Abstract The present study evaluated the effect of the taper angle of different internal conical connection implants and cyclic loading on the implant-abutment bacterial seal. A total of 96 implant-abutment sets were divided into eight groups. Four groups of different taper degrees with cyclic mechanical loading of 500,000 cycles per sample, with a 120-N load at 2 Hz before analysis [16DC (16-degree, cycled), 11.5DC (11.5-degree, cycled), 3DC (3- degree, cycled) and 4DC (4- degree, cycled)] were compared to four control groups without cyclic loading [16D (16-degree), 11.5D (11.5-degree), 3D (3-degree), and 4D (4-degree)]. Microbiological analysis was performed by immersing all samples in a suspension containing Escherichia coli and incubating them at 37°C. After 14 days, the presence of bacterial seals was evaluated. Fisher-Freeman-Halton exact tests and binomial tests were performed (5% significance level). The groups showed significant differences in bacterial seal, and mechanical load cycling improved the bacterial seal in the 3DC group. In all other groups, no significant differences in bacterial seal were found between cycled and uncycled samples. To conclude, the internal conical connection with a 3-degree taper angle showed better results than the other connection with different angles when subjected to load cycling. However, none of the angles tested were fully effective in sealing the implant-abutment interface.

Resumo Este estudo avaliou a centralização da região de interesse (ROI) na aquisição das imagens de TCFC, quando a função scout-view (SV) posicionável livremente é aplicada. Adicionalmente, a dosimetria das imagens adquiridas foi avaliada isoladamente na presença da função SV, bem como após aquisição de imagem tomográfica completa em dois diferentes campos de visão (FOV) (50x50 e 78x150mm). Um dispositivo de três localizações foi criado para acomodar os dosímetros e os espécimes, na localização direita, central e esquerda, durante a aquisição das imagens. Para avaliação da dose, dosímetros termoluminescentes foram irradiados dentro dos campos de visão e analisados em leitor portátil. Para avaliação da ROI, três espécimes de guta percha foram colocados no mesmo aparelho e as tomografias foram adquiridas (CBCT OP 300 Maxio, 90kV, 13mA, 85 μm tamanho de voxel, FOV de 50X50mm), com e sem a SV, em três posições (3-9, 1-7 e 5-11 horas), simulando diferentes regiões da boca. Foram realizadas duas avaliações de imagem, uma objetiva e outra subjetiva. Houve um leve aumento percentual (1,36% para 1,40%) da dose de radiação com o uso de SV. As distâncias foram significativamente maiores nas imagens adquiridas sem SV (p < 0,05). Todas as imagens obtidas com SV foram classificadas como sendo do centro do FOV. Em conclusão, os resultados do presente estudo demonstraram que a função scout view é eficaz para centralizar a ROI no FOV, aumentando a precisão do escaneamento e evitando repetições devido a erros de posicionamento.

Abstract This study evaluated the centralization of the region of interest (ROI) in acquisition of the CBCT images, when the freely positionable scout-view (SV) function is applied. Additionally, the dosimetry of the acquired images was assessed in the SV function alone as well as in complete tomographic image in two different fields of view (FOV) (50x50 and 78x150mm). A three-location device was created to accommodate the dosimeters and the specimens, in the right, middle and left location during image acquisition. For dose assessment, thermoluminescent dosimeters were irradiated within the FOV and analyzed in a portable reader. For ROI evaluation, three specimens of gutta-percha stick were placed on the same device and the CT scans were acquired (CBCT OP 300 Maxio device, 90kV, 13mA, 85 µm voxel size, FOV of 50X50mm), with and without the SV, in three positions (3-9, 1-7 and 5-11 o’clock), simulating different regions of the mouth. Two image evaluations were performed, an objective and subjective. There was a slight percentage increase (1.36% to 1.40%) of the radiation dose with the use of SV. The distances were significantly greater in the images acquired without SV (p < 0.05). Every image obtained with SV was classified as being at the FOV’s center. In conclusion, the results demonstrated that SVs function is effective to centralize the ROI in the FOV, increasing the scan precision and avoiding repetitions due to positioning errors.

