Production of bone mineral material and BMP-2 in osteoblasts cultured on double acid-etched titanium

Background: The study of osteoblasts and their osteogenic functions is essential in order to understand them and their applications in implantology. In this sense, this study try to study BMP-2 production and bone matrix deposition, in addition to other biological variables, in osteoblasts cultured on a rough double acid-etched titanium surface (Osseotite®, Biomet 3i, Palm Beach Garden, Florida, USA) in comparison to a smooth titanium surface (machined) and a control Petri dish. Material and Methods: An in vitro prospective study. NHOst human osteoblasts from the femur were cultured on three different surfaces: Control group: 25-mm methacrylate dish (n = 6); Machined group: titanium discs with machined surface (n = 6) and Experimental group: titanium discs with a double acid-etched nitric and hydrofluoric Osseotite® acid surface (n = 6). A quantification of the mitochondrial membrane potential, and studies of apoptosis, mobility and adhesion, bone productivity (BMP-2) and cellular bone synthesis were carried out after culturing the three groups for forty-eight hours. Results: A statistically significant difference was observed in the production of BMP-2 between the experimental group and the other two groups (22.33% ± 11.06 vs. 13.10% ± 5.51 in the machined group and 3.88% ± 3.43 in the control group). Differences in cellular bone synthesis were also observed between the groups (28.34% ± 14.4% in the experimental group vs. 20.03% ± 6.79 in the machined group and 19.34% ± 15.93% in the control group). Conclusions: In comparison with machined surfaces, Osseotite® surfaces favor BMP-2 production and bone synthesis as a result of the osteoblasts in contact with it (AU)

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Presence of matrix vesicles in the body of odontoblasts and in the inner thirdof dentinal tissue: A scanning electron microscopyc study

Objectives: The aim of this report is to present the results of a scanning electron microscopic study on the presence of matrix vesicles (MVs) found in human dentine. Study Design: Dentin tissue from 20 human bicuspids was analyzed by means of scanning electron microscopy. Results: MVs were found as outgrowths of the cellular membrane of the odontoblastic body, the more proximal portion of the odontoblastic process before entering the dentinal tubule and in the odontoblastic process within the inner third of the dentin. Size of MVs varied depending on location. In the inner third of dentin, they were seen indiverse positions; as membranal outgrowths, deriving from the odontoblastic process, lying free in the intratubular space and attached to the dentinal wall. Sometimes, they were seen organized forming groups of different size sand shapes or as multivesicular chains running from the surface of the odontoblastic process to the tubular wall. MVs were present in places never considered: 1) the body of odontoblasts; 2) the most proximal part of the odontoblastic processes before entering the circumpulpal dentine and also: 3) in the inner third of dentinal tissue. Conclusions: According to our results, MVs not only participate during mantle dentin mineralization during early dentinogenesis, they also contribute during the mineralization process of the inner dentin (AU)

A comparative study of platelet-rich plasma, hydroxyapatite, demineralizedbone matrix and autologous bone to promote bone regeneration after mandibularimpacted third molar extraction

Objectives: 1) to compare mandibular bone regeneration by applying autologous bone, platelet-rich plasma andtwo biomaterials (synthetic calcium hydroxyapatite, and demineralized bone matrix), and thus establish the potentialbenefits of these biomaterials in the regeneration of postextraction alveolar bone, 2) to identify wich of themaccelerates more bone regeneration and 3) to determine whether there are differences in the postoperative period(pain, swelling, trismus, infection) depending on the material used.Study Design: It consists in a prospective, controlled (with a split- mouth design) and double blinded study. We useas a model an easily reproducible non-critical bone defect: the defect that remains after extraction of mandibularimpacted third molar. The study design is based on the extraction of two mandibular impacted third molars ina patient during the same surgical procedure by the same surgeon. We assessed postoperative clinical data, andshort, medium and long term neoformation of alveolar bone after extraction. We compared the two sockets (rightand left), which had been grafted in a different way with the various elements mentioned above. In addition, wecompared the postoperative inflammatory symptoms between groups.Results: The highest acceleration in bone formation was observed in groups in which we used autologous boneand demineralized bone matrix. There were no statistically significant differences between groups regarding pain,swelling, trismus and infection throughout the postoperative period.Conclusions: According to the results of our study, autologous bone persists as the gold standard material for boneregeneration. Among the assessed biomaterials, demineralized bone matrix has yielded the best results obtained.No significant differences in the postoperative (pain, swelling, trismus and infectious events) were observed, dependingon the type of material used as a graft (AU)

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Estudio comparativo del uso de la matriz ósea desmineralizada de origen humana y de la poliuretana derivada del aceite de mamona sobre el proceso de regeneración ósea. Estudio histométrico en calota de conejos / A comparative study on the use of demineralized bone matrix of human origin and polyurethane derived from castor oil in bone regeneration processes. A histometric study on rabbit calvaria

