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Objectives: This study aimed to evaluate the influence of different polymerisation methods of acrylic resin for ocular prostheses on the subcutaneous tissue inflammatory response of rats. Methods: The study was conducted at the Basic Sciences Department, Araçatuba Dental School, São Paulo State University (UNESP), Brazil, from 2016 to 2018. The samples were prepared by water bath (WB), microwave energy (MW) or autopolymerisation (AP) (n = 20 samples per group). The inflammatory response (cell count and immunohistochemical analysis of interleukin [IL]-1ß, IL-6, tumour necrosis factor [TNF]-α, IL-17 and macrophage inflammatory protein-3α) was analysed by the implantation of a sample from each group in the subcutaneous tissue of 20 Wistar rats and evaluated after seven, 15, 30 and 60 days. The quantitative and qualitative data were analysed using analysis of variance and Tukey tests (P <0.05) and visual comparison, respectively. Results: There was a moderate inflammatory infiltrate for the MW and AP groups and a light infiltrate for the WB group after seven days. The inflammatory infiltrate and the immunolabeling of tested targets decreased gradually during the 60-day period. The AP group had the highest immunolabeling of TNF-α (seven days), IL-1ß and IL-17 (at 15 and 30 days) and IL-6 (at 30 and 60 days). The WB and MW groups showed greater immunolabeling at 15 and 30 days, while the MW group also had high results at 60 days. Conclusion: Polymerisation by microwave energy and by chemical activation resulted in a higher inflammatory response.

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Article This study evaluated comparatively two configurations (powder and putty) of a composite biomaterial based on PLGA (Poly(lactide-co-glycolide)/nanoescale hydroxyapatite (ReOss®, Intra-Lock International) through microscopic morphology, in vitro cytotoxicity, biocompatibility and in vivo response as a bone substitute. SEM and EDS characterized the biomaterials before/after grafting. Cytocompatibility was assessed with murine pre-osteoblasts. Osteoconductivity and biocompatibility were evaluated in White New Zealand rabbits. Both configurations were implanted in the calvaria of eighteen animals in non-critical size defects, with blood clot as the control group. After 30, 60 and 90 days, the animals were euthanized and the fragments containing the biomaterials and controls were harvested. Bone blocks were embedded in paraffin (n=15) aiming at histological and histomorphometric analysis, and in resin (n=3) aiming at SEM and EDS. Before implantation, the putty configuration showed both a porous and a fibrous morphological phase. Powder revealed porous particles with variable granulometry. EDS showed calcium, carbon, and oxygen in putty configuration, while powder also showed phosphorus. After implantation EDS revealed calcium, carbon, and oxygen in both configurations. The materials were considered cytotoxic by the XTT test. Histological analysis showed new bone formation and no inflammatory reaction at implant sites. However, the histomorphometric analysis indicated that the amount of newly formed bone was not statistically different between experimental groups. Although both materials presented in vitro cytotoxicity, they were biocompatible and osteoconductive. The configuration of ReOss® affected morphological characteristics and the in vitro cytocompatibility but did not impact on the in vivo biological response, as measured by the present model.

Resumo Este estudo avaliou comparativamente duas configurações (pó e massa) de um biomaterial composto com base de PLGA (Poli(láctico-co-glicólico)/hidroxiapatita em nanoescala (ReOss®, Intra-Lock International) através da morfologia microscópica, citotoxicidade in vitro, biocompatibilidade e resposta in vivo como substituto ósseo. MEV e EDS caracterizaram os biomateriais antes/após o enxerto. A citocompatibilidade foi avaliada em pré-osteoblastos murinos. A osteocondutividade e a biocompatibilidade foram avaliadas em coelhos Branco da Nova Zelândia. Ambas as configurações foram implantadas na calvária de dezoito animais em defeitos não-críticos, com coágulo sanguíneo como grupo controle. Após 30, 60 e 90 dias, os animais foram eutanasiados e os fragmentos contendo os biomateriais e controles coletados. Blocos ósseos foram embebidos em parafina (n=15) destinados às análises histológica e histomorfométrica, e em resina (n=3) destinadas à MEV e EDS. Antes da implantação, a configuração massa mostrou ambas fases morfológicas porosa e fibrosa. O pó revelou partículas porosas com granulometria variável. EDS mostrou cálcio, carbono e oxigênio na configuração massa, enquanto o pó mostrou também fósforo. Após a implantação a EDS revelou cálcio, carbono e oxigênio em ambas configurações. Os materiais foram considerados citotóxicos pelo teste XTT. A análise histológica mostrou nova formação óssea e nenhuma reação inflamatória nos sítios de implante. Entretanto, a análise histomorfométrica indicou que a quantidade de osso neoformado não foi estatisticamente diferente entre os grupos experimentais. Embora ambos os materiais tenham apresentado citotoxicidade in vitro, foram biocompatíveis e osteocondutores. A configuração do ReOss® afetou as características morfológicas e a citocompatibilidade in vitro, porém não impactou a resposta biológica in vivo, como medido pelo presente modelo.

