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1.
São Paulo; s.n; 20240301. 104 p.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1532259

ABSTRACT

A fim de conter o avanço das lesões incipientes de cárie (LMB: lesões de mancha branca) e, oportunamente, de minimizar seu aspecto estético insatisfatório, a infiltração com material resinoso fotopolimerizável de baixa viscosidade e alto coeficiente de penetração vem sendo indicada. Contudo, nem sempre se consegue mascarar as LMB por completo, talvez principalmente em dentes escurecidos. Avaliou-se, pois, in vitro, o efeito do clareamento como complementação à infiltração resinosa, na dissimulação (diferença de cor do esmalte tratado vs. adjacente) de LMB em esmalte bovino artificialmente escurecido, comparativamente ao normal. Fragmentos de 6 x 3 mm, obtidos de incisivos bovinos, foram planificados e polidos, avaliados quanto à microdureza superficial (KHN, 50 g, 10 s), e distribuídos em sete grupos (n=15): N.L, N.LI, NB.LIB, E.L, E.LI, EB.LIB e C. O esmalte dos espécimes dos grupos E foi artificialmente escurecido (100 ml de água destilada / 25 g de café solúvel, 15 dias; E: escurecido), e o daqueles dos grupos N, não (N: normal). Na metade direita (região tratada - 3 x 3 mm) de todos eles, então, determinou-se uma LMB (tampão de acetato 50 mM, 64 horas, 37 oC), que não recebeu qualquer tratamento (L: lesão nenhum tratamento), ou foi apenas infiltrada H3PO4 37% / 10 s; Icon®-Dry / 30 s; Icon®- Infiltrant / 3 min + 1 min; LI: lesão infiltrada), ou infiltrada e, como o esmalte adjacente (metade esquerda, região referência/baseline - 3 x 3 mm), submetida a clareamento/bleaching (Opalescence Boost 40%, 3x de 20 min cada; LIB: lesão infiltrada e clareada; NB e EB: esmalte adjacente normal ou escurecido clareado). O esmalte de ambas as metades dos espécimes do grupo C (C: controle) não foi submetido a nada além da planificação e do polimento. Determinou-se os valores de E00, L, a e b (fórmula CIEDE2000), considerando-se como referência/baseline, em um mesmo espécime, a superfície de esmalte adjacente (metade esquerda) àquela devidamente desmineralizada / desmineralizada e tratada (metade direita) e, como a referência, submetida, ou não, a clareamento dentário. Para o grupo controle, tal diferença foi determinada entre suas duas metades. Considerando-se como fatores experimentais a condição inicial do esmalte (em 2 níveis) e o tratamento da LMB, bem como do esmalte adjacente, quando pertinente (em 3 níveis), analisou-se estatisticamente os dados por meio de ANOVA a 2 critérios e teste de Tukey. Para comparar cada um dos grupos experimentais entre si e com o grupo C, empregou-se o teste de Kruskal-Wallis e o de Dunn para E00, L e a, e ANOVA a 1 fator e teste de Tukey para b. Em todos os casos adotou-se =0,05. Independentemente se o clareamento é realizado, ou não, a infiltração resinosa é capaz de mascarar as LMB tanto no esmalte normal, quanto no escurecido. Ora, é indiferente realizar o clareamento como complementação à infiltração resinosa na dissimulação de LMB.


Subject(s)
Tooth Bleaching , Color , Esthetics
2.
Braz. j. oral sci ; 23: e240869, 2024. ilus
Article in English | LILACS, BBO | ID: biblio-1537143

ABSTRACT

Aim: The aim of this study was to verify the color variation between different composite resins and the Vita Classical Shade Guide. Methods: Two-millimeter thickness samples were made (n = 6) from eight commercial brands of composite resin (shade A2): Charisma (Kulzer), Forma (Ultradent), Harmonize (Kerr), Luna (SDI), Opallis (FGM), Oppus Bulk Fill (FGM), Vittra (FGM) and Filtek Z250 XT (3M ESPE). Specimens were stored in distilled water for 7 days and then polished. Color measurements of samples and A2 shade of the Vita Classical Shade Guide were performed using the Vita Easy Shade Advance 4.0 spectrophotometer on a black background. Color variations were calculated using the CIEDE2000 formula, considering values ≥0.81 being noticeable by the human eye and ≥1.77 being clinically unacceptable. Results were statistically analyzed with a 5% significance level. Results: Color variation (ΔE) of composite (E1 ) compared to the Vita Classical Shade Guide (E0 ) was greater than clinically acceptable for all the materials evaluated in this study. Forma (ΔE=2.08 ± sd=0.47) and Filtek Z250 XT (2.50 ± 0.20) had the smallest amount of color variation values found in the results. Harmonize (3.32 ± 0.63) presented values similar to Filtek Z250 XT, but it was worse than Forma. Vittra (3.51 ± 0.28), Charisma (3.80 ± 0.20), Opallis (4.24 ± 0.30) and Luna (5.67 ± 0.20) did not differ among each other and presented higher color variation than Forma, Filtek Z350XT and Harmonize. Oppus Bulk Fill (13.94 ± 1.12) was the composite with the greatest color variation. Conclusions: The findings in this study show that attention should be taken when using the Vita Color Shade Guide for composite shade selection


Subject(s)
Spectrophotometry , Distilled Water , Color , Composite Resins
3.
Braz. j. oral sci ; 23: e241390, 2024. ilus
Article in English | LILACS, BBO | ID: biblio-1550150

ABSTRACT

Aim: To evaluate the surface roughness and color stability of bulk-fill resin composites after simulated toothbrushing with whitening dentifrices. The radioactive/relative dentin abrasion (RDA) and radioactive/relative enamel abrasion (REA) of dentifrices were also assessed. Methods: Specimens (n=10) of Tetric N Ceram Bulk Fill (TNCB), Filtek One Bulk Fill (FOB) resin composites, and Z100(Control) were prepared using a cylindrical Teflon matrix. Surface roughness (Ra, µm) was assessed by a roughness meter and the color evaluations (ΔEab , ΔE00 , WID ) were performed using a digital spectrophotometer based on the CIELAB system. Three measurements were performed per sample, before and after simulated toothbrushing with 3D Oral-B White Perfection (3DW) and Black is White (BW) dentifrices. The abrasivity (REA and RDA values) of the used dentifrices was also determined by the Hefferren abrasivity test. Results: The Ra values increased significantly in all resin composites after 3DW and BW toothbrushing. The acceptable threshold color varied among resin composites, and TNCB and Z100 presented the highest ΔEab and ΔE00 for BW dentifrice. The 3DW dentifrice was significantly more abrasive than BW dentifrice on enamel and dentin. Conclusions: simulated toothbrushing with tested whitening dentifrices increased the surface roughness at acceptable levels. The Tetric N Ceram Bulk-fill and Z100 composite showed the highest color alteration in BW. 3D White Perfection dentifrice was more abrasive on dentin and enamel than Black is White.