Objetivo. Analizar histométricamente el efecto de la matriz óseadesmineralizada de origen humana y de la resina poliuretana derivada delaceite de mamona, sobre el proceso de regeneración ósea. Diseño del estudio:fueron utilizados 24 conejos y en cada calota craniana fueron preparadasdos cavidades quirúrgicas, siendo una a cada lado de la sutura parietal.Los animales fueron divididos en dos grupos. En el grupo I la cavidadexperimental (lado derecho) fue rellenada con la poliuretana derivadadel aceite de mamona, mientras que en el grupo II la cavidad experimentalfue rellenada con la matriz ósea desmineralizada de origen humano. Lascavidades de control fueron rellenadas solo con la sangre del animal. Losanimales fueron sacrificados en los períodos postoperatorios de 04, 07 y15 semanas. Resultados. El análisis estadístico, realizado en base de losdatos de la histometría, mostró una mayor neoformación ósea de los gruposI y II en relación al grupo control, no existiendo diferencia estadísticacuando los grupos experimentales fueron comparados. Conclusiones. Eluso de poliuretana derivada del aceite de mamona y matriz ósea desmineralizadade origen humano mejoran el proceso de regeneración cuandolo comparamos a la regeneración ósea normal resultando que entre ambosmateriales tuvieron un comportamiento similar sin diferencias estadísticas significantes entre sí (AU)

Objective. The present study was aimed at carrying out a histological and histometric analysis on the effect of humande mineralized bone matrix and a polyurethane resin, derived of the castor bean oil, on the bone regeneration process. Design: For this,24 rabbits were used and in each calvarium two surgical bone defect were prepared, one on the right side and another on the left side of the parietal suture. The animals were divided into two groups. In group I the experimental defect (right side) was filled with polyurethane derived from oil of the castor oil plant, while in group II the experimental cavity was filled with demineralized bone matrix of human origin. The control cavities were just filled with the bloodof the animal. The animals were sacrificed in the postoperative period at 04, 07 and 15 weeks. Results. The statistical analysis, which was based on the data of the histometric study, showed larger bone neoformation in groups I and II in relation to the control groups, and there were no statistical differences when the experimental groups were compared. Conclusions. The use of polyurethane resinimplants and demineralized human bone matrix helped and optimized the regeneration process when compared with naturalbone regeneration, and similar behavior was obtained without statistical differences in both materials (AU)

Bases fisiológicas de la regeneración ósea I. Histología y fisiología del tejido óseo / Physiological bases of bone regeneration I. Histology and physiology of bone tissue

El hueso es el único tejido del organismo capaz de regenerarse, permitiendo la restitutio ad integrum tras el trauma. Cuando se produce una fractura, se coloca un implante osteointegrado o se realiza un injerto para aumentar el sustrato óseo antes de la inserción de implantes, lo que se pretende es la regeneración ósea, es decir, la formación de hueso nuevo que, tras un proceso de remodelado, sea idéntico al preexistente.El hueso es un tejido dinámico en constante formación y reabsorción. Este fenómeno equilibrado, denominado proceso de remodelado, permite la renovación de un 5-15 % del hueso total al año en condiciones normales (1). El remodelado óseo consisteen la reabsorción de una cantidad determinada de hueso llevada a cabo por los osteoclastos, así como la formación de la matriz osteoide por los osteoblastos y su posterior mineralización. Este fenómeno tiene lugar en pequeñas áreas de la cortical o de la superficie trabecular, llamadas “unidades básicas de remodelado óseo”.La actuación terapéutica en los campos de la Traumatología y Ortopedia, Cirugía Oral y Maxilofacial e Implantología, se asienta sobre los principios biológicos de la regeneración ósea, en los que están implicados células, matriz extracelular y señales osteoinductivas. El objetivo de este trabajo es realizar una puesta al día de los conocimientos actuales sobre los mecanismos bioquímicos y fisiológicos de la regeneración ósea, resaltando de manera especial el papel que en ella juegan las células y las proteínas de la matriz ósea

Bone is the only body tissue capable of regeneration, allowing the restitutio ad integrum following trauma. In the event of a fracture or bone graft, new bone is formed, which following the remodeling process is identical to the pre-existing.Bone is a dynamic tissue in constant formation and resorption. This balanced phenomena, known as the remodeling process, allows the renovation of 5-15% of the total bone mass per year under normal conditions (1). Bone remodeling consists of the resorption of a certain amount of bone by osteoclasts, likewise the formation of osteoid matrix by osteoblasts, and its subsequentmineralization. This phenomenon occurs in small areas of the cortical bone or the trabecular surface, called “Basic Multicellular Units” (BMU). Treatment in Traumatology, Orthopedics, Implantology, and Maxillofacial and Oral Surgery, is based on the biologic principals of bone regeneration, in which cells, extracellular matrix, and osteoinductive signals are involved.The aim of this paper is to provide an up date on current knowledge on the biochemical and physiological mechanisms of bone regeneration, paying particular attention to the role played by the cells and proteins of the bone matrix

Emdogain: últimos avances en regeneración periodontal / Emdogain: an update in periodontal regeneration

Emdogain es un compuesto de proteínas derivadas de la matriz del esmalte, capaz de inducir la regeneración verdadera del aparato de inserción. Como principal indicación destaca el tratamiento de defectos infraóseos, ganancia de hueso y reducción de la profundidad de sondaje con mínima recesión gingival. Es un procedimiento técnicamente simple, con poco riesgo y menos invasivo que las técnicas de regeneración convencionales. La cuidada selección del paciente, el empleo de una técnica adecuada así como el riguroso control postoperatorio son factores importantes para el éxito del tratamiento (AU)

Emdogain is a compound of proteins derived from the enamel matrix which are a crucial factor in initiating the formation of a cellular root cementum and stimulate the development of the periodontal ligament and alveolar bone. The main indication for the application of EMD is the intrabony defects treatment with significant clinical attachment level gains, probing depht reductions and minimal gingival recession. The application of EMD is a simple procedure with less risk than other techniques and less invasive than conventional guided tissue regeneration. A careful selection of the patient, the use of an adecuate technique and the strict postoperatory control are all very important factors for the treatment success (AU)