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1.
Odovtos (En línea) ; 26(2): 101-112, May.-Aug. 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1575329

ABSTRACT

Abstract The aim of the present study was to analyze the effects of 4 different surface treatments, on the crystallographic characteristics of Ultra-Translucent Zirconia. Fully sintered zirconia specimens of highly translucent yttria partially stabilized zirconia (Y-PSZ) (KATANA UTML) were divided into four experimental groups and a control group (n=10). Each group received one of the following surface treatments: sandblasting with 50µm alumina particles sandblasting with 110µm alumina particles, and grinding with a rotary high-speed turbine with and without water irrigation. For each sample, x-ray diffraction was carried out to analyze peak intensity, calculate the crystallite size, and detect the presence of compressive and tensile stress. Surface roughness was measured on all specimens using a standard scanning profilometer. Additionally, scanning electron microscopy (SEM) was performed to qualitatively analyze the surfaces of the specimens. Statistical analysis included repeated measures analysis of variance and post hoc Tukey test (p≤0.05). The control group exhibited the highest crystallite size (323nm). All surface treatments led to a reduction in the crystallite size, with the most significant reduction observed in the groups subjected to sandblasting with 110µm alumina particles and high- speed grinding with irrigation. Sandblasting with 50µm alumina particles resulted in less transformation of the crystallite size. A general tendency of the diffraction peaks to shift to a lower angle can be observed in the experimental groups, indicating the presence of compressive stress on the samples. Profilometry revealed higher roughness in the ground samples (6,14µm and 6,57µm) compared to the sandblasted groups (2,93µm and 2,02µm). The crystal domain size showed a tendency to decrease after the surface treatments. Sandblasted samples, as well as ground samples without irrigation, exhibited compressive stress. Sandblasted samples had lower surface roughness compared to the ground samples. Sandblasting with 50µm alumina particles caused the least decrease in crystallite size.


Resumen El objetivo del presente estudio fue analizar los efectos de 4 tratamientos de superficie en las características cristalográficas de la zirconia ultratranslúcida. Especímenes de zirconia totalmente sinterizados, altamente translúcidos de zirconia parcialmente estabilizada con itrio (Y-PSZ) (KATANA UTML) se dividieron en cuatro grupos experimentales y un grupo de control (n=10). Cada grupo recibió uno de los siguientes tratamientos de superficie: arenado con partículas de alúmina de 50µm (Al2O3), arenado con partículas de alúmina de 110µm y desgaste con una turbina rotativa de alta velocidad con y sin irrigación. Para cada muestra, se llevó a cabo una difracción de rayos X para analizar la intensidad del pico, calcular el tamaño del cristalito y detectar la presencia de tensiones compresivas y tensiles. La rugosidad superficial se midió en todos los especímenes utilizando un perfilómetro estándar. Además, se realizó microscopía electrónica de barrido (SEM) para analizar cualitativamente las superficies de los especímenes. El análisis estadístico incluyó un análisis de varianza de medidas repetidas y una prueba de Tukey post hoc (p≤0,05). El grupo de control mostró el tamaño de cristalito más alto (323nm). Todos los tratamientos de superficie llevaron a una reducción en el tamaño del cristalito, con la reducción más significativa observada en los grupos sometidos a arenado con partículas de alúmina de 110µm y desgaste de alta velocidad con irrigación. El arenado con partículas de alúmina de 50µm resultó en una menor transformación del tamaño del cristalito. Se puede observar una tendencia general de los picos de difracción a desplazarse a un ángulo más bajo en los grupos experimentales, lo que indica la presencia de estrés compresivo en las muestras. La perfilometría reveló una mayor rugosidad en las muestras con desgaste con instrumento rotatorio (en comparación con los grupos arenados. El tamaño del cristalito mostró una tendencia a disminuir después de los tratamientos de superficie. Las muestras arenadas, así como las muestras desgastadas sin irrigación, mostraron estrés compresivo. Las muestras arenadas tuvieron una menor rugosidad superficial en comparación con las muestras desgastadas con rotatorio. El arenado con partículas de alúmina de 50µm provocó la menor disminución en el tamaño del cristalito.

2.
Braz. dent. j ; Braz. dent. j;35: e24, 2024. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1550097

ABSTRACT

Abstract This study verified the effect of surface treatments of the zirconia-reinforced lithium disilicate ceramic bonded to resin cement. Ceramic blocks were divided according to treatments (n=10): FA+SRX (Fluoric acid + silane RX), FA+MDP (Fluoric acid + MDP), FA+SCF+MDP (Fluoric acid + silane CF + MDP), FA+MEP (Fluoric acid + MEP), and MEP (Self-etch primer). Resin cement cylinders were made in the ceramic blocks, photoactivated with 1,200 mW/cm² for 40s, stored in water at 37°C for 24h, and evaluated by the microshear strength test, optical failure descriptive analysis (%), surface characterization (SEM) and contact angle (Goniometer). Other samples were submitted to 10,000 thermocycles between 5°C and 55°C. Bond strength data were submitted to two-way ANOVA and Tukey's test. Contact angle to one-way ANOVA and Games-Howell's test (5%). At 24h, MEP showed higher bond strength, and FA+SRX the lower. FA+MDP and FA+SCF+MDP showed similar values and FA+MEP was intermediate. After thermocycling, FA+SCF+MDP, FA+MEP, and MEP showed higher values, and FA+SRX the lower while FA+MDP was intermediate. When the periods were compared, FA+MDP, FA+SCF+MDP, FA+MEP, and MEP showed higher values for 24h while FA+SRX was similar. SEM showed retentive surface and crystal exposure when treated with FA+SCF+MDP. The less retentive surface was obtained with MEP, and the other treatments promoted intermediate irregularities. In conclusion, surface treatment and thermocycling promoted different values of adhesive strength and contact angle in a zirconia-reinforced lithium silicate ceramic. Failures were predominantly adhesive, and the ceramic surface was characterized by different levels of roughness and selective exposure of crystals.