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OBJECTIVE: The aim of this study was to investigate the biocompatibility of methylene blue at different pH levels through the method of implantation in subcutaneous tissue. MATERIALS AND METHODS: Eighty-four sterilized polyethylene tubes were allocated in the subcutaneous tissue of 28 rats, each one receiving four tubes, set into four groups: group tube (G-T)-empty tube, fibrin group (G-F)-tube filled with fibrin sponge, group methylene blue pH 7 (G-MB/pH 7)-tube filled with fibrin sponge soaked by methylene blue (100 µg/ml) at pH 7.0, and group methylene blue pH 1 (G-MB/pH 1)-tube filled with fibrin sponge and soaked by methylene blue (100 µg/ml) at pH 1.0. After 7, 15, and 30 days, seven animals from each group were euthanized, and the tubes involved by the surrounding tissue were removed and fixed with 4% buffered formaldehyde solution. The collected pieces were processed and histological sections (4 µm) were stained with hematoxylin and eosin and analyzed by light microscopy. Scores were assigned to analysis of histopathologic parameters. The results were statistically analyzed by the Kruskal-Wallis test (p ≤ 0.05). RESULTS: At 7 and 30 days, the G-MB/pH 1 group showed no significant difference in the G-T control group, while G-MB/pH 7 had a significant increase on tissue reaction, also when compared to G-T. At 15 days, there was no statistical difference between the groups. CONCLUSION: Within the limits of this study, it is concluded that methylene blue at pH 1.0 provides better biocompatibility than at pH 7.0.

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O objetivo desse estudo foi avaliar a influência de diferentes ciclos e métodos de polimerização da resina acrílica (RA) branca de próteses oculares sobre a biocompatibilidade de células da conjuntiva humana e resposta inflamatória do tecido subcutâneo de ratos. Para isso, foram confeccionados corpos de prova em RA termopolimerizados em água aquecida (RNAA), por energia de microondas (RNTM) e quimicamente ativados (RNQA). Para a análise in vivo, a resposta inflamatória desses 3 grupos (n=20/grupo) foi avaliada no tecido subcutâneo de 20 ratos Wistar por 7, 15, 30 e 60 dias (d). Células inflamatórias foram contadas no tecido adjacente ao corpo de prova após coloração com hematoxilina e eosina. A análise imunohistoquímica foi realizada para a detecção de IL-1ß, IL-6, TNFα, IL-17 e CCL20. Para a análise in vitro, diferentes ciclos de polimerização para cada método citado foram avaliados, totalizando 11 grupos (n=8/grupo). Foram realizadas análises de grau de conversão (GC), MTT, Alamar Blue, ELISA, RT-PCR em tempo real e dupla marcação de Anexina V e iodeto de propídio. Dados quantitativos foram submetidos à Análise de Variância e ao teste de Tukey com significância de 5%. Os resultados qualitativos foram comparados visualmente. Na análise in vivo, houve infiltrado inflamatório moderado para os grupos RNTM e RNQA e leve para o grupo RNAA após 7 d. O infiltrado inflamatório e a imunomarcação dos alvos testados diminuiu gradativamente ao longo dos 60 d. O grupo RNTM exibiu mais células inflamatórias, com exceção do grupo RNAA, que apresentou mais eosinófilos e linfócitos após 15 d, e do grupo RNQA, onde foi observado mais macrófagos em 15 d e neutrófilos em 60 d. Os grupos RNAA e RNQA apresentaram maior imunomarcação de IL-1ß após 7 d. O grupo RNQA apresentou maior imunomarcação de IL-1ß (15 e 30 d), IL-6 (30 e 60 d), IL-17 (15 e 30 d) e TNF-α (7 d). Os grupos RNAA e RNTM apresentaram maior imunomarcação de TNF-α nos períodos de 15 e 30 d, enquanto o grupo RNTM, aos 60 d. Na análise in vitro, todos os grupos apresentaram proliferação celular maior que 75%. O ciclo longo de polimerização em microondas apresentou menor GC e percentual de proliferação celular no MTT e resultou em grande liberação de IL-2. No ensaio de Alamar Blue, esse grupo apresentou baixo percentual de proliferação celular, assim como o grupo que recebeu ciclo longo de polimerização em água aquecida e grupos submetidos à ativação química. Maior liberação de IL-6 foi observada nos grupos submetidos à ativação química e de IL-23 para o ciclo curto de polimerização em microondas. Maior expressão gênica de TGF ß1 ocorreu para o grupo que recebeu ciclo longo de polimerização em água aquecida seguido de 30 min de armazenamento em água. Maior expressão gênica de CASP9 ocorreu para o grupo ativado quimicamente sobre a bancada. Pode-se concluir que os métodos de polimerização por meio de energia de microondas (ciclos longo e curto) e por ativação química desencadearam uma resposta inflamatória mais intensa. Dentre os métodos de polimerização recomendados pelo fabricante, a polimerização em água aquecida apresentou resultados mais satisfatórios(AU)

