Materiais restauradores em odontopediatria: preferência de pais e crianças e análise bibliométrica-altimétrica / Restorative materials in pediatric dentistry: children's and adults' preference and bibliometric-altmetric analysis

Atualmente, diversos materiais restauradores encontram-se disponíveis para aplicabilidade em Odontopediatria. Os avanços dos materiais restauradores conduzem à necessidade de novos estudos nessa temática. O presente estudo apresenta duas propostas de investigação: 1) Estudo transversal com objetivo de avaliar a preferência de pais/responsáveis e crianças quanto ao emprego do compômero colorido (Twinky Star®, Voco, Alemanha); 2) Estudo bibliométrico altimétrico com objetivo de analisar 50 artigos mais citados referente aos materiais restauradores utilizados em Odontopediatria e o alcance dessa informação científica nas mídias on-line. O estudo transversal envolveu 260 pares de pais/responsáveis e crianças de 5 a 11 anos de idade de dois serviços de saúde da região metropolitana de Belo Horizonte-MG. Exame quanto à cárie dentária foi realizado por examinadora calibrada para o critério da Organização Mundial da Saúde. Um manequim odontológico contendo restaurações com compômeros coloridos e materiais convencionais (resina composta, ionômero de vidro e amálgama) foi apresentado aos participantes do estudo e realizou-se inquérito sobre a preferência dos materiais dentários. O Questionário de Estilo e Dimensões dos Pais (PSDQ) e o Eysenck Personality Questionnaire Junior (EPQ-J) foram aplicados, este último apenas para pais/responsáveis de crianças de 5 e 6 anos de idade. Análises descritivas, bivariadas e regressão multivariada de Poisson foram realizadas. A maioria dos pais/responsáveis (74,2%) preferiu materiais convencionais. A idade da criança (p=0,006), a renda familiar (p= 0,001) e o nível de escolaridade (p< 0,001) associaram se a essa escolha. A análise multivariada demonstrou que crianças menores de 7 anos apresentaram 1,20 vezes maior probabilidade de escolher compômeros coloridos do que seus pares mais velhos (p< 0,001), assim como pais/responsáveis com menos de 11 anos de escolaridade e cujos filhos eram menores de 7 anos apresentaram 2,17 e 1,74 maior probabilidade para escolher compômeros coloridos, respectivamente. Concluiu-se que responsáveis com maior escolaridade apresentaram maior resistência às restaurações coloridas e crianças menores de 7 anos aceitaram melhor este material. O estudo bibliométrico-altimétrico adotou estratégia de busca em três bases (Web of Science, Scopus e Google Scholar), independente da data de publicação. Após seleção dos artigos por um grupo de cinco pesquisadores, em março de 2023, foram incluídos estudos que avaliassem qualquer material restaurador empregado em dentes decíduos e analisados dados referentes ao título, número de citações, país/continente, autoria, periódico, instituição, desenho do estudo, tipo de material restaurador, e escore altimétrico. Os artigos, publicados entre 1991 a 2002, apresentaram variação de citações de 19 a 113. Os autores com maior número de citações foram Qvist V e Teglers PT. O estudo experimental foi o principal delineamento de estudo observado e o cimento de ionomero de vidro foi o material mais reportado. A Europa foi o continente, e o Brasil, o país com maior número de citações. O escore altimétrico esteve presente em 23 artigos, com ênfase para dois artigos (43/6º e 73/7º). Concluiu-se que o cimento de ionômero de vidro foi o material mais estudado. Ficou evidente o distanciamento entre a posição dos trabalhos nas análises bibliométrica e altimétrica, apontando necessidade de disseminação da informação além dos círculos acadêmicos.

Currently, an arsenal of restorative materials is available for applicability in pediatric dentistry. The advances in restorative materials conducted to need for further studies in this thematic. The present study presents two investigation proposals: 1) Cross-sectional study aiming to evaluate the preference of parents and children regarding the use of colored compomer (Twinky Star®, Voco, Germany); 2) Bibliometric-altmetric study aiming to analyze the 50-most cited papers regarding to restorative materials used in pediatric dentistry and the dissemination of scientific information in online media. The cross-sectional study included 260 pairs of caregivers/children aged 5 to 11, in two public health services, in the metropolitan region of Belo Horizonte-MG. Examination for dental caries was performed by an examiner calibrated to the criteria of the World Health Organization. A dental mannequin containing colored compomers restorations and conventional materials (composite resin, glass ionomer cement and dental amalgam) was presented to the population and a survey was conducted about the preference of dental materials. Parents' Style and Dimensions Questionnaire (PSDQ) and Eysenck Personality Questionnaire Junior (EPQ-J) were applied, the last one only for parents/caregivers of children aged 5 to 6. Descriptive, bivariate and Poisson regression analyzes were performed. Most adults (74.2%) preferred conventional materials. Family income (p= 0.001) and education level (p< 0.001) were associated with its choice. Age up to 7 (p< 0.001) associated with children's choice for colored restorations (72.3%). Children younger than 7 had 1.20 higher probability to choose colored compomers than their older pairs, while adults with children younger than 7 and less than 11 years of schooling had 1.74 and 2.17 higher probability to choose colored compomers, respectively. It was concluded that caregivers with higher educational level showed greater resistance to use of colored restorations and children younger than 7 had better acceptance of colored material. The bibliometrics-altmetrics study adopted a search strategy in three databases (Web of Science, Scopus and Google Scholar), independent of the year of publication. After selection of papers by a panel of five researchers, in March 2023, any restorative material used in deciduous teeth was included and data about the title, number of citations, country/continent, authorship, journal, design of the study, type of restorative material, university and altmetrics score were analyzed. The papers, published between 1991 and 2002, ranged from 19 to 113 citations. The authors with the highest number of citations were Qvist V and Teglers PT. The experimental study was the main study design observed. Analyzing the continent and country with the highest number of citations, Europe highlighted and Brazil was predominant. The altmetric score was present in 23 papers, emphasizing two articles (43/6th and 73/7th). It was concluded that glass ionomer cement was the most studied material. A gap between the position of the papers correlating the bibliometrics and altmetrics analyzes was evident, demonstrating the need to disseminate the information beyond academic circles.