Subject(s)
Color , Composite Resins , Dental Enamel , Dentifrices , Dentin , Bleaching Agents
4.
Pesqui. bras. odontopediatria clín. integr ; 24: e220192, 2024. tab, graf
Article in English | LILACS, BBO | ID: biblio-1550593

ABSTRACT

ABSTRACT Objective: To investigate the effects of two different dentifrice fluoride concentrations on the color stability of the composite. Material and Methods: Twenty-seven specimens (2×4×5 mm) each of microfilled (Gradia, GC, Japan) and nanohybrid (Grandio, VOCO, Germany) composites were prepared. The specimens were randomly divided into six groups (control, Fluoflor caries protection toothpaste with 1450ppm Fluoride (EXW, France), and Fluoflor kids toothpaste with 500ppm Fluoride (EXW, France) (n = 9). The specimens were immersed in a mixture of artificial saliva and toothpaste in a ratio of 1:3 and applied for 60 seconds every 12 hours for 42 days. The control samples were incubated in artificial saliva at 37°C. Primary and secondary color measurements were performed using color parameters (L∗a∗b) with a spectrophotoshade (MHT Optic Research AG, Niederhasli, Switzerland). Data were analyzed using a two-way analysis of variance at a significance level of 0.05. Results: According to the two-way ANOVA analysis, there was no significant difference in color change between the composites and no difference in the level of discoloration between different fluoride concentrations(p>0.05). Also, None of the dentifrices caused clinically significant color changes(∆E˂3.3). Conclusion: No clinically unacceptable color changes were observed in the microfilled and nanofilled composites with different concentrations of fluoride toothpaste.


Subject(s)
Toothpastes/chemistry , Color , Composite Resins/chemistry , Fluorides/chemistry , In Vitro Techniques/methods , Analysis of Variance , Dentifrices
5.
Rev. Ciênc. Plur ; 9(3): 32620, 26 dez. 2023. tab, ilus, graf
Article in Portuguese | LILACS, BBO | ID: biblio-1524464

ABSTRACT

Introdução:Sabe-se que a busca pela estética é algo cada vez mais crescente. Dentre os procedimentos mais procurados na odontologia estética, destaca-se o clareamento dental de consultório. Diante disso, ainda são poucos os estudos que avaliam os efeitos dos agentes clareadores de diferentes pHs na efetividade clareadora e na sensibilidade dentária.Objetivo:Avaliar a sensibilidade dentária e a eficácia clareadora de géis clareadores à base de peróxido de hidrogênio a 35% com diferentes pHs.Metodologia:Trata-se de um relato de três casos, descritivo e observacional, do tipo boca dividida (split-mouth) para cada estratégia clareadora (gel clareador com pH básico e gel clareador com pH ácido). Foram avaliados três pacientes de25, 26e 27anos de idade.Realizou-se registro de cor por meio da escala VITAClassical e avaliação da sensibilidade dentária pela escala visual analógica. Resultados:Todos os pacientes avaliados apresentaram cor A3 no registro de cor inicial e, após o clareamento dental,atingiram a cor A1. Todos relataram uma maior sensibilidade no hemiarco direito (local onde foi aplicada o gel clareador Whiteness HP que possui pH ácido. Dois pacientes relataram sensibilidade dentária no hemiarco esquerdo em que foi aplicado o gel clareador de pH básico. Conclusões:Observa-se a eficácia clínica dos géis clareadores de consultório à base de peróxido de hidrogênio a 35% na estabilidade de cor após o tratamento clareador, independente do seu pH. Ademais, nota-se que o gel clareador de pH básico promoveu menor sensibilidade pós-operatória (AU).


Introduction:It is known that the search for aesthetics is something increasingly growing. Among the most sought-after procedures in cosmetic dentistry, in-office tooth bleaching stands out. Therefore, there are still few studies that evaluate the effects of bleaching agents ofdifferent pHs on bleaching effectiveness and tooth sensitivity.Objective:To evaluate tooth sensitivity and bleaching efficacy of 35% hydrogen peroxide-based tooth bleaching gels with different pHs.Methodology:This is a report of three cases, descriptive and observational, of the split-mouth type for each bleaching strategy (bleaching gel with basic pH and bleaching gel with acidic pH). Three patients aged 25, 26 and 27 years were evaluated. Color registration was performed using the VITA Classical scale and tooth sensitivity was evaluated using the visual analogue scale.Results:All evaluated patients presented color A3 in the initial color registration and, after tooth bleaching, reached color A1. All reported greater sensitivity in the right hemi-arch (place where the Whiteness HP bleaching gel with an acid pH was applied. Two patients reported tooth sensitivity in the left hemi-arch where the basic pH bleaching gel was applied.Conclusions:The clinical efficacy of in-office tooth bleaching gels based on 35% hydrogen peroxide in terms of color stability after bleaching treatment is observed, regardless of its pH. In addition, it is noted that the basic pH bleaching gel promoted less postoperative sensitivity (AU).


Introducción: Se sabe que la búsqueda de la estética es algo cada vez más creciente. Entre los procedimientos más populares en odontología estética, se destaca el blanqueamiento dental en consultorio. Ante esto, aún existen pocos estudios que evalúen los efectos de agentes blanqueadores de diferentes pHs sobre la efectividad del blanqueamiento y la sensibilidad dental.Objetivo: Evaluar la sensibilidad dental y la eficacia blanqueadora de geles blanqueadores a base de peróxido de hidrógeno al 35 % con diferentes pH. Metodología: Este es un reporte de tres casos, descriptivo y observacional, del tipo boca partida para cada estrategia de blanqueamiento (gel blanqueador con pH básico y gel blanqueador con pH ácido). Se evaluaron tres pacientes de 25, 26 y 27 años. El registro de color se realizó con la escala clásica VITA y la sensibilidad dental se evaluó con la escala analógica visual.Resultados: Todos los pacientes evaluados presentaron color A3 en el registro de color inicial y, después del blanqueamiento dental, alcanzaron el color A1. Todos refirieron mayor sensibilidad en la hemiarcada derecha (lugar donde se aplicó el gel blanqueador de pH ácido Whiteness HP). Dos pacientes refirieron sensibilidad dental en la hemiarcadaizquierda donde se aplicó el gel blanqueador de pH básico.Conclusiones: Se observala eficacia clínica de los geles blanqueadores de consultorio a base de peróxido de hidrógeno al 35% en cuanto a la estabilidad del color tras el tratamiento blanqueador, independientemente de su pH. Además, se observa que el gel blanqueador de pH básico promovió una menor sensibilidad postoperatoria (AU).


