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1.
Braz. j. oral sci ; 21: e224265, jan.-dez. 2022. tab
Article in English | LILACS, BBO | ID: biblio-1354719

ABSTRACT

Aim: This study assessed the color and translucency stability of a polymer infiltrated ceramic network (PICN) and compared it with a resin composite (RC) and a feldspathic ceramic (FEL). Methods: Disc-shaped samples of a PICN (Vita Enamic), a feldspathic ceramic (Vitablocks Mark II), and a resin composite (Brava block) were prepared from CAD/CAM blocks. PICN and RC surfaces were finished with a sequence of polishing discs and diamond paste. FEL samples received a glaze layer. The samples were subjected to 30-min immersions in red wine twice a day for 30 days. CIEL*a*b* coordinates were assessed with a spectrophotometer at baseline and after 15 and 30 days of immersion. Color alteration (ΔE00) and translucency parameter (TP00) were calculated with CIEDE2000. Average roughness was measured before the staining procedures. Color difference and translucency data were analyzed with repeated-measures ANOVA and Tukey's tests. Roughness was analyzed with the Kruskal-Wallis test. Results: Roughness was similar among the experimental groups. All materials had their color alteration significantly increased from 15 to 30 days of staining. PICN reached an intermediate ΔE00 between FEL and RC at 15 days. PICN revealed a color alteration as high as the composite after 30 days. No statistical difference was observed regarding translucency. Conclusion: PICN was not as color stable as the feldspathic ceramic at the end of the study. Its color alteration was comparable to the resin composite when exposed to red wine. However, the translucency of the tested materials was stable throughout the 30-day staining


Subject(s)
Surface Properties , Materials Testing , Ceramics , Computer-Aided Design , Color , Composite Resins
2.
São Paulo; s.n; 20220720. 185 p.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1379715

ABSTRACT

O desgaste dentário é um processo de perda de estrutura dental, de etiologia multifatorial, com incidência crescente na população e ocasionado, principalmente, pela frequência do contato da superfície dentária com substâncias químicas e mecânicas, resultantes da alimentação e de hábitos orais. Os efeitos da ação dos desafios químicos e/ou mecânicos no dente, hígido ou restaurado, podem variar conforme as propriedades e características do substrato dentina, material restaurador. O estudo objetivou analisar os efeitos dos desafios erosivo (DE) e erosivo-abrasivo (DEA) na superfície de diferentes materiais restauradores (MR), sistemas adesivos (SA) e da dentina adjacente às restaurações (DAR). Molares humanos hígidos (n=75) foram limpos e preparados até obtenção de dentina oclusal uniforme. Os espécimes foram aleatoriamente divididos em 5 grupos (n=15). Na superfície dentinária, uma cavidade 4 x 2 mm foi confeccionada por meio de uma ponta diamantada, e restaurada por diferentes tipos de SR: Amaris® (AMA), Beautifil® II (BEA), ClearfilTM SE Bond 2 (CFB), FL-Bond II (FLB) e RIVA Self Cure (RIVA). Após restauração, a superfície do espécime foi delimitada em três partes duas, nas extremidades, que foram protegidas por fita adesiva anticorrosiva, e uma, intermediária (2 mm), que foi deixada livre para exposição da área aos desafios. No DE, o espécime foi imerso em solução de ácido cítrico 1% (pH 2.3) por dois min, seguido de imersão em saliva artificial por 60 min. Esse ciclo foi realizado durante 5 dias (6x/dia). No DEA, os espécimes foram submetidos ao mesmo DE descrito, porém foram escovados em máquina de escovação (escova macia, 45 ciclos/150g/15s), 2x/dia (após 30 min do primeiro e do último ciclo erosivo do dia). Os efeitos dos desafios foram avaliados pela análise das propriedades de perda de superfície (PS, m) e rugosidade superficial (RS, m) (Perfilometria óptica); e dureza superficial (HB, nanoindentação, Kg/mm2). Os dados foram analisados estatisticamente (p=0.05) pelos testes ANOVA, de Tukey e pela Correlação Linear de Pearson. Após desafios, as DAR de todos os grupos apresentaram elevada perda e diminuição na dureza. O DE ocasionou maior PS na dentina (PS>20 m). Não houve diferença entre a rugosidade dos materiais restauradores após desafios. O material RIVA apresentou elevada perda (PS>2 m), elevada rugosidade (RS=0.93048±0.2) e diminuição na dureza (HB<35 Kg/mm2) após desafios, principalmente após escovação. A rugosidade dentinária de AMA+CFB (RS=0.61921±0.1) foi menor após abrasão. Os desafios agiram igualmente sobre a dureza da interface adesiva. A dureza da interface de BEA+FLB (HB=16.97627±2.32) foi menor após escovação. Após erosão, a dureza dos materiais bioativos BEA, FLB e RIVA reduziram. Os efeitos observados dependeram do tipo de desafio e substrato envolvido no processo. A ação isolada do ácido cítrico foi mais agressiva no substrato dentinário. Os desafios tiveram efeitos sobre as propriedades dos materiais restauradores, principalmente nas dos bioativos. Nenhum material foi eficaz contra a desmineralização severa da dentina.


Subject(s)
Surface Properties , Tooth Abrasion , Tooth Wear
3.
Article in English | WPRIM | ID: wpr-929051

ABSTRACT

Polyetheretherketone (PEEK) has been widely applied in orthopedics because of its excellent mechanical properties, radiolucency, and biocompatibility. However, the bioinertness and poor osteointegration of PEEK have greatly limited its further application. Growing evidence proves that physical factors of implants, including their architecture, surface morphology, stiffness, and mechanical stimulation, matter as much as the composition of their surface chemistry. This review focuses on the multiple strategies for the physical modification of PEEK implants through adjusting their architecture, surface morphology, and stiffness. Many research findings show that transforming the architecture and incorporating reinforcing fillers into PEEK can affect both its mechanical strength and cellular responses. Modified PEEK surfaces at the macro scale and micro/nano scale have positive effects on cell-substrate interactions. More investigations are necessary to reach consensus on the optimal design of PEEK implants and to explore the efficiency of various functional implant surfaces. Soft-tissue integration has been ignored, though evidence shows that physical modifications also improve the adhesion of soft tissue. In the future, ideal PEEK implants should have a desirable topological structure with better surface hydrophilicity and optimum surface chemistry.


