Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-17T13:12:44Z No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-18T15:34:49Z (GMT) No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) / Made available in DSpace on 2017-07-18T15:34:49Z (GMT). No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) Previous issue date: 2017-02-23 / O laser de baixa intensidade (LBI) tem apresentado resultados positivos na prolifera??o de diversos tipos celulares in vitro. A primeira parte do trabalho avaliou o efeito do LBI na prolifera??o e viabilidade de c?lulas-tronco da polpa de dentes dec?duos humanos esfoliados (SHED). As c?lulas foram irradiadas ou n?o (controle) com um laser diodo InGaAlP (660 nm, 30 mW, modo de a??o cont?nuo) usando duas diferentes doses (0,5 J/cm2 por 16 segundos e 1,0 J/cm2 por 33 segundos) e os tr?s grupos foram estudados nos intervalos de 0, 24, 48 e 72 h. Foi observado que a dose de 1,0 J/cm2 promoveu um aumento na prolifera??o celular nos intervalos de 48 e 72 h quando comparada ao grupo controle e ? dose de 0,5 J/cm2 e a viabilidade celular n?o foi afetada pela irradia??o ao longo do experimento. Em conjunto, os dados mostraram que os par?metros do LBI utilizados (660 nm, 30 mW, 1,0 J/cm2) promoveram prolifera??o das SHEDs e mantiveram a sua viabilidade. A partir destes resultados favor?veis, a segunda parte do trabalho avaliou o efeito do LBI com os mesmos par?metros na prolifera??o de SHEDs cultivadas sobre arcabou?os nanofibrosos de PLA confeccionados pela t?cnica de eletrofia??o. Este procedimento permite a obten??o de arcabou?os tridimensionais que simulam a matriz extracelular a partir de um biomaterial com propriedades f?sicas favor?veis e baixo custo. Tr?s grupos experimentais (G1 ? n?o irradiado; G2 ? irradiado com 0,5 J/cm2; G3 ? irradiado com 1,0 J/cm2) foram analisados nos intervalos de 24, 48 e 72 h. Os resultados indicaram que o PLA n?o ? citot?xico para as SHEDs e que os grupos submetidos ? laserterapia tiveram maior prolifera??o celular quando comparados com o grupo controle n?o irradiado. Com base nos achados, evidenciou-se que as nanofibras de PLA s?o arcabou?os favor?veis para o cultivo de SHEDs e que a laserterapia estimulou a prolifera??o quando aplicada nas c?lulas cultivadas sobre este arcabou?o. Com base nos dados gerais obtidos, conclui-se que a laserterapia nos par?metros avaliados apresenta efeitos bioestimulat?rios nas SHEDs cultivadas tanto na superf?cie padr?o (pl?stico da placa de cultivo) quanto sobre arcabou?os nanoestruturados de PLA. / The low-level laser therapy (LLLT) has been shown positive results in the in vitro proliferation of several cell types. The first part of the study evaluated the effect of LLLT on the proliferation and viability of stem cells from human exfoliated deciduous teeth (SHED).Cells were irradiated or not (control) with an InGaAlP diode laser (660 nm, 30 mW, continuous action mode) using two different doses (0.5 J/cm2 for 16 seconds and 1.0 J/cm2 for 33 seconds) and the three groups were analyzed at the intervals of 0, 24, 48 and 72 h.It was observed that the dose of 1.0 J/cm2 promoted an increase in cell proliferation at the 48 and 72 h intervals when compared to the control group and the dose of 0.5 J/cm2, and that cell viability was not affected by irradiation throughout the experiment. Taken together, the data showed that the LLLT parameters (660 nm, 30 mW, 1.0 J/cm2) promoted proliferation of SHEDs and maintained their viability. Based on these favorable results, the second part of the study evaluated the effect of LLLT with the same parameters on the proliferation of SHEDs cultured on PLA nanofibrous scaffolds obtained by electrospinning. This procedure allows obtaining three-dimensional scaffolds that mimic the extracellular matrix from a biomaterial with favorable physical properties and low cost.Three experimental groups (G1 - non-irradiated; G2 - irradiated with 0.5 J/cm2; G3 - irradiated with 1.0 J/cm2) were analyzed at 24, 48 and 72 h. The results indicated that PLA is not cytotoxic to SHEDs and that the groups submitted to laser therapy had higher cell growth when compared to the nonirradiated control group. Based on these findings, it was shown that PLA nanofibers are favorable scaffolds for the cultivation of SHEDs and that laser therapy stimulated the proliferation when applied to the cells cultured on this scaffold. Based on the general data obtained, it is concluded that the laser therapy in the evaluated parameters has biostimulatory effects on the proliferation of SHEDs on both the standard surface (plastic of the culture plate) and on nanostructured PLA scaffolds.