Resumo O objetivo neste estudo foi verificar o efeito de tratamentos de superfície da cerâmica de dissilicato de lítio reforçada com zircônia fixada ao cimento resinoso. Os blocos cerâmicos foram separados de acordo com os tratamentos (n=10): AF+SRX (ácido fluorídrico + silano), AF+MDP (ácido fluorídrico + MDP), AF+SCF+MDP (ácido fluorídrico + silano + MDP), AF+MEP (Ácido fluorídrico + MEP) e MEP (Primer auto condicionante). Cilindros de cimento resinoso foram confeccionados em cada bloco cerâmico, foto ativados com 1.200 mW/cm² por 40 segundos, armazenados em água a 37°C por 24 horas e avaliados pelo teste de resistência ao micro cisalhamento, falha por análise descritiva em microscopia óptica (%), caracterização da superfície por imagens MEV e ângulo de contato (Goniômetro). Outras amostras foram submetidas a 10.000 ciclos térmicos (5° e 55°C). Os dados de resistência de união foram submetidos a ANOVA dois fatores e teste de Tukey (5%). Ângulo de contato com ANOVA um fator e teste de Games-Howell (5%). Em 24 horas, MEP apresentou maior resistência de união e AF+S a menor. AF+MDP e AF+SCF+MDP apresentaram valores similares e AF+MEP foi intermediário. Após a ciclagem térmica, AF+SCF+MDP, AF+MEP e MEP apresentaram valores maiores e AF+SRX o menor enquanto AF+MDP foi intermediário. Quando comparados os períodos, AF+MDP, AF+SCF+MDP, AF+MEP e MEP apresentaram valores maiores em 24 horas enquanto AF+SRX foi similar. MEV mostrou superfície mais retentiva e exposição de cristais quando tratada com AF+SCF+MDP. A superfície menos retentiva foi obtida com MEP, e os demais tratamentos promoveram irregularidades de superfície intermediárias. Conclui-se que o tratamento superficial e a termociclagem promoveram diferentes valores de resistência adesiva e ângulo de contato em cerâmica de silicato de lítio reforçada com zircônia. As falhas foram predominantemente adesivas, e a superfície cerâmica foi caracterizada com diferentes níveis de rugosidade e exposição seletiva de cristais.

3.
Braz. dent. j ; Braz. dent. j;35: e24, 2024. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1581809

ABSTRACT

Abstract: This investigation demonstrates the effect of alkali modification of titanium on the metabolism of human osteoblasts. Polished titanium discs were subjected to alkalinization protocols with NaOH (5M) at 60°C or 120°C. Surface topography and roughness were evaluated using scanning electron microscopy (SEM). Osteoblasts were seeded onto titanium discs, followed by cell adhesion and viability analysis, total protein and collagen production, and alkaline phosphatase (ALP) activity. Gene expression of tumor necrosis factor-alpha (TNF-α) and beta-defensin 3 (HBD3) was evaluated after inflammatory stimulus with lipopolysaccharides (LPS) of Porphyromonas gingivalis (1 μg/mL) for 4 h. Discs subjected to modification with NaOH showed major irregularities, especially for 120°C-protocol. Increased adhered cell number was observed for surfaces modified by NaOH. Osteoblasts cultured on modified surfaces showed higher cell viability, total protein and collagen synthesis, and ALP activity than that of cells cultured on the polished discs. Osteoblast response to LPS exposure showed increased TNF-α gene expression by these cells when cultured on the polished discs, while increased expression of HBD3 was detected for all groups in the presence of LPS. Modification of titanium discs by NaOH at 60°C or 120°C promoted an increase in adhesion and metabolism of osteoblasts and favored the response to inflammatory stimulus.


Resumo Este estudo demonstra o efeito da modificação da superfície de titânio por alcalinização sobre o metabolismo de osteoblastos humanos. Discos de titânio polidos foram submetidos ao protocolo de alcalinização com NaOH (5M) a 60°C ou 120°C. A topografia e rugosidade superficial foram avaliados por microscopia eletrônica de varredura (MEV). Osteoblastos foram cultivados sobre discos de titânio, seguido de análise da adesão e viabilidade celular, síntese de proteína total e colágeno, além de atividade de fosfatase alcalina (ALP). A expressão genica do fator de necrose tumoral-alfa (TNF-α) e beta-defensina (HBD-3) foram avaliadas após estimulo inflamatório com lipopolissacarídeos (LPS) de Porphyromonas gingivalis (1 μg/mL) por 4 h. Os discos submetidos à modificação com NaOH demonstraram maiores irregularidades, especialmente para o protocolo de 120°C. Aumento da adesão celular foi observada para as superfícies modificadas por NaOH. Os osteoblastos cultivados sobre as superfícies modificadas apresentaram maior viabilidade, síntese de proteína total e de colágeno, além de maior atividade de ALP quando comparadas às células cultivadas sobre os discos polidos. Os osteoblastos apresentaram aumento da síntese de TNF-α em resposta ao LPS para as células cultivadas sobre os discos polidos, enquanto aumento da expressão de HBD-3 foi detectado para todos os grupos na presença de LPS. A modificação dos discos de titânio por NaOH a 60°C ou 120°C promoveu aumento da adesão e metabolismo de osteoblastos e favoreceu a resposta a estímulo inflamatório.

4.
Braz. dent. j ; Braz. dent. j;35: e24, 2024. tab, graf
Article in Portuguese | LILACS-Express | LILACS, BBO | ID: biblio-1581831

ABSTRACT

Resumo Este estudo in vitro teve como objetivo investigar o efeito da nitretação por implantação iônica de plasma nas propriedades de superfície do titânio e na resposta celular inicial. Discos de titânio grau 4 (12,7 × 2 mm) foram jateados com partículas de óxido de alumínio para criar superfícies moderadamente rugosas. Os discos experimentais (TiN) foram nitrados usando a técnica de implantação iônica de plasma em uma câmara de vácuo. A caracterização da superfície foi realizada usando microscopia confocal a laser, microscopia de força atômica (AFM) e espectroscopia de fotoelétrons de raios X (XPS). A molhabilidade da superfície foi avaliada medindo o ângulo de contato de uma gota séssil usando um goniômetro. Células osteoblásticas humanas foram semeadas nos discos para avaliar a adesão e proliferação celular nos dias 1, 3, 5 e 7 de cultura, usando um ensaio de composto de tetrazólio. A atividade da fosfatase alcalina (ALP) foi medida no dia 7 para avaliar a diferenciação celular. A morfologia celular foi examinada por microscopia eletrônica de varredura (SEM) e microscopia confocal a laser. O grupo TiN exibiu micro-rugosidade similar ao grupo controle; no entanto, apresentou maior densidade de nanostruturas, aumento do conteúdo de nitrogênio e ligeira melhoria na molhabilidade. A proliferação celular e a atividade da ALP foram similares entre os grupos após sete dias de cultura. Em conclusão, a nitretação por implantação iônica de plasma melhora as nanocaracterísticas da superfície e a molhabilidade sem comprometer a biocompatibilidade do titânio, tornando-se uma técnica promissora de modificação de superfície para implantes dentários e ortopédicos.


