Magister Scientiae Dentium - MSc(Dent) / Objectives:Substances leaching from denture- base polymers have been associated with cytotoxicity and allergic reactions. This study examined the effect of polishing,mixing ratios, water immersion temperatures and different thicknesses on the sorption and solubility of a heat-polymerized, denture-base polymer. The effect of different water immersion temperatures on the flexural strength of the denture base, was tested as well. The next component of this study, is the testing of the most significant sorption and solubility findings on in vitro cell viability. Materials and Methods:Disc shaped specimens from a heat-polymerized, denture-base polymer (Vertex®) were prepared, based on ISO 1567 specifications for sorption and solubility testing, following the manufacturers’ instructions. The following tests were performed: 1) Sorption and solubility of two groups (n = 12 each) of polished and unpolished discs were established and compared by means of the Mixed procedure; 2) Sorption and solubility of three groups (n = 12 each) with different mixing ratios were compared by means of the Mixed procedure; 3) Four groups (n = 14 each) were immersed in water at different temperatures, sorption and solubility were compared by means of pairwise comparison and the Median test; 4) Specimens with different thicknesses (n = 36) were compared, again, by means of pairwise comparison and the Median test; 5) To test the influence of different water-soaking temperatures on the flexural strength of the disc, strips were prepared from the disc used in test no. 3. The flexural strength was compared, by means of the Median test; 6) To test the influence of no postpolymerization treatment, polishing and water immersion on the cytotoxicity of mouse fibroblast cells, (n = 9) for each test group, were prepared. A preliminary test was performed beforehand, over a period of 24 hours, up to a maximum period of four weeks. The Balb/c 3T3 mouse fibroblast cells were cultured and incubated for 24 hours in Eagles medium. Eluates prepared from the disc and medium without any disc (control) replaced the medium. Cytotoxicity was assessed by MTT-assay. Optical density values were obtained at 24 and 48 hour intervals. The data was analyzed by means of the Means procedure.Results:In the entire thesis, the data was analyzed using SAS on a 0.01 probability level.Between polished and unpolished groups, no significant difference in water sorption (p> 0.01) was found, but there was a difference in solubility (p<0.01).Different mixing ratios did not alter sorption (p = 0.34) or solubility (p = 0.68).However, a difference (p<0.01) in sorption and solubility was found among the different temperature and thickness groups. Soaking the denture base in water at different temperatures did not alter its flexural strength (p = 0.48). Cell viability levels were noted in all the experimental groups in the MTT assay test. The analysis was a two-factor study, with one factor being the group, and the other, being time. The interaction between these factors was found to be significant, indicating that the effect of the groups varied by time (and vice versa).Conclusion:The processes of the soaking in warm water and the polishing of a denture-base polymer, reduce its solubility. Therefore, it is recommended that dentures are soaked in warm water before polishing. Within the limits of this study, the mixing ratios may be changed without affecting sorption or solubility. As solubility increases within the increasing denture-base thickness, it is recommended that unnecessarily thick dentures be avoided.Short- and long-term exposure to eluates of a PMMA, has a negative effect on cell viability. For water-stored and polished discs, this effect is time-dependent, with a higher viability for 48 hours’, than for 24 hours eluates. Polishing is associated with lower solubility. At 24 hours, the polished discs, indeed, had a lower cytotoxic effect than the untreated discs: it may be recommended that dentures be polished on the fitting surface as well.The cytotoxic potential of PMMA-eluates appears to fluctuate over time.

