Analysis of the Degree of Information of Dental Surgeons about Antiresorptive Drugs According to the Time Since Graduation in Dentistry

ABSTRACT Objective: To determine the level of scientific information of dental surgeons who carry out their professional activities in Brazil about antiresorptive drugs and indicated pharmacological procedures aiming at the prevention of osteonecrosis of the jaws and the therapy of drug sequelae that may occur, considering the time since graduation in Dentistry. Material and Methods: This is a quantitative cross-sectional study in which 339 dentists were consulted using the virtual questionnaire containing topics of personal nature, elements contained in the anamnesis carried out and knowledge about antiresorptive drugs, including indications, adverse effects and treatments applied. Chi-square and Fisher's exact tests were performed to analyze associations of data described by absolute and relative frequencies with professionals' time since graduation. All analyses were performed using the R software, with a 5% significance level. Results: Those who revealed to have graduated for more than five years with the highest academic degree were those who demonstrated maximum knowledge of antiresorptive drugs or revealed that, somehow, they had information about them (p<0.05). Conclusion: Dental surgeons in Brazil who have more than five years since graduation have more scientific information about antiresorptive drugs and pharmacological procedures, which can positively contribute to the prevention of osteonecrosis of the jaws and treatment of drug sequelae that may occur.

Revisión Bibliográfica: Terapia Ósea en Cáncer de Próstata Resistente a la Castración / Literature Review: Bone Therapy in Castration Resistant Prostate Cancer

El presente trabajo es una revisión bibliográfica y actualización de los diferentes esquemas terapéuticos aprobados y en estudio, de la enfermedad con metástasis en hueso producto del cáncer de próstata avanzado con la condición de resistente a la castración. Aborda generalidades del cáncer de próstata, los mecanismos por los cuales se vuelve resistente a la castración, la aparición de metástasis óseas, la terapéutica enfocada en terapia antiresortiva, (bifosfonatos e inhibidor del Ligando RANK), radiofármacos, radioterapia y nuevas drogas (Cabozantinib)(au)

This is a literature review and update of the different therapeutic options approved and under study, of bone metastases due to castration resistant prostate cancer. It addresses general information of prostate cancer, the mechanisms by which it becomes resistant to castration, the appearance of bone metastases, treatment focused on antiresorptive therapy (bisphosphonates and RANK Ligand inhibitor), radiopharmaceuticals, radiotherapy and new drugs (Cabozantinib).(au)

Evaluation of mandibular morphometry in the bisphosphonate users / Evaluación de la morfometría mandibular en los usuarios de bifosfonatos

This study aimed to evaluate the effects of bisphosphonates on the mandibular bone. Bisphosphonates are drugs which are commonly used in the treatment of many diseases related to bone metabolism such as osteoporosis, breast cancer capable of bone metastasis, prostate and lung cancer and bone cancer such as multiple myeloma. Our study group consisted of a total of 100 panoramic radiographs which were obtained from the examinations of 50 individuals using bisphosphonate and 50 individuals in the control group who applied for routine dental examination to the Department of Oral and Maxillofacial Radiology of Akdeniz University Dentistry Faculty between years 2015 and 2016.The calculations of the mandibular cortical thickness (MCT), mandibular cortical index (MCI), panoramic mandibular index (PMI), condylar angle (CA), gonial angle (GA), antegonial angle (AGA), antegonial depth (AGD) and antegonial index (AGI) were made for each patient. It was found that both left and the right MCT and only the left PMI were affected by age. Only the left AGA and both the left and right MCT and AGD were affected by gender. The left and right AGI measurements of the patients using bisphosphonates were statistically lower than those of the individuals in the control group. Our results suggested that bisphosphonates had various effects on the jaw bones. However, further comprehensive studies need to be made to evaluate the longterm effect of bisphosphonates on bone metabolism.

Este estudio tuvo como objetivo evaluar los efectos de los bifosfonatos en el hueso mandibular. Los bifosfonatos son medicamentos que se usan comúnmente en el tratamiento de muchas enfermedades relacionadas con el metabolismo óseo, como la osteoporosis, el cáncer de mama, metástasis óseas, cáncer de próstata y pulmón y el cáncer de hueso como el mieloma múltiple. Nuestro grupo de estudio consistió en un total de 100 radiografías panorámicas que se obtuvieron de los exámenes de 50 individuos que utilizaron bisfosfonato y 50 individuos en el grupo de control que solicitaron un examen dental de rutina al Departamento de Radiología Oral y Maxilofacial de la Facultad de Odontología de la Universidad de Akdeniz, entre los años 2015 y 2016. En cada paciente se realizaron los cálculos del grosor cortical mandibular (GCM), índice cortical mandibular (ICM), índice mandibular panorámico (IMP), ángulo condilar (AC), ángulo gonial (AG), ángulo antegonial (AAG), profundidad antegonial ( PAG) y el índice antegonial (IAG). Se encontró que tanto el GCM izquierdo como el derecho y solo el IMP izquierdo estaban afectados por la edad. Solo el AAG izquierdo y el GCM izquierdo y derecho y el AGD fueron afectados de acuerdo al sexo. Las mediciones de IAG izquierdo y derecho de los pacientes que utilizan bifosfonatos fueron estadísticamente más bajas que las de los individuos en el grupo de control. Nuestros resultados sugirieron que los bifosfonatos tienen varios efectos en los huesos de la mandíbula. Sin embargo, es necesario realizar estudios más exhaustivos para evaluar el efecto a largo plazo de los bifosfonatos en el metabolismo óseo.

