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Alonso, Roberta Caroline Bruschi
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Id: biblio-1019969
Autor: Paula, Andreia Bolzan de; Alonso, Roberta Caroline Bruschi; Taparelli, Jesus Roberto; Camassari, Jéssica Rodrigues; Innocentini-Mei, Lúcia Helena; Correr-Sobrinho, Lourenço; Puppin-Rontani, Regina M.
Título: Influence of the incorporation of triclosan methacrylate on the physical properties and antibacterial activity of resin composite
Fonte: J. appl. oral sci;27:e20180262, 2019. tab.
Idioma: en.
Projeto: FAPESP.
Resumo: Abstract The incorporation of antimicrobials in the composites as an attempt to reduce bacterial adhesion without jeopardizing mechanical properties is a challenge for Dentistry. Objective: To evaluate the bacterial adhesion and physical properties of a composite containing the methacrylate triclosan- derivative monomer (TM). Methodology: TM was synthesized and added to an experimental composite. Samples were divided into two groups: Control and TM (13.4 wt%). Antibacterial Activity: Three specimens of each material were prepared and placed on bacterial suspensions of Streptococcus mutans for 1, 5 and 10 days. After these periods the counting of the colonies (log10) was performed. Assays was performed in triplicate. Physical Properties: Three-body Abrasion (TBA): Ten specimens of each material were prepared and stored at 37°C/24 h. The surface roughness (Ra) and hardness (KHN) were analyzed. Next, the specimens were submitted to abrasive wear (30,000 cycles) and re-evaluated for Ra and KHN; Sorption/solubility (SS): cylindrical specimens (n=10) were prepared and weighted. The specimens were immersed in deionized water for 7 days at 37°C and then their weight was verified again. SS were calculated using accepted formulas; Diametral tensile strength (DTS): specimens (n=10) underwent test performed in an Instron universal testing machine at a crosshead speed of 1 mm/min. Data were submitted to appropriate statistical tests according to data distribution and assay (p<0.05). Results: Bacterial Adhesion: TM showed a significant reduction on biofilm accumulation in the evaluated periods: 1 day (1.537±0.146); 5 days (2.183±0.138) and 10 days (4.469±0.155) when compared with Control: 1 day (4.954±0.249); 5 days (5.498±0.257) and 10 days (6.306±0.287). Physical Properties: For TBA, SS and DTS no significant difference was found between groups Control and TM. The incorporation of methacrylate triclosan-based monomer in the experimental composite reduce bacterial adhesion of S. mutans and did not affect important polymer properties.
Descritores: Triclosan/química
Resinas Compostas/química
Metacrilatos/química
Antibacterianos/química
-Valores de Referência
Solubilidade
Streptococcus mutans/efeitos dos fármacos
Propriedades de Superfície
Resistência à Tração
Fatores de Tempo
Escovação Dentária
Triclosan/farmacologia
Aderência Bacteriana/efeitos dos fármacos
Teste de Materiais
Contagem de Colônia Microbiana
Reprodutibilidade dos Testes
Resinas Compostas/farmacologia
Testes de Dureza
Metacrilatos/farmacologia
Antibacterianos/farmacologia
Tipo de Publ: Estudo de Avaliação
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Id: biblio-1019971
Autor: Lopes, Fabiane Carneiro; Zangirolami, Caio; Mazzi-Chaves, Jardel Francisco; Silva-Sousa, Alice Corrêa; Crozeta, Bruno Monguilhott; Silva-Sousa, Yara Teresinha Corrêa; Sousa-Neto, Manoel Damião.
Título: Effect of sonic and ultrasonic activation on physicochemical properties of root canal sealers
Fonte: J. appl. oral sci;27:e20180556, 2019. tab, graf.
Idioma: en.