Abstract This in vitro study aimed to investigate the effect of plasma ion implantation nitriding on titanium's surface properties and initial cell response. Grade 4 titanium discs (12.7 × 2 mm) were blasted with aluminum oxide particles to create moderately rough surfaces. The experimental discs (TiN) were nitrided using the plasma ion implantation technique in a vacuum chamber. Surface characterization was performed using laser confocal microscopy, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). Surface wettability was assessed by measuring the contact angle of a sessile drop using a goniometer. Human osteoblast cells were seeded on the discs to evaluate cell attachment and proliferation at 1, 3, 5, and 7 days of culture using a tetrazolium compound assay. Alkaline phosphatase (ALP) activity was measured at day 7 to assess cell differentiation. Cell morphology was examined by scanning electron microscopy (SEM) and confocal laser scanning microscopy. The TiN group exhibited similar micro-roughness to the control group; however, it displayed a higher density of nanostructures, increased nitrogen content, and slightly improved wettability. Cell proliferation and ALP activity were similar between the groups after seven days of culture. In conclusion, plasma ion implantation nitriding enhances surface nanofeatures and wettability without compromising the biocompatibility of titanium, making it a promising surface modification technique for dental and orthopedic implants.

5.
Article | IMSEAR | ID: sea-235317

ABSTRACT

Introduction: Successful post retention within the root canal is a prerequisite in the post endodontic restoration of a structurallycompromised tooth. Apart from the formation of surface roughness on the glass fiber post (GFP), the surface treatment strategiesshould generate a strong chemical bond of the exposed epoxy resin matrix in the post with the root dentin through a resin cement.Purpose: To compare the influence of different surface treatments on the push-out bond strength (PBS) of GFPs to root dentinand to determine the modes of failure between root dentin, resin luting cement, and the post surface.Methods: Sixty extracted mandibular premolars were divided into six groups (n = 10). Rotary instrumentation followed byobturation was done with a single cone technique. Sixty GFPs (6 groups; n = 10) were treated with one of the following: Nosurface treatment, Silane coupling agent, Bonding agent, Sandblasting, 9.6% Hydrofluoric acid, and 100 mL alkaline solutionof Potassium permanganate. Treated posts were luted to the prepared post space using self-adhesive resin cement. Coronal,middle, and apical portions obtained after sectioning the roots embedded in resin mold were subjected to a PBS test, andthe “peak force” at bond failure was measured. The modes of failure between the interfaces were assessed using ScanningElectron Microscopy. Statistical analysis was performed using the Kruskal–Wallis test and Bonferroni multiple comparison test.Results: Group III (Bonding) and Group IV (Sandblasting) showed the highest bond strength in the coronal and apical sections.Conclusion: The surface treatment of GFPs using either a universal adhesive or sandblasting was reliable. PBS for coronal andapical root sections was superior to the middle sections. A mixed mode of failure was predominant among tested specimens.

6.
Article | IMSEAR | ID: sea-239429

ABSTRACT

Surface treatment is a crucial process in the medical device industry that plays a vital role in improving the performance, durability, and safety of medical devices. This article provides an overview of the importance of surface treatment in the medical device industry. The article discusses the various surface treatment processes such as cleaning, passivation, anodizing, coating, plasma treatment, ion implantation, and surface roughening, and how they can improve the biocompatibility, corrosion resistance, adhesion, lubricity, and sterilization properties of medical devices. The article emphasizes the significance of biocompatibility in medical devices and how surface treatment processes can improve it. The article also highlights the importance of corrosion resistance and how surface treatment processes can provide the necessary protection. Additionally, the article discusses how surface treatment processes can improve the adhesion properties of medical devices, making them more effective in surgical procedures. Finally, the article concludes by summarizing the critical role of surface treatment in the medical device industry and how it contributes to enhancing the performance and safety of medical devices.

7.
Beijing Da Xue Xue Bao ; (6): 94-100, 2023.
Article in Chinese | WPRIM | ID: wpr-971279

ABSTRACT

OBJECTIVE@#To study microstructure, friction and wear behaviors of silicon-lithium spray coating on the surface of zirconia ceramics and to preliminarily evaluate its esthetic so as to provide support and guidance for the clinical application.@*METHODS@#Zirconia ceramic specimens were randomly divided into three groups: coating group (two subgroups), polishing group (two subgroups), and glazing group (four subgroups), with 10 samples in each subgroup. The two subgroups of coating group were the zirconia ceramics with the untreated and preliminary polishing surfaces sprayed with silicon-lithium coating, respectively. The two subgroups of polishing group were preliminary polishing and fine polishing of zirconia ceramics, respectively. The four subgroups of glazing group were preliminarily polished zirconia ceramics glazed with Biomic and Stain/Glaze products, respectively; and untreated zirconia ceramics glazed with Biomic and Stain/Glaze products, respectively. The above 8 subgroups of zirconia ceramic specimens were used as friction pairs with 80 steatite ceramics for 50 000 chewing cycles under 50 N vertical load and artificial saliva lubrication using chewing simulation. Scanning electron microscope was used to observe the microstructure of the surface and section of the coating group, and the thickness of the coating and glazing were measured. The linear roughness of the coating and polishing groups was mea-sured using a laser confocal scanning microscope. Vickers hardness was measured using a microhardness tester and the esthetic of zirconia ceramic full crown sprayed with silicon-lithium coating was preliminarily evaluated. White light interferometer was used to measure the width, the maximum depth and the volume of the wear scars of each group, and the wear depth of steatite ceramics and wear rate of zirconia ceramic specimens were calculated. Kruskal-Wallis nonparametric test and Dunn's multiple comparisons test were used to analyze the wear depth of each group (α=0.05).@*RESULTS@#The microstructures of the silica-lithium spray coatings on the untreated and preliminarily polished zirconia ceramic surfaces showed the protruding defects, and the line roughness of coating group was larger than that of the polishing group. The median thickness of the silica-lithium spray coating on the preliminarily polished zirconia ceramic was 13.0 μm (interquartile range, IQR: 11.6, 17.9), while that of the silica-lithium spray coating on the untreated zirconia ceramic was 4.4 μm (IQR: 4.1, 4.7). The Vickers hardness and wear rate of the coating group were between the polishing group and the glazing group. The wear depths of the wear scars of steatite ceramics were the glazing group, coating group, and polishing group in descending order, and there was statistically significant difference between glazing and polishing groups (P < 0.05). With the increase of polishing procedure, the wear depth of steatite ceramics decreased in each subgroups. The orders of maximum depth and volume of wear scars of zirconia ceramic were the glazing group, coating group, and polishing group in descending order, and there was statistically significant difference in the maximum depth of wear scars between glazing and polishing groups (P < 0.05).@*CONCLUSION@#The silica-lithium spray coating on the zirconia ceramic, can be used as a new method for zirconia ceramic surface treatment, because it can increase the esthetic of zirconia ceramics compared with polishing and reduce the wear of steatite ceramics compared with glazing.