De la osteología a la osteomiología: tres décadas de aportes originales continuos al análisis biomecánico osteomuscular / From osteology to osteo-myology: three decades of continuous, original contributions to musculoskeletal biomechanical analysis

En consonancia con la orientación tradicional de nuestras investigaciones, la Osteología está incorporando progresivamente el análisis estructural-biomecánico óseo y las interacciones músculo-esqueléticas. En este artículo se sintetizan los aportes originales del CEMFoC a la Osteología moderna en el terreno biomecánico en forma didáctica, para que el lector aprecie sus posibles aplicaciones clínicas. Los hallazgos aportaron evidencias sucesivas en apoyo de dos proposiciones fundamentales: a) los huesos deben interpretarse como estructuras resistivas, biológicamente servocontroladas ("Los huesos tienden siempre a mantener un factor de seguridad que permite al cuerpo trabajar normalmente sin fracturarse" ­ Paradigma de Utah) y b) los huesos interactúan con su entorno mecánico, determinado principalmente por las contracciones musculares, en forma subordinada al entorno metabólico ("Los huesos son lo que los músculos quieren que sean, siempre que las hormonas lo permitan"). Los avances producidos se refieren, tanto cronológica como didácticamente, al conocimiento osteológico en general y al desarrollo de recursos novedosos para el diagnóstico no invasivo de fragilidad ósea, para distinguir entre osteopenias y osteoporosis, y para discriminar entre sus etiologías 'mecánica' y 'sistémica'. Finalmente, el nuevo conocimiento se integra en la proposición de un algoritmo diagnóstico para osteopenias y osteoporosis. El espíritu general de la presentación destaca que la evaluación osteomuscular dinámicamente integrada genera un nuevo espacio de análisis personalizado de los pacientes para la atención de cualquier osteopatía fragilizante con criterio biomecánico. (AU)

In consonance with the traditional spirit of our studies, skeletal research is being progressively focused on the structural-biomechanical analysis of bone and the muscle-bone interactions. In this article, the CEMFoC's members summarize their original findings in bone biomechanics and their potential clinical applications. These findings provided evidence supporting two fundamental hypotheses, namely, A. bones constitute resistive structures, which are biologically servo-controlled ('Bones tend to maintain a safety factor which allows the body to function normally avoiding fractures' ­ the 'Utah paradigm'), and B. the interactions of bones with their mechanical environment mainly are determined by the contraction of local muscles - 'bone-muscle units'), and are subordinated to the control of the metabolic environment ('Bones are what muscles wish them to be, provided that hormones allow for it'). The achievements in the field are presented in a chronological and didactical sequence concerning the general knowledge in Osteology and the development of novel resources for non-invasive diagnosis of bone fragility, aiming to distinguish between osteopenias and osteoporosis and the 'mechanical' and 'metabolic' etiology of these conditions. Finally, the integrated new knowledge is presented as supporting for a proposed diagnostic algorithm for osteopenias and osteoporosis. In general terms, the article highlights the dynamic evaluation of the musculoskeletal system as a whole, opening a new diagnostic field for a personalized evaluation of the patients affected by a boneweakening disease, based on functional and biomechanical criteria. (AU)

Statins and bonehealth: a mini review / Estatinas y salud ósea: una minirevisión

Statins are a widely prescribed class of medications that inhibit similar pathways as the anti-resorptive bisphosphonate drugs. Statins target the mevalonate pathway by blocking HMG-CoA reductase. Several recent meta-analyses concluded statins are osteoprotective in the general population. Here we present current literature exploring the mechanisms underlying the putative osteoprotective effects of statins. We also review recent clinical studies, ranging from observational cohort studies to randomized clinical trials, testing the effect of statins on bone health in various populations. (AU)

Las estatinas son un grupo de drogas prescriptas en forma habitual, con la capacidad de bloquear vías de señalización similares a las inhibidas por los amino-bisfosfonatos. Las estatinas inhiben la vía del mevalonato, a través del bloqueo de diferentes enzimas. Varios metaanálisis recientes llevaron a la conclusión de que las estatinas tienen capacidad osteoprotectora en la población general. En esta revisión presentamos la literatura actual describiendo los mecanismos que subyacen en el potencial efecto osteoprotector de las estatinas, como así también estudios observacionales y clínicos aleatorizados sobre el efecto de estatinas en la salud ósea en diversas poblaciones. (AU)

Hepatic Osteodystrophy: The Mechanism of Bone Loss in Hepatocellular Disease and the Effects of Pamidronate Treatment

OBJECTIVES: The present study was designed to evaluate the bone phenotypes and mechanisms involved in bone disorders associated with hepatic osteodystrophy. Hepatocellular disease was induced by carbon tetrachloride (CCl4). In addition, the effects of disodium pamidronate on bone tissue were evaluated. METHODS: The study included 4 groups of 15 mice: a) C = mice subjected to vehicle injections; b) C+P = mice subjected to vehicle and pamidronate injections; c) CCl4+V = mice subjected to CCl4 and vehicle injections; and d) CCl4+P = mice subjected to CCl4 and pamidronate injections. CCl4 or vehicle was administered for 8 weeks, while pamidronate or vehicle was injected at the end of the fourth week. Bone histomorphometry and biomechanical analysis were performed in tibiae, while femora were used for micro-computed tomography and gene expression. RESULTS: CCl4 mice exhibited decreased bone volume/trabecular volume and trabecular numbers, as well as increased trabecular separation, as determined by bone histomorphometry and micro-computed tomography, but these changes were not detected in the group treated with pamidronate. CCl4 mice showed increased numbers of osteoclasts and resorption surface. High serum levels of receptor activator of nuclear factor-κB ligand and the increased expression of tartrate-resistant acid phosphatase in the bones of CCl4 mice supported the enhancement of bone resorption in these mice. CONCLUSION: Taken together, these results suggest that bone resorption is the main mechanism of bone loss in chronic hepatocellular disease in mice.