Subject(s)
Humans , Adult , Color , Dentin Sensitivity/complications , Tooth Bleaching Agents/adverse effects , Hydrogen Peroxide , Treatment Outcome , Observational Study , Hydrogen-Ion Concentration
6.
Rev. Flum. Odontol. (Online) ; 1(60): 112-126, jan.-abr. 2023. tab
Article in Portuguese | LILACS, BBO | ID: biblio-1411346

ABSTRACT

A descoloração ou perda de translucidez dos materiais cerâmicos usados em odontologia ainda hoje é um problema, especialmente pelo comprometimento estético. Com o objetivo de comparar a estabilidade de cor, blocos de dissilicato de lítio (IPS e.max CAD HT) e de silicato de lítio reforçado com zircônia (Vita Suprinity HT) fresados no desenho de um disco com dimensões de 1,5 × 7 × 12 mm3 (n = 120) foram preparados usando 3 procedimentos de acabamento de superfície: glaze, polimento mecânico e coloração externa e glaze. Em seguida, cada grupo foi dividido em 2 subgrupos de armazenamento, chá preto e café (n = 10/grupo). As mensurações de cor foram medidas com espectrofotômetro (VITA Easyshade) no estágio inicial e após 1 semana, 2 semanas, 1 mês, 2 meses de armazenamento. As alterações de cor (ΔE) foram calculadas e analisadas estatisticamente usando ANOVA (α < 0,05). Observamos que, para ambos os materiais cerâmicos, o procedimento de glaze apresentou valores de mudança de cor estatisticamente menores do que os outros grupos (p < 0,05) após o armazenamento em ambas as bebidas. Os grupos de dissilicato de lítio apresentaram valores de alteração de cor estatisticamente menores em relação aos grupos de silicato de lítio reforçados com zircônia. Conclui-se que, o glaze sozinho levou a uma maior estabilidade de cor em relação ao polimento mecânico e coloração externa o dissilicato de lítio apresentou maior estabilidade de cor em comparação com o silicato de lítio reforçada com zircônia.


The discoloration or loss of translucency of ceramic materials used in dentistry is still a problem today, especially due to aesthetic compromise. In order to compare color stability, lithium disilicate (IPS e.max CAD HT) and zirconia-reinforced lithium silicate (Vita Suprinity HT) blocks were milled into a disc design with dimensions of 1.5 × 7 × 12 mm3 (n = 120). The specimens were prepared using 3 surface finishing procedures: glaze, mechanical polishing and external staining and glaze. Then, each group was divided into 2 storage subgroups, black tea and coffee (n = 10/group). Color measurements were measured with a spectrophotometer (VITA Easyshade) at the initial stage and after 1 week, 2 weeks, 1 month, 2 months of storage. Color changes (ΔE) were calculated and statistically analyzed using ANOVA (α < 0.05). We observed that, for both ceramic materials, the glaze procedure presented statistically lower color change values ​​than the other groups (p < 0.05) after storage in both beverages. The lithium disilicate groups showed statistically lower color change values ​​than the zirconia-reinforced lithium silicate groups. It is concluded that, glaze alone led to greater color stability compared to mechanical polishing and external staining, lithium disilicate showed greater color stability compared to zirconia-reinforced lithium silicate.


Subject(s)
Beverages , Ceramics , Computer-Aided Design , Color , Dental Polishing/methods , Lithium , Silicates
7.
Psicol. ciênc. prof ; 43: e253492, 2023. graf
Article in Portuguese | LILACS, INDEXPSI | ID: biblio-1440794

ABSTRACT

O racismo é um fenômeno que impacta a vida da população negra, direcionando-a para uma condição de marginalização social, inclusive profissionalmente. Diante disso, o presente estudo, qualitativo, objetivou analisar as estratégias de enfrentamento ao racismo adotadas por universitários negros de uma instituição pública de ensino superior no processo de construção de suas carreiras. Adotando-se como referencial a Teoria de Construção da Carreira, 27 entrevistas semiestruturadas foram conduzidas com graduandos (16 do gênero feminino e 11 do gênero masculino) autodeclarados negros de uma universidade situada na região Sudeste do Brasil. Os dados coletados foram submetidos a Análise de Similitude, por meio do software IRaMuTeQ, que demonstrou, a partir de uma árvore máxima, que os discursos dos participantes estiveram centrados no termo "racismo" e em quatro troncos de similitude relacionados aos vocábulos: "negro", "falar", "situação" e "acontecer". Os resultados indicaram que o racismo é um dos fatores que impactam a carreira dos sujeitos, sobretudo por sustentar práticas discriminatórias veladas e limitar oportunidades profissionais. Em resposta a ele, quatro estratégias de enfrentamento foram identificadas: a) diálogo com sujeitos próximos; b) busca por suporte junto à rede de apoio constituída na universidade; c) denúncia de seus impactos; e d) adoção de ações individuais de transformação da realidade. Os achados permitem identificar a adoção de diferentes estratégias individuais e coletivas de enfrentamento ao racismo, que devem ter seu desenvolvimento estimulado pelas instituições de ensino superior, a fim de que se tornem práticas sistematizadas que favoreçam a discussão sobre o fenômeno em âmbitos acadêmico e profissional.(AU)


The phenomenon of racism impacts the lives of Black population, leading them to social marginalization, including professionally. Thus, this qualitative study analyzes the coping strategies adopted by Black undergraduates from a public higher education institution to confront racism during career construction. Adopting the Career Construction Theory as a framework, 27 semi-structured interviews were conducted (16 women and 11 men) with self-declared black undergraduates from a university located in southeastern Brazil. Similarity analysis of the collected data, performed using the IRaMuTeQ software, showed that, from a maximum tree, the participants' speeches centered around the term "racism" and on four similarity trunks related to the words: "black", "talk", "situation" and "happen". Results indicated that racism majorly impacts the subjects' careers, especially by upholding veiled discriminatory practices and limiting professional opportunities. To cope with it, undergraduates adopt four main strategies: a) dialogue with close subjects; b) search for support with the support network established at the university; c) denunciation of its impacts; and d) adoption of individual strategies to transform reality. The findings point to different actions, individual and collective, adopted to fight racism, whose development should be supported by higher education institutions so that they become systemic practices that favor discussing the phenomenon in academic and professional fields.(AU)


