis óseas: resolución de dos casos / Medication-related osteonecrosis of the jaw in oncological patients with bone metastases: resolution of two cases

La osteonecrosis maxilar relacionada con medicamentos (ONMM) es una patología de características clínicas objetivas con signo-sintomatología patognomónica. El criterio clínico aceptado es la presencia de hueso necrótico expuesto y visible sobre el reborde óseo maxilar que no ha cicatrizado luego de 8 semanas, en pacientes con antecedentes de tratamiento antirresortivo. La denominación "relacionada con medicamentos" se utiliza por el creciente número de casos asociados con otros fármacos antirresortivos como denosumab y con terapias antiangiogénicas, más allá de la conocida relación con bifosfonatos.Si bien la incidencia de ONMM en pacientes tratados por osteopatías metabólicas es muy baja, la situación se torna más compleja en pacientes oncológicos con altas dosis de antirresortivos para tratamiento de metástasis ósea. Varios in-formes de casos describen cuadros de ONMM en pacientes con cáncer que reciben terapias dirigidas, específicamente TKI (inhibidores de tirosina quinasa) y anticuerpos monoclonales-VEGF (anticuerpos dirigidos al factor de crecimiento del endotelio vascular). La ONMM afecta negativamente la calidad de vida del paciente oncológico y produce comorbilidad significativa. Resulta imperioso identificar a los pacientes en riesgo y diseñar un protocolo de atención odontológica específico para estos casos. En este artículo se presentan dos casos de ONMM asociado con altas dosis de denosumab y administración simultánea de anticuerpos monoclonales específicos para el tratamiento del cáncer. Ambos casos sorprenden por la prematura instalación de la necrosis y su cuadro insidio-so. El protocolo de tratamiento descripto permitió controlar el cuadro inicial, limitar el avance de la lesión, asegurar el control del dolor y la infección, y finalmente, la curación total de la lesión. (AU)

Medication-related osteonecrosis of the jaws (MRONJ) is a pathology with objective clinical characteristics, with pathognomonic signs and symptoms. The accepted clinical criterion is the presence of exposed and visible necrotic bone on the maxillofacial region that has not healed after 8 weeks, in patients with history of antiresorptive treatment.The name "medication-related" is justified by the growing number of cases associated with other antiresorptive drugs such as denosumab and antiangiogenic therapies, beyond the known relationship with bisphosphonates. Although the incidence of MRONJ in patients treated for metabolic osteopathies is very low, the situation becomes more complex in cancer patients who receive high doses of antiresorptives for the treatment of skeletal metastases. Several case reports describe the presence of MRONJ in cancer patients receiving targeted therapies, specifically TKI (tyrosine kinase inhibitors) and monoclonal antibodies-targeting VEGF (vascular endothelial growth factor). MRONJ negatively affects the quality of life in cancer patients and produces significant comorbidity. It is imperative to identify patients at risk and design a specific dental care strategy for these cases.In this article, we present two cases of MRONJ associated with high doses of Denosumab and simultaneous administration of specific monoclonal antibodies. Both cases are surprising due to premature onset of necrosis. The described treatment strategies made it possible to control the initial symptoms, limit the lesion progression, ensure pain and infection control, and finally, the total healing of the lesion. (AU)

Osteonecrosis asociada a pacientes con consumo de antirresortivos bajo tratamiento oncológico / Osteonecrosis associated to patients who take anti-resorptive drugs, undergoing oncologic treatment

La Asociación Americana de Cirugía Oral y Maxilofacial (American Association of Oral and Maxillofacial Surgeons [AAOMS]): define el concepto de osteonecrosis maxilar asociada a drogas antirresortivas (MRONJ) como: «área ósea necrótica expuesta al medio bucal con más de ocho semanas de permanencia, en presencia de tratamiento crónico con bifosfonatos en ausencia de radioterapia en cabeza y cuello¼. El objetivo de este artículo es asociar la enfermedad oncológica en relación con las drogas antirresortivas consumidas por pacientes, la prescripción de dichas drogas y el depósito de ellas en el organismo. Al mismo tiempo, la interacción médico-odontológico debe implementarse en favor de la salud de nuestros pacientes (AU)

American Association of Oral and Maxillofacial Surgeons AAOMS defined Medication Related of the Jaw (MRONJ) as «necrotic bone area exposed to the oral environment with more than eight weeks of permanence, in the presence of chronic treatment with BPs, in the absence of radiation therapy to the head and neck¼. The objective of this article is associate oncology antiresorptives treatments prescribed by physicians, their prescription and body accumulation in patients whose are treated with them. Interdisciplinary dental and physician clinical treatments must be implemented in patient favours (AU)