Collagen sponge and rhBMP-2 improve socket healing in rats treated with zoledronic acid

Abstract The aim of the present study was to evaluate the possible use of a commercial absorbed collagen sponge and bone morphogenetic protein (BMP) for the prevention of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in rats. Twenty rats received intraperitoneal injections of 0.1-mg/kg of zoledronic acid three times a week for eight weeks before the extraction of both maxillary first molars after eight weeks. A collagen sponge (experimental group 1) and a collagen sponge with recombinant human BMP-2 (experimental group 2) were applied to the right extraction sockets of ten rats each. The 20 left extraction sockets (control groups 1 and 2) were left unprotected. After eight weeks, all rats were euthanized. Macroscopic analysis, micro-computed tomography (CT) analysis, and histological analysis were performed. There was a significant difference in the bone density between the control and experimental groups on micro-CT analysis. Impaired healing of the extraction sockets, indicating BRONJ, was observed in 80% of control group 1, 90% of control group 2, 30% of experimental group 1, and 20% of experimental group 2. The collagen sponge with/without BMP used for protecting the extraction socket had the potential for a positive effect in reducing the incidence of bisphosphonate-related osteonecrosis of the jaw in rats.

Estudio radiográfico de la asociación de antioxidantes y bifosfonatos en remodelación ósea peri-Implantaria / Radiographic antioxidants association and biphosphonates study in bone remodeling peri-implant

Estudios previos han demostrado que los bisfosfonatos son potentes inhibidores de la resorción ósea. El aceite de oliva (O) es rico en ácidos grasos monoinsaturados con potentes propiedades anti-oxidantes. El objetivo de este estudio fue estudiar el efecto del tratamiento de alendronato (AL) y pamidronato (PA) y de O sobre la regeneración tisular. Las fórmulas se dosificaron 0,5 mg/kg de peso para AL, y de 0,6 mg/kg de peso para PA. El O se administró en la dieta, 50 g/ Kg. Cincuenta y cuatro ratas macho de la línea Wistar se dividieron en 6 grupos. El grupo control (C), recibió semanalmente 0,3 ml/100g de peso corporal de solución salina vía subcutánea. El grupo (AL) recibió semanalmente por vía subcutánea en el miembro posterior izquierdo. El grupo (PA) se colocó igual que el grupo anterior. El grupo (O) fue tratado en la alimentación y en las áreas de la cirugía recibieron inyección subcutánea con solución fisiológica. El grupo (ALO) recibió tratamiento combinado con AL y O. El grupo (PAO) se trató igual al anterior. La cirugía consistió en una incisión longitudinal en las tibias realizando un defecto circular en la parte plana de cada tibia hasta llegar al hueso medular. Se tomaron radiografías a los 0, 7, 15, 30, 60 y 90 días y fueron analizadas con el Software Image Pro Plus. Los estudios estadísticos se realizaron a través del análisis de la variancia a dos y tres criterios de clasificación. Se evidencio un incremento en la densidad mineral ósea promedio (DMO) conforme avanza el tiempo en todos los grupos, siendo evidentes con PA a los 60 días. El tratamiento O mostró eficacia en la remodelación ósea, observándose un pico a los 60 días. Esto sugiere que O representa una opción terapéutica para el tratamiento de las patologías óseas.

Previous studies have shown that bisphosphonates are potent inhibitors of bone resorption. Olive oil (O) is rich in monounsaturated fatty acids with potent anti-oxidant properties. The objective of this work was to study the effect of alendronate treatment (AL) and pamidronate (PA) and O on tissue regeneration. Formulas 0.5 mg / kg for AL dosed, and 0.6 mg / kg for PA. O was administered in the diet, 50 g / kg. Fifty-four male rats Wistar were divided into 6 groups. The control group (C) received weekly 0.3 ml / 100g body weight of saline subcutaneously. The group (AL) received a weekly dose subcutaneously in the left posterior limb. The group (PA) was placed as the previous group. The group (O) was treated in food and in the areas of surgery received subcutaneousinjection with saline. The group (ALO) received combined treatment with Al and O. The group (PAO) was treated the same as before. Surgery consisted of a longitudinal incision in the warm using a circular on the flat side of each tibia until the medullary bone defect. X-rays at 0, 7, 15, 30, 60 and 90 days were taken and analyzed with Image Pro Plus Software. Statistical studies were conducted through analysis of variance to two and three classification criteria. Results: an increase in the average bone mineral density (BMD) was evident as time progresses in all groups, with PA still evident at 60 days. Or treatment showed efficacy in bone remodeling observed a peak at 60 days. Conclusions: This suggests that O represents a therapeutic option for the treatment of bone disease.

Effects of Zoledronic Acid on Orthodontic Tooth Movement in Rats

Abstract The purpose of this study was to assess the effects of the administration of zoledronic acid (ZA) during orthodontic movement in rats. A hundred and twenty male Wistar rats were applied force of 30 cN with spring closed nickel-titanium to move the upper right first molar to mesial. In the Control Movement group (CM), only tooth movement was performed; the Control Acid Zoledronic group (CAZ) received a single dose (0.1 mg/kg) of ZA; the Experimental Acid Zoledronic group (EAZ) received a single dose (0.1 mg/kg) one week prior to the start of tooth movement; and the Control Without movement group (CWM) that received no drug and without application of tooth movement. The animals were euthanized after 3, 7 and 14 days. Tooth movement was measured using a caliper, the number of osteoclasts using TRAP staining, the expression of mature and immature collagen using picrosirius staining, and the presence of hyaline areas and root resorption using HE. The data were compared using two-way ANOVA, Tukey HSD, Games-Howell and chi-squared test, at the 5% significance level. It was observed a smaller number of osteoclasts and greater percentage of hyaline area in the EAZ group. There was no difference among the groups regarding bone remodeling, root resorption and tooth movement for all observed times.