The aim of this study was to evaluate the influence of different cycles and methods of white color acrylic resin (AR) for ocular prosthesis on the biocompatibility of human conjunctival cells and on the inflammatory response of rat subcutaneous tissue. For this, AR specimens were prepared in water bath (NRWB), by microwave energy (NRME), and chemically activated (ANR). For in vivo analysis, the inflammatory response of these 3 groups (n=20/group) was assessed in subcutaneous tissue of 20 Wistar rats at 7, 15, 30 and 60 days (d). Inflammatory cells were counted in the tissue adjacent to specimen after staining with hematoxylin and eosin. The immunohistochemical analysis was performed for the detection of IL-1ß, IL-6, TNFα, IL-17, and CCL20. For in vitro analysis, different cycles of polymerization for each method were evaluated, with a total of 11 groups (n=8/group). The degree of conversion (DC), MTT, ELISA, real-time RT-PCR and Annexin V and propidium iodide assays were performed. Quantitative data were submitted to Analysis of Variance and Tukey test with a 5% significance. Qualitative data were submitted to visual comparison. In in vivo analysis, there was a moderate inflammatory infiltrate for groups NRME and ANR, and a light infiltrate for the group NRWB after 7 d. The inflammatory infiltrate and the immunolabeling of tested targets decreased gradually during the 60 d. The group NRME exhibited the highest number of inflammatory cells, except for the group NRWB, which presented a higher number of eosinophils and lymphocytes after 15 d, and for the group ANR, where a higher number of macrophages and neutrophils were observed at 15 d and at 60 d, respectively. Groups NRWB and ANR showed higher IL-1ß immunolabeling after 7 d. The group ANR had the highest immunolabeling of IL-1ß (15 and 30 d), IL-6 (30 and 60 d), IL-17 (15 and 30 d), and TNF-α (7 d). Groups NRWB and NRME showed greater immunolabeling in the periods of 15 and 30 d, while the group NRME had also high results at 60 d. In in vitro analysis, all groups showed cell proliferation higher than 75%. The long cycle of polymerization using microwave energy resulted in lower DC and lower percentage of cell proliferation in the MTT assay and in large release of IL-2. In the Alamar Blue assay, this group had a low percentage of cell proliferation, as well as the group that received a long cycle of polymerization in water bath and groups submitted to chemical activation. A higher release of IL-6 was observed in groups submitted to chemical activation and of IL-23, for the short cycle of polymerization in microwave. Higher TGF ß1 gene expression occurred for the group that received long cycle of polymerization in water bath followed by 30 min of storage in water. Higher CASP 9 gene expression occurred for the chemically activated group on bench. It can be concluded that the polymerization by microwave energy (long and short cycles) and by chemical activation resulted in higher inflammatory response. Among methods recommended by the manufacturer, the water bath polymerization showed more satisfactory results(AU)

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CONTEXT: A novel root-filling material based on the incorporation of ultrafine alkaline bioactive glass particles (bioactive gutta-percha, [BGP]) was developed to work without sealer. AIM: In the present study, the objective was to verify the in vitro biological response to this material by assessing its cytocompatibility. MATERIALS AND METHODS: Prototypes of BGP were compared to conventional gutta-percha (GP), dense polystyrene beads as a negative control and fragments of latex as a positive control. Extracts of each material were prepared according to ISO 10993-5:2009, and human osteoblast-like cells in primary culture were exposed to all extracts for 24 h. Cell viability was assayed sequentially for three different parameters: mitochondrial activity, membrane integrity, and cell density. STATISTICAL ANALYSIS USED: Nonparametric analysis (using Kruskal-Wallis test combined with post hoc Dunn's test) was performed for comparison among groups, with significance established at 5%. RESULTS: BGP reduced mitochondrial activity to 62% of control, but presented no toxicity on membrane integrity and proliferation assays. BGP effect on metabolism was dose-dependent and reduced to acceptable levels with dilution. CONCLUSION: The novel GP material presented slight dose-dependent effects on cell metabolism but did not affect cell survival.