Expert consensus on safety management of bone-modifying agents / 中华肿瘤杂志

Bone-modifying agents currently include bisphosphonates and desumumab, which are the main drugs for the treatment of malignant tumor bone metastasis, hypercalcemia and osteoporosis. Due to its wide clinical application, the adverse events of this kind of drugs are gradually increasing and affecting the quality of life of patients. Therefore, it needs to arouse the attention of the majority of medical personnel. Based on the substantial evidence, the expert committee has thoroughly discussed the management of adverse reactions of bone modifying agents and put forward reasonable suggestions, to guide clinicians in the safety management of such drugs.

Prevention and treatment of oral adverse effects of antiresorptive medications for osteoporosis - A position paper of the Brazilian Society of Endocrinology and Metabolism (SBEM), Brazilian Society of Stomatology and Oral Pathology (Sobep), and Brazilian Association for Bone Evaluation and Osteometabolism (Abrasso)

ABSTRACT Antiresorptive therapy is the main form of prevention of osteoporotic or fragility fractures. Medication-related osteonecrosis of the jaw (MRONJ) is a relatively rare but severe adverse reaction to antiresorptive and antiangiogenic drugs. Physicians and dentists caring for patients taking these drugs and requiring invasive procedures face a difficult decision because of the potential risk of MRONJ. The aim of this study was to discuss the risk factors for the development of MRONJ and prevention of this complication in patients with osteoporosis taking antiresorptive drugs and requiring invasive dental treatment. For this goal, a task force with representatives from three professional associations was appointed to review the pertinent literature and discuss systemic and local risk factors, prevention of MRONJ in patients with osteoporosis, and management of established MRONJ. Although scarce evidence links the use of antiresorptive agents in the context of osteoporosis to the development of MRONJ, these agents are considered a risk factor for this complication. Despite the rare reports of MRONJ in patients with osteoporosis, the severity of symptoms and impact of MRONJ in the patients' quality of life make it imperative for health care professionals to consider this complication when planning invasive dental procedures.

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

ABSTRACT BACKGROUND: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is still the most prevalent type of osteonecrosis with clinical relevance. In Brazil, bisphosphonate use is high but there is a lack of epidemiological studies on BRONJ. OBJECTIVE: To determine the clinical profile of BRONJ in a Brazilian population through an integrative review. DESIGN AND SETTING: Integrative review of BRONJ in a Brazilian population. METHODS: Cases and clinical research on Brazilians with BRONJ between 2010 and 2019, indexed in PubMed/MEDLINE, Scopus, Web of Science and LILACS were reviewed. Age, sex, type and time of bisphosphonate intake, administration route, related diseases, region of the BRONJ, diagnostic criteria, staging, triggering factor and type of treatment were analyzed. RESULTS: Fifteen articles on 128 subjects were included. Most patients were women (82.03%); the mean age was 63 years. Intravenous zoledronic acid was mostly used (62.50%), for breast cancer treatment (46.87%). The main localization of BRONJ was the mandible (54.68%), associated mainly with tooth extractions (45.98%). The diagnostic criteria were clinical (100%) and radiographic (89.06%), mostly in stage II (68.08%). The surgical treatments were sequestrectomy (37.50%) and platelet-rich plasma (PRP) (36.71%). Microbial control was done using chlorhexidine (93.75%) and infection control using clindamycin (53.90%). CONCLUSIONS: BRONJ had higher prevalence in Brazilian women receiving treatment for breast cancer and osteoporosis. The mandible was the region most affected with a moderate stage of BRONJ, particularly when there were histories of tooth extraction and peri-implant surgery. Sequestrectomy with additional drugs and surgical therapy was the treatment most accomplished.

Delayed alveolar bone repair and osteonecrosis associated with Zoledronic Acid therapy in rats: macroscopic, microscopic and molecular analysis

Abstract Objective This study aims to evaluate bone repair and the development of the medication related osteonecrosis of the jaw (MRONJ) associated with the use of zoledronic acid in Wistar rats. Methodology 48 male Wistar rats were divided into four groups: ZA, treated with intraperitoneal zoledronic acid, 0.6 mg/kg every 28 days, totaling five doses; control (C), treated with 0.9% sodium chloride; ZA-surgical (SZA) and C-surgical (SC), submitted to extraction of the right upper molars 45 days after the first application. Alveolar bone repair was evaluated by macroscopic and histological analysis. Protein expression evaluations were performed by qPCR. Results Macroscopic evaluation showed that 91.66% (11) of the animals in the SZA group and 41.66% (5) from the SC group presented solution of epithelium continuity (P<0.05). All animals in the SZA group and none in the SC group had bone sequestration. The area of osteonecrosis was higher in the SZA group than in the SC group (P<0.05). In molecular evaluation, the SZA group presented changes in the expression of markers for osteoclasts, with increased RANK and RANKL, and a decrease in OPG. Conclusion The results highlighted strong and evident interference of zoledronic acid in bone repair of the socket, causing osteonecrosis and delayed bone remodeling.