Resumo: O presente estudo teve como objetivo avaliar o efeito citotóxico dos monômeros isobutil metacrilato (IBMA) e 1,6 - Hexanediol dimetacrilato (1,6 - HDMA), do plastificante di-n-butil ftalato (DBP), e dos produtos de degradação ácido metacrílico (AM) e ácido benzóico (AB) sobre células L929. Esses compostos foram testados em faixas de concentrações liberadas, em um período de 30 dias, por materiais reembasadores rígidos, previamente quantificadas em estudos anteriores. O efeito citotóxico foi verificado por meio dos testes de MTT e 3H-timidina, após as células terem sido expostas às substâncias testadas nas concentrações estabelecidas. A classificação da citotoxicidade foi baseada na viabilidade celular em relação ao controle (células expostas ao meio sem as substâncias testadas). A atividade de síntese de DNA foi inibida por todos os compostos. Os resultados do presente estudo demonstraram que o teste de 3H-timidina foi mais sensível que o teste de MTT e que os compostos avaliados mostraram diferentes níveis de citotoxicidade in vitro. A atividade da desidrogenase mitocondrial diminuiu nas células tratadas com os monômeros, o plastificante e o produto de degradação AM; porém, para o AB, a maioria das concentrações testadas não apresentou efeito citotóxico. / Abstract: The aim of this study was to evaluate the cytotoxic effect of the monomers 1,6 - hexanediol dimethacrylate (1,6 - HDMA) and isobutyl methacrylate (IBMA), the plasticizer di-n-butyl phthalate (DBP), and the degradation by-products methacrylic acid (MA) and benzoic acid (BA) on L929 cells. These compounds were tested in the range of concentrations released in 30 days from hard chairside reline resins that were quantified in previous investigations. Cytotoxic effects were assessed by using MTT and 3H - thymidine assays after the cells had been exposed to the test compounds at the given concentrations. Cytotoxicity was rated based on cell viability relative to controls (cells exposed to medium without test substances). The results presented in this study demonstrated that the 3H-thymidine assay was more sensitive than the MTT assay, and all compounds tested showed varying degrees of cytotoxic effect in vitro. DNA synthesis activity was inhibited by all compounds. Mitochondrial dehydrogenase activity decreased in cells treated with monomers, plasticizer and MA by-product, whereas no cytotoxic effect was observed on contact with BA at the majority of concentrations tested. / Orientador: Ana Lucia Machado / Coorientador: Iracilda Zeppone Carlos / Banca: Ana Cláudia Pavarina / Banca: Cláudia Lovato da Silva / Mestre

OBJECTIVES: Evaluate the mechanical properties of commercial digital denture base materials. Materials: The materials used were Lucitone 199 denture base disc (Dentsply Sirona), AvaDent denture base puck (AvaDent), KeyMill denture base disc (Keystone), Lucitone digital print denture base resin (Dentsply Sirona), Formlabs denture base resin (Formlabs), and Dentca denture base resin II (Dentca). METHODS: For each material, 60 bar-shaped specimens were prepared for flexural testing, which were divided into 5 groups including control, fatigue, thermocycling, and repairing using 2 types of materials. 24 square-shaped specimens were included in the bond testing, bonded to tooth and composite resin. Additionally, 48 square-shaped specimens were fabricated for the color stability testing, against UV light and staining and washing solutions. The flexural strength and modulus were calculated through 3-point bend test. Bond strength was determined using shear bond test. Color coordinates were recorded in the CIE L*a*b* system using an X-Rite Ci7600 spectrophotometer. Color differences relative to the baseline (∆E^*) were obtained. Data were analyzed using one-way ANOVA followed by Tukey’s HSD test (α=0.05). RESULTS: Milled materials showed higher flexural strength than printed materials. Fatigue and thermocycling led to a decrease in the flexural strength of both group materials. Repaired groups showed flexural strength of about 30.67% and 32.80% of its original strength, in milled and printed materials respectively. However, the flexural strength of the printed materials was affected by the type of the repair material, composite resin gave higher values compared with acrylic. Printed materials exhibited superior bond strength to tooth and composite resin than milled materials. The color change under UV light was clinically acceptable. The color change after immersion in staining and washing solutions in milled groups was less noticeable than in the printed group. Thermocycling treatment made the color change more noticeable in both milled and printed groups. CONCLUSION: Milled denture materials exhibited higher flexural properties than printed denture materials. Printed materials exhibited higher shear bond to tooth and composite resin. The color stability of milled materials with staining and washing solutions treatment was better than the printed groups, whereas the color stability of milled and printed materials exposed to UV light was clinically acceptable. / 2023-08-03T00:00:00Z

No description available.