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OBJECTIVES: This study evaluated the release of ions and the cytotoxicity of acrylic resins incorporated with silver vanadate decorated with silver nanoparticles (AgVO3 ). BACKGROUND: The inhibition of the accumulation of microorganisms on the resins is critical in preventing diseases. However, the hypothesis is that the release of ions from the incorporation of AgVO3 may be important in biocompatibility. MATERIALS AND METHODS: Specimens of autopolymerising (AP) and heat-polymerising resin (HP) with AgVO3 were prepared and immersed in culture medium. The release of silver ions (Ag) and vanadium (V) was evaluated by mass spectrometry with inductively coupled plasma (ICP-MS) (n=9) and the cell viability of fibroblasts L929 by MTT (3-[4,5-dimethylthiazol- 2yl]-2,5-diphenyltetrazolium bromide) (n=12). The results were evaluated with analysis of variance (ANOVA), Tukey and Pearson correlation test (α=.05). RESULTS: The groups containing AgVO3 presented a difference in relation to the control (0%) regarding the release of Ag and V (P<.0001). All groups showed a reduction in L929 viability when compared with the cellular control (100%) (P<.0001). In comparison with the control resins for HP, a reduction in the metabolism of cells occurred starting at 2.5% and for AP at 5% (P<.0001). A positive correlation was found between the concentration of AgVO3 and the ion release, and a negative between the ion release and the cell viability. CONCLUSIONS: Significant numbers of Ag and V ions were released from resins with higher concentrations of AgVO3 , presenting cytotoxicity for cells, suggesting that the use of low concentrations is indicated to avoid risks to patients.

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The aim of this study was to evaluate the influence of pigment incorporation on the cytotoxicity of ocular prosthesis N1 color acrylic resin. Nine samples were manufactured by heat-polymerization in water bath and divided into 3 groups: acrylic resin without pigment incorporation (group R), acrylic resin with pigment incorporation (group RP), and acrylic pigment (group P). Eluates formed after 72h of sample immersion in medium were incubated with conjunctival cell line (Chang conjunctival cells) for 72h. The negative control group consisted in medium without samples (group C). The cytotoxic effect from the eluates was evaluated using MTT assay (cell proliferation), ELISA assay (quantification of IL1ß, IL6, TNF α and CCL3/MIP1α) and RT-PCR assay (mRNA expression of COL IV, TGF ß and MMP9). Data were submitted to ANOVA with Bonferroni post-tests (p<0.05). All groups were considered non-cytotoxic based on cell proliferation. However, resin with pigment incorporation showed significant IL6 quantity increase. Resin without pigment incorporation exhibited higher mRNA expression of COL IV, MMP9 and TGF ß, however it was also observed for the negative control group. The materials exhibited divergent biological behavior. Despite the pigment incorporation that resulted in an increase of IL6, no cytotoxicity was observed based on cell proliferation.

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ABSTRACT Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p<0.05) indicating greater biosorption. An increase in the RANKL/OPG ratio was observed in the CHA group on the 7th day. Conclusion CHA spheres were osteoconductive and presented earlier biosorption, inducing early increases in the levels of proteins involved in resorption.

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A prótese ocular é utilizada para a reabilitação estética e funcional da ausência ocular. O conhecimento da sua biocompatibilidade é importante para a utilização sem reações danosas aos usuários. O objetivo neste estudo foi avaliar a citotoxicidade de materiais utilizados na confecção de próteses oculares, por meio da análise da proliferação celular e da produção de citocinas pró-inflamatórias e de proteínas de matriz extracelular por células da conjuntiva humana. Inicialmente, foi analisada a influência de diferentes períodos de formação e de exposição dos extratos de resina acrílica branca (N1), termopolimerizada em água aquecida, sobre culturas de células da conjuntiva. Foram confeccionados 24 corpos de prova em resina, sendo 12 para cada período de exposição de células da conjuntiva aos extratos da resina testada (24 e 72 horas). Após a formação dos extratos por 24, 48 e 72 horas de imersão em meio de cultura e, 24 horas em água seguido de 24 horas de imersão em meio, os ensaios propostos foram realizados (n=3). Em seguida, foi avaliado o efeito citotóxico de diferentes métodos de polimerização de resina acrílica N1 em células da conjuntiva. Foram confeccionados 9 corpos de prova em resina (n=3), termopolimerizados em água aquecida, por energia de microondas ou ativados quimicamente, utilizados para a formação dos extratos dessas resinas. Os extratos foram obtidos após 72 horas de imersão dos corpos de prova em meio de cultura e, então, expostos às células da conjuntiva por 72 horas para a realização dos ensaios propostos. Adicionalmente, foi analisada a influência da presença do pigmento acrílico na confecção da prótese de resina acrílica N1, termopolimerizada em água aquecida. Foram confeccionados 9 corpos de prova (n=3): resina N1, resina N1 + pigmento e, pigmento, utilizados para a formação dos extratos desses materiais. Os extratos formaram-se por 72 horas de imersão dos corpos de prova em meio de cultura e, então, foram expostos às células da...

