Estudo histomorfométrico do processo de cicatrização óssea em defeitos cirúrgicos de camanho crítico em calvárias de ratos preenchidos com polímero de mamona

Objectives: The aim of this study was to evaluate the behavior of the polymer histomorphometrically castor during the healing process of defects of critical size calvarial preparations in rats. Materials and Methods: Twenty animals underwent a surgical procedure that was to be held in the calvaria of each animal a critical defect of 8 mm in diameter with a drill trephine. The rats were divided into two groups according to the following procedures: group C received no treatment and the bone defect site was filled with blood clot, group M, the bone defect was filled with castor oil polymer particles. The animals were sacrificed 180 days after the surgical procedures. After routine laboratory procedures the specimens were subjected to analysis histomorphometric. Results: In groups C the newly formed bone tissue was well developed, with adjacent areas of osteoid matrix rich in osteoblasts, and restricted to the vicinity of the edges of the defect. In animals of group M was observed newly formed lamellar bone tissue restricted to the vicinity of the defect edges and particles of polymer Castor distributed throughout the defect. There was a higher percentage of newly formed bone area was statistically significant in group C compared to animals in group M. Conclusions: Within the limits of this study can conclude that the castor oil polymer is biocompatible and had kept the area during the healing of critical size defects in surgically prepared rat calvariae.

Estudo histomorfométrico do processo de cicatrização óssea em defeitos cirúrgicos de tamanho crítico em calvárias de ratos preenchidos com polímero de mamona

Objectives: The aim of this study was to evaluate the behavior of the polymer histomorphometrically castor during the healing process of defects of critical size calvarial preparations in rats. Materials and Methods: Twenty animals underwent a surgical procedure that was to be held in the calvaria of each animal a critical defect of 8 mm in diameter with a drill trephine. The rats were divided into two groups according to the following procedures: group C received no treatment and the bone defect site was filled with blood clot, group M, the bone defect was filled with castor oil polymer particles. The animals were sacrificed 180 days after the surgical procedures. After routine laboratory procedures the specimens were subjected to analysis histomorphometric. Results: In groups C the newly formed bone tissue was well developed, with adjacent areas of osteoid matrix rich in osteoblasts, and restricted to the vicinity of the edges of the defect. In animals of group M was observed newly formed lamellar bone tissue restricted to the vicinity of the defect edges and particles of polymer Castor distributed throughout the defect. There was a higher percentage of newly formed bone area was statistically significant in group C compared to animals in group M. Conclusions: Within the limits of this study can conclude that the castor oil polymer is biocompatible and had kept the area during the healing of critical size defects in surgically prepared rat calvariae

A proporção de plasma rico em plaquetas/enxerto ósseo autógeno pode influenciar o reparo ósseo de defeito de tamanho crítico: estudo radiográfico em calvária de ratos

Introduction: It has been suggested that bone grafts combined with platelet rich plasma (PRP) present greater density than bone grafts without PRP after healing process. However, this result may depend on proportion PRP/autogenous bone (AB) graft used. Objective: The purpose of this study was to analyze radiographically the influence of the proportion PRP/particulate autogenous bone (AB) graft on bone healing in surgically created criticalsize defects (CSD) in rat calvaria. Material and method: 50 rats were divided into 5 groups: C, AB, AB/PRP-50, AB/PRP-100 and AB/PRP-150. A 5 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group AB the defect was filled with 0.01 mL of AB graft. In groups AB/ RP-50, AB/PRP-100 and AB/PRP-150 the defects were filled with 0.01 mL of AB graft combined with 50, 100 and 150 µL of PRP, respectively. All animals were euthanized at 30 days post-operative. Standardized radiographic images of the rat calvaria were obtained using Digora System (Soredex, Finland). The images were evaluated by three examiners using scores that indicated the percentage of radiopacity of the defect. The obtained data were subjected to statistical analysis (Kruskal-Wallis test, p < 0.05). Result: Group C presented radiopacity significantly lower than groups AB, AB/PRP-50, AB/PRP-100 and AB/PRP-150. Group AB/PRP-50 showed radiopacity significantly greater than groups AB/PRP-100 and AB. Conclusion: It can be concluded that the proportion PRP/AB graft influences bone healing in CSD in rat calvaria.

Osteotomia com brocas de alta e baixa rotação, com e sem refrigeração líquida: estudo histopatológico duplo cego em suínos

Nine swines of the White Large race were used for study of the process of bony repair after osteotomy with rotating instruments of low and high-speed, with and without liquid refrigeration. The authors observed, through double blind histopathological analysis, that in every analyzed operative time, the bony repair was processed more appropriately when the osteotomies were accomplished with liquid refrigeration. In the final postoperative times, of fourteen and twenty-eight days, the best results of bony repair were observed in the osteotomy accomplished with drills of low rotation and with liquid refrigeration, while in the postoperative time of seven days, the results of the bony repair of osteotomy accomplished with drills of high rotation and with liquid refrigeration they were better. The authors consider, still, that the process of bony repair in swine display larger proximity in the histological pictures among the studied variables, when compared with other biological models. As most of the works told in the literature it refers the use of dogs, the authors consider that the present work guarantees your importance in the sense of looking for a closer model of the man.