Abstract Associated with the use of removable prostheses, the development of candidiasis, called prosthetic stomatitis, is frequently observed. In view of the application of silver nanoparticles (AgNP) in dentistry that may offer antimicrobial effect, the aim of this study was to evaluate the effect of adding AgNP with different concentrations during thermopolymerization or immersion of acrylic in this substance in the properties antifungal, mechanical and cytotoxic. The groups were divided: addition of 1% silver nanoparticle solution (G1), addition of 2.5% silver nanoparticle solution (G2), addition of 5% silver nanoparticle solution (G3), immersed for 10 min in aqueous silver nanoparticle solution (G4), immersed for 24 hours in aqueous silver nanoparticle solution (G5). In the cytotoxicity assay, at all evaluation times, all groups showed cytotoxic effect (p <0.05) when compared to the control group (CG). For the microbiological assay, C. albicans reduction was observed only for G4 and G5 when compared to CG (p <0.05). The lowest resistance values were observed in the group with 5% silver nanoparticle (G3) incorporation (p <0.05). It was concluded that the thermopolymerized acrylic resin immersed in AgNP, G4 and G5 promoted microbiological reduction, cytotoxicity increase and flexural strength decrease at 5% concentration.

Abstract This in vitro study evaluated the impact of TiO2 nanotubes (n-TiO2) incorporated into glass ionomer cement (GIC) on Streptococcus mutans (S. mutans) characteristics at cellular and molecular levels. n-TiO2, synthesized by the alkaline method (20 nm in size), was added to Ketac Molar EasyMix® at 0%, 3%, 5%, and 7% by weight. S. mutans strains were cultured on GIC disks with addition or not of n-TiO2 for 1, 3, and 7 days and the following parameters were assessed: inhibition halo (mm) (n=3/group); cell viability (live/dead) (n=5/group); cell morphology (SEM) (n=3/group); and gene expression by real-time PCR (vicR, covR, gtfB, gtfC, and gtfD) (n=6/group). The data were analyzed by the Kruskal-Wallis test, repeated-measures ANOVA or two-way ANOVA, and Tukey’s and Dunn’s post-hoc tests (α=0.05). The agar diffusion test showed a higher antibacterial property for 5% n-TiO2 compared with 3% and 7% (p<0.05) with no effect of time (1, 3, and 7 days). The cell number was significantly affected by all n-TiO2 groups, while viability was mostly affected by 3% and 5% n-TiO2, which also affected cell morphology and organization. Real-time PCR demonstrated that n-TiO2 reduced the expression of covR when compared with GIC with no n-TiO2 (p<0.05), with no effect of time, except for 3% n-TiO2 on vicR expression. Within-group and between-group analyses revealed n-TiO2 did not affect mRNA levels of gtfB, gtfC, and gtfD (p>0.05). Incorporation of n-TiO2 at 3% and 5% potentially affected S. mutans viability and the expression of key genes for bacterial survival and growth, improving the anticariogenic properties of GIC.

Abstract Bacterial colonization plays a key role on the pathogenesis of peri-implantitis and may be influenced by titanium surface topography. The aim of this in vitro study was to evaluate the influence of titanium topography after fluoride ions deposition in the bacterial colonization. Machined (M), double acid-etched (DE) and double acid-etched surface with fluoride ions deposition (Nano F-) were analyzed by scanning electron microscopy, contact angle and roughness (Ra). Streptococcus mutans viability was quantified by Live/Dead Baclight bacterial viability kit. The mean Ra/contact angle values were 0.20 μm/69.13°, 0.53 μm /92.82° and 0.56 μm/94.33° for M, DE and Nano F-, respectively. M surface presented significantly lower live bacterial counts when compared to the Nano F- surface (p=0.007). The dead bacteria count was higher on the Nano F- surface (p=0.001) than on the M and DE surfaces. Crystalline deposition of fluoride ions (Nano F-) promoted an increase in dead bacteria on the tested titanium surface.