Subject(s)
Humans , Silicon , Materials Testing , Friction , Lithium , Cicatrix , Surface Properties , Silicon Dioxide , Zirconium/chemistry , Ceramics , Dental Porcelain
8.
Article in Chinese | WPRIM | ID: wpr-972198

ABSTRACT

Objective @# To investigate the effect of micro/nano hierarchical structures on the adhesion and proliferation of MC3T3-E1 cells, evaluate the drug delivery potential of titanium surfaces, and provide a reference for the modification of selected areas of titanium surfaces to enhance drug delivery and slow drug release. @*Methods @# Pure titanium samples (10 mm in diameter and 2.5 mm in thickness) were randomly divided into a polished group (T), anodized group (TO), and micro/nano hierarchical structure group (FTO) according to the surface treatment of the titanium. The T group was polished, the TO group was treated with anodic oxidation technology, and the FTO group was treated by femtosecond laser etching combined with anodic oxidation technology. The three surface morphologies were observed by scanning electron microscopy (SEM), the wettability of the surface was measured by the contact angle, and the surface chemical composition was analyzed by X-ray energy dispersive spectroscopy (EDS). The depth of the FTO structure and the surface roughness were measured by confocal laser scanning microscopy (CLSM). MC3T3-E1 cell adhesion proliferation and differentiation on the surface of each group of samples was assessed by immunofluorescence staining, CCK-8, and semiquantitative analysis of Alizarin staining. A freeze-drying method was applied to load recombinant human bone morphogenetic protein-2 (rhBMP-2), and an enzyme-linked immunosorbent assay (ELISA) was used to assess the drug-loading potential of different surface structures. @* Results@#SEM revealed that the surface of T group titanium plates showed uniform polishing marks in the same direction. The surface of the TO group was a nanoscale honeycomb-like titanium dioxide (TiO2) nanotube structure, and the FTO group formed a regular and ordered micro/nano layered structure. The contact angle of the FTO group was the smallest at 32° ± 1.7°. Its wettability was the best. The average depth of the first-level structure circular pores was 93.6 μm, and the roughness was 1.5-2 μm. The TO and FTO groups contained a high percentage of oxygen, suggesting TiO2 nanotube formation. The FTO group had the most significant surface cell proliferation (P<0.001) and the largest cell adhesion surface area (P<0.05). rhBMP-2 was slowly released for 14 d after loading in the FTO group and promoted extracellular matrix mineralization (P<0.001). @*Conclusion @#Titanium surface microprepared hierarchical structure has the effect of promoting MC3T3-E1 cell adhesion, proliferation, and osteogenic differentiation with drug loading potential, which is a new method of titanium surface treatment.

9.
São José dos Campos; s.n; 2023. 94 p. ilus, tab.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1444122

ABSTRACT

Apesar da confiabilidade, as falhas mecânicas e biológicas das reabilitações protéticas sobre implantes ainda são persistentes. A capacidade altamente adaptativa das bactérias e sua colonização na superfície dos implantes e componentes protéticos ainda hoje é um sério problema clínico, causando mucosite e peri-implantite. O objetivo do trabalho foi avaliar o efeito antimicrobiano do fino filmes de carbono tipo diamante (DLC) dopado com nanopartículas de prata, depositado nos parafusos protéticos. Os filmes de DLC e DLC-Ag foram depositados pelo processo conhecido como PECVD (Plasma Enhanced Chemical Vapour Deposition). A caracterização do material foi realizada em discos da liga Ti6Al4V pelas análises scratch test, espectroscopia de espalhamento Raman, perfilometria mecânica, goniometria e espectroscopia de energia dispersiva (EDS). A atividade antimicrobiana foi avaliada utilizando uma cepa padrão de Enterococcus faecalis (ATCC 29212). Para avaliar a efetividade dos filmes depositados, foram realizados ensaios nos discos e nos parafusos (isolados e no modelo implante/pilar). Foram utilizados implantes hexágono externo de plataforma regular 4,1 mm com os respectivos pilares. Para todas as análises, as amostras foram divididas em 3 grupos de acordo com o tipo de tratamento: Grupo controle (sem tratamento); Grupo DLC, amostras revestidas com filme de DLC, Grupo DLC-Ag, amostras revestidas com filme de DLC com prata. As amostras foram analisadas por MEV. Também foi avaliada a citotoxicidade dos filmes frente a células de fibroblastos (3T3) através do ensaio de MTT. A caracterização dos filmes por espectroscopia de espalhamento raman e EDS, apresentaram resultados característicos ao DLC e DLC-Ag, como uma distribuição homogênea de carbono, prata e silício. As análises de scratch test, perfilometria mecânica e goniometria, apresentaram filmes com características hidrofóbicas, sendo DLC-Ag o grupo de maior rugosidade e coeficiente de atrito. Os dados obtidos foram analisados estatisticamente com auxílio do programa GraphPad Prism versão 9.0 (GraphPad Software Inc., San Diego, CA, USA) e realizado os testes ANOVA e de Tukey para comparações entre os grupos (discos), e os testes Kruskal-Wallis e post-hoc de Dunn (parafusos). O nível de significância para todos os testes foi estabelecido em 5%. Os resultados demonstraram que a deposição do filme de DLC e DLC-Ag apresentaram redução de maneira significativa (p<0,05) na contagem de UFC/ml nos discos e parafusos isolados. Porém a dopagem com prata não trouxe um resultado superior ao filme DLC e ambos os materiais se apresentaram como não citotóxico. Concluímos que o revestimento com DLC e DLC-Ag é um material promissor, com efeito antimicrobiano, porém com limitação de aplicação (AU)


