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1.
Chinese Journal of Primary Medicine and Pharmacy ; (12): 1118-1120, 2022.
Artículo en Chino | WPRIM | ID: wpr-955810

RESUMEN

In the past few decades, some studies reported that changing the specific surface properties of titanium implants, such as surface morphology, surface chemistry, surface charge and wettability, improved the bone bonding ability of titanium implants. Based on the existing evidence, this review paper analyzes the methods and characteristics of surface chemical modification of the superhydrophilic implants (Thommen INICELL?) that were listed in China in recent years, and clarifies the process of early osseointegration from the viewpoint of histomorphology, and evaluates its clinical application effects.

2.
Araçatuba; s.n; 2019. 90 p. ilus, tab.
Tesis en Portugués | LILACS, BBO | ID: biblio-1402483

RESUMEN

Objetivo: O objetivo do estudo foi avaliar o efeito da aplicação de ácido fluorídrico com diferentes tempos e concentrações na superfície de materiais restauradores indiretos obtidos a partir de blocos utilizados na tecnologia CAD-CAM. Materiais e Métodos: Amostras dos materiais restauradores indiretos medindo 4x4x0,8mm foram obtidos a partir de blocos CAD para cada material estudado: resina nanocerâmica Lava Ultimate (3M Espe), monossilicato de lítio reforçado por zircônia Celtra Duo (Dentsply) e cerâmica híbrida Vita Enamic (Vita). Os materiais foram submetidos à aplicação de ácido fluorídrico com concentração de 5% ou 10%, sendo o mesmo aplicado pelos tempos de 20, 40, 60 ou 90 segundos. Um grupo controle para cada material foi avaliado, sem nenhum tratamento de superfície, contabilizando nove grupos de cada material (n=10). As amostras foram avaliadas em relação à rugosidade de superfície (Ra e Rz), avaliadas em microscopia óptica confocal; ângulo de contato (θ), energia de superfície (s) e energia livre total de interação (∆G) avaliados em goniômetro, e resistência de união ao cimento resinoso avaliada através do teste de microcisalhamento. Imagens das amostras foram obtidas em microscopia eletrônica de varredura (MEV), microscopia óptica confocal e microscopia de força atômica. Os dados de rugosidade de superfície, ângulo de contato, energia de superfície, energia livre total de interação e resistência de união foram submetidos à ANOVA dois fatores e teste de Tukey (p<0,05). Resultados: Os resultados mostraram que, de maneira geral, o monosilicato de lítio reforçado por zircônia Celtra Duo apresentou melhores resultados quando submetido ao condicionamento com ácido fluorídrico 10% por 40 ou 60 segundos de aplicação. A resina nanocerâmica Lava Ultimate apresentou melhor performance quando condicionada com ácido fluorídrico 10% por 20 ou 40 segundos, enquanto que a cerâmica híbrida Vita Enamic apresentou melhores resultados quando condicionada com ácido fluorídrico 5% por 90 segundos. Conclusão: Cada material interagiu de maneira diferente ao condicionamento com ácido fluorídrico, sendo que o conhecimento do adequado protocolo para cada material é essencial para garantir melhorias nos processos de adesão e durabilidade das restaurações indiretas. Celtra Duo apresentou de maneira geral propriedades mecânicas superiores aos demais. Relevância clínica: Recomenda-se protocolos específicos de tratamento de superfície com ácido fluorídrico de acordo com a composição de cada material restaurador indireto(AU)