Resumo Apesar de a periodontite ser uma das doenças infecto inflamatórias humanas mais comuns, os mecanismos que conduzem à imunopatologia não estão bem definidos. Inúmeras moléculas induzem atividade inflamatória que levam à perda óssea. Para que haja a reabsorção óssea, células monocíticas são ativadas e se transformam em osteoclastos. As moléculas TACE (Enzima conversora de TNF-α) e DC-STAMP (Proteína transmembrana específica de célula dendrítica) parecem atuar no processo de reabsorção óssea uma vez que a TACE induz a liberação de sRANKL (ativador do receptor do fator nuclear kappa-β ligante solúvel), enquanto a DC-STAMP é um fator chave na indução dos osteoclastos. Diante disso, o presente estudo avaliou a expressão gênica das moléculas TACE e DC-STAMP em pacientes com e sem periodontite uma vez que o papel destas moléculas no curso do desenvolvimento da periodontite ainda é pouco explorado. Foram selecionados 20 indivíduos, sendo 10 com saúde periodontal e com indicação para remoção de tecido gengival por motivos estéticos e 10 pacientes com periodontite. As análises da expressão das moléculas no tecido gengival foram realizadas por meio de western blotting. Os níveis proteicos tanto de TACE quanto de DC-STAMP, foram maiores nos tecidos do grupo com periodontite em comparação aos do grupo controle (p<0.05; Student' t-test). Portanto, os dados demonstram que a expressão protéica das moléculas TACE e DC-STAMP estão elevados em pacientes com periodontite, favorecendo a progressão da reabsorção óssea nesta patologia.

Abstract Although periodontitis is one of the commonest infectious inflammatory diseases in humans, the mechanisms involved with its immunopathology remain ill understood. Numerous molecules may induce inflammation and lead to bone resorption, secondary to activation of monocytes into osteoclasts. TACE (TNF-α converting enzyme) and DC-STAMP (dendritic cell-specific transmembrane protein) appear to play a role on bone resorption since TACE induces the release of sRANKL (soluble receptor activator of nuclear factor kappa-β ligand) whereas DC-STAMP is a key factor in osteoclast induction. The present study evaluated the levels of TACE and DC-STAMP in patients with and without periodontitis. Twenty individuals were selected: 10 periodontally healthy participants undergoing gingivectomy for esthetic reasons and 10 diagnosed with periodontitis. Protein levels of such molecules in gingival tissue were established using Western blotting. Protein levels of both TACE and DC-STAMP were higher in the periodontitis group than in the control group (p<0.05; Student t-test). In conclusion, TACE and DC-STAMP protein levels are elevated in patients with periodontitis, favoring progression of bone resorption.

Abstract The possible role of B-cell growth and differentiation-related cytokines on the pathogenesis of diabetes-related periodontitis has not been addressed so far. The aim of this study was to evaluate the effects of diabetes mellitus (DM) on the gene expression of proliferation-inducing ligand (APRIL) and B-lymphocyte stimulator (BLyS), two major cytokines associated to survival, differentiation and maturation of B cells in biopsies from gingival tissue with periodontitis. Gingival biopsies were obtained from subjects with periodontitis (n = 17), with periodontitis and DM (n = 19) as well as from periodontally and systemically healthy controls (n = 10). Gene expressions for APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were evaluated using qPCR. The expressions APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were all higher in both periodontitis groups when compared to the control group (p < 0.05). Furthermore, the expressions of BLyS, TRAP and RANKL were significantly higher in the subjects with periodontitis and DM when compared to those with periodontitis alone (p < 0.05). The mRNA levels of BLyS correlated positively with RANKL in the subjects with periodontitis and DM (p < 0.05). BLyS is overexpressed in periodontitis tissues of subjects with type 2 DM, suggesting a possible role of this cytokine on the pathogenesis DM-related periodontitis.

