The healing of biologic and synthetic bone implants

Abstract

The aim of the present study was to investigate the osteogenic properties of different types of cancellous bone grafts inserted in large osseous defects in dogs and to compare these with those of sintered hydroxyapatite implants. Fresh cancellous autografts were rapidly revascularized and invariably induced a complete healing of the defect. Frozen and fresh cancellous allografts were largely resorbed, the latter evoking a strong antigenic response in two of the five cases. Sintered hydroxyapatite granules were largely encapsulated in fibrous tissue, neither stimulating nor inhibiting osseous ingrowth. Degradation of the hydroxyapatite implant was not observed.

Bone Grafting and Tibial Tuberosity Advancement

“…In a concurrent clinical study, the tibial graft donor sites in dogs were radiographically osteoporotic for up to 3 years 3 . Similarly, in other studies in the dog 4 ; sheep 5 ; and baboons 6 ; as examples, all evidence pointed to incomplete healing within empty metaphyseal gaps in the distal femur—arguably a site with greater regenerate potential than the proximal tibial metaphysis. In all of these studies, histologic evaluation was obtained to document/quantify the degree of healing.…”

Reconstrução de defeitos ósseos cranianos em ratos com células-tronco de polpa dentária humana: estudo experimental de neoformação óssea

“…Embora alguns estudos evidenciem um sucesso clínico com uso desses enxertos ósseos desmineralizados no reparo de defeitos ósseos, outros autores reportam uma atividade de indução óssea inconsistente (22,23) . Todavia, ao contrário dos enxertos autógenos frescos, que são bem aceitos pelo organismo, sendo rapidamente vascularizados induzindo completa cicatrização do defeito, os aloenxertos congelados e frescos são largamente absorvidos e produzem forte resposta antigênica (24) . Há também O uso de material ósseo proveniente de bancos de tecidos cresceu bastante nos últimos anos; nos Estados Unidos, de uma estimativa de 100.000 casos em 1971 para aproximadamente 250.000 casos em 1991 (25,26) .…”