Influence of fluoride-releasing materials in the inhibition of enamel and dentin demineralization around restorations / Influência de materiais liberadores de flúor na inibição da desmineralização do esmalte e da dentina ao redor de restaurações

Objective: The aim was to evaluate the influence of fluoride-releasing restorative materials in enamel and dentin microhardness. Material and Methods: 40 blocks (5x5x3 mm) from cervical third of human molars received a cavity preparation between the enamel and dentin, and the restorations were subjected to in vitro caries model. Specimens were randomly restored with (n=10): conventional glass ionomer cement (Ketac Cem, 3M ESPE); polyacid-modified composite resin (Ionoseal, VOCO); resin-modified glass ionomer cement (Ionofast, Biodinâmica); or microhybrid composite resin (Filtek Z250, 3M ESPE). The specimens were sectioned longitudinally and enamel and dentin Knoop microhardness were determined at different distances from the restorative material (100, 200 and 300 µm) and depth of surface (20, 40 and 60 µm). The data were submitted to three-way repeated measures ANOVA and Tukey ́s test ( α =0.05). Results: For enamel, the double interactions between material x distance and material x depth were statistically significant. In all depths and distances, the highest values of enamel microhardness were observed for Ketac Cem. In dentin, the materials differed statistically from each other, and Ionoseal obtained higher microhardness values than those found in Ionofast. Conclusion: Conventional glass ionomer cement is more effective in preventing enamel demineralization around restoration followed by the polyacid-modified composite resin. In dentin, the polyacid-modified composite resin obtained better performance than resin-modified glass ionomer cement. (AU)

Objetivo: O objetivo foi avaliar a influência de materiais restauradores liberadores de flúor na microdureza do esmalte e da dentina. Material e Métodos: 40 blocos (5x5x3 mm) do terço cervical de molares humanos receberam preparo cavitário entre esmalte e dentina, e após a restauração foram submetidas a um modelo in vitro de cárie. As amostras foram restauradas aleatoriamente com (n=10): cimento de ionômero de vidro convencional (Ketac Cem, 3M ESPE); resina composta modificada por poliácidos (Ionoseal, VOCO); cimento de ionômero de vidro modificado por resina (Ionofast, Biodinâmica); ou resina composta microhíbrida (Filtek Z250, 3M ESPE). As amostras foram seccionadas longitudinalmente e a microdureza Knoop de esmalte e dentina foi determinada em diferentes distâncias do material restaurador (100, 200 e 300 µm) e profundidade de superfície (20, 40 e 60 µm). Os dados foram submetidos à ANOVA para medidas repetidas de três fatores e teste de Tukey (α =0,05). Resultados: Para o esmalte, as duplas interações entre material x distância e material x profundidade foram estatisticamente significativas. Em todas as profundidades e distâncias, os maiores valores de microdureza do esmalte foram observados para o Ketac Cem. Na dentina, Ionoseal obteve valores de microdureza superiores aos encontrados no Ionofast. Conclusão:O cimento de ionômero de vidro convencional é mais eficaz na prevenção da desmineralização do esmalte ao redor da restauração, seguido pela resina composta modificada por poliácidos. Na dentina, a resina composta modificada por poliácidos obteve melhor desempenho que o cimento de ionômero de vidro modificado por resina. (AU)

Evaluation of Residual Monomer Release After Polymerization of Colored Compomer Materials

ABSTRACT Objective: To evaluate the amount of residual monomers released after polymerization by the compomers in different colors and viscosities over time. Material and Methods: The compomer samples of different colors and viscosities (flowable compomers; blue-pink and packable compomers; A2-blue-pink-gold) were prepared in molds with an inner diameter of 5 mm and a height of 2 mm. In polymerization of samples, a LED unit was used. The amount of monomers released from the samples kept in 75% ethanol/water solution was measured by a high-performance liquid chromatography (HPLC) instrument in the 10th minute, in the 1st hour, and in the 1st, 7th, and 14th days. For statistical analyses, the paired sample t-test, independent sample t-test, and one-way ANOVA with Tukey's post hoc test were used. Results: The amount of residual monomers released from all materials increased over time. At the end of the 14th day, the most released monomer from all compomer samples was BisGMA. The total amounts of released monomers from the packable compomers were Gold>A2>blue>pink. The amount of residual monomers released from flowable compomers was higher in blue than in pink. Conclusion: The color and the viscosity are the factors affecting the residual monomer release in compomers.

