Detalhes bibliográficos
| Ano de defesa: |
2011 |
| Autor(a) principal: |
Torre, Eliana do Nascimento |
| Orientador(a): |
Etges, Adriana |
| Banca de defesa: |
Não Informado pela instituição |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de Pelotas
|
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Odontologia
|
| Departamento: |
Odontologia
|
| País: |
BR
|
| Palavras-chave em Português: |
|
| Palavras-chave em Inglês: |
|
| Área do conhecimento CNPq: |
|
| Link de acesso: |
https://guaiaca.ufpel.edu.br/handle/123456789/2295
|
Resumo: |
Adhesive fillings are satisfactory on short-term evaluation. However, when the evaluation period of longevity of these fillings is longer, problems with the stability of the polymer formed by the adhesive system and the degradation of collagen forming the hybrid layer provoke a large decrease in the durability of this type of filling. The extracellular matrix metalloproteinases (MMPs) are enzymes, which have been associated with the degradation of collagen present at the hybrid layer. Therefore, the possibility of inhibiting the activity of these enzymes has been considered an important strategy to maintain and increase the longevity of adhesive fillings. Hence, the aim of this work is to evaluate the inhibitory potential of MMPs through the addiction of the monomers with promising characteristics reported in previous studies. These monomers have molecules known as ―kidnappers‖ of bivalent cations. This characteristic is important because the catalytic place of MMPs has zinc and calcium in its constitution. Therefore, the coordination of molecules with the catalytic place of the enzyme would be able to inhibit the activity of the MMPs. Dentine from teeth recently pulled will be used to obtain and purify the MMPs of dentine.. The analysis of MMPs inhibition will be carried out through a zymography. In case of positive results for the inhibition of MMPs, cytotoxicity and genotoxicity tests will be carried out in cellular lineages of human pulp fibroblasts apart from an immortalized lineage of fibroblasts of 3T3/NIH mice. The MTT (bromide 3-(4.5-dimethylthiazol-2-ilo)-2.5-diphenyltetrazolium) colorimetric test will be used to measure the cytotoxicity of the products tested and the test of micronucleus will be used to measure genotoxicity. In all groups the 10mM concentration induced 100% cell death. There was no difference in sensitivity in both strains. Statistically, in relation to the control group/untreated, the monomers were more cytotoxic in HPFs of groups 4 and 5. Similar results were found for the 3T3 lineage, except for group 2, which also showed statistical significance for all concentrations. There was a higher number of micronucleated cells in the groups where the two monomers of intermediate chains longer (PEG200 and PEG400 DMA) were used when compared to control. The results suggest that these two monomers are more cytotoxic and genotoxic. Most of the methacrylate monomers showed considerable but not total inhibition of MMP-2 by zymography. The exception was the PEG200 DMA, which only the concentration of 5 mM inhibited the activity of this gelatinolitic MMP |
