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1.
J. appl. oral sci ; 23(6): 614-622, Nov.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769822

RESUMO

ABSTRACT Plasma technology has the potential to improve the adherence of fibers to polymeric matrices, and there are prospects for its application in dentistry to reinforce the dental particulate composite. Objectives This study aimed to investigate the effect of oxygen or argon plasma treatment on polyethylene fibers. Material and Methods Connect, Construct, InFibra, and InFibra treated with oxygen or argon plasma were topographically evaluated by scanning electron microscopy (SEM), and chemically by X-ray photoelectron spectroscopy (XPS). For bending analysis, one indirect composite (Signum) was reinforced with polyethylene fiber (Connect, Construct, or InFibra). The InFibra fiber was subjected to three different treatments: (1) single application of silane, (2) oxygen or argon plasma for 1 or 3 min, (3) oxygen or argon plasma and subsequent application of silane. The samples (25x2x2 mm), 6 unreinforced and 60 reinforced with fibers, were subjected to three-point loading tests to obtain their flexural strength and deflection. The results were statistically analyzed with ANOVA and the Bonferroni correction for multiple comparison tests. Results SEM analysis showed that oxygen and argon plasma treatments promote roughness on the polyethylene fiber surface. X-ray photoelectron spectroscopy (XPS) analysis shows that both plasmas were effective in incorporating oxygenated functional groups. Argon or oxygen plasma treatment affected the flexural strength and deflection of a fiber reinforced composite. The application of silane does not promote an increase in the flexural strength of the reinforced composites. Conclusions Oxygen and argon plasma treatments were effective in incorporating oxygenated functional groups and surface roughness. The highest strength values were obtained in the group reinforced with polyethylene fibers treated with oxygen plasma for 3 min.


Assuntos
Argônio/química , Oxigênio/química , Plasma/química , Polietileno/química , Análise de Variância , Resinas Compostas/química , Colagem Dentária/métodos , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Maleabilidade , Valores de Referência , Propriedades de Superfície , Silanos/química , Fatores de Tempo
2.
J. appl. oral sci ; 23(3): 279-287, May-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-752437

RESUMO

Objective The objective of this study was to investigate the impact of two different commercially available dental implants on osseointegration. The surfaces were sandblasting and acid etching (Group 1) and sandblasting and acid etching, then maintained in an isotonic solution of 0.9% sodium chloride (Group 2). Material and Methods X-ray photoelectron spectroscopy (XPS) was employed for surface chemistry analysis. Surface morphology and topography was investigated by scanning electron microscopy (SEM) and confocal microscopy (CM), respectively. Contact angle analysis (CAA) was employed for wetting evaluation. Bone-implant-contact (BIC) and bone area fraction occupied (BAFO) analysis were performed on thin sections (30 μm) 14 and 28 days after the installation of 10 implants from each group (n=20) in rabbits' tibias. Statistical analysis was performed by ANOVA at the 95% level of significance considering implantation time and implant surface as independent variables. Results Group 2 showed 3-fold less carbon on the surface and a markedly enhanced hydrophilicity compared to Group 1 but a similar surface roughness (p>0.05). BIC and BAFO levels in Group 2 at 14 days were similar to those in Group 1 at 28 days. After 28 days of installation, BIC and BAFO measurements of Group 2 were approximately 1.5-fold greater than in Group 1 (p<0.05). Conclusion The surface chemistry and wettability implants of Group 2 accelerate osseointegration and increase the area of the bone-to-implant interface when compared to those of Group 1. .