Ocular prosthesis is a treatment option for esthetical and functional rehabilitation of ocular absence. The knowledge of ocular prosthesis material’s biocompatibility is important to ensure a safe use in patients. The aim of this study was to evaluate the cytotoxic effect of ocular prosthesis materials, through the analysis of the cell proliferation, and the production of proinflammatory cytokines and extracellular matrix proteins by a human conjunctival cell line. Initially, the influence of different preparation and exposition periods of eluates from heat-polymerized ocular prosthesis N1 color acrylic resin in human conjunctival cell line was evaluated. A total of 24 acrylic resin samples were manufactured and divided into 2 groups, according to the eluate exposition period to conjunctival cell line (24 and 72 hours). Eluates corresponding to 24, 48 and 72 hours of resin sample immersion in medium and, 24 hours of resin sample immersion in water followed by 24 hours of immersion in medium, were prepared (n=3) for the proposed tests. Then, the cytotoxic effect of different polymerization methods of ocular prosthesis N1 color acrylic resin was analyzed. A total of 9 acrylic resin samples were manufactured (n=3), according to the polymerization method: heat-polymerization in water bath, polymerization by microwave energy and auto-polymerization. Eluates corresponding to 72 hours of resin sample immersion in medium were prepared for proposed tests and exposed to conjunctival cell line for 72 hours. Additionally, the influence of pigment incorporation on the cytotoxicity of heat-polymerized ocular prosthesis N1 color acrylic resin was evaluated. A total of 9 samples were manufactured (n=3): N1 color acrylic resin without pigment incorporation, N1 color acrylic resin with pigment incorporation, and acrylic pigment. Eluates corresponding to 72 hours of sample immersion in medium were prepared and exposed to conjunctival cell line for 72 hours. The cytotoxic effect...

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O presente estudo in vitro objetivou avaliar a longo prazo o potencial antimicrobiano residual e a citotoxicidade de soluções químicas de limpeza de prótese quando incorporadas à resina acrílica termopolimerizável após sucessivos ciclos de imersão noturna diária. Discos (10mm x 1mm) de resina acrílica termopolimerizável para base de prótese (Lucitone 550) foram submetidos a três ciclos diários de desinfecção (8h/cada) em hipoclorito de sódio a 1% (NaClO), digluconato de clorexidina a 2% (CLX) ou água destilada (controle) durante 91 (T91) ou 183 dias (T183), simulando o período de 9 meses ou 1,5 ano de imersão noturna diária realizada pelo paciente. Inicialmente, foi utilizado o método de concentração inibitória mínima em caldo para determinar o possível efeito residual (incorporação) das soluções à resina acrílica. Metade dos discos imersos em cada agente de limpeza em um dos tempos de imersão (n=5) foi inoculada (1x107cels/mL) com um dos patógenos associados à estomatite protética: Candida albicans (Ca) e Staphylococcus aureus (Sa). Os discos foram incubados a 37oC para análise em espectrofotômetro após 24h, 7 e 14 dias. Os valores de absorbância foram convertidos em porcentagens de inibição microbiana. Confirmada a ação antimicrobiana residual dos agentes de limpeza incorporados à resina acrílica, foi então analisada sua citotoxicidade in vitro sobre fibroblastos gengivais humanos (L929). Os efeitos citotóxicos foram avaliados por meio do ensaio colorimétrico MTT [brometo de 3-(4,5-dimetiltiazol-2-yl)-2,5-difeniltetrazólio] para a determinação da viabilidade celular, após as células serem expostas por 24h às amostras de cada condição experimentais (n=18) previamente imersas em uma das soluções por um dos períodos avaliados (T91 ou T183). A citotoxicidade foi determinada com base na atividade mitocondrial em relação a corpos de prova não submetidos à imersão nas soluções testadas. Os resultados do ensaio do MTT foram analisados estatisticamente por ANOVA...

This in vitro study aimed to evaluate the long-term residual antimicrobial activity and cytotoxicity of chemical denture cleansers incorporated into a heat-polymerized acrylic resin after successive cycles of daily overnight soaking. Discs (10mm x 1mm) were prepared from heat-polymerized acrylic resin (Lucitone 550) and submitted to three daily immersion (8h/each) in 1% sodium hypochlorite (NaClO), chlorhexidine digluconate 2% (CHX) or distilled water (control) for 91 days (T91) or 183 days (T183), simulating the period of 9 months or 1.5 year of nocturnal immersion performed by the patient. Initially, the method of minimum inhibitory concentration in broth was used to determine the possible residual effect (incorporation) of the acrylic resin solution. Half of the disks immersed in each cleaning agent for one of the period immersion (n=5) was inoculated (1x107cells/mL) with pathogens associated with denture stomatitis: Candida albicans (Ca) or Staphylococcys aureus (Sa). The disks were incubated at 37oC for analysis in a spectrophotometer after 24h, 7 and 14 days. The absorbance values were expressed as percentages of microbial inhibition. Confirmed the residual antimicrobial action of cleaning agents incorporated into the acrylic resin, its cytotoxicity was analyzed in vitro on human gingival fibroblasts (L929). Cytotoxic effects were evaluated by the colorimetric assay MTT [3- (4,5- dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium bromide] to determine cellular viability after the cells were exposed for 24h to the samples of each experimental condition (n=18) previously immersed in one of the solutions for the evaluation periods (T91 or T183). Cytotoxicity was determined based on mitochondrial activity compared to the specimens not subjected to immersion in the solutions. The MTT assay results were 1-way ANOVA followed by Tukey's HSD post-hoc test (a=0.05). For the periods T91 and T183, no microbial inhibition was observed with immersion in water...

