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| Author(s): |
Roberto Silveira Fecchio
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD) |
| Defense date: | 2011-02-07 |
| Examining board members: |
Marco Antonio Gioso;
José Luiz Catão Dias;
Carlos Roberto Teixeira
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| Advisor: | Marco Antonio Gioso |
| Abstract | |
The objective was to study the biomechanics of the adherence of adhesive systems to the horny stratum of the toucan beak (Ramphastos toco). Nine different types of adhesives were used, in pre-established areas of 16,0 mm. Each system was studied three times, totaling twenty-seven biomechanical essays. The essays consisted of the analysis of the necessary perpendicular forces to remove the adhesives. After each essay, the surface of the beaks was evaluated in electronic microscopy (MEV), which allowed to measure the amount of remaining resin and eventual breaking of the superficial layers of keratin. The results obtained until complete rupture of the sample were, on average: 2,48 N with the use of resinous cement; 23, 80 N with the use of surgical cyanocrylate; 26,17 N with the use of photoactived primer and bond combined with resinous cement; 48,75 N with the use of composite nanoresin; 53,86 N with the use of methyl-metacrylate; 55,56 N with the use of photoactived primer and bond combined with composite nanoresin; 61,11 N with the combined use of surgical cyanocrylate and methyl-metacrylate; 104, 21 N with the use of primer and bond chemically activated combined with composite nanoresin; and 110,48 N with the use primer and bond chemically activated combined with resinous cement. The microscopy evidenced that the use of primer and bond chemically activated combined with composite nanoresin and resinous cement, showed effective adherence to the point of extracting the superficial layers from the keratin layers after the essays. The largest adherence is attributed to the micro-retentivity of the adhesive material to the keratin layers, obtained by the use of primer and bond chemically activated. It was concluded that the systems of primer and bond chemically activated combined with resin and resinous cement present better properties of adherence and, therefore, clinical-surgical indication in the prostheses construction and in beak repair of toucans (Ramphastos toco). (AU) | |