Purpose: The aim of this study was to evaluate the effect of different times and concentration of hydrofluoric acid etching on the surface of indirect restorative materials obtained from blocks used in CAD-CAM technology. Methods and Materials: Samples of indirect restorative materials measuring 4x4x0.8mm were obtained for each restorative material studied: Lava Ultimate nanoceramic resin (3M Espe), Celtra Duo zirconia-reinforced lithium silicate ceramic (Dentsply) and Vita Enamic polymer-infiltrated ceramic-network material (Vita). The materials were submitted to etching with 5% or 10% hydrofluoric acid for 20, 40, 60 or 90 seconds. A control group for each material was evaluated without any surface treatment, totaling nine experimental groups for each material (n = 10). The samples were evaluated in relation to surface roughness (Ra and Rz), evaluated by confocal optical microscopy; contact angle (θ), surface energy (s) and total free interaction energy (∆G) evaluated by goniometer; and microshear bond strength to resin cement. Sample images were obtained by scanning electron microscopy (SEM), confocal optical microscopy and atomic force microscopy. Data of surface roughness, contact angle, surface energy, total free interaction energy and bond strength were submitted to two-way ANOVA and Tukey test (p<0.05). Results: The results showed that, in general, the Celtra Duo zirconia-reinforced lithium silicate ceramic showed better results when subjected to etching with 10% hydrofluoric acid for 40 or 60 seconds. Lava Ultimate nanoceramic resin showed better performance when etched with 10% hydrofluoric acid for 20 or 40 seconds, while Vita Enamic polymer-infiltrated ceramic-network showed better results when etched with 5% hydrofluoric acid for 90 seconds. Conclusion: Each material showed different characteristics after etching with hydrofluoric acid, and the knowledge of the proper protocol for each material is essential to ensure improvements in the adhesion process and durability of indirect restorations. Celtra Duo presents general ways of mechanical properties superior to the others. Clinical relevance: Specific surface treatment protocols with hydrofluoric acid are recommended based on the different compositions of indirect restorative materials(AU)


Asunto(s)
Propiedades de Superficie , Cerámica , Cementos de Resina , Ácido Fluorhídrico , Microscopía Electrónica de Rastreo , Microscopía de Fuerza Atómica , Resinas , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía
3.
Journal of Korean Dental Science ; : 5-13, 2018.
Artículo en Inglés | WPRIM | ID: wpr-764780

RESUMEN

PURPOSE: Surface treatment with pH buffering agent has been developed to achieve higher and faster osseointegration. The aim of this study was to evaluate its influence by measuring removal torque and analyzing histological characteristics. MATERIALS AND METHODS: Titanium implants with following surfaces were used in this study: sand-blasted acid-etched (SA) surface (SA group as control I group), SA surface in calcium chloride aqueous solution (CA group as control II group) and SA surface coated with pH buffering agent (pH group as test group). Removal torque test after 2 weeks and bone-to-implant contact and bone area analyses at 2 and 4 weeks were performed. RESULT: The rotational torque values at 2 weeks were significantly higher in pH group (107.5±6.2 Ncm, P < 0.05). The mean values of bone-to-implant contact at 2 and 4 weeks were both higher in pH group (93.0%±6.4% at 2 weeks, 88.6%±5.5% at 4 weeks) than in SA group (49.7%±9.7% at 2 weeks, 47.3%±20.1% at 4 weeks) and CA group (73.7%±12.4% at 2 weeks, 72.5%±10.9% at 4 weeks) with significances (P < 0.05). The means of bone area showed significantly higher numbers in pH group (39.5%±11.3% at 2 weeks, 71.9%±10.9% at 4 weeks, P < 0.05). CONCLUSION: Our findings demonstrated that surface modification with pH buffering agent improved early osseointegration with superior biomechanical property.


