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Abstract(s)
A análise quantitativa da integração óssea de implantes metálicos biofuncionalizados é uma ferramenta
importante para o desenvolvimento de implantes com maiores taxas de sucesso, com um elevado
destaque em patologias ósseas, como a osteoporose. Para tal, a Microtomografia Computadorizada
(MicroCT) permite um registo tridimensional (3D) do osso com resolução micrométrica e uma análise
quantitativa de diversos parâmetros ósseos.
Neste trabalho foi testado um novo revestimento para promover a osteointegração de materiais de titânio
(Ti) em animais envelhecidos (ratos). Foram desenhados quatro grupos experimentais: defeito vazio;
implante de Ti; implante de Ti modificado com um péptido antimicrobiano; implante de Ti modificado
com um péptido antimicrobiano e Vesículas Extracelulares (EVs). Os materiais foram implantados num
defeito femoral de tamanho crítico e analisados às duas e às oito semanas após a implantação, por
microCT. Realizou-se uma análise visual qualitativa e análise quantitativa através do software CTAn.
Foram utilizadas EVs de células estaminais mesenquimais (MSC) provenientes de Wharton Jelly (WJMSC EVs) com péptidos antimicrobianos, com o intuito de avaliar o seu potencial para promover a integração
óssea em osso envelhecido.
Após uma análise visual do grupo com defeito vazio, entre a 2ª semana e 8ª semana, observou-se alguma
regeneração óssea, no entanto, sem ocorrer uma regeneração total do defeito crítico, como seria
expectável. Os grupos implantados com materiais de titânio mostraram boa integração, com maior
formação de novo osso na zona circundante do implante, para o grupo implantado com Ti modificado
com péptido e EVs, demonstrando que a utilização destas EVs é promissora, inovadora e viável para
um ambiente local favorável à osteointegração do implante.
The quantitative analysis of the osseointegration of modified titanium (Ti) implants is an important tool for the development of implants with higher success rates in bone pathologies, such as osteoporosis. In this way, Microcomputed Tomography (microCT) allows a three-dimensional (3D) registration of the bone with micrometric resolution and a quantitative analysis of various bone parameters. In this work, a new coating was tested to promote the osseointegration of Ti materials in aged animals (rat). Four experimental groups were designed: empty defect; Ti implant; Ti implant modified with an antimicrobial peptide; Ti implant modified with an antimicrobial peptide and Extracellular Vesicles (EV). The materials were implanted into a critical-sized femoral defect and analyzed at two and eight weeks after implantation, by microCT. A qualitative visual analysis and quantitative analysis were carried out using the CTan software. EVs from mesenchymal cells (MSC) from Wharton Jelly (WJMSC-EVs) with antimicrobial peptides were used, to evaluate their potential to promote bone integration in aged bone. After a visual analysis of the group with an empty defect, between the 2nd week and 8th week, some bone regeneration was observed, however, without total regeneration of the critical defect, as would be expected for the 8th week of implantation. The groups implanted with Ti materials showed good integration, with greater formation of new bone in the area surrounding the implant, compared to the group implanted with peptide-modified titanium and EVs, demonstrating that the use of these EVs is promising, innovative, and viable for an environment favorable location for osseointegration of the implant.
The quantitative analysis of the osseointegration of modified titanium (Ti) implants is an important tool for the development of implants with higher success rates in bone pathologies, such as osteoporosis. In this way, Microcomputed Tomography (microCT) allows a three-dimensional (3D) registration of the bone with micrometric resolution and a quantitative analysis of various bone parameters. In this work, a new coating was tested to promote the osseointegration of Ti materials in aged animals (rat). Four experimental groups were designed: empty defect; Ti implant; Ti implant modified with an antimicrobial peptide; Ti implant modified with an antimicrobial peptide and Extracellular Vesicles (EV). The materials were implanted into a critical-sized femoral defect and analyzed at two and eight weeks after implantation, by microCT. A qualitative visual analysis and quantitative analysis were carried out using the CTan software. EVs from mesenchymal cells (MSC) from Wharton Jelly (WJMSC-EVs) with antimicrobial peptides were used, to evaluate their potential to promote bone integration in aged bone. After a visual analysis of the group with an empty defect, between the 2nd week and 8th week, some bone regeneration was observed, however, without total regeneration of the critical defect, as would be expected for the 8th week of implantation. The groups implanted with Ti materials showed good integration, with greater formation of new bone in the area surrounding the implant, compared to the group implanted with peptide-modified titanium and EVs, demonstrating that the use of these EVs is promising, innovative, and viable for an environment favorable location for osseointegration of the implant.
Description
Keywords
Biomateriais MSCs WJMSC-EVs Implante de Titânio MicroCT Osteointegração