Subject(s)
Benzophenones , Ketones/chemistry , Polyethylene Glycols/chemistry , Polymers/chemistry , Surface Properties
4.
Braz. oral res. (Online) ; 36(Jun): e082, 2022.
Article in English | LILACS, BNUY, BNUY-Odon | ID: biblio-1372593

ABSTRACT

Abstract The objective of the present study was to evaluate the effect of irradiance and radiant exposure on the chemical-mechanical properties of a resin composite. A micro-hybrid resin composite (Clearfil AP-X, Kuraray) was investigated under two different irradiances: low (300 mW/cm2) and high (800 mW/cm2) and radiant exposures: 8 and 16 J/cm2. Four groups, named Low 8 J/cm2, High 8 J/cm2, Low 16 J/cm2, and High 16 J/cm2 were tested, and their flexural strengths, elastic moduli, depths of cure, and degrees of conversion were evaluated. Data were analyzed using two-way ANOVA and Tukey's test. A multiple linear regression model was used to correlate the irradiance and radiant exposure with dependent variables (α = 0.05). Irradiance and radiant exposure were found statistically significant for all dependent variables. The interaction between the factors was statistically significant only for the degree of conversion and elastic modulus. Group Low 16 J/cm2 exhibited a significantly superior performance in all the evaluated properties. Barring the degree of conversion, no significant differences were observed among the properties evaluated between the Low 8 J/cm2 and High 8 J/cm2 groups. The adjusted R2 values were high for the depth of cure and degree of conversion (0.58 and 0.96, respectively). Both irradiance and radiant exposure parameters play an important role in establishing the final properties of a micro-hybrid resin composite. Irradiance has a greater influence under higher radiant exposures.


Subject(s)
Materials Testing , Composite Resins , Dental Materials , Curing Lights, Dental , Polymerization , Flexural Strength , Surface Properties
5.
Pesqui. bras. odontopediatria clín. integr ; 22: e210044, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1365224

ABSTRACT

ABSTRACT Objective To assess the effects of coloring beverages on the color stability of two types of hybrid ceramics with different surface treatments. Material and Methods 180 specimens of two hybrid ceramics (Vita Enamic and Mazic Duro) and a feldspathic ceramic (Vita Mark II) were prepared (n=60 in each group). Half of the discs in each group were glazed while the other was polished. The specimens were then divided into three subgroups and immersed in distilled water, carrot juice, and coffee. The overall color difference (∆E) was calculated based on CIE L*a*b* color space. Data were analyzed using three-way and one-way ANOVA; Tukey's honest significant difference was also done for pairwise comparisons (α=0.05). Results Vita Mark II specimens revealed less overall color changes compared to other groups. The ∆E of the glazed Vita Enamic specimens was greater than polished specimens following immersion in distilled water (p=0.03) and coffee (p=0.001), but it was not significant for carrot juice. The same results were obtained for polished Mazic Duro specimens. Relatively similar amounts of ∆E were recorded in polished and glazed subgroups of Vita Mark II. Conclusion The ∆E of hybrid ceramics was higher than Vita Mark II. Polishing could be recommended for surface treatment of hybrid ceramics instead of glazing, saving time and facilitating the process.


Subject(s)
Spectrophotometry/instrumentation , Surface Properties , Beverages , Color , Dental Cements , Distilled Water , Ceramics , Analysis of Variance , Dental Prosthesis , Computer-Aided Design/instrumentation , Coffee , Dental Porcelain , Coloring Agents , Fruit and Vegetable Juices , Iran/epidemiology
6.
Braz. j. oral sci ; 20: e213736, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1253012

ABSTRACT

Although Spondias mombin L. extract has an excellent antimicrobial effect against oral microorganisms, it should be clarified how it affects enamel surface properties. Aim: To evaluate the color change, wettability/contact angle, surface roughness and morphology of bovine enamel submitted to the Spondias mombin L. extract. Methods: Thirty bovine teeth were distributed into the following groups: 0.12% chlorhexidine digluconate, 1:32 Spondias mombin L. extract and distilled water. Color change (CC) was evaluated after immerging specimens into the solutions for 14 days. Surface roughness (Ra) was measured using a roughness meter; wettability/contact angles (CA) were determined by the sessile drop method, and scanning electron microscopy images were obtained to characterize the morphology (SMA). The pH of the solutions was evaluated using a pHmeter. The Ra, CA, and CC data were parametric (Kolmogorov-Smirnov; p>0.05). Two-way ANOVA (for Ra and CA) and one-way ANOVA (for CC) with Tukey's posthoc tests at a significance level of 5% were used. SMA was analyzed descriptively. Results: The Spondias mombin L. extract revealed an acidic pH, and when in contact with the bovine teeth, it increased the wettability, but it did not cause statistically significant differences in the Ra. Spondias mombin L. extract caused the highest color change. The SEM images showed differences in the specimens' surface submitted to the extract compared to the other groups. Conclusion: Spondias mombin L. extract provided negative effects on bovine enamel's surface, including a high color change and a more wettable substrate


Subject(s)
Animals , Cattle , Surface Properties , Anacardiaceae , Dental Enamel , Phytotherapy , Mouthwashes
7.
Braz. j. oral sci ; 20: e211670, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254259

