O objetivo foi avaliar o potencial odontogênico de células indiferenciadas da polpa (OD-21) por meio de indução química in vitro. As células foram divididas em grupos: controle (OD-21), induzido (OD-21 em meio suplementado/OD-21 + OM), e células odontoblastóides (MDPC-23). Após 3, 7, 10 e 14 dias, avaliou-se proliferação e viabilidade celular, proteína total e fosfatase alcalina (ALP), mineralização, imunolocalização da proteína da matriz dentinária 1 (DMP1), ALP e osteopontina (OPN), assim como a expressão dos genes ALP, OSTERIX (Osx), DMP1 e fator de transcrição RUNX2 por PCR em tempo real. Os dados foram avaliados pelo teste de Kruskal-Wallis seguido pelo teste de Mann-Whitney U (p<0.05). Houve diminuição na proliferação celular em OD-21 + OM, com viabilidade celular similar em todos os grupos, exceto aos sete dias. O conteúdo de proteína total foi maior no grupo OD-21 + OM em todos os períodos; o mesmo ocorreu com a atividade de ALP quando comparada com o grupo OD-21, além de apresentar resultados similares ao grupo MDPC-23. A mineralização foi maior em OD-21 + OM quando comparada com o controle negativo. A imunolocalização demonstrou expressão de DMP1 e ALP em MDPC-23 e OD-21 + OM, enquanto que todos os grupos foram positivos para OPN. A expressão gênica de DMP1 e ALP foi maior nas culturas de MDPC-23, enquanto que a de RUNX2 foi menor para estas células e maior no controle negativo. A expressão de OSTERIX foi menor em OD-21 + OM quando comparada aos outros grupos. Sugere-se que as células indiferenciadas da polpa da linhagem OD-21 apresentam potencial odontogênico e poderiam ser usadas para a engenharia tecidual

The aim of this study was to evaluate the odontogenic potential of undifferentiated pulp cells (OD-21 cell line) through chemical stimuli in vitro. Cells were divided into uninduced cells (OD-21), induced cells (OD-21 cultured in supplemented medium/OD-21+OM) and odontoblast-like cells (MDPC-23 cell line). After 3, 7, 10 and 14 days of culture, it was evaluated: proliferation and cell viability, alkaline phosphatase activity, total protein content, mineralization, immunolocalization of dentin matrix acidic phosphoprotein 1 (DMP1), alkaline phosphatase (ALP) and osteopontin (OPN) and quantification of genes ALP, OSTERIX (Osx), DMP1 and runt-related transcription factor 2 (RUNX2) through real-time polymerase chain reaction (PCR). Data were analyzed by Kruskal-Wallis and Mann-Whitney U tests (p<0.05). There was a decrease in cell proliferation in OD-21 + OM, whereas cell viability was similar in all groups, except at 7 days. The amount of total protein was higher in group OD-21 + OM in all periods; the same occurred with ALP activity after 10 days when compared with OD-21, with no significant differences from the MDPC-23 group. Mineralization was higher in OD-21+OM when compared with the negative control. Immunolocalization demonstrated that DMP1 and ALP were highly expressed in MDPC-23 cells and OD-21 + OM cells, whereas OPN was high in all groups. Real-time PCR revealed that DMP1 and ALP expression was higher in MDPC-23 cell cultures, whereas RUNX2 was lower for these cells and higher for OD-21 negative control. Osx expression was lower for OD-21 + OM. These results suggest that OD-21 undifferentiated pulp cells have odontogenic potential and could be used in dental tissue engineering.

Este estudo avaliou a resistência à tração de diferentes sistemas adesivos ao esmalte/dentina: Clearfil Liner Bond 2V - C, Prime&Bond NT/NRC - PB, Single Bond -SB and All Bond 2 -AB. Quarenta molares humanos hígidos tiveram suas coroas seccionadas no sentido mesio-lingual, e posteriormente lixadas até que fossem obtidas superfícies lisas de esmalte (E) ou dentina (D). Oitenta espécimes foi aleatoriamente dividido em 4 grupos (n=20, 10 em esmalte e 10 em dentina). Após o tratamento da superfície de acordo com cada sistema adesivo testado, um cone de resina composta Z250 (3M) foi preparado com uma matriz de Teflon®. O teste de tração foi realizado em uma máquina universal de ensaios (0.5 mm/min). As médias de resistência à tração (em MPa) foram: C - E: 18,66 (±2,67) e D: 21,62 (±5,29); PB - E: 18,13 (±2,96) e D: 3,19 (±1,40); SB - E: 20,06 (±6,11) e D: 16,95 (±2,57); AB - E: 18,20 (±3,94) e D: 15,94 (±4,72). A análise estatística (ANOVA a critérios e teste de Tukey) mostrou que C obteve os melhores resultados, seguido por SB. Concluiu-se que, dentre os materiais testados, o Clearfil Liner Bond 2V teve melhor desempenho, e que o tipo de substrato tratado influenciou na resistência adesiva, sendo esta maior em esmalte.

