Clinical and Histological Evaluation of a Granular Bovine Bone Biomaterial Used as an Adjunct to Guided Tissue Regeneration With a Bioresorbable Bovine Pericardium Collagen Membrane in the Treatment of Intrabony Periodontal Defects

The aim of the present study is to evaluate the clinical and histologic healing of deep intrabony defects treated with guided tissue regeneration (GTR) with a collagen membrane from bovine pericardium and implantation of granular bovine bone biomaterial.

Measurement of thrombopoietic activity through the quantification of megakaryocytes in bone marrow cytology and reticulated platelets

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

Tibial segmental bone defect treated with bone plate and cage filled with either xenogeneic composite or autologous cortical bone graft

Tibia segmental defect healing in sheep were clinically, radiographically and histologically evaluated. Twelve young sheep aged four to five months were divided into two groups, G1 and G2. A 3.5 cm long segmental defect was created in the right tibial diaphysis with maintenance of the periosteum. The bone defects in both groups were stabilized with a bone plate combined with a titanium cage. In G1 the cage was filled with pieces of autologous cortical bone graft. In G2 it was filled with a composite biomaterial which consisted of inorganic bovine bone, demineralized bovine bone, a pool of bovine bone morphogenetic proteins bound to absorbable ultra-thin powdered hydroxyapatiteand bone-derived denaturized collagen. Except for one G1 animal, all of them showed normal limb function 60 days after surgery. Radiographic examination showed initial formation of periosteal callus in both groups at osteo-tomy sites, over the plate or cage 15 days postoperatively. At 60 and 90 days callus remodeling occurred. Histological and morphometric analysis at 90 days after surgery showed that the quantity of implanted materials in G1 and G2 were similar, and the quantity of new bone formation was less (p = 0.0048) and more immature in G1 than G2, occupying 51 +/- 3.46% and 62 +/- 6.26% of the cage space, respectively. These results suggest that the composite biomaterial tested was a good alternative to autologous cartical bone graft in this experimental ovine tibial defect. However, additional evaluation is warranted prior to its clinical usage.

Comparison between polyurethanes containing castor oil (Soft Segment) and cancellous bone autograft in the treatment of segmental bone defect induced in rabbits

The aim of this study is to compare polyurethanes containing castor oil (soft segment) in granular form compared to cancellous bone autograft applied to a segmental bone defect. Norfolk adult female rabbits - approximately 13 months of age with a mean body weight of 4.5 kg - are used. In both radial diaphyses, 1 cm osteoperiosteal segmental defects are created. The defect in the left radius is filled with the castor-oil-based polyurethane, and the right one, filled with cancellous bone autograft, collected from the left proximal humerus. The rabbits are euthanazed at 15, 30, 60, and 120 days postsurgery (5 animals/ period), for histological analyses. By radiographic analyses, at these time points, the bone regeneration is more evident and accelerated in the bone defects treated with the cancellous bone autograft. At 120 days postsurgery, the segmental bone defects treated with the cancellous bone autograft are totally reconstituted and remodeled, while the bone defects treated with polyurethane polymer have bone formation of 79%. Histological study shows that the polyurethane acts as a space filler, minimizing the local production of fibrous tissue. No granule degradation, resorption or any inflammatory reaction is detected. Thus, it is possible to conclude that the castor-oil-plant-based polyurethane - in the granule presentation - is biocompatible and osteointegrated, but does not show the same bone regeneration capacity as the cancellous bone autograft. © 2007 SAGE Publications.

Osso esponjoso liofilizado de cão utilizado como enxerto puro e associado a plasma rico em plaquetas ou medula óssea em falhas ósseas induzidas em coelhos: estudo experimental

Pós-graduação em Cirurgia Veterinária - FCAV

Utilização de plasma rico ou pobre em plaquetas, associado ou não a enxerto ósseo cortical alógeno, na reparação cirúrgica de falha ulnar em ovinos

Pós-graduação em Cirurgia Veterinária - FCAV

Plasma rico em plaquetas associado a enxerto ósseo autógeno e a membrana absorvível no tratamento de lesões de furca grau III: estudo histomorfométrico em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do plasma rico em plaquetas no tratamento de defeitos ósseos e lesões periodontais de furca grau II. Estudos histológico e histomorfométrico em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Plasma rico em plaquetas, medula óssea ou quitosana nas osteossínteses minimamente invasivas na tíbia de cães

Pós-graduação em Cirurgia Veterinária - FCAV

New LLLT protocol to speed up the bone healing process-histometric and immunohistochemical analysis in rat calvarial bone defect

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reconstruction of alveolar bone defect with autogenous bone particles and osseointegrated implants: histologic analysis and 10 years monitoring

Maintaining the volume of the alveolar process after extraction can be achieved by immediate implant placement and guided bone regeneration, with or without the use of biomaterials. The authors present a case report with a 10 years follow-up, rehabilitation using osseointegrated implants in the extraction area and maintenance of the volume of the alveolar process with autogenous cortical bone shavings.