Physicochemical and Tissue Response of PLA Nanofiber Scaffolds Sterilized by Different Techniques / Evaluación fisicoquímica y respuesta tisular de andamios nanofibrilares de PLA esterilizados por diferentes técnicas

ABSTRACT In recent years, tissue engineering has evolved considerably, due to the problems in the biomedical area concerning tissue regeneration therapies. Currently, work has been focused on the synthesis and physicochemical characterization of poly lactic acid scaffolds, a synthetic polyester that has been extensively study for its excellent biocompatibility and biodegradability. Moreover, sterilization strategies of scaffold are a crucial step for its application in tissue regeneration, however, the sterilization process have to maintain the structural and biochemical properties of the scaffold. Therefore, it is very important to carry out studies on the sterilization methods of the sample's material, since translational medicine is intended for in vivo applications. The aim of the present study was designed to analyze the effects of different sterilization techniques, i.e. ethylene oxide (ETO), gamma radiation (GR) and hydrogen peroxide- based plasma (H2O2) in biodegradable PLA scaffolds, and to determine the best sterilization technique to render a sterile product with minimal degradation and deformation, and good tissue response. Analysis of surface morphology showed that ETO and GR modified the PLA scaffolds without any change in its chemical composition. Moreover, the histological response showed that the scaffolds are biocompatible and those sterilized by GR showed a more severe inflammatory response, accompanied with the presence of giant foreign body cells. In conclusion, the results show that among sterilization techniques used in the preset study, the best results were observed with H2O2 sterilization, since it did not significantly modify the surface structure of the PLA fibers and their in vivo response did not cause an unfavorable tissue reaction.

RESUMEN En los últimos años, la ingeniería de tejidos ha evolucionado considerablemente, debido a las incógnitas en las terapias de regeneración en el área biomédica. Actualmente, se ha trabajado en la síntesis y caracterización fisicoquímica de andamios de poliácido láctico, el cual es un polímero sintético que se ha estudiado para aplicaciones en ingeniería de tejidos, debido a su biocompatibilidad y biodegradabilidad. El proceso de esterilización es un paso crucial en la aplicación de andamios en terapias de regeneración, sin embargo, la técnica de esterilización debe mantener las propiedades estructurales y bioquímicas del andamio. Por lo tanto, es muy importante realizar estudios sobre los métodos de esterilización de dichos andamios, ya que la medicina traslacional está diseñada para aplicaciones in vivo. El objetivo del presente estudio fue analizar los efectos de diferentes técnicas de esterilización como óxido de etileno (ETO), radiación gamma (GR) y plasma a base de peróxido de hidrógeno (H2O2) en andamios biodegradables de PLA, y determinar la mejor técnica de esterilización con mínima degradación y deformación, así como una respuesta tisular favorable. La estructura de la superficie de los andamios de PLA se modificó principalmente con las técnicas de óxido de etileno y radiación gamma, sin embargo, ninguna técnica modificó su composición química. Con la respuesta histológica se demostró que los andamios de PLA son biocompatibles y que los esterilizados por radiación gamma desencadenan una mayor respuesta inflamatoria y la formación de células gigantes de cuerpo extraño. En conclusión, los resultados muestran que las técnicas de esterilización utilizadas pueden modificar la morfología del andamio, sin embargo; los mejores resultados se observaron con la esterilización por plasma a base de peróxido de hidrógeno, ya que no modificó significativamente la estructura de la superficie de las fibras de PLA y su respuesta in vivo no provocó una reacción desfavorable en el tejido.

Restauraciones de lesiones cervicales no cariosas: un protocolo de revisión sistemática para la práctica clínica / Restorations of non-carious cervical lesions: a review protocol systematic for clinical practice

Las lesiones cervicales no cariosas son condiciones patológicas no bacterianas localizadas en el límite amelocementario de los dientes. Los principales biomateriales descritos para el tratamiento restaurador de estas lesiones son: vidrios ionómeros, vidrios ionómeros modificados con resinas, compómeros y resinas compuestas. El objetivo de este protocolo, consiste en establecer los elementos metodológicos de una revisión sistemática que evaluará el comportamiento clínico de restauraciones cervicales realizadas con estos biomateriales. Métodos: El protocolo fue diseñado, y será reportado, en línea con Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P 2015). Se realizará una búsqueda sensible en MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials y ClinicalTrials.gov, sin restricción por lenguaje o publicación, para identificar ensayos controlados aleatorizados que comparen dos o más tratamientos restauradores en lesiones cervicales no cariosas. Los desenlaces a evaluar serán la retención de las restauraciones y caries secundaria, según criterios RYGE/USPHS. Al menos dos investigadores realizarán de manera independiente la selección de los ensayos y la extracción de los datos. El riesgo de sesgo será evaluado utilizando la herramienta recomendada por la colaboración Cochrane. Si es posible, se realizará un metanálisis y los datos serán presentados en tablas de resúmenes de resultados mediante el método Grading of Recommendations Assesment, Development and Evaluation (GRADE). Fortalezas y debilidades: Esta revisión sistemática entregará evidencia actualizada sobre el comportamiento de cuatro biomateriales en el tratamiento de lesiones cervicales no cariosas. La principal limitación proviene de la baja cantidad o deficiencias metodológicas de los estudios primarios. Número de registro (PROSPERO): CRD42017071114.(AU)