The aim of this study was to assess the tensile bond strength of four adhesive systems to enamel and dentin: Clearfil Liner Bond 2V - C, Prime&Bond NT/NRC - PB, Single Bond - SB and All Bond 2 -AB. For such purpose, 40 sound human molars were selected. Crowns were bisected in a mesiodistal direction and each half was ground until flat enamel (E) or dentin (D) surfaces were obtained. A total of 80 specimens were randomly assigned to 4 groups (n=20, 10 in enamel and 10 in dentin). After surface treatment, a composite resin (Z250; 3M) cone was prepared using a split Teflon® matrix. Bond strength was tested in an universal testing machine (0.5 mm/min). Bond strength means in MPa were: C - E: 18.66 (±2.67) and D: 21.62 (±5.29); PB - E: 18.13 (±2.96) and D: 3.19 (±1.40); SB - E: 20.06 (±6.11) and D: 16.95 (±2.57); AB - E: 18.20 (±3.94) and D: 15.94 (±4.72). Statistical analysis of data by two-way ANOVA showed that C presented the best results followed by SB. In conclusion, among the tested materials, Clearfil Liner Bond 2V self-etching primer adhesive syetem had the best performance. The substrate type influenced bond strength, being higher to enamel.

PROPOSIÇÃO: O objetivo deste estudo foi avaliar a dureza superficial de seis resinas compostas - Revolution, Natural Flow, Fill Magic Flow, Flow-it! (flowables), Silux Plus (micropartículas) e Z100 (híbrida) - antes e após o polimento realizado em diferentes tempos. MATERIAL E MÉTODO: Foram confeccionados 240 corpos-de-prova circulares (5mm de diâmetro e 1,4mm de altura). A dureza Vickers foi obtida antes e após o polimento realizado em diferentes tempos: imediatamente, 24 horas, 7 dias e 21 dias após a confecção do corpo-de-prova. Os dados foram analisados estatisticamente por meio da ANOVA e do Teste de Tukey. RESULTADOS: Não houve diferença entre as resinas compostas flowable, as quais apresentaram os menores valores de dureza. A resina composta híbrida demonstrou os melhores resultados. Todos os materiais exibiram aumento de dureza após a realização do polimento, que foi mais evidente após 7 dias. CONCLUSÃO: Pôde-se concluir que, independente do tipo de resina composta, a dureza superficial foi consideravelmente maior quando o polimento foi realizado 1 semana após a confecção dos corpos-de-prova.

PURPOSE: The aim of this study was to evaluate the surface hardness of six composite resins: Revolution, Natural Flow, Fill Magic Flow, Flow-it! (flowables), Silux Plus (microfilled) and Z100 (minifilled) before and after polishing at different times. MATERIALS AND METHODS: For this purpose, 240 specimens (5mm diameter, 1.4mm high) were prepared. Vickers hardness was determined before and after polishing at different times: immediately, 24h, 7 and 21 days after preparation of the samples. Statistical analysis was performed by ANOVA and Tukey test. RESULTS: There was no difference in the hardness of flowable resins, which had lower hardness than the minifilled resin. The minifilled resin showed the highest surface hardness as compared to the other materials (p<0.01). All materials exhibited higher hardness after polishing, being more evident after 7 days. CONCLUSION: It may be concluded that, regardless of the composite resin, surface hardness was considerably increased when polishing was delayed and performed 1 week after preparation of the samples.

The aim of this in vitro study was to assess the effect of different fluoride-containing mouthrinses on the translucence of resin-modified glass ionomer cements, as a function of the restorative material used, the fluoride-containing solution employed and the time of immersion. Disks were prepared (10 mm × 2 mm) with the modified glass ionomer cements Vitremer (3M) and Fuji II LC (GC Co.), and immersed in three fluoride-containing solutions: Fluordent Reach (Johnson & Johnson), Fluorgard (Colgate-Palmolive) and Oral B (Gillette do Brasil Ltda). Translucence was measured with electrophoresis equipment (JOUAN) after different immersion times. The results obtained were submitted to ANOVA and Tukey's test, and a statistically significant decrease was observed in the translucence of the materials after immersion in the fluoride-containing solutions. Fuji II LC demonstrated the lowest alteration in translucence, independently of the solution employed. Fluorgard was the fluoride-containing mouthrinse that promoted the highest alteration. It can be concluded that the fluoride-containing mouthrinses influenced the translucence of the resin-modified glass ionomer cements.