ABSTRACT

Aim: To evaluate the effect of different surface treatments and adhesive approaches on the microshear bond strength of resin cement to a polymer-infiltrated ceramic network (PICN). Methods: PICN blocks were randomly assigned into 9 groups (n=10): CTRL: no treatment; HF: 5% hydrofluoric acid etching; HF-S: HF + silane; HF-S-A: HF-S + adhesive (Adper Single Bond 2); HF-UA: HF + universal adhesive (Single Bond Universal); SB: sandblasting with 50 µm Al2O3 particles; SB-S: SB + silane; SB-S-A: SB-S + adhesive; SB-UA: SB + universal adhesive. Resin cement microcylinders (Ø = 0.96 mm; height = 1 mm) (RelyX Ultimate) were built upon the PICN surface after roughness and contact angle measurements. Next, microshear bonding tests (µSBS) were performed (0.5 mm/min) after water storage (37ºC, 90 days) and thermocycling (12,000 cycles; 5ºC-55ºC). Failure modes were observed under stereomicroscope. Bond strength data were analyzed by two-way ANOVA/Tukey's test and t-tests. Kruskal-Wallis/Dunn's tests were conducted for roughness and contact angle data (α = 0.05). Results: A rougher surface and lower contact angles were observed for Sandblasting. HF-S (18.54 ± 2.03 MPa), SB-S (19.00 ± 1.66 MPa) and SB-UA (18.07 ± 2.36 MPa) provided the highest bond strength values, followed by the other treated groups. The CTRL group resulted in lower bond strength (7.18 ± 2.34 MPa). Conclusion: Hydrofluoric acid etching followed by silane application and sandblasting followed by silane or universal adhesive are useful clinical steps to enhance bonding to PICN. Adhesive applications after HF etching have no advantages in bonding to PICN


Subject(s)
Surface Properties , Ceramics , Dentin-Bonding Agents , Resin Cements , Air Abrasion, Dental , Hydrofluoric Acid
8.
Braz. dent. j ; 32(4): 96-105, July-Aug. 2021. tab
Article in English | LILACS, BBO | ID: biblio-1345515

ABSTRACT

Abstract This study evaluated the effect of post-cure heat treatment (PCHT) on the Knoop microhardness (KHN), degree of conversion (DC), color changes, and contrast ratio (CR) of four resin composites (RCs): Z100 (3M ESPE), Z350 XT (3M ESPE), Estelite Omega (Tokuyama) and Empress Direct (Ivoclar Vivadent). Specimens (12 × 1 mm) were prepared for each material (n = 10 / group). After curing, samples were subjected to PCHT for 10 min at 100°C or 170°C. Control group was maintained at room temperature (24°C) for the same time. The DC was analyzed by FT-NIR immediately and 24 h after the PCHT (n = 3 / group). KHN was analyzed 24 h after PCHT (n = 10 / group). According to CIEDE2000 (∆E00), color measurements were obtained immediately after curing, five minutes after PCHT, and after seven days of storage in water, coffee, and red wine. Data were analyzed by One and Two-Way ANOVA (p < 0.05). Z100, Z350, and Estelite Omega showed increases in KHN with increased temperature (p < 0.05). PCHT at 100°C and 170°C led to a higher DC of all RCs (p < 0.05). Initially, the PCHT lead to increased ∆E00 values (p < 0.05), which was decreased after immersion in coffee and wine (p < 0.05). Considering the effect of PCHT and staining solutions, lower color changes were observed in the thermally treated specimens (p < 0.05). Taken collectively, the results suggest the PCHT as an economical and practical alternative to enhance direct RC's properties in direct-indirect and indirect restorations.


Resumo Este estudo avaliou o efeito do tratamento térmico pós-cura (PCHT) na microdureza Knoop (KHN), grau de conversão (DC), mudanças de cor e razão de contraste (CR) de quatro compósitos resinosos (RCs): Z100 (3M ESPE ), Z350 XT (3M ESPE), Estelite Omega (Tokuyama) e Empress Direct (Ivoclar Vivadent). Corpos de prova (12 × 1 mm) foram preparadas para cada material (n = 10 / grupo). Após a cura, as amostras foram submetidas ao PCHT por 10 min a 100 ou 170° C. O grupo controle foi mantido à temperatura ambiente (24° C) pelo mesmo tempo. O DC foi analisada por FT-NIR imediatamente e 24 h após a PCHT (n = 3 / grupo). KHN foi analisado 24 h após PCHT (n = 10 / grupo). De acordo com o CIEDE2000 (∆E00), as medidas de cor foram obtidas imediatamente após a cura, cinco minutos após a PCHT e após sete dias de armazenamento em água, café e vinho tinto. Os dados foram analisados por ANOVA de um e dois fatores (P < 0,05). Z100, Z350 XT e Estelite Omega mostraram aumentos no KHN com o aumento da temperatura (P < 0,05). PCHT a 100 ° C e 170 ° C levou a uma maior DC de todos os RCs (P < 0,05). Inicialmente, o PCHT levou ao aumento dos valores de ∆E00 (P < 0,05), que diminuiu após a imersão em café e vinho (P < 0,05). Considerando o efeito de PCHT e soluções de coloração, menores mudanças de cor foram observadas nas amostras tratadas termicamente (P < 0,05). Os resultados sugerem o PCHT como uma alternativa econômica e prática para aumentar as propriedades diretas de compósitos resinosos em restaurações diretas-indiretas e indiretas.


Subject(s)
Composite Resins , Hot Temperature , Surface Properties , Materials Testing , Coffee
9.
Braz. dent. j ; 32(3): 56-64, May-June 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345501

ABSTRACT

Abstract It aims on evaluate the effect of the test environment on static fatigue behavior of lithium disilicate-based (LD), and yttrium oxide-stabilized zirconia (YSZ) ceramics. Specimens of LD (IPS e.max CAD, Ivoclar Vivadent) and YSZ (IPS e.max ZirCAD MO, 3 mol% Y2O3, Ivoclar Vivadent) were randomly allocated into three groups: tested in air, inert (paraffin oil, Sigma Aldrich) or distilled water. The static fatigue test (n=15) was performed using a piston-on-three ball assembly, adapted from ISO 6872, as follows: starting load 100 N for LD and 300 N for YSZ; loading application time set to 1 hour for each loading step; step size of 50 N for LD and 100 N for YSZ, applied successively until fracture. Data from static fatigue strength (MPa) and time to fracture (hours) were recorded. Fractographic analysis was executed. Survival analysis corroborates absence of influence of environment on static fatigue outcomes (fatigue strength, time to fracture and survival rates) for YSZ. For LD, specimens tested in air presented statistically superior survival rate and static fatigue strength (p= 0.025). In regards of time to fracture, LD tested in air were superior than when tested in distilled water (p=0.019) or inert (p=0.017) environments. No statistical differences for Weibull modulus were observed. Failures started on the tensile stress surface. Thus, the test environment did not affect slow crack growth (SCG) mechanisms during static fatigue test of YSZ ceramics, but it plays a significant role for the static fatigue behavior of lithium disilicate-based glass ceramics, indicating a high susceptibility to SCG.