Pathogenesis and multidisciplinary management of medication-related osteonecrosis of the jaw / 国际口腔科学杂志·英文版

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

Atypical femoral fracture, case report and literature review / Fractura atípica del fémur, reporte de caso y revisión de la literatura

Abstract: Introduction: Bisphosphonates have been the gold standard in the management of osteoporosis. Its antiresorptive effect has reduced the incidence of fractures due to bone fragility, as well as its impact on public health. We present the clinical case of a patient in prolonged treatment with bisphosphonates and atypical bilateral femur fracture. Case report: A 65-year-old female who presented a fall from her own height, on treatment with risedronate for seven years, and a history of systemic arterial hypertension and hypercholesterolemia, both with medical treatment. Diagnosed with bilateral atypical femoral fracture, treated with closed reduction internal fixation (CRIF) with intramedullary nailing, application of calcium citrate and teriparatide. Discussion: Multiple studies indicate that the benefit of using bisphosphonates for osteoporosis is higher than the risk of presenting atypical fractures.

Resumen: Introducción: Los bifosfonatos han sido de gran utilidad en el manejo de la osteoporosis. Su efecto antirresortivo ha disminuido la incidencia de fracturas por fragilidad ósea, así como, su impacto en salud pública. Presentamos el caso clínico de una usuaria en tratamiento prolongado con bifosfonatos y fractura atípica de fémur bilateral. Caso clínico: Femenino de 65 años, presenta caía de su plano de sustentación, en tratamiento con risedronato desde hace siete años y antecedente de hipertensión arterial sistémica e hipercolesterolemia, ambas con manejo médico. Diagnosticada con fractura bilateral de fémur, tratada con enclavado centro-medular, citrato de calcio y teriparatida. Discusión: Múltiples estudios refieren que el beneficio del uso de bifosfonatos en la prevención del riesgo de fracturas es mayor, aunque exista la posibilidad de presentar fracturas atípicas.

The efficacy of sustained-release chitosan microspheres containing recombinant human parathyroid hormone on MRONJ

Abstract Treatment of patients with bisphosphonate usage is a significant concern for oral surgeons because it interferes with jaw bone turnover and regeneration. In case of adverse effects manifesting related to bisphosphonate use, oral surgeons are usually treating and keep the patient's symptoms under control. In this study, we aimed to investigate a new treatment protocol for medication-related osteonecrosis of the jaw (MRONJ). This treatment protocol consisted of administering human parathyroid hormone (hPTH) loaded chitosan microspheres which were prepared by ionotropic gelation method or/and the prepared microspheres were suspended in a poloxamer gel. After in-vitro optimization studies, the efficacy of the chosen formulations was evaluated in-vivo studies. Zoledronic acid was administered daily to forty-eight adult female Sprague-Dawley rats, divided into four experimental groups, at a daily concentration of 0.11 mg/kg over three weeks to induce the MRONJ model. At the end of this period, maxillary left molar teeth were extracted. In the first group, the subjects received no treatment. In the negative control group, poloxamer hydrogel containing empty microspheres were immediately applied to the soft tissues surrounding the extraction socket. The treatment group-1 was treated with local injections of poloxamer hydrogel containing hPTH. The treatment group-2 was treated with a single local injection of poloxamer hydrogel containing hPTH-loaded chitosan microspheres. Both treatment groups received a total of 7 µg of hPTH at the end of the treatment protocol. Our study demonstrates successful attenuation of MRONJ through a local drug delivery system combined with hPTH, as opposed to previously attempted treatment strategies.