El racismo es un fenómeno que impacta la vida de la población negra, llevándola a una condición de marginación social, incluso a nivel profesional. Así, este estudio cualitativo, tuvo por objetivo analizar las estrategias de afrontamiento el racismo que utilizan los universitarios negros de una Institución Pública de Educación Superior en el proceso de construcción de sus carreras. Tomando como referencia la Teoría de Construcción de Carrera, se realizaron 27 entrevistas semiestructuradas a estudiantes (16 mujeres y 11 hombres) autodeclarados negros de una universidad en la región Sureste de Brasil. Los datos recolectados se sometieron a un Análisis de Similitud, desarrollado utilizando el software IRaMuTeQ, que demostró, a partir de un árbol máximo, que los discursos de los participantes se centraron en el término "racismo" y en cuatro troncos de similitud relacionados con las palabras: "negro", "hablar", "situación" y "pasar". Los resultados indicaron que el racismo es uno de los factores que impactan la carrera, especialmente por sostener prácticas discriminatorias veladas y limitar las oportunidades profesionales. En respuesta a ello, se identificaron cuatro estrategias de afrontamiento: a) diálogo con sujetos cercanos; b) búsqueda de apoyo en la red constituida en la universidad; c) denuncia de sus impactos; y d) adopción de acciones individuales para transformar la realidad. Los hallazgos permiten identificar la adopción de diferentes estrategias, individuales y colectivas, para enfrentar el racismo, las cuales deben tener su desarrollo estimulado por las instituciones de educación superior, para que se conviertan en prácticas sistematizadas que favorezcan la discusión del fenómeno en el ámbito académico y profesional.(AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Young Adult , Students , Universities , Adaptation, Psychological , Career Choice , Career Mobility , Racism , Poverty , Prejudice , Problem Solving , Psychology , Psychology, Social , Public Policy , Race Relations , Rejection, Psychology , Salaries and Fringe Benefits , Self Concept , Social Behavior , Social Change , Social Class , Social Identification , Social Justice , Social Problems , Social Sciences , Socialization , Societies , Socioeconomic Factors , Stereotyping , Awareness , Work , Ethnicity , Family , Mental Health , Surveys and Questionnaires , Color , Cultural Diversity , Crime , Cultural Characteristics , Culture , Personal Autonomy , Dehumanization , Qualitative Research , Racial Groups , Education , Emotions , Employee Incentive Plans , Resilience, Psychological , Altruism , Bullying , Social Stigma , Social Discrimination , Genocide , Enslavement , Protective Factors , Social Capital , Physical Appearance, Body , Work Performance , Social Segregation , Political Activism , Work Engagement , Ethnocentrism , Extremism , Social Oppression , Freedom , Respect , Empowerment , Sociodemographic Factors , Ethnic and Racial Minorities , Social Vulnerability , Citizenship , Diversity, Equity, Inclusion , Antiracism , Hate , Hierarchy, Social , Household Work , Human Rights , Learning , Minority Groups
8.
Pesqui. bras. odontopediatria clín. integr ; 23: e210147, 2023. tab, graf
Article in English | LILACS, BBO | ID: biblio-1431045

ABSTRACT

Abstract Objective: To determine the effect of ozonated water on the color stability of denture tooth and denture bases. Material and Methods: Thirty denture base discs consisting of 15 Acropars and 15 ProBase Hot specimens with the dimensions of 40 × 5 mm were prepared. Fifteen denture teeth in shade A1 (Ivoclar Vivadent, Schaan, Liechtenstein) were mounted in a specific acrylic jig. All specimens were immersed in three solutions (1% sodium hypochlorite, ozonated water, and distilled water) for four months (one year of clinical use). Color measurements were done with a spectrophotometer and assessed using the CIE L*a*b* colorimetric system (0, 4, 8, 12, and 16 weeks). Data were analyzed using the three-way ANOVA and Tukey test (α=0.05). Results: Tukey's post hoc test revealed a significant change in color in the Acropars denture base for the distilled water group compared to the ozonated water and 1% hypochlorite (p<0.05). Regarding the ProBase Hot denture base, significantly less color change was observed in the 1% hypochlorite group compared to the ozonated water and distilled water (p≤0.001). For the denture teeth, significantly less color change was seen in the distilled water group than in the ozonated water (p=0.015) and 1% hypochlorite (p<0.05) groups. Conclusion: The color change of denture bases and denture tooth in ozonated water are acceptable. Ozonated water can be considered a good disinfectant for cleaning dentures.


Subject(s)
Ozone/therapeutic use , Color , Dental Polishing , Denture, Complete , Acrylic Resins , Distilled Water , Analysis of Variance , Denture Cleansers/adverse effects , Polymerization
9.
Braz. dent. sci ; 26(2): 1-11, 2023. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1425563

ABSTRACT

Objective: The present study aims to evaluate the color stability and degree of conversion of amine-free dual cured resin cement compared to light cured and amine-containing dual cured resin cements used with two different translucencies of thin esthetic restorations. Material and Methods: A total of 120 specimens were prepared for color stability testing (n=60). The specimens were divided into three main groups according to the resin cement type. Group 1: amine-free dual cured, Group 2: light cured, Group 3: amine-containing dual cured. Each group was further subdivided according to the ceramic translucency into two subgroups: high and low translucency. Color stability was assessed by a spectrophotometer before and after thermal aging. For the degree of conversion assessment (n=60), Fourier transform infrared spectroscopy was used at three different time intervals. Statistical analysis was performed using multi-factorial ANOVA, followed by one-way ANOVA with Bonferroni correction. Results: Amine-containing resin cement showed significantly higher ΔEab and ΔE00in both translucencies (4.5±0.3, 3.5±0.3 respectively for high translucency ceramic and 3.8±0.4, 3.0±0.3 respectively for low translucency) than the other tested cements (p<0.001). The highest degree of conversion (DC) was shown after 2 weeks by the amine-free dual cured resin cement (86.27±0.74). Conclusion: Amine-free dual cured resin cement can be an alternative to light cured one for cementation of thin veneers since it showed comparable color stability and high degree of conversion (AU)


Objetivo: O presente estudo tem como objetivo avaliar a estabilidade de cor e o grau de conversão do cimento resinoso dual sem amina em comparação com cimentos resinosos fotopolimerizáveis contendo amina usados com duas translucidezes diferentes em restaurações estéticas definitivas. Material e Métodos: Um total de 120 espécimes foram preparados para teste de estabilidade de cor (n=60). Os espécimes foram divididos em três grupos principais de acordo com o tipo de cimento resinoso. Grupo 1: polimerização dupla sem amina, Grupo 2: fotopolimerização, Grupo 3: polimerização dupla contendo amina. Cada grupo foi ainda subdividido de acordo com a translucidez da cerâmica em dois subgrupos: alta e baixa translucidez. A estabilidade da cor foi avaliada por um espectrofotômetro antes e após o envelhecimento térmico. Para a avaliação do grau de conversão (n=60), a espectroscopia de infravermelho com transformada de Fourier foi usada em três intervalos de tempo diferentes. A análise estatística foi realizada usando ANOVA multifatorial, seguida de ANOVA um faot com correção de Bonferroni. Resultados: O cimento resinoso contendo amina apresentou ΔEab e ΔE00 significativamente maiores em ambas as translucidezes (4,5±0,3, 3,5±0,3 respectivamente para cerâmica de alta translucidez e 3,8±0,4, 3,0±0,3 respectivamente para baixa translucidez) do que os outros cimentos testados (p< 0,001). O maior grau de conversão (DC) foi mostrado após 2 semanas pelo cimento resinoso dual sem amina (86,27±0,74). Conclusão: O cimento resinoso dual sem amina pode ser uma alternativa ao cimento polimerizável na restauração de facetas finas, uma vez que apresentou estabilidade de cor comparável e alto grau de conversão. (AU).