Asunto(s)
Cloruro de Calcio , Implantes Dentales , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Oseointegración , Estadística como Asunto , Propiedades de Superficie , Titanio , Torque
4.
Chinese Journal of Experimental Ophthalmology ; (12): 248-253, 2016.
Artículo en Chino | WPRIM | ID: wpr-637681

RESUMEN

Background Phacoemulsification with IOL implantation can reduce the light scattering caused by cataract,but many patients with IOLs implantation complained of glare or blurred vision.IOLs from different materials will affect IOL refractive index (RI) and optical design,which affect the value of scattered light of IOLs implantation.Objective This study was to analyze the effect of IOL materials on optical quality in pseudophakic eyes with optical quality analysis system (OQAS).Methods The clinical data of 95 eyes from 65 patients with age-related cataract who received phacoemulcification with IOL implantation in Tianjin Eye Hospital from March to Octomber were retropectively analyzed.Three types of lOL,including AR40e,Acrysof SA60 AT and Rayner 620H,were implanted in 32 eyes,30 eyes and 33 eyes,respectively.The visual quality indexes were detected and evaluated using OQAS,including uncorrected distance visual acuity (UCDVA,LogMAR),objective scatter index (OSI),modulation transfer function cut off (MTF cut off),strehl ratio (SR),Profile width at 50% point scatter function (PSF),Profile width at 10% PSF and contrast visual acuity under the 100%,20%,9% contrasts.Results The UCDVA was ≥ 0.3 in the eyes of AR40e group,SA60AT group and 620H group 1 month after surgery.No significant difference was found in the best corrected distance visual acuity (BCDVA,LogMAR) among three groups (F =1.362,P =0.246).The OSI was 1.72±1.11,1.89±1.07 and 2.13±1.13 in the AR40e group,SA60AT group and 620H group,with a significant difference among the groups (F =3.638,P =0.045),and the OSI was significantly lower in the AR40e group than that in the SA60AT group or 620H group (both at P<0.05).No considerable difference in MTF cut off among the groups (F =2.401,P =0.192).The SR value was significantly elevated and the PSF at both 50% and 10% was declined in the AR40e group compared with the SA60AT group and 620H group (all at P<0.05).A significant difference was found in 9% contrast visual acuity among the three groups (F=3.866,P=0.038),and 9% contrast visual acuity was better in the AR40e group than that in the SA60At group or the 620H group (both at P< 0.05).Negative correlations were found betwee OSI and BCDVA in the AR40e group,SA60AT group and 620H group (r=-0.275,P=0.041;r=-0.287,P=0.042;r=-0.233,P=0.037).Conclusions OQAS can evaluate optical quality of cataract patients after opeartion objectively.Material and RI of IOL have a great effect on visual quality after phacoemulcification with IOL implantation,especially under the low contrast environment.The operated eyes implanted hydrophobic acrylic IOLs with a lower RI can get better optical quality in comparison with the eyes implanted hydrophilic IOLs.

5.
Araraquara; s.n; 2014. 140 p. ilus, tab, graf.
Tesis en Portugués | LILACS, BBO | ID: biblio-867832

RESUMEN

Este estudo comparou as propriedades de superfície e a adesão Streptococcus mutans na liga Ti-35Nb-7Zr-5Ta e no titânio comercialmente puro (Ti cp) antes e após a anodização. Foram utilizados discos (Ø8mmx2mm; N = 40) divididos em 2 grupos: T (Ti cp), TNZT (Ti-35Nb7Zr-5Ta), e subdivididos conforme a realização (A+) ou não (A-, controle) da anodização eletroquímica (300 V, 1 min) em ß-glicerofostato de sódio + acetato de cálcio. As propriedades avaliadas foram: topografia de superfície e identificação qualitativa dos elementos químicos (microscópio eletrônico de varredura-MEV/EDS), energia livre de superfície (ELS, mensurada em goniômetro) e rugosidade média (Ra, determinada em rugosímetro). Para avaliação da adesão bacteriana, os discos foram contaminados com Streptococcus mutans (NTCC 25175) para determinação de UFC/mL e do padrão de adesão (MEV). Os valores de Ra e ELS de cada grupo foram comparados (Avs. A+ ) por meio do teste Kruskal-Wallis associado ao teste de Dun (α = 0,05). Os valores de Ra (µm) e ELS (mN/m), respectivamente, foram: A- - T=0,97/44,24; TNZT=0,17/36,68; A+ - T=1,21/56,88; TNZT=0,53/53,64, com aumento significante de ambas propriedades (p < 0,05) após a anodização. A análise em MEV/EDS indicou a formação de uma camada multiporosa, com deposição de íons Ca e P nos subgrupos A+ . Após a anodização houve aumento na adesão do patógeno apenas na liga TNZT. Conclui-se que a anodização do Ti cp e da liga TNZT alteram as propriedades de superfície com potencial para melhorias na osseointegração, contudo há aumento na adesão de S. mutans na liga TNZT