Resumo A proposta deste estudo foi avaliar os efeitos da administração do ácido zoledrônico (ZA) durante a movimentação ortodôntica em ratos. Cento e vinte ratos Wistar, machos, foram submetidos a aplicação de uma força de 30 cN através de uma mola fechada de níquel-titânio para mover o primeiro molar superior direito para mesial. No grupo Controle Movimentação (CM), apenas a movimentação dentária foi realizada; o grupo Controle Ácido Zoledrônico (CAZ) recebeu uma única dose (0,1 mg/kg) de ZA; o grupo Experimental Ácido Zoledrônico (EAZ) recebeu uma única dose (0,1 mg/Kg) uma semana antes do início da movimentação dentária; e o grupo Controle Sem Movimentação (CWM) não receberam nenhum tipo de droga e não foi realizado movimentação dentária. Os animais foram eutanásiados após 3, 7 e 14 dias. A movimentação dentária foi mensurada através de um paquímetro, o número de osteoclastos utilizando coloração TRAP, a expressão do colágeno maturo e imaturo através da coloração Picrosírius, e a presença de áreas hialinas e reabsorção radicular utilizando HE. Os dados foram comparados utilizando ANOVA a dois critérios, Tukey HSD, Games-Howell e teste de qui-quadrado, ao nível de significância de 5%. Verificou-se menor número de osteoclastos e maior porcentagem de área hialina no grupo EAZ. Não houve diferença entre grupos quanto à neoformação óssea, reabsorção radicular e movimentação dentária em todos os tempos observados.

Using agents that suppress bone remodeling to treat or prevent joint disease: quo vadis?

Treatment of osteoarthritis (OA) with antiremodeling agents has had a mixed record of results. It is likely that remodeling suppression is only effective when used in the early phases of OA, before significant progression. Animal and human studies largely bear this out. Treatment of young mice with a RANKL inhibitor suppresses bone resorption and prevents OA progression. Likewise, bisphosphonate treatments in rodents and rabbits with induced injury or inflammatory arthritis, reduced cartilage degeneration when administered preemptively, but later administration did not. The increased prevalence of OA in women after the menopause, and presence of estrogen receptors in joint tissues, suggests that treatment with estrogens or Selective Estrogen Receptor Modulators may be effective. However, in clinical trials of knee and hip, results show decreased or increased risk for OA, or no effect. Raloxifene had positive effects in animal models, but no effect in human studies. More recent potential treatments such as strontium ranelate or cathepsin-K inhibitors may be effective, but may work directly on the cartilage rather than through their well-known effects on bone. The conclusion from these studies is that anti-remodeling agents must be administered pre-emptively or in the very early stages of disease to be effective. This means that better imaging techniques or identification of early structural changes in bone that occur before progressive cartilage destruction must be developed. (AU)

ß-ARRESTIN/CONNEXIN 43 (Cx43) complex anchors ERKS outside the nucleus: a prerequisite for bisphosphonate antiapoptotic effect mediated by Cx43/ERK in osteocytes / El complejo ß-ARRESTINA/CONEXINA 43 (Cx43) retiene ERKS fuera del núcleo: un paso necesario para el efecto anti-apoptótico de los bisfosfonatos mediado por Cx34/ERK en osteocitos

Bisphosphonates (BPs) anti-fracture efficacy may be due in part to inhibition of osteocyte apoptosis. This effect requires opening of connexin (Cx) 43 hemichannels and phosphorylation of the extracellular signal regulated kinases (ERKs). However, unlike ERK activation by other stimuli, the Cx43/ERK pathway activated by BPs does not result in nuclear ERK accumulation. Instead, the anti-apoptotic effect of BPs depends on phosphorylation of cytoplasmic ERK targets and is abolished by forced nuclear retention of ERKs. We now report that ERKs and the scaffolding protein ß-arrestin co-immuno-precipitate with Cx43 in MLO-Y4 osteocytic cells and that the BP alendronate increases this association. Moreover, ERK2 fused to red fluorescent protein (ERK2-RFP) co-localizes with Cx43 fused to green fluorescent protein outside the nucleus in cells untreated or treated with alendronate. Alendronate does not induce ERK nuclear accumulation in cells transfected with wild type ß-arrestin (wtARR) or vector control, whereas it does in cells expressing a dominant negative ß-arrestin mutant (dnARR) consisting of the ß-arrestin-clathrin binding domain that competes with endogenous ß-arrestin for binding to clathrin. Alendronate activates ERKs in dnARRtransfected cells as effectively as in cells transfected with wtARR, demonstrating that dnARR only interferes with subcellular localization but not with activation of ERKs by BPs. Further, whereas alendronate inhibits apoptosis in cells expressing wtARR or vector control, it is ineffective in cells expressing dnARR. Thus, BPs induce the formation of a complex comprising Cx43, ß-arrestin, and clathrin, which directs ERKs outside the nucleus and is indispensable for osteocyte survival induced by BPs. (AU)

La efectividad de los bisfosfonatos (BPs) en la prevención de fracturas puede deberse en parte a la inhibición de la apoptosis de osteocitos. Este efecto depende de la apertura de hemicanales de conexina (Cx) 43 y la fosforilación de quinasas reguladas por señales extracelulares (ERKs). Sin embargo, a diferencia de la activación de ERKs debida a otros estímulos, la vía de señalización Cx43/ERK activada por BPs no conlleva la acumulación de ERKs en el núcleo. El efecto anti-apoptótico de los BPs depende de la fosforilación de blancos citoplasmáticos de ERKs y es inhibido cuando las quinasas son retenidas en el núcleo. En este estudio hemos demostrado que ERKs y la proteína "scaffolding" ß-arrestina co-inmunoprecipitan con Cx43 en células osteocíticas MLO-Y4 y que alendronato aumenta esta asociación. Más aún, ERK2 fusionada a la proteína roja fluorescente (ERK2-RFP) co-localiza con Cx43 fusionada con la proteína verde fluorescente fuera del núcleo en células tratadas con vehículo o alendronato. Alendronato no indujo la acumulación nuclear de ERK en células transfectadas con ß-arrestina nativa (wtARR) o con un vector control, pero si lo hizo en células que expresan una forma dominante negativa de ß-arrestina (dnARR), consistente en el dominio de interacción entre ß-arrestina y clatrina, y que compite con ß-arrestina endógena por la unión a clatrina. Alendronato activa ERKs con la misma eficiencia en células transfectadas con dnARR o wtARR, demostrando que dnARR sólo interfiere con la localización subcelular de ERKs, pero no con su activación inducida por los BPs. Más aún, mientras alendronato inhibe apoptosis en células que expresan wtARR o vector control, es inefectivo en células que expresan dnARR. En conclusión, los BPs inducen la formación de un complejo que incluye Cx43, ß-arrestina y clatrina, el cual retiene ERKs fuera del núcleo y es indispensable para la sobrevida de los osteocitos inducida por estas drogas. (AU)