Subject(s)
Color , Resin Cements , Polymerization , Lithium
10.
Braz. j. oral sci ; 22: e238082, Jan.-Dec. 2023. tab
Article in English | LILACS, BBO | ID: biblio-1393422

ABSTRACT

Aim: To determine if the artificial staining with black tea (BT) influences the enamel microhardness before in-office bleaching and if BT staining is necessary to evaluate the efficacy of bleaching with 35% hydrogen peroxide Methods: Enamel/dentin blocks were randomized into groups according to the staining protocol (n=5/group): (CO) control ­ maintained in artificial saliva solution (AS); (BT4) immersed in black tea solution for 4 h; (BT24) immersed in black tea solution for 24 h. After the staining protocols, all specimens were kept in AS for one week, followed by bleaching (three sessions of HP application for 40 min). Knoop surface microhardness (kgF/mm2) was determined at baseline (T0), after staining (T1), after 7 days of storage in AS (T2), and after bleaching (T3). The color (∆E00) and coordinate changes (∆L, ∆a, ∆b) were measured using a digital spectrophotometer at T0 and T3. Data were submitted to one-way (∆E00, ∆L, ∆a, ∆b) or two-way ANOVA repeated measures (kgF/mm2) and Tukey's test (a=5%). Results: The staining protocols (BT4 and BT24) promoted significantly lower microhardness (T1 and T2, p<0.05) than CO, whereas CO was the only group to maintain microhardness values over time. Bleaching promoted perceptible ∆E00 without a significant difference among the groups regardless of the staining protocol (p=0.122). CO and BT4 showed no differences in terms of ∆L and ∆a (p>0.05), but BT4 displayed a higher ∆b than CO. Conclusion:The artificial staining with BT negatively affected the enamel surface microhardness and was not essential to evaluate the efficacy of 35% hydrogen peroxide bleaching


Subject(s)
Staining and Labeling , Tea/adverse effects , Tooth Bleaching , Color , Dental Enamel , Bleaching Agents , Hardness Tests , Hydrogen Peroxide
11.
West China Journal of Stomatology ; (6): 190-196, 2023.
Article in English | WPRIM | ID: wpr-981111

ABSTRACT

OBJECTIVES@#This study aimed to observe the color rebound and rebound rates of non-pulp discolored teeth within 1 year after routine internal bleaching to guide clinical practice and prompt prognosis.@*METHODS@#In this work, the efficacy of bleaching was observed in 20 patients. The color of discolored teeth was measured by using a computerized colorimeter before bleaching; immediately after bleaching; and at the 1st, 3rd, 6th, 9th, and 12th months after bleaching. The L*, a*, and b* values of the color of cervical, mesial, and incisal parts of the teeth were obtained, and the color change amounts ΔE*, ΔL*, Δa*, and Δb* were calculated. The overall rebound rate (P*) and the color rebound velocity (V*) were also analyzed over time.@*RESULTS@#In 20 patients following treatment, the average ΔE* of tooth color change was 14.99. After bleaching, the neck and middle of the teeth ΔE* and ΔL* decreased in the 1st, 3rd, 6th, 9th, and 12th months, and the differences were statistically significant. Meanwhile, from the 9th month after bleaching, the rebound speed was lower than that in the 1st month, and the difference was statistically significant. The incisal end of the tooth ΔE* and ΔL* decreased in the 6th, 9th, and 12th months after bleaching, and the differences were statistically significant. No significant difference was found in the rebound speed between time points. However, this rate settled after the 9th month, with an average color rebound rate of 30.11% in 20 patients.@*CONCLUSIONS@#The results indicated that internal bleaching could cause a noticeable color change on pulpless teeth. The color rebound after bleaching was mainly caused by lightness (L*), which gradually decreased with time, and it was slightly related to a* and b*. The color of the teeth after internal bleaching rebounded to a certain extent with time, but the color rebound speed became stable from the 9th month. Clinically, secondary internal bleaching can be considered at this time according to whether the colors of the affected tooth and the adjacent tooth are coordinated and depending on the patient's needs.


Subject(s)
Humans , Tooth Bleaching/methods , Tooth, Nonvital/drug therapy , Color , Tooth Discoloration/drug therapy , Tooth , Hydrogen Peroxide/therapeutic use , Tooth Bleaching Agents/therapeutic use
12.
Braz. j. oral sci ; 22: e230282, Jan.-Dec. 2023. tab
Article in English | LILACS, BBO | ID: biblio-1510253

ABSTRACT

Aim: Evaluate the roughness, microhardness and color change of different Bulk Fill resins when submitted to the condition of gastroesophageal reflux and bulimia. Methods: 60 specimens (n = 10) of Bulk-Fill composite resins were made: M1 ­ Filtek™; M2 ­ Tetric N-Ceram and M3 ­ OPUS, through a matrix 2x6 mm and light cured by the VALO light source. After polishing, initial analyzes (48 hours - T0) of surface roughness (Ra), microhardness (VHN) and color change (ΔE) were performed. To simulate the oral condition of severe gastroesophageal reflux and bulimia, the specimens were immersed in hydrochloric acid (S1) (pH 1.7) 4 minutes a day, for 7 days. Control group specimens were immersed in artificial saliva (S2). Subsequently to immersions, mechanical brushing was performed for 3 minutes, three times a day, simulating 7 days of brushing. And again, the analyzes of Ra, VHN and ΔE were performed (7 days - T1). Thus, hydrochloric acid immersion, mechanical brushing and Ra analysis were repeated at 14 days (T2) and 21 days (T3); and T2, T3 and T4 (3 years) for VHN and ΔE. Results: After Shapiro-Wilk statistical test, ANOVA and Tukey test with Bonferroni adjustment (p>0.05), M3 showed the lowest Ra at all times compared to the other resins, while the highest Ra was at T0. M1 and T1 showed higher VHN. And M2 and T4 showed higher ΔE. Conclusion: Bulk Fill resins can be indicated for patients with Gastroesophageal Reflux and Bulimia, nonetheless, Tetric N-Ceram resin showed the worst results