Assuntos
Animais , Feminino , Masculino , Coelhos , Implantes Dentários , Implantação Dentária Endo-Óssea/métodos , Osseointegração/efeitos dos fármacos , Osseointegração/fisiologia , Titânio/química , Condicionamento Ácido do Dente , Materiais Biocompatíveis , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Valores de Referência , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Tíbia/efeitos dos fármacos , Molhabilidade
3.
J. appl. oral sci ; 21(4): 300-306, Jul-Aug/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-684566

RESUMO

OBJECTIVE: This study investigated the effects of different surface treatments on the tensile bond strength of an autopolymerizing silicone denture liner to a denture base material after thermocycling. MATERIAL AND METHODS: Fifty rectangular heat-polymerized acrylic resin (QC-20) specimens consisting of a set of 2 acrylic blocks were used in the tensile test. Specimens were divided into 5 test groups (n=10) according to the bonding surface treatment as follows: Group A, adhesive treatment (Ufi Gel P adhesive) (control); Group S, sandblasting using 50-µm Al2O3; Group SCSIL, silica coating using 30-µm Al2O3 modified by silica and silanized with silane agent (CoJet System); Group SCA, silica coating and adhesive application; Group SCSILA, silica coating, silane and adhesive treatment. The 2 PMMA blocks were placed into molds and the soft lining materials (Ufi Gel P) were packed into the space and polymerized. All specimens were thermocycled (5,000 cycles) before the tensile test. Bond strength data were analyzed using 1-way ANOVA and Duncan tests. Fracture surfaces were observed by scanning electron microscopy. X-ray photoelectron spectrometer (XPS) and Fourier Transform Infrared spectrometer (FTIR) analysis were used for the chemical analysis and a profilometer was used for the roughness of the sample surfaces. RESULTS: The highest bond strength test value was observed for Group A (1.35±0.13); the lowest value was for Group S (0.28±0.07) and Group SCSIL (0.34±0.03). Mixed and cohesive type failures were seen in Group A, SCA and SCSILA. Group ...


Assuntos
Bases de Dentadura , Reembasadores de Dentadura , Colagem Dentária/métodos , Materiais Dentários/química , Silanos/química , Dióxido de Silício/química , Análise de Variância , Análise do Estresse Dentário , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Polimerização/efeitos dos fármacos , Reprodutibilidade dos Testes , Propriedades de Superfície , Resistência à Tração
4.
J. appl. oral sci ; 21(4): 300-306, Jul-Aug/2013. ilus, tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-874843

RESUMO

OBJECTIVE: This study investigated the effects of different surface treatments on the tensile bond strength of an autopolymerizing silicone denture liner to a denture base material after thermocycling. MATERIAL AND METHODS: Fifty rectangular heat-polymerized acrylic resin (QC-20) specimens consisting of a set of 2 acrylic blocks were used in the tensile test. Specimens were divided into 5 test groups (n=10) according to the bonding surface treatment as follows: Group A, adhesive treatment (Ufi Gel P adhesive) (control); Group S, sandblasting using 50-µm Al2O3; Group SCSIL, silica coating using 30-µm Al2O3 modified by silica and silanized with silane agent (CoJet System); Group SCA, silica coating and adhesive application; Group SCSILA, silica coating, silane and adhesive treatment. The 2 PMMA blocks were placed into molds and the soft lining materials (Ufi Gel P) were packed into the space and polymerized. All specimens were thermocycled (5,000 cycles) before the tensile test. Bond strength data were analyzed using 1-way ANOVA and Duncan tests. Fracture surfaces were observed by scanning electron microscopy. X-ray photoelectron spectrometer (XPS) and Fourier Transform Infrared spectrometer (FTIR) analysis were used for the chemical analysis and a profilometer was used for the roughness of the sample surfaces. RESULTS: The highest bond strength test value was observed for Group A (1.35±0.13); the lowest value was for Group S (0.28±0.07) and Group SCSIL (0.34±0.03). Mixed and cohesive type failures were seen in Group A, SCA and SCSILA. Group S and SCSIL showed the least silicone integrations and the roughest surfaces. CONCLUSION: Sandblasting, silica coating and silane surface treatments of the denture base resin did not increase the bond strength of the silicone based soft liner. However, in this study, the chemical analysis and surface profilometer provided interesting insights about the bonding mechanism between the denture base resin and silicone soft liner.