Resumo O presente estudo objetivou investigar a influência do ambiente de teste no comportamento a fadiga estática (resistência à fratura e tempo para falha) de cerâmicas à base de dissilicato de lítio (LD) e zircônia estabilizada com ítria (YSZ). Espécimes de LD (IPS e.max CAD, Ivoclar Vivadent) e YSZ (IPS e.max ZirCAD MO, 3mol% Y2O3, Ivoclar Vivadent) foram obtidos e alocados aleatoriamente em três grupos: testado em ar, em líquido inerte (óleo de parafina) ou em água destilada. O teste de fadiga estática (n= 15) foi realizado usando o teste pistão sobre três esferas, ISO 6872, da seguinte forma: carga inicial 100 N para LD e 300 N para YSZ; tempo de aplicação de carregamento definido para 1 hora para cada etapa de carregamento; tamanho do passo de 50 N para LD e 100 N para YSZ, aplicados sucessivamente até a fratura. Dados de resistência à fadiga estática (MPa) e tempo até a fratura (horas) foram registrados. A análise fractográfica foi executada. A análise de sobrevivência corrobora a ausência de influência do ambiente de teste nos resultados de fadiga estática (resistência à fadiga, tempo de fratura e taxas de sobrevivência) para a YSZ. Para LD, os corpos de prova testados em ar apresentaram taxa de sobrevivência e resistência à fadiga estática estatisticamente superiores (p= 0,025). Em relação ao tempo de fratura, os espécimes LD testados em ar foram superiores aos testados em água destilada (p= 0,019) ou em ambiente inerte (p= 0,017). Não foram observadas diferenças estatísticas para o módulo de Weibull. Todas as falhas começaram no lado onde se concentra a tensão de tração (lado de baixo) durante o teste. Com base nisso, observa-se que o ambiente de teste não afetou os mecanismos de crescimento lento de trinca durante o teste de fadiga estática da cerâmica YSZ, mas desempenha um papel significativo na resistência à fadiga estática da cerâmica de vidro à base de dissilicato de lítio, indicando alta susceptibilidade ao crescimento lento e subcrítico de trincas.


Subject(s)
Ceramics , Dental Porcelain , Surface Properties , Zirconium , Materials Testing , Computer-Aided Design , Dental Stress Analysis , Glass
10.
Braz. dent. j ; 32(3): 92-104, May-June 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345500

ABSTRACT

Abstract This in vitro study evaluated the effect of the beam homogeneity of a multiple-peak light-curing unit on the surface microhardness and the effect of toothbrushing wear on the microhardness, surface roughness, roughness profile, volume loss, and gloss retention of incremental and bulk-fill resin-based composites (RBCs). A LED light-curing unit (VALO) with four LEDs at the tip end (405, 445, 465A, and 465B nm emission peak) was used according to each manufacturer-recommended time to obtain disks (n=10) of six RBCs: Estelite Sigma Quick, Charisma Classic, Tetric EvoCeram Bulk Fill, Filtek Z250, Filtek Supreme Ultra, and Filtek Bulk Fill. Microhardness values were obtained according to each LED positioning of the light-curing unit on the top surface of the RBCs and were analyzed before and after toothbrushing regarding microhardness, surface roughness, roughness profile, volume loss, and gloss retention. Microhardness was considered homogeneous on the top surface regardless of the type of RBC or wavelength tested (p>0.05). Overall, toothbrushing did not reduce the microhardness of the RBCs but influenced the gloss values for most RBCs (p<0.001). Charisma Classic presented the greatest surface roughness and roughness profile after toothbrushing (p<0.05). Volume loss did not differ among RBCs (p>0.05). In conclusion, different wavelengths of the LED did not affect the top surface microhardness, regardless of the RBCs tested; and bulk-fill composites presented similar surface changes (microhardness, surface roughness, roughness profile, volume loss, and gloss retention) when compared to conventional composites after toothbrushing.


Resumo Este estudo in vitro avaliou a homogeneidade do feixe de um fotopolimerizador de múltiplos picos na microdureza superficial e o efeito da escovação na microdureza, rugosidade superficial, perfil de rugosidade, perda de volume e retenção do brilho de compósitos a base de resina (RBCs) incrementais ou bulk-fill. Um fotopolimerizador LED (VALO) com quatro LEDs na ponteira (405, 445, 465A e 465B nm de pico de emissão) foi usado de acordo com o tempo recomendado por cada fabricante para obtenção de discos (n=10) de seis RBCs: Estelite Sigma Quick, Charisma Classic, Tetric EvoCeram Bulk Fill, Filtek Z250, Filtek Supreme Ultra e Filtek Bulk Fill. Os valores de microdureza foram obtidos seguindo o posicionamento de cada LED na superfície superior das amostras e foram analisados antes e após a escovação quanto a microdureza, rugosidade superficial, perfil de rugosidade, perda de volume e retenção do brilho. A microdureza foi considerada homogênea no topo da superfície, independentemente do tipo de RBCs ou comprimento de onda testados (p>0.05). No geral, a escovação não reduziu a microdureza das RBCs, mas influenciou o brilho para a maioria das RBCs (p<0.001). Charisma Classic apresentou os maiores valores de rugosidade superficial e perfil de rugosidade após a escovação (p<0.05). A perda de volume não diferiu entre as RBCs (p>0.05). Em conclusão, os diferentes comprimentos de onda do LED não alteraram a microdureza do topo da superfície, independentemente das RBCs testadas; e as resinas bulk-fill apresentaram alterações superficiais similares (microdureza, rugosidade superficial, perfil de rugosidade, perda de volume e manutenção do brilho) quando comparadas às resinas convencionais após a escovação.