Four denture base materials of poly(methyl methacrylate) (QC-20, Pladent-20, Hygenic, and Optilon-399) were prepared by convention water bath and microwave-energy cured methods. While the resin was in the dough stage, it was packed into two molds (65 mm ¡¦15 mm ¡¦10 mm) in the fiber reinforced plastic flask. The variation of temperature with time was recorded by two thermocouples during the microwave heating at 80, 160, and 240 watts, respectively. Microwave polymerization was carried out in the same equipment. The microwave flask containing the same size of resin blocks were processed at 80, 160, 240, and 560 watts for 15, 10, 7, and 2 min, separately. Then each flask was turned over, and cured an additional 2 min at 560 watts. In the case of water-bath method, the resin in the dough stage was packed in the Brass flask, and then cured at 70¢J for 9 hours. Ten specimens were prepared for each condition studied. The surface hardness, porosity, flexural properties and solubility of both process conditions were evaluated. The samples were sectioned by microtome and stained 2 % Osmiun tetroxide, then the morphology of Optilon-399 was observed by using TEM (Transmission electron microscopy) at 160 KV. The result indicate that the flexural strength for Optilon-399 specimens prepared by water-bath method was 20 MPa higher than that prepared in microwave oven, however, there were no obvious difference between the samples cured at different power. Phase separation in two different sizes was observed in all of the Optilon-399 specimens. The larger domain was with 0.18 mm~0.67 mm diameter has dispersed rubber phase surrounded by a rubber periphery. The smaller domain with 0.1 mm diameter is rich with rubber phase. The size and distribution of the larger domain were correlated with the microwave power and curing time. The sample cured by water-bath has the largest average domain diameter (0.395¡Ó0.068 mm). In the specimens prepared by microwave method, the domain size decreased with increasing power. In additions, the domain size varied across the specimen. The size difference between the largest and the smallest domain for specimens cured at 80W was 0.03 mm, and that for specimens cured at 560W was 0.05 mm. This indicated that the larger the power watt was, the higher the morphology difference was.

In this study, the thermal and mechanical properties of poly(ethylenetheraphthalate) (PET)-thermotropic liquid crystal polyester (TLCP), mixtures and poly(methyl methacrylate) (PMMA)-TLCP mixtures were studied. The curing of PMMA-TLCP mixtures was done by heat, gamma radiation and microwave. The amount of TLCP in mixtures was % 0.5, 2 and 5 TLCP by weight. TLCP was synthesized by melt-acidolysis system, and PET-TLCP mixtures were prepared by using lab scale batch mixer. PMMA samples were prepared according to denture manufacturer&rsquo / s procedure. The characterization of polymer samples and mixtures were carried by FT-IR, NMR, DSC, DMA, tensile, impact, three point bending tests and light microscopy. The mixing of TLCP with PMMA yielded heterogeneous dispersions. This was observed from light micrographs. The mechanical and rheological properties of all polymers were not positively affected by inclusion of TLCP. It is also worthwhile to note that weakening of PET-TLCP mixtures were due to the thermal degradation as the thermal age of the mixtures is much higher.

Made available in DSpace on 2014-06-11T19:28:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-19Bitstream added on 2014-06-13T20:58:45Z : No. of bitstreams: 1 costa_cc_me_arafo.pdf: 3083928 bytes, checksum: 2605dd91339dbf0d4e3c26e02afc6696 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo deste estudo foi determinar a citotoxicidade in vitro de duas resinas reembasadoras experimentais autopolimerizáveis contendo alta concentração de agentes de ligação cruzada, etilenoglicol dimetacrilato (EGDMA) e 1,4-butanodiol dimetacrilato (BDMA) comparadas com uma resina reembasadora comercial (Tokuyama Rebase Fast II). Foram confeccionados corpos-de-prova em forma de discos das três resinas acrílicas reembasadoras rígidas sob condições assépticas. Os fibroblastos (L929) foram cultivados em placas com 96 compartimentos e incubadas por 24 h em meio de cultura Eagle. Os extratos foram preparados, colocando-se três amostras de cada resina em frascos de vidro estéreis com 9 mL de meio de Eagle e incubadas a 37º C por 24 h. O efeito citotóxico dos extratos foram avaliados utilizando os testes de incorporação do 3H-timidina e MTT, que refletem os níveis de síntese de DNA e metabolismo celular, respectivamente. Os dados foram analisados estatisticamente, utilizando análise de variância (P<0.05). Para o teste de incorporação do 3H-timidina, não foram observadas diferenças significativas (P>0.05) entre os materiais. A média da quantidade do isótopo incorporado no DNA celular para todas as resinas acrílicas foi estatisticamente menor do