Despite the reliability, the mechanical and biological failures in rehabilitating implantsupported dental are still persistent. Mucositis and peri-implantitis are still severe clinical problems due to the high adaptive capacity of bacteria that colonize the surface of implants and prosthetic components. The present study aimed to evaluate, in vitro, the antimicrobial action of thin films of diamond-like carbon (DLC) doped with silver nanoparticles, deposited on prosthetic screws. The deposition of the films was performed by PECVD (Plasma Enhanced Chemical Vapor Deposition). The characterizations were performed of both deposited samples and control (Ti6Al4V) by scratch test analysis, raman scattering spectroscopy, mechanical profilometry, goniometry, and energy dispersive spectroscopy (EDS). The antimicrobial was evaluated activity against Enterococcus faecalis (ATCC 29212). To evaluate the effectiveness of the deposited films, tests were performed on disks and screws (isolated and on the implant/abutment model) Using 30 regular platforms with 4.1 mm external hexagon implants with the respective abutments, distributed into 3 groups according to the type of prosthetic screw treatment (n=10): Group control screw (no treatment); Group screw coated with DLC film, Group screw coated with DLC film doped with silver nanoparticles (Ag-DLC). The samples were also analyzed by SEM The cytotoxicity of the films against (3T3) fibroblast cells was also assessed using the MTT assay. The caracterization was performed from raman spectroscopy and EDS, showed results which are characteristics of DLC and Ag-DLC films, such as a homogeneous distribution of carbon, silver and silicon. The scratch test, mechanical profilometry and goniometry analyzes showed films with hydrophobic characteristics, with Ag-DLC being the group with the higher coefficient of friction values and roughness Data were statistically analyzed using GraphPad Prism version 9.0 (GraphPad Software Inc., San Diego, CA, USA). ANOVA and Tukey tests were performed, followed by comparisons between groups (disks) and Kruskal-Walis and post-hoc Dunn (screw) tests The significance level for all tests was set at 5%. The results demonstrated that the deposition of the DLC and Ag-DLC film showed a significant reduction (p<0.05) in the CFU/ml count compared to the contro, disks and isolated screwl. However, silver doping did not enhance the DLC films; both materials were non-cytotoxic. It concludes that titanium alloys coated with DLC and Ag-DLC are promising materials with antibacterial properties to prevent peri-implantitis (AU)


Subject(s)
Dental Implants , Enterococcus faecalis
10.
Braz. dent. sci ; 26(3): 1-13, 2023. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1437871

ABSTRACT

Objective: to evaluate the effect of novel zirconia surface treatment method on shear bond strength between zirconia and veneering porcelain compared to air abrasion and CoJet surface treatment methods. Material and Methods: twenty-one zirconia ceramic discs were fabricated with diameter of 7mm and 3mm thickness and divided according to surface treatment into three subgroups, control group I: Air Abrasion (n=7), group II: CoJet (n=7) and group III: Z-etch (n=7). Porcelain was built over the zirconia specimens with a customized mold and fired in a ceramic furnace. All specimens were thermocycled (20000 cycles) between 5°C ­ 55 °C with a dwell time of 30 seconds in distilled water and shear bond strength of veneering porcelain to each zirconia specimen was tested using a universal testing machine. Results: numerical data were explored for normality by checking the distribution of data and using tests of normality (Kolmogorov-Smirnov and Shapiro-Wilk tests). One-way ANOVA test was used to compare between the groups. There was a statistically significant difference between the three groups (P-value = 0.002, Effect size = 0.503). Pair-wise comparisons between groups revealed that Z-etch showed the statistically significantly highest mean shear bond strength. Conclusion: zirconia coating using z-etch is showing promising results in promoting higher bond strength than conventional surface treatment methods as air abrasion and silica coating (AU)


Objetivo: avaliar o efeito do novo método de tratamento de superfície de zircônia na resistência ao cisalhamento entre a zircônia e a porcelana de cobertura em comparação com os métodos de abrasão a ar e jateamento com CoJet. Material e Métodos: vinte e um discos de zircônia foram confeccionados com diâmetro de 7mm e espessura de 3mm e divididos de acordo com o tratamento de superfície em três subgrupos, grupo controle I: Abrasão a ar (n=7), grupo II: CoJet (n=7) e grupo III: Z-etch (n=7). A porcelana foi aplicada sobre os espécimes de zircônia com um molde personalizado e sinterizada em forno de cerâmica. Todos os espécimes foram termociclados (20.000 ciclos) entre 5°C - 55°C com um tempo de permanência de 30 segundos em água destilada e a resistência ao cisalhamento da porcelana de cobertura foi testada através de uma máquina de ensaio universal. Resultados: os dados numéricos foram avaliados quanto à normalidade, verificando a distribuição dos dados e utilizando testes de normalidade (testes de Kolmogorov-Smirnov e Shapiro-Wilk). O teste ANOVA de um fator foi utilizado para comparar os grupos. Houve uma diferença estatisticamente significativa entre os três grupos (P-valor = 0,002, tamanho do efeito = 0,503). As comparações pareadas entre os grupos revelaram que o Z-etch apresentou a resistência de união ao cisalhamento estatisticamente significativamente mais alta. Conclusão: o revestimento de zircônia utilizando Z-etch mostrou resultados promissores para o aumento da resistência de união em comparação aos métodos convencionais de tratamento de superfície, como abrasão a ar e revestimento de sílica (AU)


Subject(s)
Air Abrasion, Dental , Shear Strength , Dental Materials
11.
Dental press j. orthod. (Impr.) ; 28(2): e2321345, 2023. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1439988

ABSTRACT

ABSTRACT Objectives: This clinical trial was conducted to evaluate the stability and failure rate of surface-treated orthodontic mini-implants and determine whether they differ from those of non-surface-treated orthodontic mini-implants. Trial Design: Randomized clinical trial with a split-mouth study design. Setting: Department of Orthodontics, SRM Dental College, Chennai. Participants: Patients who required orthodontic mini-implants for anterior retraction in both arches. Methods: Self-drilling, tapered, titanium orthodontic mini-implants with and without surface treatment were placed in each patient following a split-mouth design. The maximum insertion and removal torques were measured for each implant using a digital torque driver. The failure rates were calculated for each type of mini-implant. Results: The mean maximum insertion torque was 17.9 ± 5.6 Ncm for surface-treated mini-implants and 16.4 ± 9.0 Ncm for non-surface-treated mini-implants. The mean maximum removal torque was 8.1 ± 2.9 Ncm for surface-treated mini-implants and 3.3 ± 1.9 Ncm for non-surface-treated mini-implants. Among the failed implants, 71.4% were non-surface-treated mini-implants and 28.6% were surface-treated mini-implants. Conclusion: The insertion torque and failure rate did not differ significantly between the groups, whereas the removal torque was significantly higher in the surface-treated group. Thus, surface treatment using sandblasting and acid etching may improve the secondary stability of self-drilling orthodontic mini-implants. Trial registration: The trial was registered in the Clinical Trials Registry, India (ICMR NIMS). Registration number: CTRI/2019/10/021718