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A prótese ocular é utilizada para a reabilitação estética e funcional da ausência ocular. O conhecimento da sua biocompatibilidade é importante para a utilização sem reações danosas aos usuários. O objetivo neste estudo foi avaliar a citotoxicidade de materiais utilizados na confecção de próteses oculares, por meio da análise da proliferação celular e da produção de citocinas pró-inflamatórias e de proteínas de matriz extracelular por células da conjuntiva humana. Inicialmente, foi analisada a influência de diferentes períodos de formação e de exposição dos extratos de resina acrílica branca (N1), termopolimerizada em água aquecida, sobre culturas de células da conjuntiva. Foram confeccionados 24 corpos de prova em resina, sendo 12 para cada período de exposição de células da conjuntiva aos extratos da resina testada (24 e 72 horas). Após a formação dos extratos por 24, 48 e 72 horas de imersão em meio de cultura e, 24 horas em água seguido de 24 horas de imersão em meio, os ensaios propostos foram realizados (n=3). Em seguida, foi avaliado o efeito citotóxico de diferentes métodos de polimerização de resina acrílica N1 em células da conjuntiva. Foram confeccionados 9 corpos de prova em resina (n=3), termopolimerizados em água aquecida, por energia de microondas ou ativados quimicamente, utilizados para a formação dos extratos dessas resinas. Os extratos foram obtidos após 72 horas de imersão dos corpos de prova em meio de cultura e, então, expostos às células da conjuntiva por 72 horas para a realização dos ensaios propostos. Adicionalmente, foi analisada a influência da presença do pigmento acrílico na confecção da prótese de resina acrílica N1, termopolimerizada em água aquecida. Foram confeccionados 9 corpos de prova (n=3): resina N1, resina N1 + pigmento e, pigmento, utilizados para a formação dos extratos desses materiais. Os extratos formaram-se por 72 horas de imersão dos corpos de prova em meio de cultura e, então, foram expostos às células da...

Ocular prosthesis is a treatment option for esthetical and functional rehabilitation of ocular absence. The knowledge of ocular prosthesis material’s biocompatibility is important to ensure a safe use in patients. The aim of this study was to evaluate the cytotoxic effect of ocular prosthesis materials, through the analysis of the cell proliferation, and the production of proinflammatory cytokines and extracellular matrix proteins by a human conjunctival cell line. Initially, the influence of different preparation and exposition periods of eluates from heat-polymerized ocular prosthesis N1 color acrylic resin in human conjunctival cell line was evaluated. A total of 24 acrylic resin samples were manufactured and divided into 2 groups, according to the eluate exposition period to conjunctival cell line (24 and 72 hours). Eluates corresponding to 24, 48 and 72 hours of resin sample immersion in medium and, 24 hours of resin sample immersion in water followed by 24 hours of immersion in medium, were prepared (n=3) for the proposed tests. Then, the cytotoxic effect of different polymerization methods of ocular prosthesis N1 color acrylic resin was analyzed. A total of 9 acrylic resin samples were manufactured (n=3), according to the polymerization method: heat-polymerization in water bath, polymerization by microwave energy and auto-polymerization. Eluates corresponding to 72 hours of resin sample immersion in medium were prepared for proposed tests and exposed to conjunctival cell line for 72 hours. Additionally, the influence of pigment incorporation on the cytotoxicity of heat-polymerized ocular prosthesis N1 color acrylic resin was evaluated. A total of 9 samples were manufactured (n=3): N1 color acrylic resin without pigment incorporation, N1 color acrylic resin with pigment incorporation, and acrylic pigment. Eluates corresponding to 72 hours of sample immersion in medium were prepared and exposed to conjunctival cell line for 72 hours. The cytotoxic effect...