Non-carious cervical lesions constitute a group of non-bacterial pathological conditions of the dental structure located at amelocementary junction. The main dental materials that have been described for the restorative treatment of these lesions are: ionomer glass, resin modified ionomer glass, compomers and composite resins. The objective of this protocol, is to establish the methodological elements of a systematic review, that will evaluate the clinical behavior of cervical restorations performed with four dental biomaterials. Methods: The protocol was designed, and will be reported, in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyzes Protocols (PRISMA-P 2015). We will conduct a sensitive search in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov, without language or publication restrictions, in order to identify randomized controlled trials comparing two or more restorative treatments in non-carious cervical lesions. The evaluated outcomes will be retention of restorations and secondary caries, according to RYGE/USPHS criteria. At least two reviewers will independently select studies and extract data. The risk of bias will be assessed using the tool recommended by the Cochrane Collaboration. If possible, a meta-analysis will be performed and the data will be presented in summary tables of results using the Grading of Recommendations Assesment, Development and Evaluation (GRADE) approach. Strength and Limitations: This systematic review will provide updated evidence on the behavior of four different dental biomaterials in the treatment of non-carious cervical lesions. The main limitation might arise from the low number or methodological limitations of primary studies. Register number (PROSPERO): CRD42017071114.(AU)

Marginal integrity of restorations produced with a model composite based on polyhedral oligomeric silsesquioxane (POSS)

Marginal integrity is one of the most crucial aspects involved in the clinical longevity of resin composite restorations.Objective To analyze the marginal integrity of restorations produced with a model composite based on polyhedral oligomeric silsesquioxane (POSS).Material and Methods A base composite (B) was produced with an organic matrix with UDMA/TEGDMA and 70 wt.% of barium borosilicate glass particles. To produce the model composite, 25 wt.% of UDMA were replaced by POSS (P25). The composites P90 and TPH3 (TP3) were used as positive and negative controls, respectively. Marginal integrity (%MI) was analyzed in bonded class I cavities. The volumetric polymerization shrinkage (%VS) and the polymerization shrinkage stress (Pss - MPa) were also evaluated.Results The values for %MI were as follows: P90 (100%) = TP3 (98.3%) = B (96.9%) > P25 (93.2%), (p<0.05). The %VS ranged from 1.4% (P90) to 4.9% (P25), while Pss ranged from 2.3 MPa (P90) to 3.9 MPa (B). For both properties, the composite P25 presented the worst results (4.9% and 3.6 MPa). Linear regression analysis showed a strong positive correlation between %VS and Pss (r=0.97), whereas the correlation between Pss and %MI was found to be moderate (r=0.76).Conclusions The addition of 25 wt.% of POSS in methacrylate organic matrix did not improve the marginal integrity of class I restorations. Filtek P90 showed lower polymerization shrinkage and shrinkage stress when compared to the experimental and commercial methacrylate composite.

[Microshear bond strength of transbond XT and assure universal bonding resin to stainless steel brackets, amalgam and porcelain]

Assure universal bonding resin is marketed with fluoride releasing potential. The manufacturer claims that it provides adequate bond strength between the bracket and amalgam and porcelain. This study compared the shear bond strength of Transbond XT and Assure universal bonding resin to stainless steel brackets, amalgam and porcelain in vitro. In this vitro study, 20 standard brackets of the maxillary central incisors, 20 feldspathic porcelain specimens and 20 self-cure acrylic cavities filled with amalgam were divided into 2 groups bonded with Transbond XT, and Assure. After surface preparation in each group, Transbond XT composite was applied to the surfaces using silicon tubes and light-cured for 20 seconds. Then, the microshear bond strength was determined using Zwick Roell machine. The data were subjected to two-way ANOVA, Tukey's post hoc test, Student's t-test and the Kruskal Wallis test. Different microshear bond strengths were obtained for the bond to stainless steel brackets, amalgam and porcelain by Transbond XT and Assure resin [p<0.000]. Using Assure for bonding to amalgam [7.2 +/- 1.46 vs. 10.12 +/- 4.97] and brackets [16.14 +/- 3.2 vs. 20.16 +/- 5.12; p<0.05] decreased microshear bond strength. However, Assure significantly increased the bond strength to porcelain compared to Transbond XT [28.84 +/- 6.42 vs. 22.48 +/- 3.6; p<0.01]. Non-parametric Kruskal-Wallis test showed significant differences in adhesive remnant index [ARI] between the two bonding agents only in the amalgam group [p=0.029]. Although the bond strength values of Assure were less than those of Transbond XT, Assure was able to create sufficient bond strength especially to porcelain

Fluoride release and recharge properties of six restorative materials / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the F(-) releasing and recharging properties of six dental restorative materials.</p><p><b>METHODS</b>Disc specimens 10 mm in diameter and 1 mm in thickness were prepared from 6 different dental restorative materials: Fuji VII [glass ionomer cement (GIC)], Fuji II LC (light-curing, GIC), Beautifil (giomer), Compoglass F (compomer), Charisma (composite) and Experimental I (a fluoride releasing composite), with 10 discs for each material. Specimens were dipped in 5 ml deionized water and F(-) release was detected using a fluoride-specific ion electrode every day from 1-7 days and every three days from 8-28 days. On day 28, specimens were exposed to a fluoride foam for 4 min and then dipped in water, then the F(-) concentration was detected every day for a week. The specimens were exposed to fluoride foam and fluoride release was detected repeatedly for three times.</p><p><b>RESULTS</b>All materials presented the highest F(-) release on the first day after dipping and the F(-) release sharply decreased after 24 h and slowly decreased after 3 days. On the first day, Fuji VII presented the highest F(-) release[(99.68±15.21) µg×cm(-2)×d(-1)], followed by Fuji II LC [(37.12±1.67) µg×cm(-2)×d(-1)], Experimental I [(22.93±1.53) µg×cm(-2)×d(-1)], Compoglass F[(15.28±0.70) µg×cm(-2)×d(-1)], Beautifil[(2.40±0.52) µg×cm(-2)×d(-1)] and Charisma[(0.11±0.02) µg×cm(-2)×d(-1)]. Within 28 days of dipping, both Fuji VII and Fuji II LC released more F(-) than other materials did(P < 0.05), followed by Compoglass F and Experimental I, and Beautifil and Charisma released the least F(-)(P < 0.01). After F(-) uptake, all materials released the highest F- on the first day and presented sharply decrease after 24 h and slowly decrease after 2 days. On the first day after F(-) uptake, Fuji VII presented the highest F(-) release (>40 µg×cm(-2) ×d(-1)), much more than other materials(P < 0.01), followed by Fuji II LC(>25 µg×cm(-2) ×d(-1)). Beautifil, Compoglass F and Experimental I were close in F(-) release value(15- 20 µg × cm(-2) × d(-1)), and Charisma showed the lowest F(-) release.</p><p><b>CONCLUSIONS</b>Two glass ionomers were shown to have highest capacity in F(-) release and uptake, followed by compomer and fluoride releasing composite. Composite demonstrated the lowest F(-) release and uptake and Giomer was comparable to composite in F(-) release and to compomer and fluoride releasing composite in F(-) uptake.</p>