Response of a co-culture model of epithelial cells and gingival fibroblasts to zoledronic acid

Abstract Osteonecrosis of the jaw is an adverse effect of bisphosphonates. While the etiopathogenesis of this condition has been investigated, the interactions and effects of bisphosphonates on oral mucosa cells remain unclear. It is hypothesized that cell culture models, such as co-culture or three-dimensional cell culture models, can provide valuable insight. Therefore, the aim of this study was to evaluate the effects of zoledronic acid (ZA) on epithelial cells and gingival fibroblasts in a co-culture model. Briefly, epithelial cells were seeded on transwell inserts and gingival fibroblasts were seeded in the lower well of 24-well plates. The latter were treated with ZA (5 μM) for 24 or 48 h. Cell viability and synthesis of the inflammatory chemokine, CCL2, were subsequently assessed. Data were subjected to statistical analysis with a 5% significance level. In the presence of ZA, the epithelial cells exhibited significant toxicity in both cell culture models and at both time points. However, greater cytotoxicity was observed in the co-culture model. Greater viability for the gingival fibroblasts was also associated with the co-culture model, and ZA-mediated toxicity was observed for the 48 h time point. ZA promoted a significant increase in CCL2 synthesis in both sets of cells, with greater CCL2 synthesis detected in the gingival fibroblasts. However, this effect was diminished in the co-culture model. Taken together, these results confirm the specific response patterns of the cells seeded in the co-culture model and also demonstrate the protective mechanism that is mediated by epithelial/mesenchymal cell interactions upon exposure to ZA.

Changes in cortical bone channels network and osteocyte organization after the use of zoledronic acid

Objective The aim of this study was to evaluate the effects of zoledronic acid (ZA) on the cortical bone channels network (CBCN) and osteocyte organization in relation to the bone channels. Materials and methods Eighteen male Wistar rats were divided into control (CG) and test groups (TG). Twelve animals from TG received 3 ZA doses (7.5 µg/kg), and 6 animals from CG did not receive any medication. TG animals were euthanized at 14 (n = 6) and 75 (n = 6) dadys after drug injection. CBCN was analyzed in mandibles and tibias using computational routines. The osteocyte organization was qualitatively evaluated in tibias using a three-dimensional reconstruction of images from serial histological sections. Results Significant differences in CBCN of tibia were found between the treated and untreated rats, with a wider range of sizes and shapes of the channels after the use of ZA (channels area p = 0.0063, channels area SD p = 0.0276) and less bone matrix (bone volume p = 0.0388). The alterations in the channels’ morphology were more evident at 75 days after the drug injection (channels perimeter p = 0.0286). No differences were found in mandibles CBCN. The osteocyte distribution revealed more variable patterns of cell distribution in ZA groups, with non-homogeneous distribution of cells in relation to the bone channels. Conclusion Zoledronic acid induces structural changes in CBCN and modifies the osteocyte arrangement in cortical bone in the tibia; also, the variability in the morphology of bone channels became more evident after a certain time of the use of the drug.

Experimental evidence of pharmacological management of anchorage in Orthodontics: A systematic review

Introduction: Orthodontic anchorage is one of the most challenging aspects of Orthodontics. Preventing undesired movement of teeth could result in safer and less complicated orthodontic treatment. Recently, several reviews have been published about the effects of different molecules on bone physiology and the clinical side effects in Orthodontics. However, the effects of local application of these substances on the rate of orthodontic tooth movement have not been assessed.Objectives: The aim of this research was to analyze the scientific evidence published in the literature about the effects of different molecules on orthodontic anchorage.Methods: The literature was systematically reviewed using PubMed/Medline, Scopus and Cochrane databases from 2000 up to July 31st, 2014. Articles were independently selected by two different researchers based on previously established inclusion and exclusion criteria, with a concordance Kappa index of 0.86. The methodological quality of the reviewed papers was performed.Results: Search strategy identified 270 articles. Twenty-five of them were selected after application of inclusion/exclusion criteria, and only 11 qualified for final analysis. Molecules involved in orthodontic anchorage were divided into three main groups: osteoprotegerin (OPG), bisphosphonates (BPs) and other molecules (OMs).Conclusions: Different drugs are able to alter the bone remodeling cycle, influencing osteoclast function and, therefore, tooth movement. Thus, they could be used in order to provide maximal anchorage while preventing undesired movements. OPG was found the most effective molecule in blocking the action of osteoclasts, thereby reducing undesired movements.

