Microscopic and radiographic analysis of the effect of particle size of demineralized bovine cancellous bone matrix on the repair of bone defects in femurs of rabbits

Abstract

he bone tissue has a great regenerative potential, with ability to completely restore its structure and original functions. In some situations, though, bone defects cannot be self-repaired, thus requiring the use of grafts for a correct treatment and good prognosis. This work aimed at microscopically analyzing the effect of the particle size of demineralized bovine cancellous bone matrix in micro and macrogranular forms on the repair of bone defects in femurs of rabbits, with blood clot used as control. At 1, 3 and 6 months after implantation of the materials, the animals were killed and the anatomic specimens were removed. A foreign body-type granulomatous reaction containing macrophages and multinucleated giant cells in contact with the implanted particles was observed. These results suggest a failure in demineralization and/or interruption of the antigenic potential during production of the biomaterial. It is concluded that the size of the particles did not influence the evolution of the repair process of bone defects, acting only as bone-filler substances, and that the material implanted should be improved by quality control during production, since it may represent a good alternative for bone graft. Uniterms: Xenogenic graft; Bovine cancellous bone; Particle size; Femur; Rabbit. tecido ósseo possui grande potencial regenerativo com capacidade para restaurar completamente sua estrutura e função originais. Há situações em que os defeitos ósseos não conseguem por si só obter o reparo, casos em que se fazem necessários o uso de enxertos, para um correto tratamento e bom prognóstico. Este experimento teve o propósito de analisar microscopicamente o efeito do tamanho das partículas de matriz de osso medular bovino desmineralizado, nas formas micro e macrogranular, na reparação de defeito ósseo em fêmures de coelhos, tendo como controle o coágulo sanguíneo. Após 1,3 e 6 meses da implantação dos materiais, os animais foram mortos e as peças anatômicas removidas. Uma reação granulomatosa tipo corpo estranho, envolvendo as partículas implantadas, foi observada. Estes resultados sugerem falhas na desmineralização e/ou na retirada de potenciais antigênicos durante a produção do biomaterial. Podemos concluir que o tamanho das partículas não influenciou na evolução do processo reparativo dos defeitos ósseos, atuando apenas como substâncias osteopreenchedoras e que o material implantado deverá sofrer um aprimoramento no controle de qualidade na linha de produção, uma vez que poderá representar uma boa alternativa para enxertos ósseos. Unitermos: Enxerto xenogênico; Osso medular bovino; Tamanho de partícula; Fêmur; Coelhos. 2005; 13(2): 157-62 J Appl Oral Sci

Hydroxyapatite crystallinity does not affect the repair of critical size bone defects

“…Critical size defect varies in relation to the animal species, localization and animal age; in rat calvaria bone defect of 5 mm 4 and 8 mm 10 have been widely used. Based on our results, this work supports previous studies that concluded that bone defects of 8 mm diameter did not allow self regeneration up to six months 5,24 .…”

“…The factors affecting the dissolution properties are similar to those affecting biodegradation or bioresorption 5,12,17 .…”

Influence of the association between simvastatin and demineralized bovine bone matrix on bone repair in rats

“…A more intense initial inflammation might be related to factors such as incomplete decalcification of the graft, residual lipids or immunopathological features of the recipient. 18 In the present study, the association between inflammation and DBBM resorption in the first 30 days might have affected the osteoconductivity of DBBM. On postoperative day 60, when DBBM was no longer present, no significant differences were observed between groups DBBM and control.…”

“…16 We were unable to confirm the beneficial properties of DBBM. 15,17 Carneiro et al 18 also investigated the beneficial effects of DBBM and reported no significant differences between the treatment group and the control group. In the present study, DBBM delayed bone matrix formation in the first 30 days, exacerbating the inflammatory process.…”

Estudo comparativo da resistência mecânica da força de compressão entre biomateriais naturais, sintéticos e mistos

“…Eles podem ser obtidos a partir de animais da mesma espécie, ou seja, biomaterial alógeno, ou de espécie diferente, isto é, biomaterial heterógeno. Apesar de serem biologicamente inferiores ao biomaterial autógeno, eles têm sido bastante utilizados na ortopedia reparadora, com resultados satisfatórios (Lane & Sandhu 1987, Moraes et al 2004, Tadjoedin et al 2003, Carneiro et al 2005, Freitas et al 2008. As falhas ósseas também podem ser completa e eficientemente preenchidas por biomateriais sintéticos, como polimetilmetacrilato (Kawano et al 1998, Weinfeld et al 1999, Rahal et al 2000, Braz et al 2003, Moreira et al 2014.…”