Resumo: Abstract Objective: To evaluate the effect of ultrasonic and sonic activation on physicochemical properties of AH Plus, MTA Fillapex, ADSeal, GuttaFlow Bioseal, and GuttaFlow 2 sealers. Methodology: Three experimental groups were formed: no activation (NA), ultrasonic activation (UA), and sonic activation (SA). The sealers were manipulated according to the manufacturers' instructions. A 3-mL syringe was adapted to receive 1 mL of sealer. Activation was performed with a 20/.01 ultrasonic insert (20 s/1W) in the UA group. A size 35.04 sonic tip was used (20 s/10,000 cycles/min-1) in the SA group. The molds for physicochemical analysis were filled and evaluated according to ANSI/ADA specification no. 57: setting time (ST), flow (FL), dimensional change (DC), solubility (SB), and radiopacity (RD). Statistical analysis was performed by Kruskal-Wallis, one-way ANOVA, and Tukey's tests (P<0.05). Results: Regarding ST, only AH Plus and GuttaFlow 2 in the NA group met the ANSI/ADA standards. All FL values were greater than 20 mm in diameter, as determined by ANSI/ADA. The tested sealers and protocols did not comply with the ANSI/ADA standards for DC. As for SB, only MTA Fillapex, regardless of the activation protocol, did not follow the ANSI/ADA standards. All of the investigated sealers, regardless of the activation protocol, presented radiographic density higher than 3 mm Al, as proposed by ANSI/ADA. Conclusions: UA and SA promoted changes in the physicochemical properties of the evaluated root canal sealers, mainly in ST and F. Thus, it is important to evaluate the physicochemical properties of endodontic sealers associated with activation techniques prior to clinical application in order to determine whether the properties follow the parameters set by ANSI/ADA, ensuring safety and quality of root canal filling.
Descritores: Óxidos/química
Materiais Restauradores do Canal Radicular/química
Silicatos/química
Compostos de Cálcio/química
Compostos de Alumínio/química
Dimetilpolisiloxanos/química
Resinas Epóxi/química
Ondas Ultrassônicas
Guta-Percha/química
-Valores de Referência
Solubilidade
Propriedades de Superfície
Fatores de Tempo
Teste de Materiais
Reprodutibilidade dos Testes
Análise de Variância
Estatísticas não Paramétricas
Combinação de Medicamentos
Tipo de Publ: Estudo de Avaliação
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Id: biblio-1019973
Autor: Eidt, Gustavo; Andrade, Caroline Gomes de; Negrini, Thais de Cássia; Arthur, Rodrigo Alex.
Título: Role of Candida albicans on enamel demineralization and on acidogenic potential of Streptococcus mutans in vitro biofilms
Fonte: J. appl. oral sci;27:e20180593, 2019. tab, graf.
Idioma: en.
Resumo: Abstract There is growing evidence that C. albicans is associated with dental caries, but its role on caries development needs to be better clarified. Objective: To evaluate at the hard tissue level the effect of C. albicans on the cariogenic potential of S. mutans biofilms focusing on the mineral profile of induced carious lesions. This study also aimed to evaluate the effect of C. albicans on the acidogenic potential of S. mutans biofilms. Methodology: Dual-species (CA+SM) and single-species biofilms (CA or SM) were grown on the surface of enamel slabs in the presence of glucose/sucrose supplemented culture medium for 24, 48 and 72 hours. Demineralization was evaluated through percentage of surface microhardness change (%SMC) and transversal microradiography analysis (ILM and LD) and pH of the spent medium was recorded daily. Data were analyzed by two-way ANOVA followed by Bonferroni correction. Results: %SMC was statistically different among the biofilms at each time point being the highest for SM biofilms and the lowest for CA biofilms which also differed from CA+SM biofilms [SM (24 h: 47.0±7.3; 48 h: 66.3±8.3; 72 h: 75.4±3.9); CA (24 h: 7.3±3.3; 48 h: 7.1±6.4; 72 h: 6.6±3.6); CA+SM (24 h: 35.9±7.39.1; 48 h: 47.2±9.5; 72 h: 47.6±9.5)]. pH of spent medium was statistically lower for SM biofilms compared to the other biofilms at each time point and remained constant over time while pH values increased from 24 to 72 h for both CA and CA+SM biofilms [SM (24 h: 4.4±0.1; 48 h: 4.4±0.1; 72 h: 4.5±0.1); CA (24 h: 6.9±0.3; 48 h: 7.2±0.2; 72 h: 7.5±0.2); CA+MS (24 h: 4.7±0.2; 48 h: 5.1±0.1; 72 h: 6.1±0.6)]. IML and LD for SM biofilms increased over time while no difference was observed from 24 to 72 h for the other biofilms. Conclusions: The present data suggest that C. albicans has low enamel demineralization potential and the presence of C. albicans can reduce both the cariogenic and acidogenic potentials of S. mutans biofilms.