RESUMO Objetivos: este estudo teve como objetivo realizar uma avaliação histológica de um mini-implante para ancoragem em Ortodontia. Avaliou-se, também, a carga de cisalhamento e o padrão de fratura imediatamente e após 30 e 60 dias da sua inserção, com ou sem o uso do adesivo N-butil-2-cianoacrilato. Métodos: noventa e seis mini-implantes (Arrow, Peclab, Brasil) foram instalados na tíbia de nove coelhos machos, com ou sem adesivo (Vetbond™, 3M, EUA). A avaliação histológica foi realizada com uso de microscópico de luz óptica. Realizou-se o teste de resistência ao cisalhamento, seguido pela análise da fratura, por meio de inspeção visual. Resultados: um contato íntimo entre o novo osso formado e o dispositivo foi evidenciado no grupo sem adesivo, enquanto espaços foram encontrados no grupo com adesivo. O teste de Tukey mostrou valores semelhantes em ambos os grupos no tempo imediato (20,70 N sem adesivo e 24,69 N com adesivo), e valores maiores para o grupo sem adesivo após 30 e 60 dias (43,98 N e 78,55 N, respectivamente). Os valores para o grupo com adesivo foram semelhantes para os tempos imediato (24,69 N), 30 dias (18,23 N) e 60 dias (31,98 N). As fraturas foram adesivas para ambos os grupos, no tempo imediato. As fraturas foram coesivas no osso para os grupos sem adesivo, após 30 e 60 dias. Conclusões: os mini-implantes mostraram um contato íntimo com o osso e requereram alta carga de cisalhamento para sua remoção após 30 e 60 dias nos grupos sem adesivo. Estudos adicionais são necessários para avaliar um método para remoção do dispositivo ortodôntico sem fratura coesiva no osso.

ABSTRACT Objective: The objective of the present study was to perform a histological evaluation of a titanium mini-implant for orthodontic anchorage. Shear strength and fracture patterns that occurred immediately, 30 and 60 days after insertion with or without N-2-butyl-cyanoacrylate adhesive were evaluated. Methods: Ninety-six mini-implants (Arrow, Peclab, Brazil) were placed in the tibia of 9 male rabbits, with or without an adhesive (Vetbond™, 3M, USA). Histological evaluation was done by optical light microscope. Shear strength testing was performed, followed by fracture analysis with visual inspection. Results: Close contact between the newly formed bone and the device was evidenced in the group without adhesive, whereas gaps in the group with adhesive were found. Tukey test showed similar values in both groups at the immediate time point (20.70 N without adhesive and 24.69 N with adhesive), and higher values for the non-adhesive group, after 30 and 60 days (43.98 N and 78.55 N, respectively). The values for the adhesive group were similar for the immediate time point (24.69 N), 30 days (18.23 N) and 60 days (31.98 N). The fractures were adhesive for both groups at the immediate time point. The fractures were cohesive in bone for the non-adhesive group after 30 and 60 days. Conclusions: The mini-implants showed close bone contact and required higher shear strength for removal at 30 and 60 days for the non-adhesive group. Further studies are needed to assess the proper way to remove the orthodontic anchorage without cohesive fractures in bone.

RESUMO Objetivo: O objetivo desta revisão sistemática foi avaliar os desfechos do tratamento dos defeitos peri-implantares, por meio da técnica da Regeneração Óssea Guiada. Métodos: Uma pesquisa bibliográfica, baseada na metodologia PICO, foi realizada nas bases de dados eletrônica PubMed/Medline, SciELO, Lilacs periódicos Capes e Cochrane Library. Foram incluídos estudos que utilizaram matriz mineral bovina, associado a uma membrana de colágeno para o tratamento da peri-implantite por Regeneração Óssea Guiada. Resultados: De 1.163 estudos, 10 foram incluídos nesta revisão, após aplicação dos critérios de avaliação. Um total de 269 implantes foram tratados em 260 pacientes. O período de acompanhamento variou de 6 a 48 meses. Os estudos avaliados reportaram redução média da profundidade de sondagem, ganho de inserção clínica e preenchimento ósseo do defeito. Devido à heterogeneidade dos estudos não foi possível realizar metanálise. Conclusão: O tratamento das lesões peri-implantares, com a técnica da Regeneração Óssea Guiada é uma modalidade viável de tratamento, proporcionando redução do sangramento à sondagem, bem como o ganho de inserção clínica. Porém, o completo preenchimento do defeito, é um resultado imprevisível.