Introdução: a ancoragem ortodôntica é um dos aspectos mais desafiadores da Ortodontia. A prevenção de movimentos dentários indesejados poderia resultar em um tratamento ortodôntico mais seguro e menos complexo. Recentemente, foram publicadas várias revisões de literatura sobre os efeitos de diferentes substâncias na fisiologia do tecido ósseo e os efeitos colaterais clínicos na Ortodontia. Porém, os efeitos da aplicação local dessas substâncias no grau de movimentação dentária ortodôntica não foram avaliados.Objetivos: o objetivo da presente pesquisa foi analisar a evidência científica publicada na literatura sobre os efeitos de diferentes substâncias na ancoragem ortodôntica.Métodos: a literatura foi sistematicamente revisada utilizando-se as bases de dados PubMed/Medline, Scopus e Cochrane, de 2000 a 31 de julho de 2014. Os artigos foram selecionados, de maneira independente, por dois pesquisadores diferentes, tendo como base critérios de inclusão e exclusão previamente estabelecidos, com um índice Kappa de concordância de 0,86. A qualidade metodológica dos artigos revisados foi analisada.Resultados: a estratégia de pesquisa identificou 270 artigos; 25 artigos foram selecionados após a aplicação dos critérios de inclusão e exclusão, mas apenas 11 foram qualificados para a análise final. As substâncias envolvidas na ancoragem ortodôntica foram divididas em três grupos principais: osteoprotegerina (OPG), bisfosfonatos (BFs) e outras substâncias (OSs).Conclusões: diferentes substâncias são capazes de alterar o ciclo de remodelação óssea, influenciando na função dos osteoclastos e, portanto, na movimentação dentária. Sendo assim, essas substâncias podem ser utilizadas para promover o máximo de ancoragem e prevenir movimentos indesejados. A OPG foi a substância mais eficaz no bloqueio da ação dos osteoclastos, reduzindo os movimentos indesejados.

Evaluación del manejo farmacológico de la osteoporosis y la osteopenia en una institución de régimen especial de Bogotá / Pharmacological evaluation of osteoporosis and osteopenia treatment in an institution under the special health system in Bogotá

Objetivo Evaluar los hábitos de prescripción de medicamentos utilizados en el tratamiento de osteoporosis y osteopenia en una institución de salud de régimen especial de Bogotá, comparados guías de manejo internacional de la osteoporosis. Metodología Se realizó un estudio observacional descriptivo de corte transversal con recolección retrospectiva de la información. Corresponde a un estudio de utilización de medicamentos sobre hábitos de prescripción, para el cual se tomó la información de 332 pacientes tratados con Bifosfonatos, sales de calcio, Ranelato de Estroncio y Teriparatida. Se evaluaron los hábitos de prescripción mediante la comparación con las Guías de manejo de la National Osteoporosis Foundation (NOF) y el National Institute for Health and Clinical Excellence (NICE). Resultados El 89 % de la población corresponde a mujeres con un promedio de edad de 67 años. La dosis y frecuencia de administración corresponde a lo establecido por las guías de manejo; el 32,2 % fue tratado con Bisfosfonatos por más de 3 años, el 94,2 % fue tratado en prevención primaria y el 89,6 % fue tratado sin diagnóstico de Osteoporosis mediante Densitometría Mineral Ósea (DMO). De acuerdo a las recomendaciones de la guía NOF el 67,3 % de los pacientes se trató innecesariamente. Conclusiones Los hábitos de prescripción de medicamentos utilizados en el tratamiento de las osteoporosis no están de acuerdo a las guías de manejo, evidenciándose un uso no adecuado especialmente de bifosfonatos.

Objetive To evaluate habits related to the prescription of drugs used in the treatment of osteoporosis and osteopenia in a health institution in Bogota as compared to two international clinical practice guidelines. Methodology An observation and cross-sectional study with retrospective data collection. It is a study of drug-prescribing habits. Information was taken from 331 patients treated with bisphosphonates, calcium salts, strontium ranelate and teriparatide. The prescription habits were assessed by way of a comparison with the NOF clinician's guide for the prevention and treatment of osteoporosis and the National Institute for Health and Clinical Excellence (NICE) guidelines. Results 89 % of the population were women with an average age of 67 years. The dose and frequency of the administration of drugs was in accordance with established guidelines. 32.2 % of patients were treated with bisphosphonates for over 3 years, 94.2% were treated with primary prevention, and 89.6 % had been treated without any osteoporosis diagnosis by DMO. Compared to the NOF guide, 67.3 % of the patients were treated unnecessarily. Conclusions The drug prescription habits used in the treatment of the osteoporosis do not follow the guidelines, showing non-adequate use, especially of bisphosphonates.

Efeito combinado do ácido zoledrônico e do alfacalcidol no tratamento da osteoporose por desuso em ratos / Additive effect of zoledronic acid and alfacalcidol in the treatment of disuse osteoporosis in rats

Objetivos: O desuso pelo repouso no leito, pela imobilização de membros ou por missões espaciais provoca a perda óssea rápida. Fez-se este estudo para investigar os efeitos terapêuticos do ácido zoledrônico (ZOL), isoladamente e em combinação ao alfacalcidol (ALF), em um modelo de rato com osteoporose por desuso. Métodos: Ratos Wistar machos de três meses foram submetidos à imobilização da pata traseira direita (IPTD) por 10 semanas para induzir a osteopenia; em seguida, foram divididos em quatro grupos: 1 – IPTD para controle positivo; 2 – IPTD mais ZOL (50 µg/kg, dose única intravenosa); 3 – IPTD mais ALF (0,5 µg/kg, via oral diariamente); 4 – IPTD mais ALF (0,5 µg/kg, via oral diariamente) mais ZOL (50 µg/kg, dose única intravenosa) por outras 10 semanas. Um grupo de ratos não imobilizados foi usado como controle negativo. No fim do tratamento, os fêmures foram removidos e testaram-se a porosidade do osso e suas propriedades mecânicas, além do peso seco e das cinzas do osso. Resultados: A terapia combinada com ZOL mais ALF foi mais eficaz em reduzir a porosidade do osso do que a monoterapia com um dos fármacos administrado isoladamente em ratos submetidos à IPTD. No que diz respeito à melhoria da resistência mecânica da diáfise femoral média, o tratamento combinado com ZOL mais ALF foi mais eficaz do que a monoterapia com um dos fármacos administrado isoladamente. Além disso, a terapia combinada com ZOL mais ALF foi mais eficaz na melhoria do peso seco e das cinzas do osso do que a monoterapia com ZOL ou ALF em ratos submetidos à IPTD. Conclusões: Esses dados sugerem que a terapia combinada com ZOL mais ALF representa uma opção terapêutica potencialmente útil para o tratamento da osteoporose por desuso. .