Subject(s)
Color , Composite Resins , Hardness , Hydrochloric Acid , Gastroesophageal Reflux , Bulimia
13.
Braz. j. oral sci ; 21: e225946, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1384159

ABSTRACT

Aim This study aims to evaluate and validate the sensibility and the level of agreement between different gingival color measures obtained by a spectrophotometer (SPECTRO) and a photography (PHOTO) method. Methods Among 40 patients, the color was measured 2 mm apical to the gingival margin by CIE L*, a*, b* system using a reflectance spectrophotometer and the photography's plus software. The level of agreement between three different measures (m1, m2, m3) in parameters L*, a*, b*, and ∆E (color variation) was evaluated by random and systematic errors, as well as the limits and coefficient of concordance. A comparison between the methods was performed by the Bland-Altman test and the sensibility level was evaluated accordingly to the ∆E: 3.7 thresholds with p<0.05 as the level of significance for these comparisons. Results The SPECTRO method has not presented the systematic error (p>0.05) and had reproducibly and agreement level in three variable measures L* (r: 0.6), a* (r: 0.3), and b* (r: 0.5) as to the PHOTO method L* (r: 0.6), a* (r: 0.5), and b* (r: 0.5), which presented systematic error in L* values (p<0.05). The means of ∆E between measurements were: 6.5 SPECTRO and 5.9 PHOTO. There was no good level of sensitivity ∆E> 3.7 and agreement between the methods, mainly for the a* values. On the other hand, for the L* and in for the most comparisons of b* values, the level of agreement was higher. Conclusion Both methods could quantify the gingival color from the coordinates L *, a *, and b *, which has shown greater reliability between the measurements acquired by the SPECTRO method.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Spectrophotometers , Color , Photography, Dental , Gingiva , Incisor
14.
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
15.
Braz. j. oral sci ; 21: e222812, jan.-dez. 2022. tab
Article in English | LILACS, BBO | ID: biblio-1348712

ABSTRACT

Aim: To evaluate the influence of the parameters L* a* b* on the variation of the color of bovine tooth enamel submitted to artificial darkening, after simulated brushing, with whitening toothpastes containing blue covarine. Methods: To undertake this study in vitro, 60 specimens (SP) were divided into 6 groups (n=10): control group (CGwater) and 5 test groups (GT1-Colgate Total 12, GT2-Oral-B 3D White Perfection, GT3- Colgate Luminous Instant White, GT4-CloseUp White Diamond Attraction, GT5-Sorriso Xtreme White). The specimens were darkened with coffee and submitted to simulated brushing for 6, 12, and 24 months. The alteration in the color was evaluated using CIELAB parameters and the ΔL, Δa, Δb and ΔE were calculated. The data was analyzed through generalized linear models using the R program and considering a level of significance of 5%. Results: The parameters L*, a* and the ΔL, Δa obtained better results in the test group than in the control group. There were no statistical differences between CG and the test groups for the evaluation of the b* parameter. In the evaluation of the Δb, the GT3 differed statistically from the CG. In relation to the ΔE, all the group tests showed a variation in color statistically greater than that of the CG and the GT4 showed the greatest variation, not differing from the GT3 during the periods studied. Conclusion: The mechanical and optical whitening agents positively influenced the values L*a* and b*, as well as in its variations and in the ΔE. It is important to emphasize, however, that to analyze tooth whitening it is necessary to evaluate their parameters together


Subject(s)
Tooth , Toothpastes , Color , Bleaching Agents
16.
Arch. latinoam. nutr ; 72(3): 185-195, sept. 2022. tab
Article in English | LILACS, LIVECS | ID: biblio-1399261

ABSTRACT

Introduction: Rice is a staple food in Costa Rica representing almost 24 % of the total calorie intake in the diet. Consumers have become more quality conscious about the rice consumed, so producers need to focus on the quality of rice along with production. Objective: The aim of this study was to investigate the physicochemical profile and consumer preference of five Costa Rican rice varieties: Palmar 18, Basmatico, Chin Chin, INTA-Miravalles, and CR- 5272. Materials and methods: Proximate analysis, amylose, and mineral content were performed in the raw grain. Two different sessions were performed (n=120 each) to evaluate consumer preference measurements using the John Brown R-Index (RJB) index. The first sensory panel selected the best cooking preparation and the second, the preferred rice variety. Instrumental color measurements (L*, C*, hº, DE) were applied to the cooked rice varieties (76-96ºC for 38 min). Results: Regarding the physicochemical characterization, INTAMiravalles showed the highest protein content (8.2%), while Basmatico and Chin Chin, the lowest. Four varieties presented high amylose content (AC) and INTA-Miravalles reported an intermediate AC. The mineral content varied among varieties. INTA-Miravalles showed the highest N, followed by Palmar 18. The cooking preparation from the regulatory agency was preferred by consumers. The consumers' preference of the varieties ranked from high to low: Basmatico>Chin Chin=CR5772>Palmar 18=INTA-Miravalles. Conclusions: This study suggests that consumer preference for cooked rice was influenced by physicochemical characteristics such as protein, AC, mineral content, and aromatic attributes. Consumer acceptance is an important factor to consider when new varieties are developed. The water-to-rice ratio during cooking played an important role in cooked rice sensory quality(AU)


Introducción: el arroz es un alimento básico de consumo en Costa Rica que representa casi el 24% de la ingesta total de calorías en la dieta. Los consumidores se han vuelto más conscientes de la calidad del arroz que consumen, por lo que los productores deben enfocar esfuerzos en la calidad y producción del arroz. Objetivo: El objetivo de este estudio fue investigar el perfil fisicoquímico y la preferencia del consumidor de cinco variedades de arroz de Costa Rica: Palmar 18, Basmatico, Chin Chin, INTA-Miravalles y CR-5272. Materiales y métodos: Se realizó el análisis proximal, contenido de amilosa (CA) y de minerales en el grano crudo y color instrumental en el arroz cocido. Se realizaron dos mediciones de preferencia de los consumidores (n=120) utilizando el índice R de James Brown (RJB). En la primera se seleccionó el mejor método de preparación y en la segunda, la variedad de arroz preferido. El color instrumental (L*, C*, hº, DE) se midió a las variedades de arroz cocinado (76-96ºC por 38 min). Resultados: Miravalles mostró el mayor contenido en proteínas (8,2%), mientras que Basmatico y Chin Chin, el menor. Cuatro variedades presentaron un alto CA y el INTAMiravalles reportó un CA intermedio. El contenido mineral varió entre las variedades. INTA-Miravalles mostró el mayor contenido de nitrógeno, seguido de Palmar 18. El método de cocción del ente regulador fue el preferido por los consumidores. La preferencia de los consumidores por las variedades de mayor a menor fue: Basmatico > Chin Chin = CR5772 > Palmar 18 = INTA-Miravalles. Conclusiones: La preferencia de los consumidores por el arroz cocido se vio influenciada por características fisicoquímicas como proteína, CA, minerales y atributos aromáticos. La aceptación de los consumidores es un factor importante cuando se desarrollan nuevas variedades. La relación agua/ arroz durante la cocción desempeñó un papel importante en la calidad del arroz cocido(AU)