ABSTRACT Objective: The objective of this review was to evaluate the outcomes of the treatment of peri-implant defects, using Guided Bone Regeneration. Methods: A literature search was performed based on the PICO methodology in the PubMed/Medline, SciELO, Lilacs electronic databases, CAPES periodicals and the Cochrane Library. We included studies using bovine mineral matrix, associated to a collagen membrane for the treatment of peri-implantitis by Guided Bone Regeneration. Results: Of 1,163 studies, 10 were included in this review after applying the evaluation criteria. A total of 269 implants were treated in 260 patients. The follow-up period ranged from 6 to 48 months. The studies evaluated outcome in terms of reduction in probing depth, gain of clinical attachment and healing of the bony defect. Due to the heterogeneity of the studies, it was not possible to perform meta-analysis. Conclusion: Treatment of peri-implant lesions with Guided Bone Regeneration is a viable modality of treatment, providing reduction in bleeding on probing, as well as gain of clinical attachment. Complete filling of the defect is, however, an unpredictable result.

Resumo Substitutos ósseos têm sido amplamente utilizados para reconstrução de ossos maxilares atróficos. Uma vez que relatos anteriores demonstram a existência de células viáveis em blocos ósseos após processamento pelos bancos de tecidos músculo-esqueléticos para uso ortopédico, o objetivo deste trabalho foi avaliar a presença de células provenientes de três bancos de tecidos músculo-esqueléticos do Brasil. Todas as amostras foram processadas pelos respectivos bancos seguindo as normas da Agência Nacional de Vigilância Sanitária brasileira. Foi realizada a retirada de 3 amostras de cada bloco, que foram destinadas para processamento histológico e subsequente coloração por hematoxilina e eosina e Feugen e análise ultra-estrutural através de microscopia eletrônica de varredura (MEV). As imagens de microscopia de luz de todos os fragmentos de enxertos ósseos mostraram presença de células do tipo osteócito em todos os grupos avaliados, bem como intensa coloração por Feulgen, demonstrando a presença de DNA nos ossos mesmo após o processamento realizado. As análises ultraestruturais evidenciaram a presença de hemácias nas lacunas do tecido ósseo. Conclui-se que mesmo após os processamentos realizados pelos bancos de tecidos músculo-esqueléticos é possível encontrar células nos ossos utilizados para enxertia alógena.

Bone replacement materials have been widely used to reconstruct atrophic jawbones. Based on previous reports demonstrating the presence of viable cells in bone blocks even after processing by musculoskeletal tissue banks for orthopedic use, the aim of this study was to evaluate the presence of cells in bone blocks from three Brazilian tissue banks for maxillary reconstructions. All samples were processed by the respective tissue banks, according to the guidelines of the Brazilian National Sanitary Surveillance Agency. Three samples were removed from each block for subsequent histological processing and stained using hematoxylin & eosin. Further evaluation included section staining by the Feulgen method and ultrastructural analysis using scanning electron microscopy (SEM). Light microscopy images from all bone samples showed presence of osteocyte-like cells in all groups and intense Feulgen staining, demonstrating presence of DNA in bone even after tissue processing. The ultrastructural analysis showed red blood cells in lacunae within the bone tissue. In conclusion, despite bone tissue processing by the musculoskeletal tissue banks, cells may be found within the bone used for allogeneic grafts.

Abstract Fragile X syndrome (FXS) is the most common cause of hereditary mental retardation, but studies on the oral health condition of these patients are rare. The aim of this study was to determine the experience of dental caries in individuals with FXS, by examining the saliva profile, oral hygiene, socioeconomic characteristics and use of controlled drugs in these patients. Dental health was estimated using the decayed, missing and filled teeth index (DMF-T) and sialometry, and the pH value and buffering capacity of the saliva, colony forming units of S. mutans (CFU/mL), visible biofilm index, and socioeconomic status were all examined. The sample, comprising 23 individuals, had an average age of 17.3 ± 5.6 years, a DMF-T index of 5.5, a diminished salivary flow (78.3%), and a low (73.9%) saliva buffering capacity. Most (52.2%) individuals presented with a high abundance (CFU/mL) of S. mutans. The experience of caries was correlated with salivary parameters, poor oral hygiene, lower socioeconomic status and an increased count of S. mutans in saliva.