que para o controle. Todas as resinas acrílicas foram classificadas pelo teste de incorporação do 3Htimidina como moderadamente citotóxicas. Da mesma forma, para o teste do MTT, não foi encontrada diferença significativa para a citotoxicidade entre os materiais (P>0.05). Quando a citotoxidade foi comparado com o grupo controle, todas as resinas foram classificadas entre não citotóxicas e discretamente citotóxicas pelo teste do MTT. Assim, conclui-se que a incorporação dos agentes de ligação cruzada, EGDMA e BDMA não influenciaram significativamente sobre a citotoxicidade observada. Não houve diferença... / The aim of this study was to determine the cytotoxicity in vitro of two trials autopolymerizing reline systems made with higher concentration of cross-linking agents, EGDMA and BDMA compared to a commercial reline resin. Sample disks of the three hard reline acrylic resins were fabricated under aseptic conditions. The Fibroblast L929 cells were cultured in 96-well plates and incubated for 24 h in Eagle's medium. Eluates were prepared by placing three samples into a sterile glass vial with 9 mL of Eagle's medium and incubating at 37ºC for 24 h. The cytotoxic effect from the eluates was evaluated using the 3H-thymidine incorporation and MTT assays, which reflect DNA synthesis levels and cell metabolism, respectively. The data were statistically analyzed by using the one-way analysis of variance (P<.05). With the 3H-thymidine incorporation assay, no significant differences (P > .05) were found between the materials. The mean quantity of isotope incorporated into cellular DNA for all acrylic resins was statistically smaller than for the control. All acrylic resins were graded by the 3Hthymidine incorporation assay as moderate cytotoxic. Similarly, with the MTT assay, no significant difference in cytotoxicity was found between the materials (P > .05). When the cytotoxicity was compared with control group, all resins assay were between non cytotoxic and slight cytotoxic by the MTT. The incorporation of cross-linking agents, EGDMA and BDMA had no significant influence on the cytotoxicity observed. There was no cell viability difference between all materials in both assays.

Submitted by Sâmia Carolina Mota Cavalcanti Sacorague (samiacmc@gmail.com) on 2016-04-01T02:29:04Z No. of bitstreams: 1 Tese Oficial Sacorague.pdf: 138789678 bytes, checksum: 64a0549f6b21193b17f2359358326d21 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-05T16:34:30Z (GMT) No. of bitstreams: 1 sacorague_scm_dr_sjc.pdf: 138789678 bytes, checksum: 64a0549f6b21193b17f2359358326d21 (MD5) / Made available in DSpace on 2016-04-05T16:34:30Z (GMT). No. of bitstreams: 1 sacorague_scm_dr_sjc.pdf: 138789678 bytes, checksum: 64a0549f6b21193b17f2359358326d21 (MD5) Previous issue date: 2016-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desta pesquisa foi sintetizar e caracterizar partículas de sílica recobertas com nanopartículas de prata, e avaliar a influência destas quando incorporadas à resina acrílica termicamente ativada e reembasador rígido, em suas características mecânicas e microbiológicas. Uma solução de sílica foi sintetizada pelo método de hidrólise controlada do tetraetilortosilicato (TEOS) em meio alcoólico. Foi adicionada a essa uma solução de nitrato de prata, em duas molaridades (10 mmols e 30 mmols) formando partículas do tipo núcleo-casca. Após centrifugação e secagem, cada pó obtido foi adicionado em duas concentrações: 0.5% e 2%, às resinas analisadas. Foram confeccionadas barras retangulares (n=9) de 30 x 10x 3mm para realização do teste de resistência a flexão de três pontos, rugosidade e ângulo de contato; e 120 amostras em forma de disco (2 mmx10 mm) para análise microbiológica. Como grupo controle teve-se amostras sem nanopartículas. As nanopartículas foram analisadas em microscopia eletrônica de varredura com microanalisador por energia dispersiva de raios-X integrado (EDS), Difratômetro de Raios-X e microscopia eletrônica de transmissão. Uma suspensão de Candida albicans foi utilizada para análise de aderência fúngica, halo de inibição e concentração inibitória mínima. As fotomicrografias mostraram que as nanopartículas de 10 mmols apresentam uma distribuição mais homogênea e menor agregação das nanopartículas de prata na superfície da sílica do que as de 30 mmols. Os resultados indicaram que a resistência a flexão foi afetada negativamente, em ambos materiais, com a adição de 2% de partículas, independente da molaridade. A adição das partículas não alterou a molhabilidade da superfície dos materiais, nem a rugosidade, exceto do grupo de reembasador com partículas de 10mmols, em ambas concentrações. As partículas não apresentaram ação antifúngica para os materiais testados em nenhuma concentração, nem houve a formação de halo. Entretanto, a solução apresentou concentração inibitória mínima a partir de 2.000 ppm. Concluiu-se que em baixas concentrações as nanopartículas não