Prevención de osteonecrosis asociada a medicamentos y ensayo clínico multicéntrico, Facultad de Odontología, Universidad de Buenos Aires / Prevention of drug-related osteonecrosis and multicentric clinical trial, School of Dentistry, University of Buenos Aires

La osteonecrosis asociada a medicamentos (ONAM) es un efecto adverso poco frecuente pero potencialmente serio que afecta a pacientes que reciben o recibieron tratamiento con drogas antirresortivas o antiangiogénicas. A partir de una revisión narrativa de la literatura, el presente artículo aporta conceptos básicos e información actualizada acerca de incidencia, factores de riesgo y prevención de ONAM desde la perspectiva de la Práctica Basada en la Evidencia. Además pone en conocimiento a la comunidad profesional de la Facultad de Odontología de la Universidad de Buenos Aires acerca de las actividades de investigación clínica llevadas a cabo en este área en la Cátedra de Cirugía y Traumatología Buco-Máxilo-Facial I de nuestra casa de estudios (AU)

Medicine related osteonecrosis of the jaws (MRONJ) is a rare but potentially serious side effect experienced by patients receiving treatment with antiresorptive or antiangiogenic drugs. Through a narrative review of the literature, this paper provides basic concepts and updated data about incidence, risk factors and prevention of MRONJ from the Evidence Based Practice perspective. It also informs the professional community of the School of Dentistry of the University of Buenos Aires about the clinical research activities carried out in this area in the Oral and Maxillofacial Surgery I Department (AU)

Effects of Zoledronic Acid in Experimental Periapical Lesions in Rats: An Imaging and Histological Analysis

Abstract The aim of this study was to assess the imaging and histological features of experimental periapical lesions, including the adjacent alveolar bone, in rats under zoledronic acid treatment. The study used 40 male Wistar rats distributed into 8 groups of 5 animals each: G1: induction of periapical lesion (PL) and weekly intraperitoneal administration (WIPA) of saline solution (0.9% NaCl) for 4 weeks; G2: PL induction and WIPA of zoledronic acid (0.15 mg/kg/week) for 4 weeks; G3: PL induction and WIPA of saline solution for 8 weeks; G4: PL induction and WIPA of zoledronic acid for 8 weeks; G5:WIPA of saline solution for 4 weeks and subsequent PL induction; G6: WIPA of zoledronic acid for 4 weeks and subsequent PL induction; G7: WIPA of saline solution for 8 weeks and subsequent PL induction; G8: WIPA of zoledronic acid for 8 weeks and subsequent PL induction. The administration of zoledronic acid or saline solution continued after PL induction until the euthanasia. Thus, cone beam computed tomography and histological analysis were performed. Statistical analyzes were performed by ANOVA and Kruskal-Wallis test. Groups treated with zoledronic acid showed significantly smaller size of PL than the groups treated with 0.9% NaCl (p<0.05). PLs were formed by chronic inflammation ranging from mild to moderate, with no difference between groups. In all specimens, no mandibular necrosis was observed. In conclusion, the presence of PLs apparently does not represent an important risk factor for the development of bisphosphonate-related osteonecrosis of the jaws.

Resumo O objetivo deste estudo foi avaliar as características histológicas e de imagem de lesões periapicais experimentais, incluindo o osso alveolar adjacente, em ratos sob tratamento com ácido zoledrônico. O estudo utilizou 40 ratos Wistar, machos, distribuídos em 8 grupos de animais cada: G1: indução de lesão periapical (LP) e administração intraperitoneal semanal (AIS) de solução salina (NaCl 0.9%) por 4 semanas; G2: indução de LP e AIS de ácido zoledrônico (0,15 mg/kg/week) por 4 semanas; G3: indução de LP e AIS de solução salina por 8 semanas; G4: indução de LP e AIS de ácido zoledrônico por 8 semanas; G5- AIS de solução salina por 4 semanas e subsequente indução de LP; G6- AIS de ácido zoledrônico por 4 semanas e subsequente indução de LP; G7: AIS de solução salina por 8 semanas e subsequente indução de LP; G8: AIS de ácido zoledrônico por 8 semanas e subsequente indução de LP. A administração de ácido zoledrônico ou solução salina continuou após indução de LP até a eutanásia. Após isso, tomografia computadorizada de feixe cônico e análise histológica foram realizadas. Análises estatísticas foram realizadas por ANOVA e teste de Kruskal-Wallis. Os grupos tratados com ácido zoledrônico mostraram LPs significativamente menores que os grupos tratados com NaCl 0.9% (p <0.05). LPs eram formadas por inflamação crônica variando de leve a moderada, sem diferença entre os grupos. Em todos os espécimes, necrose mandibular não foi observada. Em conclusão, a presença de LPs aparentemente não representa um fator de risco importante para o desenvolvimento de osteonecrose relacionada ao uso de bisfosfonatos.