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Biocompatibilidade é a capacidade de um material exercer funções específicas quando aplicado em contato com tecidos vivos de determinado hospedeiro, sem, contudo, causar danos ou prejuízo ao mesmo. Este trabalho objetivou determinar a biocompatibilidade in vivo e in vitro do extrato hidroalcoólico do Cissus sicyoides L - Vitaceae. Foram utilizados 30 ratos (Rattus novergicus albinus wistar), com idade entre 45 e 90 dias e pesando entre 170 e 260 g. Os animais foram divididos em 3 grupos (A1, A2 e A3) de 6 animais cada para o teste in vivo, os quais foram sacrificados com 2, 4 e 6 dias, respectivamente. Para o teste in vitro, foram utilizados 12 animais para obtenção do índice de aderência e da capacidade fagocítica dos macrófagos de ratos do grupo controle e do grupo experimental. Nos resultados encontrados no teste in vivo, conclui-se que o extrato apresentou-se biocompatível, visto que não provocou alterações significativas no tecido. Já no teste in vitro, o mesmo não se apresentou biocompatível, pois o extrato puro apresentou índice de aderência baixo (7,1) e taxa de fagocitose elevada (35,7), indicando diferença significante quando comparado ao controle. Porém, quando diluído, o extrato se mostrou inócuo, devido ao aumento dos valores do índice de aderência nas concentrações de 1/10 (61,4) e 1/100 (74,3) nos ensaios, as quais não apresentaram diferença significante quando comparadas ao controle. Após a análise dos dados, concluiu-se que a solução diluída do extrato hidroalcoólico do Cissus sicyoides L. não causa danos ou prejuízos. Entretanto, como nem todos os efeitos farmacológicos foram testados no presente trabalho, não se pode inferir automaticamente que ele é biocompatível em todos os casos.

Biocompatibility is the ability of a material to perform specifictasks when applied to living tissues without causing damage or injuries to it. Thus, this study aimed at determining the in vivo and in vitro biocompatibility of Cissus sicyoides L. - Vitaceae hydroalcoholic extracts. A total of 30 rats (Rattus norvegicus Albinus Wistar), with ages ranging from 45 to 90 days and weighing between 170 and 260g were used. The animals were divided into 3 groups (A1, A2 and A3) with 6 animals each, for the in vivo test, which were sacrificed after 2, 4 and 6 days, respectively. For in vitro test, 12 animals were used to obtain the index of adherence and phagocytic ability of macrophages of rats from the control and the experimental groups. In results found for the in vivo test, it was concluded that the extract was biocompatible, whereas no significant changes were observed in the tissue. As to the in vitro test, the extract was not biocompatible, since the pure extract showed a low rate of adherence (7.1) and a high rate of phagocytosis (35.7), indicating a significant difference when compared to the control group. However, when diluted, the extract was shown to be harmless, due to an increase in the values of the adherence index at the following concentrations : 1/10 (61.4) and 1/100 (74.3) in the tests, which showed no significant differences when compared to the control group. After analyzing the data, it was concluded that since the infusion of the plant is a kind of dilution, its use does not cause any harm to the body. A new study is necessary at the moment to possibily demonstrate its effects on the long term.

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OBJECTIVES: This study investigated cellular attachment to 6 root-end filling materials as a measure of the biocompatibility of the materials. MATERIAL AND METHODS: Class I retrograde cavities were prepared in root slices and these cavities were filled with the test materials, and incubated with Balb/C 3T3 fibroblasts for 24 h. Root slices with the cavities left empty served as the controls. The root slices were then processed for scanning electron microscopy, and were viewed to assess the quality of cellular attachment by observing the shape of cells, spread, and membrane outline. RESULTS: The best cellular attachment was observed at MTA and Geristore surfaces: cells exhibited characteristic elongated fibroblastic morphology, with projections of lamellipodia, filopodia, blebs, and microvilli from their surfaces, reflecting good attachment to the material. Fibroblasts attached poorly to the surfaces of IRM, Super EBA, KetacFil and Retroplast. Furthermore, the cells did not attach well to the tooth structure next to IRM and Super EBA. CONCLUSIONS: The present study demonstrated a variation in cellular attachment to different root-end filling materials with the best cellular attachment to the surfaces of MTA and Geristore. IRM and Super EBA, Ketac Fil and Retroplast rendered poor attachment.

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OBJECTIVE: The physicochemical properties of hydroxyapatite (HA) granules were observed to affect the biological behavior of graft materials. The aim of this work was to analyze the tissue response of two HA granules with different crystallinity and Ca/P ratio in vivo. MATERIAL AND METHODS: The HA granules were produced in the Biomaterials Laboratory (COPPE/UFRJ). The testing materials were HA granules presenting a Ca/P molar ratio of 1.60 and 28 percent crystallinity (HA-1), and a Ca/P molar ratio of 1.67 and 70 percent crystallinity (HA-2). Both HAs were implanted into a critical-size calvaria rat defects. RESULTS: To note, in the control group, the bone defects were filled with blood clot only. Descriptive and histomorphometric analyses after 1, 3, and 6 months postoperatively showed mild inflammatory infiltrate, mainly comprising macrophage-like and multinucleated giant cells, and an increase in the volume density of the fibrous tissues (p<0.05), which was in contrast to the similar volume density of the newly formed bone and biomaterials in relation to the control group. CONCLUSION: Thus, we concluded that HA-1 and HA-2 are biocompatible and non-degradable, and that crystallinity does not affect bone repair of critical size defects.