Subject(s)
Humans , Adolescent , Adult , Middle Aged , Aged , Young Adult , Oryza/chemistry , Consumer Behavior , Eating , Smell , Color , Costa Rica , Food Handling , Amylose/analysis , Minerals/analysis
17.
J. oral res. (Impresa) ; 11(4): 1-11, jul. 21, 2022. ilus, tab
Article in English | LILACS | ID: biblio-1426955

ABSTRACT

Aim: This study aims to evaluate the surface roughness and susceptibility to staining of bleached composite resin with 22% carbamide peroxide, as well as the effect of subsequent prophylaxis with NaHCO3 powder. Material and Methods: Forty disk-shaped (2 × 6 mm) specimens of composite resin (Z250 XT) were prepared. Half of the specimens were subjected to bleaching with 22% carbamide peroxide, and the other half were stored in artificial saliva. In sequence, all specimens were immersed in acai juice (Euterpe oleracea) for 4 h for 14 days, and subdivided into two groups. Group 1 samples were subjected to prophylaxis treatment, while group 2 samples were subjected to treatment with artificial saliva. Surface roughness (Ra) and color (ΔE*) were measured after polishing (T0), bleaching (T1), immersion in acai juice (T2), and application of NaHCO3 powder (T3) using a profilometer and a spectrophotometer. Results: Statistical analyses (analysis of variance and Tukey's test, p≤0.05) revealed that regarding color there was statistically significance for the factors in isolation, except for the factor bleaching. For both color and surface roughness there was statistically significant difference for the interaction, except for the interaction between NaHCO3 power and bleaching. Conclusion: The NaHCO3 air-powder polishing decreases the staining of the composite resin; however, it increases the surface roughness. With respect to the color variable, the whitening factor had no significant effect on the tested material; however, it increases surface roughness.


Objetivo: Este estudio tiene como objetivo evaluar la rugosidad de la superficie y la susceptibilidad a la tinción de la resina compuesta blanqueada con peróxido de carbamida al 22%, así como el efecto de la profilaxis posterior con polvo de NaHCO3. Material y Métodos: Se prepararon cuarenta especímenes en forma de disco (2 × 6 mm) de resina compuesta (Z250 XT). La mitad de los especímenes se sometieron a blanqueo con peróxido de carbamida al 22% y la otra mitad se almacenó en saliva artificial. En secuencia, todos los especímenes se sumergieron en jugo de acai (Euterpe oleracea) durante 4h durante 14 días, y se subdividieron en dos grupos. Las muestras del grupo 1 se sometieron a tratamiento profiláctico, mientras que las muestras del grupo 2 se sometieron a tratamiento con saliva artificial. La rugosidad de la superficie (Ra) y el color (ΔE*) se midieron después del pulido (T0), el blanqueo (T1), la inmersión en jugo de acai (T2) y la aplicación de polvo de NaHCO3 (T3) utilizando un perfilómetro y un espectrofotómetro. Resultados: Los análisis estadísticos (análisis de varianza y prueba de Tukey, p≤0.05) revelaron que en relación al color hubo significancia estadística para los factores en forma aislada, excepto para el factor blanqueamiento. Tanto para el color como para la rugosidad de la superficie hubo una diferencia estadísticamente significativa para la interacción, excepto para la interacción entre el poder de NaHCO3 y el blanqueo. Conclusión: El pulido al aire con polvo de NaHCO3 disminuye el manchado de la resina compuesta; sin embargo, aumenta la rugosidad de la superficie. Con respecto a la variable color, el factor de blanqueamiento no tuvo efecto significativo sobre el material ensayado; sin embargo, aumenta la rugosidad de la superficie.


Subject(s)
Humans , Sodium Bicarbonate , Composite Resins/chemistry , Saliva , Brazil , Color , Dental Prophylaxis/methods , Euterpe , Immersion
18.
São Paulo; s.n; 20220720. 105 p.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1379535

ABSTRACT

O intuito do presente estudo foi avaliar o efeito de laminados cerâmicos de dissilicato de lítio e cimentos resinosos com cor para mascarar diferentes substratos e a compatibilidade de cor das pastas try-in. Foram produzidos 120 laminados cerâmicos de dissilicato de lítio na cor B1 com 0,5 mm de espessura em três diferentes níveis de translucidez: HT, MT e LT (Emax CAD Ivoclar); cimentados com cimento resinoso (Allcem Veneer FGM) nas cores Opaque White (OW) e Trans (TRANS), com espessura de cimentação de 100 micrômetros, em substratos de resina composta (Opallis FGM) de 3mm (1mm esmalte e 2mm dentina), com saturações opostas: A1 e A4, totalizando 12 grupos (n=10). Os espécimes foram submetidos à análise de cor por meio de um espectrofotômetro e as leituras feitas em oito diferentes tipos: laminados, substratos, prova seca, prova úmida, try-in, cimento resinoso não polimerizado, polimerizado imediato (T0) e polimerizado após 24 horas (T24). A partir dessas leituras foram obtidos os valores L*, a* e b* de reflectância, calculada a diferença de cor (E00) e o parâmetro de translucidez (PT). Para interpretação foram utilizados limites de perceptibilidade (LP) e aceitabilidade (LA) de diferença de cor sendo E00 = 0.8 o LP e E00 = 1.8 o LA. As diferenças de cores entre a pasta try-in e o cimento polimerizado em T0 e T24; e do cimento resinoso polimerizado imediato (T0) e após 24 horas (T24) mantiveram abaixo do LA e analisadas pelo teste de Kruskal Wallis não foram encontradas diferenças estatisticamente significativas (p>0.05). Os valores de E00 obtidos entre as cores de cimento resinoso nas cerâmicas HT e MT mantiveram acima do LA e nas LT abaixo do LA e acima do LP, e analisados por ANOVA não foram encontradas diferenças entre eles (p>0.05). Na comparação de cor entre os substratos (A1 e A4) os valores de E00 mantiveram acima do LA, com uma menor diferença na cerâmica LT, comprovada pelo teste de Kruskal Wallis (p=0.000) e Dunn. Para os valores de E00 obtidos da diferença entre a prova úmida com a cor final da restauração, foi realizado teste de Kruskall Wallis e Dunn, que identificaram diferenças (p=0.0001) entre HTTRANS e HTOW em T0, HTOW em T0 com todos os grupos de LT e HTOW em T24 e LTTRANS e LTOW em T0 no substrato de cor A1 e diferenças entre os grupos (p=0.000) HTOW em T0 e T24 e LTOW em T0 no substrato de cor A4. No parâmetro de translucidez (PT) foi realizado o teste de Mann-Whitney. Para o substrato A1, existiu diferença entre os grupos (p=0.0028) onde HT-TRANS se apresenta com maior translucidez, e no substrato A4 o teste não apontou diferença entre os grupos (p>0.05). Pode-se concluir que as cores das pastas try-in são fiéis aos seus cimentos polimerizados e que existe estabilidade de cor da restauração nas primeiras 24 horas. A cor do substrato é a principal variável na translucidez da restauração com laminados ultrafinos e a translucidez da cerâmica é o fator chave na capacidade de mascaramento de diferentes cores de substratos.


