Bone defect regeneration with bioactive glass implantation in rats

Abstract

he main goal of this study was to histologically evaluate the healing of surgically created defects on the tibiae of adult male rats after implantation of two types of bioactive glass. Sixteen adult Wistar rats (body weight of 300g) were divided into two groups: PerioGlas (PG) (n=8) and BioGran (BG) (n=8). Unicortical bone defects with 3-mm diameter were performed in both tibiae of the animals and filled with two types of glass particles. The rats were then sacrificed at 7, 14, 30 and 60 days, and the tissues were prepared for histological processing, sectioning, and staining with hematoxylin and eosin, as well as Mallory trichrome, and analyzed under light microscope. Within 7-14 days, both groups presented connective tissue septa with new bone formation, more intense in the PG group. In the subsequent periods (30 and 60 days), both groups presented more mature bone tissue around the glass particles. Bone trabeculae formed in all experimental periods were juxtaposed to the glass particles. It can be concluded that both materials promoted comparable bone formation over the entire extension of the defect, independently of the size of the granules, thus confirming their biological osteoconductive property. UNITERMS: Bone regeneration; Bioactive ceramic; Bone repair; Implant; Bioactive glass. objetivo deste estudo foi avaliar a resposta histológica após a implantação de dois tipos de cerâmicas bioativas em defeitos criados na tíbia de ratos. Dezesseis ratos da raça Wistar, pesando 300g, foram divididos em dois grupos: PerioGlass (PG) (n=8) e Biogran (BG) (n=8). Defeitos ósseos unicorticais de 3 mm de diâmetro foram realizados na tíbia dos animais e preenchidos com os dois tipos de partículas cerâmicas. Os animais foram sacrificados aos 7, 14, 30 e 60 dias no pós-operatório. O material preparado para processamento e exame histológico em microscopia óptica foi corado com hematoxilina-eosina e tricrômio de Mallory. Aos 7 dias ambos os grupos apresentaram septos ósseos neoformados, mais intensos no grupo PG. Isto também foi observado aos 14 dias. Nos períodos posteriores (30 e 60 dias), ambos os grupos apresentaram tecido ósseo mais maduro ao redor das partículas cerâmicas. As trabéculas ósseas formadas em todos os períodos experimentais foram justapostas com as partículas. Podemos concluir que ambos os materiais promoveram o preenchimento ósseo em toda a extensão do defeito independente de suas granulações comprovando suas propriedades osteocondutivas.

Bone repair process in calvarial defects using bioactive glass and calcium sulfate barrier

“…Suggestive data on the formation of tissue with bone characteristics, in the central region of the granules, were observed on the 21 st day . This formation was also confirmed by Camargo et al 10 and Macedo et al 5 . Melo 12 , however, affirms that they are simply remains of BG particulates covered by conjunctive tissue.…”

“…In contrast, there was a clear alteration, seen as of the 60 th day, in the morphology of the granules which appeared irregular on the surface and with reduced sizes in relation to the first group (after 7 days). These characteristics suggest the occurrence of the superficial dissolution of the material, described by a number of authors 3,5,12,17,20,22 , where a thick layer of silicon, covered with a thick layer of calcium and phosphate, is formed with a consequent collagenous attraction surrounding it.…”

“…Nevertheless, the need for additional surgery in the donor's area, in contrast with the receptor's area, becomes an inconvenience for many patients who do not accept the intervention in other regions of the body 4,5 .…”

“…The bone glass available in the market is composed of silicon dioxide (SiO 2 ), calcium oxide (CaO), sodium oxide (Na 2 O), and phosphate pentoxide (P 2 O 5 ); it possesses biocompatibility with body tissues, allows for bone migration and the colonization of osteogenic cells on its surface, in addition to presenting a greater capacity for linkage to the bone and soft tissues, when compared to other alloplastic materials 3,5 . The components of disassociation of the material support the formation of new bone, and its glass particles have the capacity of incorporating themselves within the new bone 7 .…”

Evaluation of optical density of bone defects filled with calcium phosphate cement and bioactive glass in rats

“…Of these, calcium phosphate cement (CPC) lists the properties of biocompatibility, bioactivity 1 and osteoconductivity, in addition to easy handling and molding that enable optimal adaptation to the bone defect to be repaired. Bioactive glasses (BG) are silicon-based bone graft substitutes that, in addition to osteoinductive and osteoconductive properties, have pro-angiogenic potential as a result of factors generated by products of its dissolution 2 and great ability to bond to bone and soft tissue 3 . Biomaterials that can substitute bone structures are the current choice in reconstruction, since they prevent patient complications from a possible autogenous donor site, such as inflammation, stiffness, pain, and bacterial infection 4 .…”