afetaram as características mecânica e de superfície da resina acrílica e do reembasador, entretanto elas não inibiram a formação de biofilme por C. albicans sob os materiais. / This research aimed to synthesize, characterize, and evaluate the influence of the addition of silica-silver core/shell particles in mechanical and antifungal characteristics of thermally active acrylic resins or hard reliner . Silica solution was produced by controlled hydrolysis method of tetraethylorthosilicate (TEOS) in an alcoholic. It was added a silver nitrate solution in two molarities, 10 and 30 milimols, forming core-shell particles. After centrifugation and drying, each obtained powder was added in two concentrations 0.5% and 2% in the resins analyzed. Rectangular samples (n=9) with 30 x10 x3 mm were made to three point bend test), roughness and contact angle, and 120 samples in disc (2 mmx10 mm) for microbiological analysis Samples without particles were used as control. The nanoparticles were analyzed by scanning electron microscopy with dispersive energy microanalyzer integrated X-rays (EDS), X-ray diffractometer and transmission electron microscopy. Candida albicans suspension was used to adhesion test, inhibition zone and minimum inhibitory concentration. Photomicrograph showed that nanoparticles with 10 milimols show a distribution more uniform and less aggregation of silver nanoparticles on the silica surface than 30 millimols. The Three point bend test results showed that the flexural strength was negatively affected in both materials, with the addition of 2% particles, in both molarity. The addition of the nanoparticles did not change the surface wettability or roughness of the materials, except for except the reliner group with 10mmols, in both concentrations. The nanoparticles showed no antifungal action for the materials tested at any concentration, neither was zone innibition. However, the solution presented minimal inhibitory concentration to 2.000 ppm. We conclude that low concentrations nanoparticles do not affect the mechanical characteristics and surface of the acrylic resin or reliner, however they do not reduce biofilm adhesion by C. albicans in the materials.

Made available in DSpace on 2014-06-11T19:29:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-17Bitstream added on 2014-06-13T19:38:21Z : No. of bitstreams: 1 chaves_cal_me_arafo.pdf: 1976512 bytes, checksum: 337945ed5713a7c6624f79a6e9161818 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente estudo teve como objetivo avaliar o efeito citotóxico dos monômeros isobutil metacrilato (IBMA) e 1,6 – Hexanediol dimetacrilato (1,6 – HDMA), do plastificante di-n-butil ftalato (DBP), e dos produtos de degradação ácido metacrílico (AM) e ácido benzóico (AB) sobre células L929. Esses compostos foram testados em faixas de concentrações liberadas, em um período de 30 dias, por materiais reembasadores rígidos, previamente quantificadas em estudos anteriores. O efeito citotóxico foi verificado por meio dos testes de MTT e 3H-timidina, após as células terem sido expostas às substâncias testadas nas concentrações estabelecidas. A classificação da citotoxicidade foi baseada na viabilidade celular em relação ao controle (células expostas ao meio sem as substâncias testadas). A atividade de síntese de DNA foi inibida por todos os compostos. Os resultados do presente estudo demonstraram que o teste de 3H-timidina foi mais sensível que o teste de MTT e que os compostos avaliados mostraram diferentes níveis de citotoxicidade in vitro. A atividade da desidrogenase mitocondrial diminuiu nas células tratadas com os monômeros, o plastificante e o produto de degradação AM; porém, para o AB, a maioria das concentrações testadas não apresentou efeito citotóxico. / The aim of this study was to evaluate the cytotoxic effect of the monomers 1,6 – hexanediol dimethacrylate (1,6 - HDMA) and isobutyl methacrylate (IBMA), the plasticizer di-n-butyl phthalate (DBP), and the degradation by-products methacrylic acid (MA) and benzoic acid (BA) on L929 cells. These compounds were tested in the range of concentrations released in 30 days from hard chairside reline resins that were quantified in previous investigations. Cytotoxic effects were assessed by using MTT and 3H - thymidine assays after the cells had been exposed to the test compounds at the given concentrations. Cytotoxicity was rated based on cell viability relative to controls (cells exposed to medium without test substances). The results presented in this study demonstrated that the 3H-thymidine assay was more sensitive than the MTT assay, and all compounds tested showed varying degrees of cytotoxic effect in vitro. DNA synthesis activity was inhibited by all compounds. Mitochondrial dehydrogenase activity decreased in cells treated with monomers, plasticizer and MA by-product, whereas no cytotoxic effect was observed on contact with BA at the majority of concentrations tested.