Subject(s)
Composite Resins , Dental Materials , Surface Properties , Materials Testing , Polymerization
11.
Rev. Ciênc. Plur ; 7(2): 47-60, maio 2021. ilus, tab
Article in Portuguese | LILACS, BBO | ID: biblio-1282724

ABSTRACT

Introdução:As atuaisresinas Bulk-Fill apresentamcomovantagens e propriedades: menor tempo clínico, baixa contração de polimerização, maior translucidez, entre outros. Objetivo:Avaliar a topografia superficial de restaurações com diferentes tipos de resina composta antes e após submetê-las a diferentes sistemas de acabamento e polimento. Metodologia:Confecção de100 corpos de prova, sendo 50 de cada composto resinoso, apresentando cinco grupos (n=10) sorteados de forma aleatória, de acordo com o sistema de acabamento e polimento empregado. Foram utilizadas as resinas Filtek Z350 XT e a Bulk Fill Filtek One Bulk Fill e os sistemas de acabamento e polimento: Discos de Lixa Sof-Lex Pop On Kit;Discos Diamantado Espiral Sof-Lex; Ponta Enhance e Broca Carbide Multilaminada nº 0283F, que foram comparados com superfície deixada pela Tira de Poliester (Controle Negativo). Após 7 dias de armazenamento em água destilada, os corpos de provaforam submetidos aoMicroscópio Eletrônico de Varredura.Resultados:Os corpos de provada resina Bulk Fill tiveram como melhor resultado o sistema de acabamento e polimentocom broca carbidee resultado não satisfatório com discodiamantado espiral Sof-lex, enquanto a ponta Enhance e lixa Sof-lex Pop Ontiveram resultados semelhantes. Os corpos de prova da resina Filtek Z350 XT tiveram melhor aspecto visual de lisura no grupo controle negativoe pior resultado no grupo com disco diamantado espiral Sof-lex. Conclusões:Dessa forma, o sistema que apresentou melhor resultado foi a broca Carbidena resina Bulk Fill, enquanto a Filtek Z350 XT apresentou-se melhor no grupo controle. Porém, ainda são necessáriosestudos para se chegar em um protocolo de acabamento e polimento mais eficiente (AU).


Introduction:The current Bulk-Fill resins have the following advantages and properties: less clinical time, low polymerization shrinkage, greater translucency, among others.Objective:Toevaluate the topography of restorations with different types of composite resin before and after submitting them to different finishing and polishing systems.Methodology:Manufacture of 100 specimens, 50 of each resin compound, presenting five groups (n = 10) drawn at random, according to the finishing and polishing system employed. Filtek Z350 XT resins and Bulk Fill Filtek One Bulk Fill andfinishing and polishing systems were used: Sof-Lex Pop On Kit Sanding Discs; Diamond Spiral Sof-Lex Discs; Tip Enhance and Multilaminated Carbide Drill nº 0283F, which were compared with the surface left by the Polyester Strip (Negative Control). After 7 days of storage in distilled water, the specimens were submitted to a Scanning Electron Microscope.Results:The Bulk Fill resin specimens had the best result of the finishing and polishing system with carbide drill and unsatisfactory result with Sof-lex spiral diamond disc, while the Enhance tip and Sof-lex Pop On sandpaper had similar results. The Filtek Z350 XT resin specimens had a better visual aspect of smoothness in the negative control group and a worse result in the group with Sof-lex spiral diamond wheel.Conclusions:Thus, the system that showed the best result was the Carbide drill in Bulk Fill resin, while Filtek Z350 XT was better in the control group. However, studies are still needed to arrive at a more efficient finishing and polishing protocol (AU).


Introducción:Las actuales resinas Bulk-Fill tienen las siguientes ventajas y propiedades: menor tiempo clínico, baja contracción de polimerización, mayor translucidez, entre otras.Objetivo: Evaluar la topografía de restauraciones con diferentes tipos de resina compuesta antes y después de someterlas a diferentes sistemas de acabado y pulido.Metodología: Fabricación de 100 probetas, 50 de cada resina compuesta, presentando cinco grupos (n = 10) extraídos al azar, según el sistema de acabado y pulido empleado. Se utilizaron resinas Filtek Z350 XT y Bulk Fill Filtek One Bulk Fill y sistemas de acabado y pulido: Discos de lijado Sof-Lex Pop On Kit; Discos Sof-Lex en espiral de diamante; Broca Realce de Punta y Carburo Multilaminado nº 0283F, que fueron comparadas con la superficie dejada por la Tira de Poliéster (Control Negativo). Después de 7 días de almacenamiento en agua destilada, lasmuestras se sometieron a un Las muestras de resina Bulk Fill tuvieron el mejor resultado del sistema de acabado y pulido con broca de carburo y un resultado insatisfactorio con el disco de diamante en espiral Sof-lex, mientras que la punta Enhance y el papel de lija Sof-lex Pop On tuvieron resultados similares. Las muestras de resina Filtek Z350 XT tuvieron un mejor aspecto visual de suavidad en el grupo de control negativo y un peor resultado en el grupo con disco de diamante en espiral Sof-lex.Conclusiones: Así, el sistema que mejor resultado mostró fue la broca Carbide en resina Bulk Fill, mientras que Filtek Z350 XT fue mejor en el grupo control. Sin embargo, aún se necesitan estudios para llegar a un protocolo de acabado y pulido más eficiente (AU).