Descritores: Streptococcus mutans/metabolismo
Candida albicans/fisiologia
Desmineralização do Dente/microbiologia
Biofilmes/crescimento & desenvolvimento
Esmalte Dentário/microbiologia
-Valores de Referência
Propriedades de Superfície
Fatores de Tempo
Ácidos/metabolismo
Microrradiografia/métodos
Contagem de Colônia Microbiana
Esmalte Dentário/química
Testes de Dureza
Concentração de Íons de Hidrogênio
Limites: Animais
Bovinos
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Id: biblio-1040232
Autor: Fouda, Shaimaa M; Gad, Mohammed M; Ellakany, Passent; Al-Thobity, Ahmad M; Al-Harbi, Fahad A; Virtanen, Jorma I; Raustia, Aune.
Título: The effect of nanodiamonds on candida albicans adhesion and surface characteristics of PMMA denture base material - an in vitro study
Fonte: J. appl. oral sci;27:e20180779, 2019. tab, graf.
Idioma: en.
Resumo: Abstract Candida albicans is the main causative pathogen of denture stomatitis, which affects many complete denture patients. Objective: To evaluate the effect of different concentrations of nanodiamonds (NDs) added to polymethyl methacrylate (PMMA) denture base material on Candida albicans adhesion as well as on surface roughness and contact angle. Methodology: Acrylic resin specimens sized 10×10×3 mm3 were prepared and divided into four groups (n=30) according to ND concentration (0%, 0.5%, 1%, 1.5% by wt). Surface roughness was measured with a profilometer, and the contact angle with a goniometer. The effect of NDs on Candida albicans adhesion was evaluated using two methods: 1) slide count and 2) direct culture test. Analysis of variance (ANOVA) and Tukey's post hoc test were used in the statistical analyses. Results: Addition of NDs decreased the Candida albicans count significantly more than in the control group (p<0.05), with a lowest of 1% NDs. Addition of NDs also significantly decreased the surface roughness (p<0.05), but the contact angle remained the same. Incorporation of NDs into the PMMA denture base material effectively reduced Candida albicans adhesion and decreased surface roughness. Conclusion: PMMA/NDs composites could be valuable in the prevention of denture stomatitis, which is considered one of the most common clinical problems among removable denture wearers.
Descritores: Resinas Acrílicas/química
Candida albicans/efeitos dos fármacos
Polimetil Metacrilato/química
Bases de Dentadura/microbiologia
Nanodiamantes/microbiologia
Nanodiamantes/química
-Valores de Referência
Estomatite sob Prótese/microbiologia
Estomatite sob Prótese/prevenção & controle
Propriedades de Superfície
Teste de Materiais
Microscopia Eletrônica de Varredura
Reprodutibilidade dos Testes
Análise de Variância
Limites: Humanos
Tipo de Publ: Estudo de Avaliação
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Amaral, Cristiane Mariote
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Id: biblio-1101251
Autor: MIRANDA, Maria Elisa da Silva Nunes Gomes; SILVA, Eduardo Moreira da; OLIVEIRA, Mariana Flôres de; SIMMER, Fabiana Souza; SANTOS, Glauco Botelho dos; AMARAL, Cristiane Mariote.
Título: Resin-dentin bond stability of etch-and-rinse adhesive systems with different concentrations of MMP inhibitor GM1489
Fonte: J. appl. oral sci;28:e20190499, 2020. tab, graf.
Idioma: en.
Projeto: CAPES.
Resumo: Abstract Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher μTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.
Descritores: Polietilenoglicóis/química
Ácidos Polimetacrílicos/química
Cimentos Dentários/química
Dentina/química
Inibidores de Metaloproteinases de Matriz/química
Metacrilatos/química
-Valores de Referência
Propriedades de Superfície
Resistência à Tração
Fatores de Tempo
Teste de Materiais
Reprodutibilidade dos Testes
Análise de Variância
Colagem Dentária/métodos
Espectroscopia de Infravermelho com Transformada de Fourier
Estatísticas não Paramétricas
Infiltração Dentária
Dentina/efeitos dos fármacos
Corrosão Dentária/métodos
Limites: Humanos
Tipo de Publ: Estudo de Avaliação
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Texto completo
Id: biblio-1090787
Autor: YOSHIDA, Keiichi.
Título: Influence of alumina air-abrasion for highly translucent partially stabilized zirconia on flexural strength, surface properties, and bond strength of resin cement
Fonte: J. appl. oral sci;28:e20190371, 2020. tab, graf.
Idioma: en.
Resumo: Abstract Objective This study aims to evaluate the influence of different air-abrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. Methodology Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. Results The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal ( t )-, and rhombohedral ( r )-ZrO2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r -ZrO2 phase increased, with a significant amount of r -ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t -ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. Conclusion Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.