Assuntos
Bases de Dentadura , Reembasadores de Dentadura , Colagem Dentária/métodos , Materiais Dentários/química , Análise de Variância , Análise do Estresse Dentário , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Polimerização/efeitos dos fármacos , Reprodutibilidade dos Testes , Propriedades de Superfície , Silanos/química , Dióxido de Silício/química , Resistência à Tração
5.
Int. j. odontostomatol. (Print) ; 6(3): 355-361, 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-676199

RESUMO

El objetivo de este estudio fue analizar la composición química y la topografía superficial de implantes de titanio comercialmente puro, obtenidos de 3 marcas comerciales utilizadas actualmente en odontología. Fueron analizados 6 implantes de titanio de los siguientes sistemas: SIN, P-I philosophy y Neodent. Este material fue dividido en 3 grupos de 3 implantes cada uno. Para determinar la composición química de la superficie fue utilizada la técnica de Espectroscopia de Fotoelectrones Excitada por rayos-X (XPS), mientras que para caracterizar la topografía superficial fue utilizada Microscopia electrónica de barrido. Titanio, Carbono Silicio y Oxigeno fueron identificados en todas las muestras analizadas. Otros elementos contaminantes identificados fueron Silicio, Aluminio, azufre, plomo, Fósforo, Calcio, Sodio, Nitrógeno y Carbono. Fueron identificadas impurezas en la superficie de todos los implantes analizados. Consideramos necesarios otros estudios que relacionen permanentemente la presencia y concentración de estos elementos con el proceso de oseointegración...


The aim of this study was to analyze the chemical composition and surface topography of commercially pure titanium implants, obtained from 03 trademarks frequently used in dentistry. There were 9 titanium implants of the following systems: SIN, P-I philosophy and Neodent. These materials were divided into 3 groups, with 3 implants in each group. Photoelectron Spectroscopy Excited by X-ray (XPS) was used to determine the chemical composition, while to characterize the surface topography we used Scanning Electron Microscopy (SEM). Titanium, carbon silicon and oxygen were identified in all samples analyzed. Other contaminants were: silicon, aluminum, sulfur, lead, phosphorus, calcium, sodium, nitrogen and carbon. We identified impurities on the surface of all implants analyzed. We consider necessary to development more studies relating the presence and concentration of these elements with the osseointegration process...


Assuntos
Humanos , Implantes Dentários , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Titânio/química , Propriedades de Superfície
6.
Braz. dent. j ; 21(1): 3-11, Jan. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-552348

RESUMO

The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H2SO4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.


O objetivo deste estudo foi caracterizar a microestrutura de uma superfície de titânio comercialmente puro (cpTi) condicionada com HCl/H2SO4 (acid etched) (AE-cpTi) e investigar sua citocompatibilidade in vitro, comparada à do cpTi usinado (turned) (T-cpTi). O T-cpTi apresentou uma superfície com sulcos e o AE-cpTi exibiu uma superfície caracterizada pela presença de micro-vales. Os parâmetros de superfície indicaram que a superfície AE-cpTi é mais isotrópica e apresenta uma área maior quando comparada à superfície T-cpTi. A espessura da camada de óxido foi similar para as duas superfícies; no entanto, a AE-cpTi apresentou maiores quantidades de Ti e O e menor, de C. A proliferação de células osteoblásticas, a atividade de fosfatase alcalina e a formação de matriz mineralizada foram maiores na superfície T-cpTi que na AE-cpTi. Esses resultados mostram que o condicionamento ácido produziu uma superfície com características topográficas e químicas diferentes quando comparadas às da superfície usinada. Além disso, observou-se que essas modificações de superfície afetaram de forma negativa a citocompatibilidade in vitro do cpTi como demonstrado pela inibição da proliferação celular e da expressão do fenótipo osteoblástico.


Assuntos
Humanos , Condicionamento Ácido do Dente , Materiais Biocompatíveis/farmacologia , Materiais Dentários/farmacologia , Osteoblastos/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/análise , Processo Alveolar/citologia , Materiais Biocompatíveis/química , Biomarcadores/análise , Células Cultivadas , Carbono/química , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Materiais Dentários/química , Ácido Clorídrico/química , Interferometria , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese/efeitos dos fármacos , Fenótipo , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Ácidos Sulfúricos/química , Titânio/química
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