The aim of this study was to compare the surface properties and the adhesion of Streptococcus mutans on Ti-35Nb-7Zr-5Ta and commercially pure titanium (cp Ti) before and after the anodization. Discs (Ø8mmx2mm, N=40) were divided into 2 groups: T (cp Ti), TNZT (Ti-35Nb-7Zr5Ta), and subdivided in untreated (A- , control) or anodic treated (A+ ) in ßglicerofostato + calcium acetate (300 V, 1min). The evaluated surface properties were: surface topography and qualitative identification of chemical elements (in scanning electron microscope -SEM/EDS), surface free energy (SFE, measured with a goniometer), and the average roughness (Radetermined in profimoleter). The discs were contaminated with Streptococcus mutans (NTCC 25175) for determination of CFU/mL; the surfaces with adhered viable cell were also analyzed with SEM. The values of Ra and ELS were compared (Avs . A+ ) by means of Kruskal-Wallis associated Dun test (α=0.05). The median Ra (µm) and ELS (mN/m), respectively, were: A-T=0.97/44.24; TNZT=0.17/36.68; A+ T=1.21/56.88; TNZT=0.53/ 53.64. All groups showed significantly higher values of Ra and ELS (p < 0.05) after anodizing. The analysis in SEM/EDS indicated the formation of a multiporous layer with deposition of Ca and P ions. Only anodic treated TNZT exhibited an increase in adhesion of S. mutans. It was concluded that the anodic tretament of Ti cp and TNZT change the surface properties with potential improvements for osseointegration, despite the increase in the adhesion of S. mutans on TNZT


Asunto(s)
Estadísticas no Paramétricas , Interacciones Hidrofóbicas e Hidrofílicas , Propiedades de Superficie , Streptococcus mutans , Titanio , Topografía
6.
Braz. oral res ; 26(6): 505-510, Nov.-Dec. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-656695

RESUMEN

Incorporation of silver nanoparticles into composite resins is recommended for their reported antibacterial properties, but this incorporation can affect the wettability of such materials. Therefore, this study evaluated the effect of nano-silver addition to silorane-based and methacrylate-based composites on their contact angle. Nano-silver particles were added to Z250 (methacrylate-based) and P90 (silorane-based) composites at 0.5% and 1% by weight. The control group had no additions. SEM-EDX analysis was performed to confirm the homogeneity of the nano-silver distribution. Seventy-two composite discs were prepared and standardized to the identical surface roughness values, and then distributed randomly into 6 groups containing 12 samples each (N = 12). Two random samples from each group were observed by atomic force microscopy. Distilled water contact angle measurements were performed for the wettability measurement. Two-way ANOVA, followed by the Tukey-HSD test, with a significance level of 5%, were used for data analysis. It was observed that wettability was significantly different between the composites (p = 0.0001), and that the addition of nano-silver caused a significant reduction in the contact angle (p = 0.0001). Wettability varied depending on the concentration of the nano silver (p = 0.008). Silorane-based composites have a higher contact angle than methacrylate-based composites. Within the limitations of this study, it can be concluded that the addition of 0.5% nano-silver particles to the composites caused a decrease in the contact angle of water.


Asunto(s)
Humanos , Resinas Compuestas/química , Nanopartículas del Metal/química , Metacrilatos/química , Resinas de Silorano/química , Plata/química , Análisis de Varianza , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Humectabilidad
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