Descritores: Zircônio/química
Colagem Dentária/métodos
Cimentos de Resina/química
Abrasão Dental por Ar/métodos
Óxido de Alumínio/química
-Valores de Referência
Propriedades de Superfície
Resistência à Tração
Difração de Raios X/métodos
Teste de Materiais
Reprodutibilidade dos Testes
Análise de Variância
Microscopia Confocal/métodos
Resistência à Flexão
Temperatura Alta
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


  7 / 979 LILACS  
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Buzalaf, Marilia Afonso Rabelo
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Id: biblio-1090782
Autor: SIMÕES, Ana Clara Correa Duarte; DIONIZIO, Aline; CÂMARA, João Victor Frazão; SABINO-ARIAS, Isabela Tomazini; LEVY, Flávia Mauad; VENTURA, Talita Mendes Oliveira; BUZALAF, Nathalia Rabelo; BATISTA, Thiago Beltrami Dias; MAGALHÃES, Ana Carolina; GROISMAN, Sonia; BUZALAF, Marília Afonso Rabelo.
Título: Do commercial whitening dentifrices increase enamel erosive tooth wear?
Fonte: J. appl. oral sci;28:e20190163, 2020. tab, graf.
Idioma: en.
Projeto: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.
Resumo: Abstract Objective This in vitro study evaluated the effect of commercial whitening dentifrices on erosive tooth wear (ETW) of bovine enamel samples, in comparison with commercial regular dentifrices. Methodology Sixty bovine crowns were embedded in acrylic resin, polished and then had their baseline profile determined. They were randomly assigned to 5 groups (n=12/group), according to the type of commercial dentifrice to be tested: GI - Crest Anti-cavity Regular; GII - Crest 3D White; GIII - Colgate Total 12 Clean Mint; GIV - Colgate Optic White; GV - Placebo (negative control, fluoride-free dentifrice). The samples were submitted to daily erosive and abrasive challenges for 3 days. The erosive challenges were performed 3 times a day by immersing the specimens in 0.1% citric acid solution (pH 2.5) for 90 s. Each day after the first and last erosive challenges, the specimens were subjected to the abrasive challenge for 15 s, using a toothbrushing machine (Biopdi, São Carlos, SP, Brazil), soft toothbrushes and slurry (1:3 g/ml) of the tested toothpastes (1.5 N). The specimens were kept in artificial saliva between the challenges. The final profile was obtained and the ETW (µm) was calculated. Data were analyzed by Kruskal-Wallis and Dunn's tests (p<0.05). Results All dentifrices tested significantly reduced the enamel wear in comparison with the Placebo, except GIII. The median (95% CI) ETW was 1.35 (1.25-1.46)bc for GI, 1.17 (1.01-1.34)cd for GII, 1.36 (1.28-1.45)ab for GIII, 1.08 (1.04-1.14)d for GIV and 2.28 (2.18-2.39)a for GV. Conclusion When dentifrices from the same manufacturer were compared, the whitening dentifrices led to similar or less wear than the regular ones.
Descritores: Erosão Dentária/induzido quimicamente
Cremes Dentais/efeitos adversos
Esmalte Dentário/efeitos dos fármacos
Clareadores Dentários/efeitos adversos
-Propriedades de Superfície
Fatores de Tempo
Escovação Dentária/efeitos adversos
Cremes Dentais/química
Teste de Materiais
Estatísticas não Paramétricas
Esmalte Dentário/química
Clareadores Dentários/química
Limites: Animais
Bovinos
Tipo de Publ: Estudo de Avaliação
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Id: biblio-1090766
Autor: AYOUB, Hadeel M; GREGORY, Richard L; TANG, Qing; LIPPERT, Frank.
Título: Influence of salivary conditioning and sucrose concentration on biofilm-mediated enamel demineralization
Fonte: J. appl. oral sci;28:e20190501, 2020. tab.
Idioma: en.