RESUMO Objetivos: Este ensaio clínico foi conduzido para avaliar a estabilidade e a taxa de falha de mini-implantes ortodônticos com superfície tratada, e determinar se elas diferem das dos mini-implantes ortodônticos sem superfície tratada. Desenho do estudo: Ensaio clínico randomizado com desenho de boca dividida. Instituição: Department of Orthodontics, SRM Dental College, Chennai/India. Participantes: Pacientes que necessitavam de mini-implantes ortodônticos para retração anterior em ambas as arcadas. Métodos: Mini-implantes ortodônticos autoperfurantes, cônicos, de titânio com ou sem tratamento de superfície, foram colocados em cada paciente, seguindo um desenho de boca dividida. Os torques máximos de inserção e de remoção foram medidos para cada mini-implante, usando um torquímetro digital. As taxas de falha foram calculadas para cada tipo de mini-implante. Resultados: O valor médio do torque máximo de inserção foi de 17,9 ± 5,6 Ncm para mini-implantes com superfície tratada e 16,4 ± 9,0 Ncm para mini-implantes sem superfície tratada. O valor médio do torque máximo de remoção foi de 8,1 ± 2,9 Ncm para mini-implantes com superfície tratada e 3,3 ± 1,9 Ncm para mini-implantes sem superfície tratada. Entre os implantes que falharam, 71,4% eram mini-implantes sem superfície tratada e 28,6% eram mini-implantes com superfície tratada. Conclusão: O torque de inserção e a taxa de falha não diferiram significativamente entre os grupos; porém, o torque de remoção foi significativamente maior no grupo com superfície tratada. Assim, o tratamento de superfície com jateamento e condicionamento ácido pode melhorar a estabilidade secundária dos mini-implantes ortodônticos autoperfurantes. Registro do estudo: Esse estudo foi registrado no Clinical Trials Registry, Índia (ICMR NIMS). Número de registro: CTRI/2019/10/021718

12.
Int. j interdiscip. dent. (Print) ; 15(3): 233-239, dic. 2022. tab
Article in Spanish | LILACS | ID: biblio-1421731

ABSTRACT

Resumen: Los microtornillos de ortodoncia corresponden a dispositivos de anclaje temporal que sirven como coadyuvantes en el tratamiento ortodóncico y cuyo uso se ha ido incrementando en el último tiempo. Las fallas de los microtornillos tienden a ocurrir durante la primera semana de inserción por lo que mejorar la estabilidad es un paso importante para mejorar la confiabilidad del tratamiento. Una posible solución a esto es modificar la superficie del microtornillo. Objetivo: Identificar en la literatura actual los tratamientos de superficie más utilizados que favorezcan la estabilidad primaria y secundaria en el éxito de los microtornillos en ortodoncia. Material y método: Se realizó una búsqueda en Pubmed y EBSCO con los términos en idioma inglés "miniscrew"/"mini implant" AND "surface", "treatment" and "stability". Se incluyeron los estudios realizados in vivo con el objetivo de comparar y/o evaluar el efecto de los tratamientos realizados en la superficie del microtornillo en el éxito o estabilidad de éste, artículos disponibles en inglés y español. Se excluyeron estudios realizados en implantes dentales y/o médicos, in vitro, estudios clínicos sin grupo control. Resultados: 25 publicaciones fueron utilizadas en la revisión, habiendo 11 tipos de tratamiento de superficie estudiados. La generación de ma trices de nanotubos de óxido de titanio, fotofuncionalización mediada por rayos ultravioleta y anodizado de superficie evidenciaron aumento de la estabilidad de los microtornillos. El uso de técnicas convencionales: grabado ácido, arenado-grabado ácido, no es concluyente en cuanto a su efecto en la estabilidad. Conclusión: Hay escasa evidencia sobre los tratamientos de superficie realizados en microtornillos de ortodoncia para la mejora de su estabilidad. Técnicas pioneras como la generación de matrices de nanotubos de óxido de titanio, fotofuncionalización mediada por rayos ultravioleta y anodizado de superficie evidenciaron aumento de la estabilidad de los microtornillos, siendo necesaria la replicación de los estudios en humanos. La utilización de técnicas convencionales tales como grabado ácido y arenado-grabado ácido, no es concluyente en cuanto a su efecto en la estabilidad de los microtornillos.


Abstract: Orthodontic miniscrews are temporary anchoring devices that help as adjuvants in orthodontic treatment and whose use has increased in recent times. Miniscrew failures can happen during the first week of insertion, so improving stability is an important step to enhance treatment reliability. A possible solution to this issue is to modify the miniscrew surface. Objective: To identify in the current literature the most widely used surface treatments that favor the primary and secondary stability and success of orthodontic miniscrews. Material and method: A search was made in Pubmed and EBSCO with the English terms "miniscrew"/"mini implant" AND "surface", "treatment" and "stability". In vivo studies were included with the aim of comparing and/or evaluating the effect of the treatments performed on the miniscrew's surface and their success or stability, articles available in English and Spanish. Studies performed in dental and/or medical implants, in vitro, clinical studies without control group were excluded. Results: 25 publications were used in the review, with 11 types of surface treatment studied. The generation of titanium oxide nanotube matrices, ultraviolet-mediated photofunctionalization and surface anodizing showed an increase in the stability of the miniscrews. The use of conventional techniques: acid etching, sandblasting-acid etching, is inconclusive as to its effect on stability. Conclusion: There is little evidence of surface treatments performed on orthodontic miniscrews to improve their stability. Pioneering techniques such as the generation of titanium oxide nanotube matrices, ultraviolet-mediated photofunctionalization and surface anodizing showed increased stability of the miniscrews, and require their replication on human studies. The use of conventional techniques such as acid etching and acid sandblasting-etching is inconclusive as to its effect on the stability of the miniscrews.