Objectives: Disuse by bed rest, limb immobilization or space flight causes rapid bone loss. We conducted the present study to investigate the therapeutic effects of zoledronic acid (ZOL), alone and in combination with alfacalcidol (ALF) in a rat model of disuse osteoporosis. Methods: In the present study, 3-month-old male Wistar rats had their right hind-limb immobilized (RHLI) for 10 weeks to induce osteopenia, then were divided into four groups: 1 – RHLI positive control; 2 – RHLI plus ZOL (50 µg/kg, i.v. single dose); 3 – RHLI plus ALF (0.5 µg/kg, oral gauge daily); 4 – RHLI plus ALF (0.5 µg/kg, oral gauge daily) plus ZOL (50 µg/kg, i.v. single dose) for another 10 weeks. One group of non-immobilized rats was used as negative control. At the end of the treatment, the femurs were removed and tested for bone porosity, bone mechanical properties, and bone dry and ash weight. Results: Combination therapy with ZOL plus ALF was more effective in decreasing bone porosity than each drug administered as monotherapy in RHLI rats. With respect to improvement in the mechanical strength of the femoral mid-shaft, the combination treatment of ZOL plus ALF was more effective than each drug administered as a monotherapy. Moreover, combination therapy using ZOL plus ALF was more effective in improving dry bone and ash weight, than single-drug therapy using ZOL or ALF in RHLI rats. Conclusions: These data suggest that combination therapy with ZOL plus ALF represents a potentially useful therapeutic option for the treatment of disuse osteoporosis. .

Efeitos combinados do ácido zoledrônico e do propranolol sobre a densidade óssea e marcadores bioquímicos de remodelação óssea em ratas osteopênicas submetidas à ovariectomia / Additive effects of zoledronic acid and propranolol on bone density and biochemical markers of bone turnover in osteopenic ovariectomized rats

Objetivos: Este estudo foi desenvolvido para investigar a eficácia e a segurança do ácidozoledrônico (ZOL) e do propranolol (PRO) como monoterapia e terapia combinada em ummodelo de rato com osteoporose pós-menopáusica. Métodos: Ratas Wistar fêmeas foram ovariectomizadas (OVX) ou submetidas à cirurgia simulada (placebo) aos três meses de idade. Doze semanas depois da cirurgia, as ratas foram divididas em seis grupos: (1) placebo + veículo; (2) OVX + veículo; (3) OVX + ZOL (100 µg/kg, dose única intravenosa); (4) OVX + ZOL (50 µg/kg, dose única intravenosa); (5) OVX + PRO (0,1 mg/kg, via subcutânea, cinco dias por semana); (6) OVX + ZOL (50 µg/kg, dose única intravenosa) + PRO (0,1 mg/kg, via subcutânea, cinco dias por semana) durante 12 semanas. Depois do tratamento, testou-se a densidade óssea, a porosidade e a microarquitetura tra-becular dos fêmures. Também foram avaliados marcadores bioquímicos séricos e urinários. Resultados: A terapia combinada com ZOL mais PRO foi mais eficaz em corrigir a diminuição do cálcio sérico e o aumento do nível sérico de fosfatase alcalina e fosfatase ácida resistenteao tartarato do que a monoterapia com ZOL ou PRO. Além disso, a terapia combinada comZOL mais PRO foi mais eficaz em corrigir o aumento dos níveis urinários de cálcio, fósforo ecreatinina do que a monoterapia com ZOL ou PRO. A terapia combinada com ZOL mais PRO também preservou a microarquitetura trabecular e a porosidade do osso cortical. Conclusão: Os resultados sugerem que a terapia combinada com ZOL mais PRO pode ser aabordagem mais eficaz para o tratamento da osteoporose grave em humanos. .

Objectives: The present study was designed to investigate further the efficacy and safety of zoledronic acid (ZOL) and propranolol (PRO) as monotherapy and combination therapy in a rat model of postmenopausal osteoporosis. Methods: Female Wistar rats were ovariectomized (OVX) or sham-operated at 3 months ofage. Twelve weeks post-surgery, rats were randomized into six groups: (1) sham + vehicle; (2) OVX + vehicle; (3) OVX + ZOL (100 뀅g/kg, i.v. single dose); (4) OVX + ZOL (50 뀅g/kg, i.v. single dose); (5) OVX + PRO (0.1 mg/kg, s.c. 5 days per week); (6) OVX + ZOL (50 뀅g/kg, i.v. single dose) + PRO (0.1 mg/kg, s.c. 5 days per week) for 12 weeks. After treatment, femurs were tested for bone density, porosity and trabecular micro-architecture. Biochemical markers in serum and urine were also determined. Results: Combined treatment with ZOL plus PRO corrected the decrease in serum calcium and increase in serum alkaline phosphatase and tartarate resistant acid phosphatase level better than single-drug therapy using ZOL or PRO. Moreover, combined treatment with ZOL plus PRO corrected the increase in urine calcium, phosphorous and creatinine level better than single-drug therapy using ZOL or PRO. Combination therapy using ZOL plus PRO also preserved the trabecular micro-architecture and cortical bone porosity. Conclusion: These data suggest that combined treatment with ZOL plus PRO could be a more effective approach for treating severe osteoporosis in humans. .