RESUMO Objetivo: Avaliar in vitro a proliferação de fibroblastos em superfícies radiculares, previamente condicionadas quimicamente. Métodos: Para este estudo, 40 dentes unirradiculares humanos hígidos, extraídos por acometimento periodontal irreversível, foram seccionados em fragmentos radiculares e divididos em 04 grupos (20 espécimes/grupo) de acordo com a aplicação do condicionamento ácido: GI (controle) - apenas submetidos à raspagem e alisamento radicular (RAR); GII - RAR + condicionamento com ácido cítrico a 10%; GIII- RAR + condicionamento com gel de EDTA a 24%, ph 7,0; e GIV- RAR + condicionamento com 50mg/ml de cloridrato de tetraciclina. Adicionalmente, as células foram plaqueadas sobre estas superfícies e foi avaliada a proliferação celular por meio do corante vital azul de Trypan. Para a análise da morfologia ultraestrutural foi utilizado Microscopia Eletrônica de Varredura (MEV). Resultados: Os resultados demonstraram que em relação à proliferação celular, os condicionadores químicos utilizados não foram capazes de remover efetivamente a smear layer. Entretanto, no grupo tratado com EDTA (GIII) foi observado uma maior remoção (P<0,05) na quantidade de smear layer quando comparado aos demais grupos. No grupo controle (GI) pode-se observar uma maior proliferação celular em todos os tempos (24h, 48h, 72h) quando comparado aos demais grupos que sofreram tratamento químico (P<0,05). Conclusão: Considerando os agentes desmineralizantes avaliados, a maior remoção de smear layer e proliferação celular foram alcançados com o gel de EDTA a 24%, quando comparado ao grupo condicionado com cloridrato de tetraciclina 50 mg/ml, após 72 horas de cultivo celular.

ABSTRACT Objective: The objective of the present study was to evaluate, in vitro, fibroblastic proliferation on chemically conditioned root surfaces. Methods: Forty single-rooted human teeth, were cut into fragments and divided into four groups (n=20): GI (control) - scaling and root planing (SRP); GII - SRP + conditioning with 10% citric acid; GIII - SRP + conditioning with 24% EDTA gel and GIV - SRP + conditioning with 50 mg/ml of tetracycline hydrochloride. The fibroblasts were placed on these surfaces and cell proliferation evaluated using Trypan Blue stain. Smayer layer formation was analyzed using Scanning Electron Microscopy. Results: The results revealed that the chemical conditioners used were incapable of effectively removing the smear layer. However, when compared to the other groups, GIII showed the best results regarding removal of the smear layer (p<0.05). GI demonstrated the greatest cell proliferation at all studied time intervals compared to the chemically treated groups (p<0.05). Conclusion: The results of the present study reveal that all demineralizing agents evaluated presented lower cell proliferation levels when compared to the control group. In addition none of the chemical conditioners used removed the smear layer completely.

Abstract This in vitro study evaluated the cutting ability of reciprocating files and the deformations caused by their multiple use. Five Reciproc® R25 files were divided into five groups for 10 simulated root canal preparations each. The resin blocks were weighed and photographed (12.5X and 20X) before and after preparation. The canals were prepared according to the manufacturer’s instructions. Enlargement of the root canals was evaluated by comparison of pre- and post-preparation images using a computer software. The preoperative and postoperative weight differences determined the cutting ability of repeatedly used instruments. The data were analyzed using Lilliefors and Friedman statistical tests. The cutting ability and enlargement of the canals gradually decreased after each use, with significant differences observed at the 8th and 9th repetitions, respectively. There was no evidence of file deformation. The cutting ability and enlargement of the simulated canals gradually decreased when a reciprocating file was used up to 10 times.