The effect of different drinks on the color stability of different restorative materials after one month

OBJECTIVES: The aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials. MATERIALS AND METHODS: Three different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates (L*a*b*, DeltaL*, Deltaa*, Deltab*, and DeltaE*) were measured using a VITA Easyshade Compact (VITA Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (DeltaE) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test. RESULTS: The color difference (DeltaE*) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola (15.28 +/- 2.61) and black tea (12.22 +/- 2.73) showed the highest mean DeltaE* value after 30 day, followed by Filtek Ultimate Universal Restorative (5.99 +/- 1.25) and Filtek Ultimate Flowable (4.71 +/- 1.40) in black tea (p < 0.05). CONCLUSIONS: The compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.

Avaliação da liberação de flúor de compósitos ortodônticos: superBond Instant® e Color Change® / Assessment of release of fluoride composites orthodontic: superBond Instant® and Color Change®

Introdução: O objetivo deste estudo é testar a hipótese de que não há diferença no desempenho de compósitos ortodônticos entre si quanto à liberação de flúor. Métodos: Os materiais foram divididos em 3 grupos: 2 compósitos ortodônticos utilizados para colagem de bráquetes ortodônticos: Grupo SI (SuperBond Instant, OrthoSource) e Grupo CC (Color Change, OrthoSource) e 1 cimento de ionômero de vidro (CIV) convencional utilizado para cimentação de bandas ortodônticas; Grupo S (Sumo, OrthoSource), como controle. A liberação de flúor foi medida durante 28 dias (1h, 24h, 1, 3, 7, 14, 21 e 28 dias), através de eletrodo íon seletivo conectado a um analisador de íons. Os dados foram submetidos aos testes não paramétricos de Kruskal-Wallis e de Mann-Whitney, a um nível de significância de 5%. Resultados: Os resultados evidenciaram que os materiais atingiram o pico máximo de liberação de flúor com 24h após presa inicial. Houve diferença estatística entre os grupos SI e CC com o grupo S em todos os tempos avaliados (p < 0.05). Houve diferença estatística entre os grupos SI e CC nos tempos de 1h, 24h, 3, 7, 14 e 21 dias (p < 0.05). Conclusão: A hipótese foi rejeitada. O compósito Color Change apresentou desempenho melhor comparado ao SuperBond Instant, porém ambos apresentaram uma liberação de flúor pouco expressiva comparados ao CIV convencional.

Introduction: The objective of this study is to test the hypothesis that there is no difference in performance of orthodonticcomposites in terms of their fluoride release. Methods: The materials were divided into three groups:two composites used for orthodontic Bonding of orthodontic brackets: Group SI (Instant SuperBond, Ortho-Source) and Group CC (Color Change, OrthoSource) and a glass ionomer cement (GIC) used for conventionalcementing orthodontic bands: Group S (Sumo, OrthoSource) as the control. Fluoride release was measuredduring 28 Days (1h, 24h, 1, 3, 7, 14, 21 and 28 Days), by ion selective electrode connected to an ion analyzer.The data were subjected to nonparametric tests of Kruskal-Wallis and Mann-Whitney, with a significance levelof 5%. Results: The results showed that the materials reached the peak of fluoride release after 24 hours afterinitial set. Statistical difference between groups SI and DC with the group S at all times evaluated (p <0.05).Statistical difference between groups SI and CC in 1h, 24h, 3, 7, 14 and 21 Days (p <0.05). Conclusion: Thehypothesis was rejected. Color Change composite performance was better compared to SuperBond Instant, butboth had a very expressive fluoride release compared to conventional GIC.