The Influence of PRP on Early Bone Formation in Membrane Protected Defects. A Histological and Histomorphometric Study in the Rabbit Calvaria

Platelet rich plasma (PRP) has been proposed to be a useful adjunct to bone grafting.

The effect of a slow mode of BMP-2 delivery on the inflammatory response provoked by bone-defect-filling polymeric scaffolds

We investigated the inflammatory response to, and the osteoinductive efficacies of, four polymers (collagen, Ethisorb, PLGA and Polyactive) that bore either an adsorbed (fast-release kinetics) or a calcium-phosphate-coating-incorporated (slow-release kinetics) depot of BMP-2. Titanium-plate-supported discs of each polymer (n = 6 per group) were implanted at an ectopic (subcutaneous) ossification site in rats (n = 48). Five weeks later, they were retrieved for a histomorphometric analysis of the volumes of ectopic bone and foreign-body giant cells (a gauge of inflammatory reactivity), and the degree of polymer degradation. For each polymer, the osteoinductive efficacy of BMP-2 was higher when it was incorporated into a coating than when it was directly adsorbed onto the material. This mode of BMP-2 carriage was consistently associated with an attenuation of the inflammatory response. For coated materials, the volume density of foreign-body giant cells was inversely correlated with the volume density of bone (r(2) = 0.96), and the volume density of bone was directly proportional to the surface-area density of the polymer (r(2) = 0.97). Following coating degradation, other competitive factors, such as the biocompatibility and the biodegradability of the polymer itself, came into play.

A aplicação de plasma rico em plaquetas na regeneração dos tecidos periodontais

O periodonto é uma unidade biológica e funcional, constituída pela gengiva, pelo cemento, pelo ligamento periodontal e pelo osso alveolar. O seu processo de cicatrização envolve mecanismos fisiológicos complexos que requerem a ação dos fatores de crescimento, péptidos oriundos da desgranulação das plaquetas. Neste sentido surge o Plasma Rico em Plaquetas como um produto autólogo, obtido a partir da centrifugação do sangue do próprio paciente e que visa melhorar a cicatrização dos tecidos após procedimentos enquadrados na Medicina Dentária. Esta revisão bibliográfica baseou-se numa pesquisa realizada na base de dados MEDLINE, via pubmed. Foram utilizadas as palavras-chave “plasma rich in growth factors”, “platelet-rich plasma”, “oral surgery”, “dental implants”, “sinus lift”, “third molar surgery” e “bone regeneration”. Após leitura de 40 artigos, foram descartados 9 pela sua pouca relevância no contexto. O objetivo é avaliar a efetividade da aplicação de plasma rico em plaquetas na regeneração dos tecidos periodontais em situações clínicas como alvéolos pós-extracionais, cirurgias de implantes, cirurgias de elevação do seio maxilar e na regeneração óssea. A efetividade em tecidos moles parece ser consensual. A efetividade no tecido ósseo é alvo de contradição entre os diversos autores, concluindo-se que há necessidade de mais estudos randomizados e controlados para que se possa responder à questão com evidência científica suficiente.

Application of Low-Level Laser Irradiation (LLLI) and rhBMP-2 in Critical Bone Defect of Ovariectomized Rats: Histomorphometric Evaluation

Objectives: The aim of this study was to evaluate the osteogenic potential of recombinant human bone morphogenetic protein-2 (rhBMP-2) and low-level laser irradiation (LLLI), isolated or combined in critical bone defects (5mm) in parietal bone using ovariectomized female rats as an experimental animal model. Materials and Methods: Forty-nine female Wistar rats, bilaterally ovariectomized (OVX), were divided into seven treatment groups of seven animals each: (I) laser in a single application, (II) 7 mu g of pure rhBMP-2, (III) laser and 7 mu g of pure rhBMP-2, (IV) 7 mu g of rhBMP-2/monoolein gel, (V) laser and 7 mu g of rhBMP-2/monoolein gel, (VI) laser and pure monoolein gel, and (VII) critical bone defect controls. The low-level laser source used was a gallium aluminum arsenide semiconductor diode laser device (lambda = 780 nm, D = 120 J/cm(2)). Results: Groups II and III presented higher levels of newly formed bone than all other groups with levels of 40.57% and 40.39%, respectively (p < 0.05). The levels of newly formed bone of groups I, IV, V, and VI were similar with levels of 29.67%, 25.75%, 27.75%, and 30.64%, respectively (p > 0.05). The area of new bone formation in group VII was 20.96%, which is significantly lower than groups I, II, III, and VI. Conclusions: It was concluded that pure rhBMP-2 and a single dose of laser application stimulated new bone formation, but the new bone formation area was significantly increased when only rhBMP-2 was used. Additionally, the laser application in combination with other treatments did not influence the bone formation area.