Scaffold nanoestruturado utilizando-se celulose bacteriana/fosfatos de cálcio para regeneração óssea

Pós-graduação em Biotecnologia - IQ

Cimentos bioativos injetáveis funcionalizados com peptídeo osteogênico para reparação óssea

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação in vivo do efeitos do osso bovino desproteinizado revestido com estrôncio sobre o reparo ósseo

Pós-graduação em Ciências Odontológicas - FOAR

Análises físico-químicas e biológicas de diferentes scaffolds à base de polihidroxibutirato e polihidroxibutirato-co-valerato

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anterior Tooth Rehabilitation With Frozen Homogenous Bone Graft and Immediately Loaded Titanium Implant Using Computer-Guided Surgery

Computed tomographic scanning is a precise, noinvasive surveying technique that enables the professionals to improve the precision of implant placement by building a prototype that allows the confection of surgical guides. The authors present a clinical case of anterior tooth rehabilitation with frozen homogenous bone graft and immediately loaded titanium implant using computer-guided surgery. A multislice computed tomography was realized, and a prototype was built. All the procedures were previously realized in the prototype before started in the patient. This technique allows a better surgical planning, makes the procedures more accurate, and reduces surgery time.

Microscopic Evidences That Bone Marrow Mononuclear Cell Treatment Improves Sciatic Nerve Regeneration After Neurorrhaphy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Guided implant surgery: What is the influence of this new technique on bone cell viability?

Purpose: To evaluate the effect of implant osteotomy on immediate bone cell viability, comparing guided surgery for implant placement with the classic drilling procedure. Materials and Methods: For this study, 20 rabbits were used. The animals were divided into a guided surgery group (GG) and a control group (CG) and were then divided into 4 subgroups - subgroups 1, 2, 3, and 4 - corresponding to drills used 10, 20, 30, and 40 times, respectively. All animals received 5 osteotomies in each tibia, by use of the classic drilling procedure in one tibia and guided surgery in the other tibia. The osteotomized areas were removed and processed immunohistochemically for detection of osteocalcin, receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), and caspase 3. Results: Immunohistochemical analysis showed that osteocalcin expression was initially higher in the CG and remained constant after drill reutilization. Although the expressions of RANKL and OPG were not statistically different for the GG and CG, the RANKL/OPG ratio tended to be higher for the GG. Moreover, caspase 3 expression was elevated in the GG, proportionally to the number of osteotomies, indicating an increase in the apoptosis index in the GG. Conclusions: The classic drilling procedure is more favorable to cell viability than guided surgery.© 2013 American Association of Oral and Maxillofacial Surgeons.

Evaluation of Bone Heating, Drill Deformation, and Drill Roughness After Implant Osteotomy: Guided Surgery and Classic Drilling Procedure

Purpose: This study evaluated and compared bone heating, drill deformation, and drill roughness after several implant osteotomies in the guided surgery technique and the classic drilling procedure. Materials and Methods: The tibias of 20 rabbits were used. The animals were divided into a guided surgery group (GG) and a control group (CG); subgroups were then designated (G0, G1, G2, G3, and G4, corresponding to drills used 0, 10, 20, 30 and 40 times, respectively). Each animal received 10 sequential osteotomies (5 in each tibia) with each technique. Thermal changes were quantified, drill roughness was measured, and the drills were subjected to scanning electron microscopy. Results: Bone temperature generated by drilling was significantly higher in the GG than in the CG. Drill deformation in the GG and CG increased with drill use, and in the CG a significant difference between GO and groups G3 and G4 was observed. In the GG, a significant difference between GO and all other groups was found. For GG versus CG, a significant difference was found in the 40th osteotomy. Drill roughness in both groups was progressive in accordance with increased use, but there was no statistically significant difference between subgroups or between GG and CG overall. Conclusion: During preparation of implant osteotomies, the guided surgery technique generated a higher bone temperature and deformed drills more than the classic drilling procedure. The increase in tissue temperature was directly proportional to the number of times drills were used, but neither technique generated critical necrosis-inducing temperatures. Drill deformation was directly proportional to the number of times the drills were used. The roughness of the drills was directly proportional to the number of reuses in both groups but tended to be higher in the GG group.

Cellular behavior as a dynamic field for exploring bone bioengineering: A closer look at cell-biomaterial interface

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro cultivation of canine multipotent mesenchymal stromal cells on collagen membranes treated with hyaluronic acid for cell therapy and tissue regeneration

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Computer-Guided Surgery in Implantology: Review of Basic Concepts

The aim of the present study was to conduct a critical literature review about the technique of computer-guided surgery in implantology to highlight the indications, purposes, immediate loading of implants and complications, protocol of fabrication, and functioning of virtual planning software. This literature review was based on OLDMEDLINE and MEDLINE databases from 2002 to 2010 using the key words "computer-guided surgery" and "implant-supported prosthesis." Thirty-four studies regarding this topic were found. According to the literature review, it was concluded that the computer-assisted surgery is an excellent treatment alternative for patients with appropriate bone quantity for implant insertion in complete and partially edentulous arches. The Procera Nobel Guide software (Nobel Biocare) was the most common software used by the authors. In addition, the flapless surgery is advantageous for positioning of implants but with accurate indication. Although the computer-guided surgery may be helpful for virtual planning of cases with severe bone resorption, the conventional surgical technique is more appropriate. The surgical guide is important for insertion of the implants regardless of the surgical technique, and the success of immediate loading after computer-guided surgery depends on the accuracy of clinical and/or laboratorial steps.