Comparison of conventional glass ionomer cement and compomer in class II restorations in primary molars: six months study

Restorations in primary teeth continue to be an important facet of restorative dentistry. Traditionally, posterior primary teeth have been restored with amalgam. Recently, there has been a range of tooth-colored materials available for restoring primary and young mixed dentitions. These materials are conventional glass ionomer cements and composite resins, resin-modified glass ionomer cements and compomers. To compare the clinical performance of conventional glass ionomer cement with compomer, in class II restorations in primary molars. This was a quasi experimental study conducted at Operative Department of Fatima Jinnah Dental College Hospital, Karachi during period of six months, on 132 patients meeting the inclusion criteria [2 proximally carious primary molars, 264 carious lesions] were included in the study. All 132 patients enrolled in the study were recalled after six months and restorations were clinically examined for marginal adaptation and anatomic form. Out of 264 restorations, 10 teeth were lost because of the normal exfoliation of primary teeth.124 restorations failed during the follow-up period from which 123 [93.2%] were conventional glass ionomer cement and only 1[0.8%] was compomer. In terms of marginal adaptation and anatomic form, compomer performed significantly better than Conventional glass ionomer cement in class II cavity in primary molars

Bond Strength of composite repairs using flowable, conventional resins or the association of both / Resistência de união de reparos de resinas compostas usando resinas convencionais, fluidas, ou a associação de ambas

Objectives: The aim of this in vitro study was to evaluate the effect on bond strength of composite repairs using flowable resin as an intermediate agent . Methods: Thirty truncated cones were fabricated with Grandio SO (VOCO) and were thermo-cycled for 5000 cycles for artificial aging. Specimen’s surface was sandblasted with aluminum oxide, cleaned with air/water spray and conditioned with phosphoric acid for 15 s. One coat of Admira Bond Adhesive (VOCO) was applied and light cured for 20 s. Specimens were divided into 3 groups according to the repairing material used (n = 10): Conventional Resin – Grandio SO (R), A thin layer of Flowable resin – Grandio SO Heavy Flow + conventional Resin (FR), and Flowable resin (F). Over the original specimens, a sectional cone-shaped teflon matrix was hold in position and the cones were built according the groups described above. Other thirty specimens were built, 10 of each group, simulating a restoration without repair. Specimens were submitted to tensile stress in a universal testing machine. Data were recorded in MPa and evaluated with ANOVA, Tukey´ s and non-paired “t’’ tests. Results: ANOVA showed significant differences among groups in which repair was performed (p < 0.00). The results of Tukey´ s test for those groups were: R (19.89 + 5.31)ab; F+R (14.49 + 5.59)a; F (20.91 + 3.99)b. The groups followed by the same letter did not show statistical differences. Non-paired “t” test showed that groups R and F repairs were similar to the correspondent groups simulating restoration without repair. Conclusions: The repair with conventional or flowable composite produced bond strength values similar to cohesive strength of the same materials. The use of a thin layer of flowable resin as an intermediate agent in composite repair decreased the bond strength when compared the same method for restoration.

Objetivos: O objetivo deste estudo in vitro foi avaliar o efeito sobre a resistência de união de reparos de compósitos com resina fluida como um agente intermediário. Métodos: Trinta cones truncados foram fabricados com Grandio SO (VOCO) e foram termociclados por 5.000 ciclos de envelhecimento artificial. A superfície da amostra foi jateada com óxido de alumínio, limpa com spray ar / água e condicionada com ácido fosfórico por 15 s. Uma camada de adesivo (Admira - VOCO) foi aplicada e fotopolimerizada por 20 s. As amostras foram divididas em três grupos de acordo com o material de reparo utilizado (n=10): resina convencional - Grandio SO (R), uma fina camada de resina flowable - Grandio SO Heavy Flow + Resina convencional (FR), e resina flowable (F). Sobre espécimes originais, foi adaptada uma matriz, e os cones foram construídos de acordo com os grupos descritos acima. Trinta amostras foram construídos, 10 de cada grupo, simulando uma restauração sem reparos. As amostras foram submetidas ao Teste de tração em uma máquina universal de ensaios. Os dados foram registrados em MPa e avaliados com ANOVA, Tukey e teste “t’’ não pareado. Resultados: ANOVA mostrou diferenças significativas entre os grupos em que o reparo foi realizado (p < 0,00). Os resultados do teste de Tukey para os grupos foram: R (19,89 + 5,31) ab; F + R (14,49 + 5,59) a; F (20,91 + 3,99) b. Os grupos seguidos pela mesma letra não apresentaram diferenças estatísticas. O Teste “t” não pareado de Student mostrou que as reparações dos grupos R e F foram semelhantes aos dos grupos correspondentes que simulam restauração sem reparos. Conclusões: O reparo com resina flowable ou convencional produziu níveis de resistência próximos a força coesiva dos mesmos materiais. A utilização de uma camada fina de resina fluida como um agente intermediário no reparo dos compósitos diminuiu a resistência de união, quando comparado o mesmo método para a restauração.

Effects of bleaching agents on the microleakage of class V cavities restored with glass-ionomer cements / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the effects of a bleaching gel and a whitening strip on the microleakage of three different glass-ionomer cements.</p><p><b>METHODS</b>Forty-five freshly extracted human premolars were used and class V cavity was prepared on the buccal and lingual surfaces. The teeth were randomly assigned to A, B and C groups and restored as follows: Conventional strengthen glass-ionomer cement (Ketac Molar Easymix), compomer (F2000) and compomer (Dyract AP). Teeth were kept in distilled water at 37 degrees C for 7 days. Then the specimens were thermocycled for 500 times. Each group was randomly divided into 3 subgroups which were treated for 21 days with one of the following: Whitening strip (14% hydrogen peroxide), bleaching gel (10% carbamide peroxide), or distilled water (control). After bleaching, the teeth were placed in a solution of basic fuchsin dye for 24 hours, then the teeth were sectioned longitudinally to evaluate the dye penetration. The depth of staining along the tooth restoration interface was recorded with a stereomicroscope.</p><p><b>RESULTS</b>There were no signicant differences between the two bleaching agents in microleakage of restorations (P>0.05). The two bleaching agents did not significantly affect the microleakage of compomer (P>0.05), whereas the microleakage of glass-ionomer cement in the experimental groups was higher than that in the control group (P<0.05).</p><p><b>CONCLUSION</b>There are no significant differences in microleakage of restorations between bleaching gel (10% carbamide peroxide) and whitening strip (14% hydrogen peroxide). The two bleaching agents do not significantly affect the microleakage of compomer but adversely affect the microleakage of strengthen glass-ionomer cement.</p>