Objetivos: Analisar, biologicamente, a possibilidade do uso de pintura por aplicação eletrostática. Métodos: Por meio de testes in vitro de citotoxicidade, comparando o comportamento da tinta epóxi Politherm 30 Nobac C (Weg Indústrias S.A, Santa Catarina, Brasil) com CoCr polido e poliestireno em contato com cultura de fibroblastos humanos. Esse teste foi realizado através de contagem de células viáveis e não viáveis em tempos de 24, 48, 72, 94 e 120 horas. Para a contagem de células viáveis foi aplicada a Análise Estatística de Tukey. Resultados: Os resultados obtidos na presente pesquisa mostraram que o comportamento de crescimento celular foi estatisticamente semelhante entre grupos (p=0,2174). Observou-se que nos tempos de 24, 48 e 72 horas, não houve aumento estatisticamente significante da proliferação celular, mantendo-se o padrão para todos os grupos estudados. A partir de 96 e 120 h observamos um aumento da proliferação celular para todos os grupos estudados, sem diferenças entre os mesmos também (p>0,05). Para os resultados de células inviáveis, aplicou-se a Análise não Paramétrica de Kruskal Wallis e o teste de Dunn, devido à baixa taxa de morte celular, sem diferença estatisticamente entre os grupos (p>0,05). Conclusão: Conclui-se, portanto, que a pintura Epóxi estudada não apresentou citotoxicidade para os testes realizados in vitro.

Objective: To investigate the biological effect of a new method to camouflage the cobalt-chromium (CoCr) metal structure of an RPD, onto which an electrostatic paint was applied. Methods: In vitro cytotoxicity of epoxy Politherm NOBAC30C (Weg Industries SA, Santa Catarina, Brazil) in combination with polished CoCr was tested by placing it in contact with cultured human fibroblasts and comparing it with polystyrene (control surface). The cells were cultured in the presence of the test surfaces for 24, 48, 72, 94 and 120 hours. The number of viable and non-viable cells was established by manual counting. The Tukey test was used to statistically analyze cell counts between the groups. Results: The results showed that cell proliferation was similar between the groups (p =0.2174). It was observed that at 24, 48 and 72 h, there was no significant increase in cell proliferation in all groups. From 96 to 120 h, an increase in cell proliferation was observed in all groups, with no significant difference between them (p>0.05). Conclusion: The epoxy paint studied showed no cytotoxicity in vitro.

OBJETIVO Avaliar a ação do risedronato e da cobalamina, e seus efeitos quando associados, em células osteoblásticas MÉTODO Células MC3T3 foram cultivadas em meio α-MEM e α-MEM suplementado com fatores mineralizantes, ácido ascórbico e α-glicerofosfato dissódico, e tratadas com: risedronato, cobalamina, e risedronato associado à cobalamina na concentração de 10-3M. A proliferação celular e formação de nódulos de cálcio e fosfato foram avaliados após 24 horas, 48 horas, 72 horas, 5 dias e 7 dias, através de contagem em Câmara de Neubauer, vermelho de Alizarina e Reação de von Kossa RESULTADOS Os resultados mostraram que não houve diferenças significativas na curva de crescimento e formação de nódulos minerais entre as culturas analisadas CONCLUSÃO Concluiu-se que a utilização do risedronato, da cobalamina e associação de ambas em cultura de células osteoblásticas, não provocaram alterações no crescimento e formação de nódulos de cálcio e fosfato

OBJECTIVE: To evaluate the action of risedronate and cobalamin, and effects when associated, when administered osteoblastic cells. METHODS: The MC3T3 cells were cultivate in the media α-MEM and α-MEM supplemented with mineralizing factors, ascorbic acid and disodium α-glyicerophosphate, and treated with risedronate, cobalamin, and risedronate associated with cobalamin in a concentration of 10-3 M. The cell proliferation and formation of calcium and phosphate nodules were evaluated at 24 hours, 48 hours, 72 hours, 5 days and 7 days via a Neubauer Chamer count, Alizarin and the von Kossa reaction. RESULTS: The results showed that the growth curve for cell proliferation and the formation of mineral nodules was similar for both cultures analyzed. CONCLUSION: The conclusion was reached that using risedronate, cobalamin and both drugs in combination on osteoblastic cell cultures does not cause alterations to their growth or in the formation of calcium and phosphate nodules.