Subject(s)
Substrates for Biological Treatment , Color
19.
São Paulo; s.n; 20220720. 110 p.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1379734

ABSTRACT

Este estudo tem como objetivo avaliar a influência de um gel clareador de peróxido de carbamida à 16% (Whiteness Perfect, FGM, Joinville, SC, Brasil) associados a biomateriais (Biosilicato® ou biovidro F18®), na alteração de cor e microdureza do esmalte e dentina de dentes bovinos. Um espectrofotômetro odontológico (VITA Easyshade Compact, Vident, Brea, CA, USA) foi utilizado para obter as coordenadas de cor (L*, a*, b*), e diferença de cor foi avaliada através do sistema CIELAB (Eab), CIEDE2000 (E00) e índice de clareamento (WID). Foram selecionados123 dentes bovinos, cor A2 e seccionados usando uma máquina de corte (Isomet 1000, Buehler Ltd, Lake Bluff, IL, EUA). foram seccionados transversalmente 63 desses dentes, com uma porção de esmalte e dentina, para o teste de microdureza (microdureza Knoop), com espessura de 4mm, e divididos, por sorteio, em 3 grupos (n=21); 60 dentes foram preparados para a avaliação da mudança de cor (métodos CIELAB, CIEDE2000 e WID), cortados em fragmentos de 7mm X 7mm X 4mm, e divididos, por sorteio, em 3 grupos (n=20). Todos os fragmentos foram embutidos em tubos de PVC (policloreto de vinila) com auxílio de resina acrílica quimicamente ativada (Jet, Artigos Odontológicos Clássico Ltda, Brasil) resultando em corpos de prova de 15mm de altura e 20mm de diâmetro. Tanto o teste de microdureza quanto as medições de cor foram realizados incialmente. Para o grupo controle, os espécimes receberam tratamento clareador com gel clareador de peróxido de carbamida 16%; para o grupo Biosilicato, os espécimes receberam o tratamento clareador associado ao Biosilicato® a 2%; e para o grupo F18®, os espécimes receberam tratamento clareador associado ao biovidro F18 a 2%. O gel foi aplicado na superfície na quantidade de 0,06 gramas no grupo controle e 0,06 gramas mais 2% de material bioativo para os outros dois grupos, pesados com balança analítica de precisão (Adventurer Pro Analytical Balance 260g, Ohaus Corporation, New Jersey, EUA). O gel foi aplicado diariamente, por 8 horas, durante 14 dias consecutivos, conforme orientação do fabricante. Diariamente, ao final do tempo de aplicação, o gel era removido e os espécimes eram imersos em saliva artificial e armazenados a 37°C. Após o tratamento clareador, foram realizadas novas medidas de microdureza e cor. Os resultados de microdureza Knoop em esmalte e dentina, coordenadas de cor (L*, a*, b*) e o índice de clareamento inicial e final (WID inicial e final) foram submetidos à ANOVA de medidas repetidas de dois fatores, seguida do teste de Tukey para contraste de média (= 0,05). As medidas de diferença de cor de Eab, E00 e variação do índice de clareamento (WID) foram submetidas a ANOVA de medidas repetidas de um fator. Para o grupo controle houve redução estatisticamente significativa nos valores de microdureza do esmalte após o tratamento clareador (p<0,05). Os grupos Biosilicato® e F18® tiveram aumento estatisticamente significativo na microdureza Knoop (p<0,05), quando comparados aos seus valores antes do tratamento. Em relação à dentina, houve, no grupo controle, redução estatisticamente significativa da microdureza após o tratamento clareador (p<0,05), o que também foi observado para os grupos associados ao Biosilicato® e F18®. O grupo de tratamento associado ao Biosilicato® obteve a menor diminuição no valor de microdureza Knoop em dentina, seguido do tratamento associado ao F18®. O grupo controle, por outro lado, teve a maior diminuição da microdureza, sendo estatisticamente diferente dos demais (p<0,05). Em relação aos parâmetros de luminosidade (L*), a* e b*, todos os grupos tiveram aumento estatisticamente significante no valor quando comparados aos valores iniciais (p<0,05). Quanto à diferença de cor, os três grupos apresentaram Eab sem diferença estatisticamente significante entre eles (p>0,05). Em relação ao índice de clareamento, após o tratamento clareador, os três grupos tiveram aumento significativo do WID, que foi estatisticamente diferente dos valores iniciais (p<0,05). Ao comparar o fator grupo, os três tipos de tratamento não apresentaram diferença estatisticamente significante no WID final (p>0,05). Diante disso, o uso de materiais bioativos associados a um agente clareador reduz os efeitos negativos do tratamento, sem diminuir sua eficácia clareadora


Subject(s)
Tooth Bleaching , Color
20.
Int. j interdiscip. dent. (Print) ; 15(1): 97-99, abr. 2022. ilus
Article in English | LILACS | ID: biblio-1385259

ABSTRACT

ABSTRACT: Nowadays, maxillary midline diastema (MMD) can be treated with different multidisciplinary approaches. When restorative dentistry is needed, glass-matrix ceramic materials is one of the best choices, since they present good optical behavior and high survival rates in the anterior dentition. To obtain an adequate interphase, and color integration are one of the main restorative goals, and for that purpose, specific finishing and polishing procedures must be employed to avoid staining and ensure the restoration's color stability. In the case report presented in this article, a single lithium disilicate ceramic fragment was performed to close a MMD produced by the shape alteration of one of the maxillary central incisors. Also, the finishing and polishing procedure is discussed.


Subject(s)
Humans , Female , Adult , Ceramics , Color , Dentistry , Diastema
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