Resumo: O objetivo deste estudo foi determinar a citotoxicidade in vitro de duas resinas reembasadoras experimentais autopolimerizáveis contendo alta concentração de agentes de ligação cruzada, etilenoglicol dimetacrilato (EGDMA) e 1,4-butanodiol dimetacrilato (BDMA) comparadas com uma resina reembasadora comercial (Tokuyama Rebase Fast II). Foram confeccionados corpos-de-prova em forma de discos das três resinas acrílicas reembasadoras rígidas sob condições assépticas. Os fibroblastos (L929) foram cultivados em placas com 96 compartimentos e incubadas por 24 h em meio de cultura Eagle. Os extratos foram preparados, colocando-se três amostras de cada resina em frascos de vidro estéreis com 9 mL de meio de Eagle e incubadas a 37º C por 24 h. O efeito citotóxico dos extratos foram avaliados utilizando os testes de incorporação do 3H-timidina e MTT, que refletem os níveis de síntese de DNA e metabolismo celular, respectivamente. Os dados foram analisados estatisticamente, utilizando análise de variância (P<0.05). Para o teste de incorporação do 3H-timidina, não foram observadas diferenças significativas (P>0.05) entre os materiais. A média da quantidade do isótopo incorporado no DNA celular para todas as resinas acrílicas foi estatisticamente menor do que para o controle. Todas as resinas acrílicas foram classificadas pelo teste de incorporação do 3Htimidina como moderadamente citotóxicas. Da mesma forma, para o teste do MTT, não foi encontrada diferença significativa para a citotoxicidade entre os materiais (P>0.05). Quando a citotoxidade foi comparado com o grupo controle, todas as resinas foram classificadas entre não citotóxicas e discretamente citotóxicas pelo teste do MTT. Assim, conclui-se que a incorporação dos agentes de ligação cruzada, EGDMA e BDMA não influenciaram significativamente sobre a citotoxicidade observada. Não houve diferença... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to determine the cytotoxicity in vitro of two trials autopolymerizing reline systems made with higher concentration of cross-linking agents, EGDMA and BDMA compared to a commercial reline resin. Sample disks of the three hard reline acrylic resins were fabricated under aseptic conditions. The Fibroblast L929 cells were cultured in 96-well plates and incubated for 24 h in Eagle's medium. Eluates were prepared by placing three samples into a sterile glass vial with 9 mL of Eagle's medium and incubating at 37ºC for 24 h. The cytotoxic effect from the eluates was evaluated using the 3H-thymidine incorporation and MTT assays, which reflect DNA synthesis levels and cell metabolism, respectively. The data were statistically analyzed by using the one-way analysis of variance (P<.05). With the 3H-thymidine incorporation assay, no significant differences (P > .05) were found between the materials. The mean quantity of isotope incorporated into cellular DNA for all acrylic resins was statistically smaller than for the control. All acrylic resins were graded by the 3Hthymidine incorporation assay as moderate cytotoxic. Similarly, with the MTT assay, no significant difference in cytotoxicity was found between the materials (P > .05). When the cytotoxicity was compared with control group, all resins assay were between non cytotoxic and slight cytotoxic by the MTT. The incorporation of cross-linking agents, EGDMA and BDMA had no significant influence on the cytotoxicity observed. There was no cell viability difference between all materials in both assays. / Orientador: Eunice Teresinha Giampaolo / Coorientador: Iracilda Zeppone Carlos / Banca: Renata Cristina Silveira Rodrigues Ferracioli / Banca: Iracilda Zeppone Carlos / Mestre