Subject(s)
Humans , Orthodontics, Corrective/methods , Bone Screws , Denture Retention , Orthodontic Anchorage Procedures
13.
Int. j. odontostomatol. (Print) ; 16(3): 343-349, sept. 2022. tab
Article in English | LILACS | ID: biblio-1405312

ABSTRACT

ABSTRACT: The objective of this in vitro study was to evaluate the effects of finishing protocols and oral hygiene procedures on the surface and mechanical properties of CAD/CAM ceramics. Specimens (n = 96, (15x10x2mm) of the leucite glass-ceramic (LGC) and feldspathic ceramic (FP) received mechanical polishing or glazing. Surface roughness (Ra) and microhardness (VHN) were obtained with a profilometer and a hardness tester, respectively, before and after each oral hygiene procedure (TB: toothbrushing; PB: prophylaxis with paste and rubber cup; and BJ: prophylaxis with bicarbonate jet). ANOVA, paired t and Tukey's tests were applied (a=0.05). For both materials, only BJ affected Ra's values when mechanical polishing was performed. Moreover, no significant variations in VHN were observed only for LGC glazed with TB. Significant Ra and VHN changes in both materials were observed with BJ. Besides, BJ exhibited similar effects to TB on VHN, regardless of the material and finishing protocol used. Changes in mechanical and surface properties varied with the finishing protocol and the oral hygiene method. In general, prophylaxis with bicarbonate jet was the most harmful method for both materials and the type of finishing protocol did not have a protective effect against changes produced by oral hygiene methods.


RESUMEN: El objetivo de este estudio in vitro fue evaluar los efectos de los protocolos de acabado y los procedimientos de higiene oral sobre la superficie y las propiedades mecánicas de las cerámicas CAD/CAM. Los especímenes (n = 96, (15x10x2mm) de vitrocerámica de leucita (LGC) y cerámica feldespática (FP) recibieron pulido mecánico o glaseado. La rugosidad de la superficie (Ra) y la microdureza (VHN) se obtuvieron con un perfilómetro y un probador de dureza, respectivamente, antes y después de cada procedimiento de higiene oral (TB: cepillado dental; PB: profilaxis con pasta y vaso de hule; y BJ: profilaxis con chorro de bicarbonato). Se aplicaron ANOVA, t pareada y prueba de Tukey (a=0.05). Para ambos materiales, solo BJ afectó los valores de Ra cuando se realizó el pulido mecánico. Además, no se observaron variaciones significativas en VHN solo para LGC vidriado con TB. Se observaron cambios significativos de Ra y VHN en ambos materiales con BJ. Además, BJ exhibió efectos similares a TB en VHN, independientemente del material y protocolo de acabado utilizado Los cambios en las propiedades mecánicas y superficiales variaron con el protocolo de acabado y el método de higiene oral. En general, la profilaxis con chorro de bicarbonato fue el método más perjudicial, tanto los materiales como el tipo de protocolo de acabado no tuvieron un efecto protector frente a los cambios producidos por los métodos de higiene oral.


Subject(s)
Ceramics/therapeutic use , Oral Health , Surface Properties , In Vitro Techniques , Materials Testing , Analysis of Variance , Dental Prosthesis Design/methods , Dental Materials/therapeutic use , Dental Polishing
14.
Annals of Dentistry ; : 1-8, 2022.
Article in English | WPRIM | ID: wpr-929412

ABSTRACT

@#Heat-cured PMMA is one of the most frequently used materials in the manufacture of removable dentures. Heat-cured material used to fabricate dentures contain soluble elements, allowing the material to absorb and release substances. These factors all directly affect the longevity and performance of protheses fabricated from polymethyl methacrylate denture base material. Various procedures associated with fabrication of removable dentures from heat-cure denture base material are reported to significantly influence the sorption and solubility experienced by the prosthesis. A comprehensive search of peer-reviewed journals located within academic databases was conducted to identify relevant literature pertaining to sorption and solubility of denture base materials. Key aspects of each paper were captured in Microsoft® Excel® to record author/s, location, study design, sample size, methodology, results and conclusions. Mixing ratios and polymerisation cycles have been identified as variables that can negatively influence the rate of sorption and solubility of denture base materials during the fabrication process. Certain surface treatment procedures, as well as storing the denture in artificial saliva solution may reduce the levels of sorption and solubility experienced and optimise its lifespan. In this review we identify these factors and consider the detrimental effects of sorption and solubility on denture base acrylic materials.

15.
Article in Chinese | WPRIM | ID: wpr-942768

ABSTRACT

@#Polyetheretherketone (PEEK) is known as a high-grade engineering plastic with good mechanical properties, chemical stability and biocompatibility. Currently, PEEK materials have been widely used in prosthodontics, such as complete dentures and removable partial dentures. The relevant research shows that PEEK posts are superior to glass fiber posts, which have high tensile bond strength and bending strength. At present, few case reports of PEEK postcores have been published, and clinical case reports suggest that PEEK postcores have good oral prosthetic aesthetics and are ideal and reliable postcore crown materials. However, the preparation and surface treatment methods of PEEK require further refinement. A review of the related properties of PEEK and the prospects of its application in the field of postcore crown restoration will be presented in this paper.

16.
Article in Chinese | WPRIM | ID: wpr-923364

ABSTRACT

Objective@#To compare the efficiency and biocompatibility of four different silanes on immobilizing c(RGDfK) peptide on titanium surface.@*Methods @# After alkali-heat treatment (group OH), the titanium surface was treated with 3-aminopropyltriethoxysilane (APTES) (group OHAP), 3-chloropropyltriethoxysilane (CPTES) (group OHCP) (3-mercaptopropyltrimethoxysilane (MPTS) (group OHMPT) and 3-isobutyryloxy propyltrimethoxysilane(γ- MPS) (group OHMPS) to immobilize the c(RGDfK) cyclic peptide and constructa titanium-silane-c(RGDfK) coating. The NT group was the blank control group. The surface morphology and wettability of the coatings were detected using scanning electron microscopy and contact angle measurement. The elemental composition of the titanium surface was analyzed using X-ray photoelectron spectroscopy. After fluorescent staining with 4’,6-diamino-2-phenylindole (DAPI) and phalloidin, the adhesion of mouse preosteoblast MC3T3-E1 cells on the surface of the materials was observed using laser confocal microscopy. Cell counting kit-8 (CCK-8) and alkaline phosphatase (ALP) activity assays were used to evaluate the proliferation and osteogenic differentiation of MC3T3-E1 cells on the surface of the materials, respectively. @*Results @#Scanning electron microscope observation showed a spongy-like 3-dimensional network formed on the titanium surface after alkali-heat treatment with silane-c(RGDfK) coating adhesion. The wettability of each group was greatly improved compared to the untreated titanium surface. The element ratios of Si/Ti and amide-N/Ti in the OHMPS group were the highest. The OHAP group exhibited the best cell adhesion effect. The cell proliferation and ALP activity of the OHAP, OHMPT, and OHMPS groups were significantly higher than the control group (P <0.05); there was no statistical difference between the OHCP group and the control group.@*Conclusion @#MPTS, CPTES and γ-MPS covalently immobilized cyclic peptide c(RGDfK) on the titanium surface, which promoted adhesion, proliferation and osteogenic differentiation of MC3T3-E1 cells. Theγ-MPS conjugated C (RGDfK)cyclic peptide exhibited the best effect. MPTS, CPTES and γ-MPS coupled with c(RGDfK) cyclic peptides had similar biological properties.