Surface roughness of orthodontic band cements with different compositions

OBJECTIVES: The present study evaluated comparatively the surface roughness of four orthodontic band cements after storage in various solutions. MATERIAL AND METHODS: Eight standardized cylinders were made from 4 materials: zinc phosphate cement (ZP), compomer (C), resin-modified glass ionomer cement (RMGIC) and resin cement (RC). Specimens were stored for 24 h in deionized water and immersed in saline (pH 7.0) or 0.1 M lactic acid solution (pH 4.0) for 15 days. Surface roughness readings were taken with a profilometer (Surfcorder SE1200) before and after the storage period. Data were analyzed by two-way ANOVA and Tukey's test (comparison among cements and storage solutions) or paired t-test (comparison before and after the storage period) at 5 percent significance level. RESULTS: The values for average surface roughness were statistically different (p<0.001) among cements at both baseline and after storage. The roughness values of cements in a decreasing order were ZP>RMGIC>C>R (p<0.001). After 15 days, immersion in lactic acid solution resulted in the highest surface roughness for all cements (p<0.05), except for the RC group (p>0.05). Compared to the current threshold (0.2 µm) related to biofilm accumulation, both RC and C remained below the threshold, even after acidic challenge by immersion in lactic acid solution. CONCLUSIONS: Storage time and immersion in lactic acid solution increased the surface roughness of the majority of the tested cements. RC presented the smoothest surface and it was not influenced by storage conditions.

in vitro evaluation of marginal leakage using invasive and noninvasive technique of light cure glass ionomer and flowable polyacid modified composite resin used as pit and fissure sealant.

Aim: This study compared the microleakage of light cure glass ionomer and flowable compomer as pit and fissure sealant, with and without tooth preparation. Materials and Methods: One hundred premolars that were extracted for orthodontic purpose were used. After adequate storage and surface debridement, the teeth were randomly divided into four groups. In Group I and III, the occlusal surfaces were left intact, while in Group II and Group IV, tooth surfaces were prepared. Teeth in Group I and Group II were sealed with Light cure glass ionomer, whereas flowable compomer was used to seal teeth in Group III and IV. The sealed teeth were then immersed in dye. Subsequently, buccolingual sections were made and each section was examined under stereomicroscope for microleakage followed by scoring. Results: In group I, microleakage score ranged from 2 to 4 with mean of 3.64 (±0.757), while in group II the range was observed to be 1-4 with mean of 2.88 (±1.236). Group III recorded a range of 0-4 with the mean of 2.20 (±1.443) while 0-2 and 0.60 (±0.707) being the range and mean observed, respectively, for group IV. Conclusion: Flowable compomer placed after tooth preparation showed better penetration and less marginal leakage than the light cure glass ionomer.

Avaliação clínica de restaurações reparadas por resina composta à base de silorano: estudo longitudinal randomizado controlado / Repair of dimethacrylate-based composite restorations using a silorane-based composite: a prospective, randomized clinical trial

Objetivo: Este estudo investigou o desempenho clínico de restuarações Classe I e II de resina composta à base de dimetacrilato reparadas por uma resina composta de baixa contração à base de silorano ou por uma resina composta à base de dimetacrilato, em baseline e ao longo de 6 a 12 meses. Materiais e métodos: cem restaurações defeituosas de resina composta à base de dimetacrilato foram reparadas neste estudo. Destas, 93 foram examinadas uma semana após terem sido reparadas - baseline, 91 após 6 meses e 83 após 12 meses. As restaurações foram alocadas aleatoriamente em dois grupos de tratamento - Controle (n=50): Adper SE/ESPF + Filtek P90 3M/ESPE...

Degree of conversion and surface hardness of two nanocomposites compared to three other tooth-colored restorative materials

The aim of the laboratory study was to evaluate the degree of conversion [DC] and surface hardness of two nanofilled resin composite restorative materials compared to three other tooth-colored restorative materials. A light-emitting diode curing unit was used to photo-activate a hybrid composite [Filtek[TM] Z250], two nanofilled composites [Tetric[restricted] EvoCeram, Filtek[TM] Supreme XT], a nano-ionomer [Ketac[TM] N100] and a compomer [Dyract[restrected] eXtra]. After 24 hours dry storage in the dark at 37°C, the DC was determined using Fourier transformation infrared spectroscopy [FTIR]. A microhardness tester was used to measure the Vickers Hardness Number [VHN]. Data for DC and VHN were analyzed using one-way analysis of variance with Tukey's multiple comparison test, and by using Pearson's correlation test [P=0.05 for statistical significance]. The highest mean value for DC was obtained with Tetric EvoCeram [79.4 +/- 6.7%]. Filtek Z250 showed a significantly lower mean DC [58.3 +/- 1.8%] than any of the other tested materials [P<0.001]. Filtek Supreme XT, Ketac N100, Dyract eXtra and Tetric EvoCeram showed no significant DC differences among them [P>0.05]. Filtek Z250 had the highest VHN [97.6 +/- 2.8 MPa], while the lowest value was recorded with Tetric EvoCeram [55.3 +/- 2.9 MPa]. The VHN was significantly different among all tested materials [P<0.001]. A significant and highly negative correlation existed between the DC and surface hardness [r=0.736, P<0.01]. The study concluded that Nanofilled composites may have a higher DC and a reduced VHN compared to hybrid composites, with clinical implications. Correlation between these two properties for various nanofilled materials requires further investigation

