RESUMO
Laminin-1 has been reported as one of the factors responsible for the nucleation of calcium phosphates and, in vitro, has been reported to selectively recruit osteoprogenitors. This article focused on its in vivo effects, and evaluated the effect of laminin-1 local application on osseointegration. Polished cylindrical hydroxyapatite implants were coated with laminin-1 (test) and the bone responses in the rabbit tibiae after 2 and 4 weeks were evaluated and compared to the non-coated implants (control). Before the samples were processed for histological sectioning, they were three-dimensionally analysed with micro computed tomography (µCT). Both evaluation methods were analysed with regards to bone area around the implant and bone to implant contact. From the histologic observation, new bone formation around the laminin-1 coated implant at 2 weeks seemed to have increased the amount of supporting bone around the implant, however, at 4 weeks, the two groups presented no notable differences. The two-dimensional and three-dimensional morphometric evaluation revealed that both histologic and three-dimensional analysis showed some tendency in favour of the test group implants, however there was no statistical significance between the test and control group results.
Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Laminina/farmacologia , Osseointegração/efeitos dos fármacos , Adsorção , Animais , Desenho Assistido por Computador , Corrosão Dentária/métodos , Diamante/química , Durapatita/química , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Interferometria/métodos , Masculino , Osteogênese/efeitos dos fármacos , Coelhos , Propriedades de Superfície , Tíbia/efeitos dos fármacos , Tíbia/patologia , Fatores de Tempo , Microtomografia por Raio-X/métodosRESUMO
A 19 year old man presented with a six months history of dyspnoea on exertion. Chest radiographs, isotopic lung scans, and computed tomographic scans of the chest showed unilateral translucency of the left lung, absence of ventilation and perfusion in the same lung, and a 3.5 cm aneurysm of the descending thoracic aorta which compressed the left mainstem bronchus.