Subject(s)
Surface Properties , Microscopy, Electron, Scanning/instrumentation , Composite Resins , Dental Polishing/instrumentation , In Vitro Techniques/methods , Brazil , Guidelines as Topic , Polymerization
12.
Braz. dent. j ; 32(1): 78-84, Jan.-Feb. 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1180726

ABSTRACT

Abstract The objective of this study was to evaluate the effect of the exposure reciprocity law of a multi-wave light-emitting diode (LED) on the light transmittance (LT), depth of cure (DOC) and degree of conversion in-depth (DC) of a bulk fill composite. A bulk fill composite (EvoCeram® bulk fill, Ivoclar Vivadent) was photoactivated using the multi-wave LED (VALO™ Cordless, Ultradent). The LED was previously characterized using a spectrophotometer to standardize the time of exposure when using the Standard or Xtra-Power modes with the same radiant exposure of 20J/cm2. LT was evaluated through samples of the bulk fill composite every millimeter till 4 mm in-depth. DOC was evaluated according to the ISO 4049. DC of the central longitudinal cross-section from each sample of the DOC test was mapped using FT-NIR microscopy. Data were statistically analyzed according to the experimental design (α=0.05; ß=0.2). The radiant exposure in the violet wavelength range for Standard and Xtra-Power was 4.5 and 5.0 J/cm2, respectively; for the blue wavelength range the radiant exposure for Standard and Xtra-Power was 15.5 and 15.0 J/cm2, respectively. There was no statistical difference in the DOC using Standard or Xtra-Power light-curing modes, but the DOC was lower than the claimed by the manufacturer (4 mm). The DC was not significantly affected by the light-curing mode up to 4 mm in depth (p>0.05). According to exposure reciprocity law, the reduction in exposure time using the same radiant exposure did not affect the depth of cure of the bulk fill composite.


Resumo O objetivo deste estudo foi avaliar o efeito da lei de reciprocidade de um diodo emissor de luz (LED) multi-wave na transmitância de luz (LT), profundidade de cura (DOC) e grau de conversão em profundidade (DC) de um compósito bulk fill. Material e Métodos: Um compósito bulk fill (EvoCeram®, Ivoclar Vivadent) foi fotoativado utilizando um LED multi-wave (VALO ™ Cordless, Ultradent). O LED foi previamente caracterizado usando um espectrofotômetro para padronizar o tempo de exposição utilizando os modos Standard ou Xtra-Power com a mesma dose de energia de 20 J/cm 2. A LT foi avaliada através de amostras do compósito bulk fill a cada milímetro até 4 mm de profundidade. O DOC foi avaliado de acordo com a ISO 4049. O DC foi realizado em forma de mapeamento da seção transversal longitudinal central de cada amostra do teste de DOC utilizando microscopia FT-NIR. Os dados foram analisados estatisticamente de acordo com o delineamento experimental (α=0,05; ß=0,2). A exposição radiante na faixa de comprimento de onda violeta para os modos Standard e Xtra-Power foi de 4,5 e 5,0 J/cm2, respectivamente; e para a faixa de comprimento de onda azul, a exposição radiante para os modos Standard e Xtra-Power foi de 15,5 e 15,0 J/cm2, respectivamente. Não houve diferença estatística no DOC utilizando os modos de fotopolimerização Standard ou Xtra-Power, mas o DOC foi menor do que o reivindicado pelo fabricante (4 mm). O DC não foi afetado significativamente pelo modo de fotopolimerização até 4 mm de profundidade (p>0,05). De acordo com a lei de reciprocidade da exposição, a redução no tempo de exposição utilizando a mesma exposição radiante não afetou a profundidade de cura do compósito bulk fill.


Subject(s)
Composite Resins , Curing Lights, Dental , Surface Properties , Materials Testing , Color , Light-Curing of Dental Adhesives , Polymerization , Hardness
13.
Braz. dent. j ; 32(1): 91-97, Jan.-Feb. 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1180719

ABSTRACT

Abstract This study investigated the effects of oxygen inhibition and finishing/polishing procedures on the composite resin properties. One bulk-fill and two conventional composite resins (nanoparticle and microhybrid) were evaluated. Specimens were prepared using 4 surface treatments: control, no treatment; Gly, oxygen inhibition with glycerin; FP, finishing and polishing; Gly + FP, glycerin followed by finishing and polishing. The degree of conversion (DC) was measured using Fourier Transformed Infrared Spectroscopy (FTIR) immediately and after 15 days (n=5). Color stability (ΔEab, and ΔE00) and opacity were evaluated using a spectrophotometer after 15 days of immersion in coffee, using the CIELAB system (n=5). Data were analyzed by two-way ANOVA and Tukey tests (α=0.05) and opacity by two-way repeated-measures ANOVA. Glycerin usage increased significantly the DC however had no influence on the ΔEab, ΔE00 and, opacity values. Finishing and polishing reduced ΔEab and ΔE00 values, regardless of composite resins. Microhybrid showed higher opacity, followed by the nanoparticle and bulk fill, regardless of surface treatment. Post-polymerization polishing procedures resulted in lower conversion than using an oxygen inhibitor agent (Gly condition), but similar staining caused by coffee.


Resumo Este estudo investigou os efeitos da inibição de oxigênio e dos procedimentos de acabamento/polimento nas propriedades das resinas compostas. Foram avaliadas uma resina composta bulk fill e duas resinas convencionais (nanoparticulada e microhíbrida). Os espécimes foram confeccionados, variando o tratamento de superfície: controle, sem tratamento; glicerina (inibidor de oxigênio); acabamento e polimento; glicerina + acabamento e polimento. O grau de conversão (GC) foi medido pela Espectroscopia de Infravermelho Transformada de Fourier (FTIR) imediatamente e após 15 dias da confecção dos espécimes (n=5). Os índices de alteração de cor ΔEab, ΔE00 e opacidade foram avaliados por meio de espectrofotômetro, após 15 dias de imersão no café, utilizando o sistema CIELAB (n=5). Os dados da alteração da cor foram analisados pelos testes ANOVA de dois fatores e Tukey (α=0,05) e a opacidade por ANOVA de medidas repetidas. O uso de glicerina aumentou significativamente o GC, no entanto, não teve influência sobre os valores ΔEab e ΔE00. O acabamento e o polimento reduziram os valores de ΔEab e ΔE00, independentemente da resina composta. A resina microhíbrida apresentou maior opacidade, seguida pela nanoparticula e bulk-fill, independentemente do tratamento de superfície. O acabamento e polimento resultou em menor grau de conversão das resinas compostas se comparado ao uso de um agente inibidor de oxigênio (glicerina), porém apresenta resultados similares para a pigmentação pelo café.