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OBJECTIVE: The aim of this study was to investigate the effects of mineral trioxide aggregate (MTA), Sealapex, and a combination of Sealapex and MTA (Sealapex Plus) on the reaction of subcutaneous connective tissue of rats, and on cell viability and cytokine production in mouse fibroblasts. MATERIAL AND METHODS: The tissue reaction was carried out with dentin tubes containing the materials implanted in the dorsal connective tissue of rats. The histological analysis was performed after 7 and 30 days. Millipore culture plate inserts with polyethylene tubes filled with materials were placed into 24-well cell culture plates with mouse fibroblasts to evaluate the cell viability by MTT assay. ELISA assays were also performed after 24 h of exposure of the mouse fibroblasts to set material disks. RESULTS: Histopathologic examination showed Von Kossa-positive granules that were birefringent to polarized light for all the studied materials at the tube openings. No material inhibited the cell viability in the in vitro test. It was detected IL-6 production in all root-end filling materials. MTA and Sealapex Plus induced a slight raise of mean levels of IL-1β. CONCLUSIONS: The results suggest that Sealapex Plus is biocompatible and stimulates the mineralization of the tissue.

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The aim of this study was to evaluate the subcutaneous biocompatibility of: Epiphany, AH Plus, Pulp Canal Sealer and Sealapex root canal sealers. Sixty rats were randomly assigned to 4 groups, according to the sealer. Polyethylene tubes containing the tested materials were inserted into the connective tissue. The implants were removed after 7, 15 and 30 days, and the tissue samples were processed, stained and examined by light microscopy. The descriptive analysis considered: thickness of the fibrous capsule, severity of the inflammatory reaction, and presence of giant cells. After 7 days, all sealers induced moderate to severe inflammatory reaction. After 15 days, Epiphany and AH Plus sealers showed a moderate inflammatory reaction, while Pulp Canal Sealer and Sealapex induced severe and mild inflammatory reactions, respectively. After 30 days, mild inflammatory reactions were observed for Epiphany, Sealapex and AH Plus. Sealapex induced the lowest inflammatory response at all evaluation periods, and only Pulp Canal Sealer did not show a decreased in the inflammatory reaction over time.

O objetivo deste estudo foi avaliar a biocompatibilidade subcutânea de cimentos endodônticos radiculares: Epiphany, AH Plus, Pulp Canal Sealer e Sealapex. Sessenta ratos foram divididos aleatoriamente em 4 grupos, de acordo com o cimento. Tubos de polietileno contendo os materiais testados foram inseridos no tecido conjuntivo. Os implantes foram removidos após 7, 15 e 30 dias, e as amostras de tecido foram processadas, coradas e examinadas por microscopia de luz. A análise descritiva considerou: espessura da cápsula fibrosa, severidade da reação inflamatória e presença de células gigantes. Após 7 dias, todos os cimentos induziram moderada e severa reação inflamatória. Após 15 dias, os cimentos Epiphany e AH Plus apresentaram uma reação inflamatória moderada, enquanto Pulp Canal Sealer e Sealapex induziram severa e leve reações inflamatórias, respectivamente. Após 30 dias, leve reação inflamatória foi observada para o Epiphany, Sealapex e AH Plus. Sealapex induziu a menor resposta inflamatória em todos os períodos de avaliação, e somente Pulp Canal Sealer não apresentou uma diminuição da reação inflamatória ao longo do tempo.

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ABSTRACT OBJECTIVE: The objective of the present study was to verify the hypothesis that no difference in biocompatibility exists between different orthodontic adhesives. MATERIAL AND METHODS: Thirty male Wistar rats were used in this study and divided into five groups (n=6): Group 1 (control, distilled water), Group 2 (Concise), Group 3 (Xeno III), Group 4 (Transbond XT), and Group 5 (Transbond plus Self-Etching Primer). Two cavities were performed in the subcutaneous dorsum of each animal to place a polyvinyl sponge soaked with 2 drops of the respective adhesive in each surgical loci. Two animals of each group were sacrificed after 7, 15, and 30 days, and their tissues were analyzed by using an optical microscope. RESULTS: At day 7, Groups 3 (Transbond XT) and 4 (Xeno III) showed intense mono- and polymorphonuclear inflammatory infiltrate with no differences between them, whereas Groups 1 (control) and 2 (Concise) showed moderate mononuclear inflammatory infiltrate. At day 15, severe inflammation was observed in Group 3 (Transbond XT) compared to other groups. At day 30, the same group showed a more expressive mononuclear inflammatory infiltrate compared to other groups. CONCLUSION: Among the orthodontic adhesive analyzed, it may be concluded that Transbond XT exhibited the worst biocompatibility. However, one cannot interpret the specificity of the data generated in vivo animal models as a human response.

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