Resumo: Abstract The acquired pellicle formation is the first step in dental biofilm formation. It distinguishes dental biofilms from other biofilm types. Objective To explore the influence of salivary pellicle formation before biofilm formation on enamel demineralization. Methodology Saliva collection was approved by Indiana University IRB. Three donors provided wax-stimulated saliva as the microcosm bacterial inoculum source. Acquired pellicle was formed on bovine enamel samples. Two groups (0.5% and 1% sucrose-supplemented growth media) with three subgroups (surface conditioning using filtered/pasteurized saliva; filtered saliva; and deionized water (DIW)) were included (n=9/subgroup). Biofilm was then allowed to grow for 48 h using Brain Heart Infusion media supplemented with 5 g/l yeast extract, 1 mM CaCl2.2H2O, 5% vitamin K and hemin (v/v), and sucrose. Enamel samples were analyzed for Vickers surface microhardness change (VHNchange), and transverse microradiography measuring lesion depth (L) and mineral loss (∆Z). Data were analyzed using two-way ANOVA. Results The two-way interaction of sucrose concentration × surface conditioning was not significant for VHNchange (p=0.872), ∆Z (p=0.662) or L (p=0.436). Surface conditioning affected VHNchange (p=0.0079), while sucrose concentration impacted ∆Z (p<0.0001) and L (p<0.0001). Surface conditioning with filtered/pasteurized saliva resulted in the lowest VHNchange values for both sucrose concentrations. The differences between filtered/pasteurized subgroups and the two other surface conditionings were significant (filtered saliva p=0.006; DIW p=0.0075). Growing the biofilm in 1% sucrose resulted in lesions with higher ∆Z and L values when compared with 0.5% sucrose. The differences in ∆Z and L between sucrose concentration subgroups was significant, regardless of surface conditioning (both p<0.0001). Conclusion Within the study limitations, surface conditioning using human saliva does not influence biofilm-mediated enamel caries lesion formation as measured by transverse microradiography, while differences were observed using surface microhardness, indicating a complex interaction between pellicle proteins and biofilm-mediated demineralization of the enamel surface.
Descritores: Saliva/química
Sacarose/química
Desmineralização do Dente/microbiologia
Biofilmes/crescimento & desenvolvimento
Esmalte Dentário/microbiologia
-Valores de Referência
Saliva/microbiologia
Sacarose/análise
Propriedades de Superfície
Microrradiografia/métodos
Esmalte Dentário/química
Película Dentária/microbiologia
Pasteurização
Dureza
Limites: Animais
Bovinos
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


  9 / 979 LILACS  
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Rosa, Adalberto Luiz
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Id: biblio-1090765
Autor: LOPES, Helena Bacha; SOUZA, Alann Thaffarell Portilho; FREITAS, Gileade Pereira; ELIAS, Carlos Nelson; ROSA, Adalberto Luiz; BELOTI, Marcio Mateus.
Título: Effect of focal adhesion kinase inhibition on osteoblastic cells grown on titanium with different topographies
Fonte: J. appl. oral sci;28:e20190156, 2020. graf.
Idioma: en.
Projeto: FAPESP; . FAPESP; . FAPESP.
Resumo: Abstract Objective The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). Methodology Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. Results FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. Conclusions Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.
Descritores: Osteoblastos/efeitos dos fármacos
Sulfonas/farmacologia
Titânio/química
Quinolonas/farmacologia
Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores
-Osteoblastos/fisiologia
Sulfonas/química
Propriedades de Superfície
Microscopia Eletrônica de Varredura
Transdução de Sinais
Expressão Gênica
Integrinas/análise
Diferenciação Celular/efeitos dos fármacos
Células Cultivadas
Osseointegração/efeitos dos fármacos
Ratos Wistar
Quinolonas/química
Proliferação de Células/efeitos dos fármacos
Proteína-Tirosina Quinases de Adesão Focal/análise
Proteína-Tirosina Quinases de Adesão Focal/química
Reação em Cadeia da Polimerase em Tempo Real
Limites: Animais
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta


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Id: biblio-1056595
Autor: YOSHIDA, Keiichi.
Título: Influence of alumina air-abrasion for highly translucent partially stabilized zirconia on flexural strength, surface properties, and bond strength of resin cement
Fonte: J. appl. oral sci;28:e20190371, 2020. tab, graf.
Idioma: en.
Resumo: Abstract Objective This study aims to evaluate the influence of different air-abrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. Methodology Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. Results The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal ( t )-, and rhombohedral ( r )-ZrO2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r -ZrO2 phase increased, with a significant amount of r -ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t -ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. Conclusion Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.
Descritores: Zircônio/química
Colagem Dentária/métodos
Cimentos de Resina/química
Abrasão Dental por Ar/métodos
Óxido de Alumínio/química
-Valores de Referência
Propriedades de Superfície
Resistência à Tração
Difração de Raios X/métodos
Teste de Materiais
Reprodutibilidade dos Testes
Análise de Variância
Microscopia Confocal/métodos
Resistência à Flexão
Temperatura Alta
Responsável: BR28.1 - Serviço de Biblioteca e Documentação Professor Doutor Antônio Gabriel Atta



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