Comparative Effects of Ibandronate and Paclitaxel on Immunocompetent Bone Metastasis Model

PURPOSE: Bone metastasis invariably increases morbidity and mortality. This study compares the effects of ibandronate and paclitaxel on bone structure and its mechanical properties and biochemical turnover in resorption markers using an immunocompetent Walker 256-Sprague-Dawley model, which was subjected to tumor-induced osteolysis. MATERIALS AND METHODS: Seventy rats were divided equally into 4 groups: 1) sham group (SHAM), 2) tumor group (CANC), 3) ibandronate treated group (IBAN), and 4) paclitaxel treated group (PAC). Morphological indices [bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp)] and mechanical properties (failure load, stiffness) were evaluated after thirty days of treatment period. Bone resorption rate was analysed using serum deoxypyridinoline (Dpd) concentrations. RESULTS: Morphological indices showed that ibandronate (anti-resorptive drug) had a better effect in treating tumor-induced architectural changes in bone than paclitaxel (chemotherapeutic drug). The deterioration in bone architecture was reflected in the biomechanical properties of bone as studied with decreased failure load (F(x)) and stiffness (S) of the bone on the 30th day postsurgery. Dpd concentrations were significantly lower in the IBAN group, indicating successful inhibition of bone resorption and destruction. CONCLUSION: Ibandronate was found to be as effective as higher doses of paclitaxel in maintaining stiffness of bone. Paclitaxel treatment did not appear to inhibit osteoclast resorption, which is contrary to earlier in-vitro literature. Emphasis should be placed on the use of immunocompetent models for examining drug efficacy since it adequately reflects bone metastasis in clinical scenarios.

Fraturas femorais atípicas por uso prolongado de bifosfonatos: mitos e verdades / Atypical femoral fractures by prolonged use of bisphosphonates: myths and truths

As fraturas atípicas do fêmur são raras, mas sua crescente descrição na literatura e sua provável associação com os bifosfonatos trouxeram à tona uma série de aspectos ainda nebulosos no tocante ao uso contínuo dessas drogas. O protocolo mais sugerido atualmente, embora ainda não totalmente estabelecido, orienta a retirada da medicação após três a cinco anos de uso contínuo dos bifosfonatos, retornando cerca de três anos depois, quando houver necessidade

Atypical femur fractures are rare but a growing concern, as they are more common in patients who use long-term bisphosphonates. This brought to light a number of issues still unknown regarding the continued use of these drugs. Nowadays the most suggested protocol, although not yet fully esbablished, considers not more than three to five years of bisphosphonate treatment for osteoporotic patients, returning about three years later, when the need arises

Efeito do alendronato de sódio em molares de rato em formação após luxação lateral / Effect of sodium alendronate on developing molars of young rats after lateral luxation

Os bisfosfonatos são drogas capazes de inibir a reabsorção óssea por meio de seu efeito direto sobre as células ósseas, interferindo na dinâmica dos tecidos mineralizados. O alendronato (ALN), um tipo de bisfosfonato nitrogenado, foi utilizado com o objetivo de investigar os seus efeitos sobre os tecidos dentários e periodontais após luxação lateral de molares com as raízes em desenvolvimento. Ratos Wistar com 21 dias de idade tiveram os segundos molares superiores luxados lateralmente. Doses diárias de 2,5 mg / kg de ALN começaram no dia seguinte à luxação; os controles receberam solução salina estéril. As maxilas foram fixadas, descalcificadas e incluídas em parafina ou em resina Spurr 7, 14 e 21 dias pós-luxação. Os cortes foram corados com H & E, incubados por histoquímica TRAP e imuno marcados para osteopontina (OPN), bem como para análise ultraestrutural. Após 21 dias, o ápice dos molares luxados sem ALN estava aberto e desorganizado, coberto por uma camada irregular de cemento celular. Os molares luxados dos animais tratados com ALN apresentaram alguns locais de anquilose, bem como lacunas de reabsorção na superfície do cemento. Os osteoclastos TRAP positivos foram mais numerosos no grupo ALN, apesar de sua aparência latente e sua localização, afastados das trabéculas ósseas, em relação aos controles, achado que foi confirmado com a análise ultraestrutural. A imunomarcação de OPN revelou uma linha grossa imunopositiva na dentina, que deve ter surgido a partir do momento da luxação, enquanto que as amostras tratadas com ALN não apresentaram alterações na dentina. Os resultados indicam que o alendronato inibe algumas alterações na dentina e na formação do cemento, induzidas pelo trauma dental de luxação.

Bisphosphonates are drugs that inhibit bone resorption through its direct effect on bone cells, interfering with the dynamics of mineralized tissues. Alendronate (ALN), a nitrogenated bisphosphonate, was used in order to investigate their effects on dental and periodontal tissues after lateral dislocation of molars with developing roots. Twenty one days old Wistar rats had their second molars laterally l. Daily doses of 2.5 mg / kg ALN started the day following the dislocation, while controls received saline solution. The maxillae were fixed, decalcified and embedded in paraffin or in Spurr resin after 7, 14 and 21 days post-dislocation. The sections were stained with H & E, incubated for TRAP, immunolabeled for osteopontin (OPN), and ultrastructurally analyzed by transmission electron microscopy. After 21 days, the apex of the luxated molar without ALN was open and disorganized, covered by an irregular layer of cellular cementum. The luxated molar from ALN-treated animals showed some areas of ankylosis and resorption lacunae on the cementum surface. TRAP-positive osteoclasts were more numerous in the ALN group, despite their latent appearance compared to controls, a finding that was ultrastructurally confirmed. OPN immunostaining revealed a thick immunopositive line in dentin, which must be resultant from the moment of dislocation, while the samples treated with ALN showed no changes in dentin. The results indicate that alendronate inhibits some changes in dentin and cementum formation induced by dental trauma of lateral luxation.