17.
Article in Chinese | WPRIM | ID: wpr-881256

ABSTRACT

@#Hydrofluoric acid is a common surface treatment agent for glass ceramic restorations before bonding. However, the use of hydrofluoric acid has a high safety risk, so the search for hydrofluoric acid substitutes has been a research hotspot. Tetrabutylammonium dihydrogen trifluoride is a kind of fluoride, whose chemical activity is lower than that of hydrofluoric acid, so it’s safer, and the surface morphology changes on glass ceramics caused by it are smaller and more superficial. At present, the vast majority of laboratory studies and clinical case reports indicate that the mechanical strength and bonding strength of glass ceramics treated with tetrabutylammonium dihydrogen trifluoride can meet the clinical requirements. In the future, according to the research results, the performance of porcelain surface treatment agents containing tetrabutylammonium dihydrogen trifluoride can be further improved, and more hydrofluoric acid substitutes may be developed. In this review, the research progress of tetrabutylammonium dihydrogen trifluoride as a substitute for hydrofluoric acid is reviewed in terms of the influence of the surface morphology, mechanical strength, and bonding strength of glass ceramics.

18.
Article in Chinese | WPRIM | ID: wpr-882187

ABSTRACT

Objective@#To prepare a copper-nobium antibacterial coating on a titanium surface by a microarc oxidation-microwave hydrothermal two-step method and to study its surface structure and antibacterial properties.@*Methods@#Using titanium coated with a microarc oxidation coating (MAO group) as the substrate, copper and niobium were introduced by a microwave hydrothermal method in low (MHL-Cu group), medium (MHM-Cu group) and high (MHH-Cu group) copper chloride solutions and niobium oxalate (MH-Nb group) solutions, respectively. The component with the highest copper content was determined by energy spectrum analysis, and the copper-niobium composite coating (MH-Cu/Nb group) was prepared by microwave hydrothermal mixing with niobium oxalate. The microstructure, element distribution and phase composition of the specimens were characterized by scanning electron microscopy, energy dispersive spectrometry and X-ray diffraction, and the bacteriostatic effect of the coating onEscherichia coliand Staphylococcus aureus was determined by the film method. @* Results@#Energy dispersive spectrometry showed that Cu was introduced onto the surface of the MHL-Cu, MHM-Cu, and MHH-Cu groups, and the atomic ratios of copper in each group were (0.68 ± 0.04)%,(1.17 ± 0.06)%, and (1.64 ± 0.03)%. The difference between groups was statistically significant (P< 0.01). Scanning electron microscopy showed a crater-like porous structure on the surface of the MAO group, and the MHL-Cu, MHM-Cu, MHH-Cu, MH-Nb, MH-Cu/Nb groups maintained micropore morphology. The roughness increased with increasing Cu2+ concentration, in which the MH-Nb and MH-Cu/Nb groups showed gully like structures simultaneously. X-ray diffraction showed that the coating of the MAO group was mainly composed of titanium and anatase phase TiO2, and the coatings of the MHL-Cu, MHM-Cu, MHH-Cu, MH-Nb, MH-Cu/Nb groups were mainly composed of anatase and rutile phase TiO2. Compared with the MAO group, Escherichia coli and Staphylococcus aureus in the MHH-Cu, MH-Nb, MH-Cu/Nb groups decreased to varying degrees, with significant differences (P< 0.001); compared with the MH-Cu/Nb group, the colony number difference had statistical significance (P> 0.05)@*Conclusion@#The rough, porous coating containing copper and niobium prepared by the microarc oxidation-microwave hydrothermal two-step method can effectively inhibit the growth ofEscherichia coli and Staphylococcus aureus.

19.
Article in Chinese | WPRIM | ID: wpr-862451

ABSTRACT

Objective@# To study the effects of different concentrated sulfuric acid etching durations on the shear bond strength between polyether-ketone-ketone (PEKK) and dentin, providing a scientific basis for the clinical bonding procedures of PEKK prosthesis.@*Methods@# Forty-four PEKK specimens were prepared and randomly divided into four groups: group A was the control group, which was only polished with abrasive papers, group B, group C and group D were experimental groups, which were etched by 98% concentrated sulfuric acid for 5 s, 30 s and 60 s, respectively. In addition, one sample was randomly selected from each group, and the profile was prepared by a slow cutting machine. The surface morphology of the profile was observed under SEM. After the four groups of specimens and dentin were bonded by resin, they were soaked in distilled water at 37 ℃ for 24 h. After the shear bonding strengths were measured, the fracture interfaces of the specimens were examined by the scanning electron microscopy and stereomicroscopy, and failure models of bonding were analyzed. @*Results@#After acid etching treatments, the cross-sectional images in group B presented uniform spongy shapes, while the cross-sectional images in group C and group D showed destructive pore structures. The shear bond strengths of group B (16.84 ± 1.84) MPa, group C (12.33 ± 1.22) MPa and group D (6.44 ± 1.18) MPa were higher than that of group A (3.99 ± 1.06) MPa (P < 0.05). The highest shear bond strength was observed in group B (16.84 ± 1.84) MPa. @*Conclusion @#The surface treatment of 98% sulfuric acid etching for 5 s manifested the best bond strength between PEKK and dentin.

20.
Article in Chinese | WPRIM | ID: wpr-843021

ABSTRACT

@#Resin-modified glass ionomer cement (RMGIC) has good physical, chemical and biological properties and is suitable for the treatment of deciduous caries, aged root surface caries and wedge-shaped defects. Surface treatment is a common method to improve bonding strength, which can improve physical and chemical retention between different components. This paper mainly introduces the current research status of the influence of different dentin surface treatment methods on the bonding strength of RMGIC. At present, the common dentin surface treatment methods are pretreatment, acid etching, laser treatment, etc. The pretreatment agent can improve the bond strength of RMGIC by increasing the surface area and porosity of dentin. The bond strength of RMGIC could be effectively improved after the dentin was treated by an acid-etching bonding system. The dentin was treated with a laser to obtain a higher bonding strength. However, whether the use of resin adhesives will affect the release of fluoride ions in RMGIC into the deep dentin and thus affect the repair effect also needs further research.

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