Subject(s)
Oxygen , Composite Resins , Surface Properties , Materials Testing , Color , Dental Materials , Dental Polishing
14.
Chinese Journal of Biotechnology ; (12): 4075-4082, 2021.
Article in Chinese | WPRIM | ID: wpr-921488

ABSTRACT

The rapid screening of tumor markers is a challenging task for early diagnosis of cancer. This study aims to use highly sensitive chemiluminescent protein microarray technology to efficiently screen a variety of low abundance tumor related markers. A new material, termed integrated polydimethylsiloxane modified silica gel (iPDMS), was obtained by adding a surface polymerization initiator with olefin end to the conventional polydimethylsiloxane, and fixing into the three-dimensional structure of polydimethylsiloxane by thermal crosslinking through silicon hydrogen bonding. In order to make the iPDMS material resistant to non-specific protein adsorption, a poly(OEGMA) polymer brush was synthesized by surface-initiated atom transfer radical polymerization at the active initiation site. Finally, 20 tumor-related antigens were printed into the specific areas of the microarray by high-throughput spray printing technology, and assembled into 48-well detection microtiterplates of the iPDMS microarray. It was found the VEGFR and VEGF121 autoantibodies that obtained from 8 common tumors (breast cancer, lung cancer, colon cancer, gastric cancer, liver cancer, leukemia, lymphoma and ovarian cancer) can be used as potential tumor markers. The chemiluminescence labeled iPDMS protein microarray can be used for the screening of tumor autoantibodies at early stage.


Subject(s)
Adsorption , Autoantibodies , Dimethylpolysiloxanes , Protein Array Analysis , Silica Gel , Surface Properties
15.
Article in English | WPRIM | ID: wpr-921370

ABSTRACT

OBJECTIVES@#This study was performed to fabricate a bionic coating with titanium (Ti) phosphate to promote the osseointegration of Ti substrate implants.@*METHODS@#Phosphorylated micro/nanocoating was prepared on the surface of pure titanium (i.e., TiP-Ti) by hydrothermal process under special pressure, and the untreated smooth pure titanium (cp-Ti) was selected as the control. To evaluate the characteristics of the coating surface, scanning electron microscopy, X-ray diffraction, atomic force microscopy, and contact-angle measurement were performed. In addition, the effects of TiP-Ti on the proliferation, adhesion, and differentiation of rat bone marrow mesenchymal stem cells (BMSCs) were investigated by using @*RESULTS@#The TiP-Ti surface presented a bionic structure with coexisting nanoscale 3D spatial structure and microscale pores. @*CONCLUSIONS@#A bionic structure with TiP-Ti micro/nanoscale coating was successfully fabricated, indicating a promising method for modifying the surface of implants.


Subject(s)
Animals , Dental Implants , Osseointegration , Osteogenesis , Oxides , Phosphates , Rats , Surface Properties , Titanium
16.
Article in Chinese | WPRIM | ID: wpr-880436

ABSTRACT

Effects of heat treatment conditions (including temperature and time) on the shape memory recovery and corrosion resistance of NiTi self-expanding vascular stents were studied based on working mechanism and clinical use. The


Subject(s)
Alloys , Corrosion , Hot Temperature , Materials Testing , Stents , Surface Properties , Temperature , Titanium
17.
Article in English | WPRIM | ID: wpr-878444

ABSTRACT

OBJECTIVES@#This study investigated the effects of different implant surface properties on the biological behavior of Schwann cells.@*METHODS@#Schwann cells (SCs) were cultured on three types of implant surfaces including smooth polished (SMO), sand-blasted, large grit, acid-etched (SLA), and chemically-modified SLA (modSLA). At different time points, the morphology and adhesion of SCs on the implant surfaces were observed by scanning electron microscope. Cell proliferation activity was detected by MTT method. The expression levels of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) were detected by enzyme-linked immunosorbent assay. Changes in the mRNA levels of NGF and BDNF were detected by real-time fluorescent quantitative polymerase chain reaction (PCR).@*RESULTS@#SCs adhered, stretched, and proliferated well on the three types of implant surfaces. On the 3rd, 5th, and 7th days, the OD values of the SMO group were higher than those of the SLA group and the modSLA group, and the difference was statistically significant (@*CONCLUSIONS@#Different implant surface properties have different effects on the biological behavior of SCs. Proliferation of SCs is significantly promoted by smooth surface, while secretion and gene expression of neurotrophic factors are significantly promoted by modSLA surface at early stage.


Subject(s)
Dental Implants , Schwann Cells , Surface Properties , Titanium
18.
Article in English | LILACS, BBO | ID: biblio-1351218

ABSTRACT

ABSTRACT Objective: Tocompare the effect of tooth brushing on surface roughness of Resin-Modified Glass Ionomer Cement (RMGIC; GC Gold label 2LC Light Cured Universal Restorative) and Glass Hybrid (GH; GC EQUIA SYSTEM- EQUIA Forte™ Fil and EQUIA Forte™ Coat) restorative material at 1- and 3-months interval simulated by tooth brushing. Material and Methods: RMGIC and GH material specimens (20 each) were prepared according to manufacturer instructions in 10mm × 2 mm dimensions using a mylar strip. A specially designed toothbrush simulator was used along with Oral B Pro 2 2000N powered toothbrush and Colgate Total dentifrice (Colgate-Palmolive India limited; Relative dentin abrasivity - RDA:70- Low abrasive) to perform brushing strokes. Specimens were subjected to surface roughness analysis before and after simulated tooth brushing at baseline, 1, and 3 months. Results: The intragroup comparison was done using repeated-measures ANOVA. Intergroup comparisons were done using an independent sample t-test and General Linear Model (ANCOVA). Surface roughness increased from baseline through 3 months in both RMGIC and GH groups. The mean surface roughness in RMGIC group was significantly higher than GH group at baseline 1 and 3-months, respectively (p<0.001, <0.001, and <0.001). Interaction between group and baseline surface roughness was not significant (p=0.466). The estimated marginal means were significantly higher in RMGIC than GH group (p=0.008). Conclusion: The surface roughness of both RMGIC and GH restorative increased from baseline to 1 month and 3 months after the simulated toothbrushing protocol. GH exhibited significantly lower surface roughness than RMGIC at all the tested intervals.