[Evaluating the microleakage of class V cavity preparations restored with resin composite and resin modified glass ionomer]

Marginal seal in class V Cavities and determining the best restorative material to decrease microleakage of them is very important in operative dentistry. To evaluate the microleakage of class V cavity preparations restored with three different types of resin composite and resin modified glass Ionomer. Two class V cavities were prepared in buccal surface of 32 recently extracted premolar teeth. The occlusal margin of each restoration was on enamel and the gingival margin on dentin. Teeth were randomly assigned to four groups of 8 teeth and restored as follows: Group I: microhybrid resin composite [Z250]; Group II: nano composite [supreme]; Group III: Flowable composite [3M]; Group IV: resin modified glass Ionomer [vitremer]. In all groups the manufacture instructions were strictly followed. All teeth were immersed in 50% Silver Nitrate during 4 hours and developing solution for 8 hours after thermocycling. The teeth were longitudinally sectioned and observed under a stereomicroscope. The degree of dye penetration was recorded and analyzed with the Kruskal-Wallis and Mann-Whitney test. There was no evidence of microleakage on the enamel margins in any groups. When the margins were in dentin vitremer and flowable composite had the less and the most level of microleakage in dentinal margin respectively [P<0.05]. There was no significant differents in other groups of dentinal margin. Vitremer has an efficterness role and flawable composite has a weakness role in reducting microleakage of dentinal margin

Degradação dos materiais restauradores utilizados em lesões cervicais não cariosas / Degradation of the restorative materials used in non-carious cervical lesions

OBJETIVO: Avaliar o efeito de bebidas ácidas e da escovação em materiais utilizados em lesões cervicais não cariosas. MÉTODOS: Três resinas compostas, um compômero e um cimento de ionômero resino-modificado foram testados. Para cada material, cinco espécimes foram imersos em uma das soluções teste (suco de laranja, coca-cola, uísque ou água destilada) por 10 dias a 37ºC. Em seguida, os espécimes foram submetidos à escovação (20000 ciclos, 200g de carga). O peso e a rugosidade superficial foram avaliados antes e após a imersão nas soluções e escovação. Os dados foram analisados pela ANOVA/Teste Tukey (p<0,05). RESULTADOS: As imersões em suco de laranja e coca-cola seguida de escovação causaram significativamente maior perda de peso para o compômero e cimento de ionômero de vidro resino-modificado comparado às resinas compostas. O maior aumento de rugosidade superficial foi observado no cimento de ionômero de vidro resino-modificado após imersão em suco de laranja seguida de escovação. CONCLUSÃO: A imersão em bebidas ácidas seguida de escovação causou degradação nos materiais restauradores avaliados, com perda de material e aumento na rugosidade superficial.

OBJECTIVE: Evaluate the effect of acidic beverages and brushing on the restorative materials used in non-carious cervical lesions. METHODS: Three composite resins, one compomer and one resin-modified glass ionomer were tested. Five specimens of each material were immersed in each of the test solutions (orange juice, Coca-Cola, whisky and distilled water) for a 10-day period at 37ºC. Next, the specimens were brushed (20000 cycles with a load of 200g). Weight and surface roughness were measured before and after immersion and brushing. The data were analyzed by ANOVA/Tukey Test (p<0.05). RESULTS: The compomer and resin-modified glass ionomer lost significantly more weight after immersion in orange juice and Coca-Cola followed by brushing than the composite resins. The resin-modified glass-ionomer presented the highest increase in surface roughness after orange juice immersion and brushing. CONCLUSION: Immersion in acidic beverages followed by brushing degraded the restorative materials tested, causing loss of material and increased surface roughness.

Effect of different topical fluoride applications on the surface roughness of a colored compomer

OBJECTIVE: The aim of this study was to evaluate the effect of neutral sodium fluoride (NNaF) gel and acidulated phosphate fluoride (APF) gel on the surface roughness of colored compomer (Twinky Star), conventional compomer (Compoglass F) and resin-modified glass-ionomer cement (RMGIC) (Photac-Fil). MATERIAL AND METHODS: A total of 45 standardized disc-shaped specimens were prepared for each material. After 24 h, finishing and polishing of specimens were done with aluminum oxide disc. Surface treatments with topical fluoride agents or distilled water (control) were performed four times, and interspersed with 8 pH cycles, simulating high cariogenic challenges. After the treatment, the surface roughness (Ra) was determined using a profilometer. In each group, specimens with Ra closest to the mean were examined with a scanning electron microscope (SEM) at ×1,000 and ×3,500 magnifications. Two-way ANOVA was used to evaluate Ra measurements, and the differences in Ra values between subgroups for each material and each topical applications were compared by Tukey's highly significant difference pairwise comparisons. RESULTS: No statistically significant difference in Ra between the Twinky Star and Compoglass F was found. However, Photac Fil showed significantly higher Ra than these materials after all surface treatments. There was a general trend of Ra increase from controls to NNaF and APF gels for all materials. SEM observations revealed that the surface micromorphology of Twinky-Star did not differ significantly from that of Compoglass F. CONCLUSION: Both the compomers and the RMGIC showed significantly higher surface roughness when subjected to APF gel application.