Subject(s)
Surface Properties , Toothbrushing/instrumentation , Microscopy, Atomic Force/instrumentation , Dental Materials , Glass Ionomer Cements , In Vitro Techniques/methods , Analysis of Variance , Statistics, Nonparametric , India/epidemiology
19.
Dental press j. orthod. (Impr.) ; 26(3): e2119177, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1286215

ABSTRACT

ABSTRACT Objective: This study aims to determine shear debonding strength of metal and ceramic brackets, and the degree of enamel crack healing. Material and Methods: Extracted human maxillary premolars were flattened on the buccal surface, and randomly separated into five groups (n = 15). In control groups (groups 1 and 2), metal and ceramic brackets were bonded on flat polished enamel, while in experimental groups (groups 3 and 4), metal and ceramic brackets were bonded on the surface with boundary where corner cracks were created. Additionally, fifteen specimens (group 5) were also prepared for an indentation procedure with no bracket installation. The degree of crack healing was measured. All brackets were detached with a universal testing machine, and the adhesive remnant index (ARI) was also identified. Healing degree and apparent fracture toughness were then calculated. Results: Between groups with similar bracket types, there was no statistically significant difference in debonding strength. Regarding bracket types, ceramic brackets provided significantly higher debonding strength than metal brackets. There was a significant difference in ARI scores between metal and ceramic brackets. The corner cracks showed signs of healing in both horizontal and vertical directions. No statistically significant difference in the healing rates among the groups was found and the apparent fracture toughness increased from the initial to the final measurement. Conclusions: Within the limitations of this study, even though ceramic brackets required significantly higher debonding force compared to metal brackets, debonding stress was limited to the bonding site and did not affect the surrounding cracks on enamel.


RESUMO Objetivo: O presente estudo teve como objetivo determinar a resistência ao cisalhamento de braquetes metálicos e cerâmicos, e o grau de reparo de fraturas no esmalte. Métodos: Pré-molares superiores, extraídos de humanos, foram aplainados na face vestibular e aleatoriamente divididos em cinco grupos (n = 15). Nos grupos controle (Grupos 1 e 2), os braquetes metálicos e cerâmicos foram colados em esmalte liso e polido; enquanto nos grupos experimentais (Grupos 3 e 4), os braquetes metálicos e cerâmicos foram colados em superfície delimitada, em cujos cantos foram criadas fissuras. Adicionalmente, foram também preparados 15 espécimes (Grupo 5) para um teste com indentação, sem a instalação de braquetes. O grau de reparo das fraturas foi avaliado. Todos os braquetes foram descolados usando uma máquina universal de testes, e o índice de adesivo remanescente (ARI) também foi avaliado. O grau de reparo e a tenacidade à fratura aparente foram então calculados. Resultados: Entre os grupos com o mesmo tipo de braquetes, não houve diferença estatisticamente significativa na força de descolagem. Com relação aos tipos de braquetes, os cerâmicos apresentaram uma força de descolagem significativamente maior do que os metálicos. Houve uma diferença significativa nos escores ARI entre os braquetes metálicos e os cerâmicos. As fraturas de canto mostraram sinais de reparo nos sentidos horizontal e vertical. Não foi detectada diferença estatisticamente significativa no grau de reparo entre os grupos, e a tenacidade à fratura aparente aumentou da mensuração inicial para a final. Conclusão: Considerando-se as limitações desse estudo, apesar de os braquetes cerâmicos necessitarem de força de descolagem significativamente maior do que os braquetes metálicos, a tensão de descolagem foi limitada ao sítio de colagem, não afetando as fraturas de esmalte ao redor.


Subject(s)
Humans , Dental Bonding , Orthodontic Brackets , Surface Properties , Materials Testing , Ceramics , Dental Debonding , Dental Cements , Dental Enamel , Shear Strength , Dental Stress Analysis
20.
Rev. Fac. Odontol. (B.Aires) ; 36(84): 47-53, 2021. ilus
Article in Spanish | LILACS | ID: biblio-1367231

ABSTRACT

Al momento de realizar una preparación dental existen diferentes alternativas. Dentro del instrumental rotatorio hay dos opciones: la turbina dental (ultra-velocidad) y el micromotor acoplado a un contra-ángulo multiplicador (alta velocidad). El propósito de este estudio fue evaluar cualitativamente la diferencia en la lisura superficial sobre esmalte, que se genera al desgastarlo, utilizando para esto, una turbina dental y un micromotor eléctrico acoplado a un contra-ángulo multiplicador 1:5 (anillo rojo). Se realizó un análisis cualitativo sobre una muestra de 24 superficies de esmalte obtenidas de 12 premolares extraídos por indicación ortodóntica, los cuales fueron preparados y observados al microscopio óptico. Luego de observar las 24 superficies al microscopio se pudo constatar una mayor lisura superficial sobre el esmalte al utilizar micromotor eléctrico acoplado a contraángulo multiplicador en comparación con turbina (AU)


Subject(s)
Dental High-Speed Equipment , Tooth Preparation , Dental Enamel , Surface Properties , Bicuspid , Qualitative Research , Dental Restoration, Permanent
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