Clinical evaluation of multiple-surface ART restorations: three-year follow-up / Avaliação clínica de restaurações de ART de superfícies múltiplas: acompanhamento de três anos

Objective: To evaluate the performance of multiple-surface restorations made with two different glass-ionomer cements (GICs) in permanent teeth using the Atraumatic Restorative Treatment (ART). Material and methods: A total of 60 restorations were placed in schoolchildren (9-16 years of age) by two dentists using standard ART procedures. The restorations were randomly divided into two groups. Thirty cavities were filled with high-viscosity GIC (Ketac Molar-3M ESPE) and 30 cavities were filled with resin-modified GIC (Fuji VIII-GC Corp.). Two calibrated independent examiners carried out the evaluation according to ART criteria. Data were statistically analyzed using multiple logistic regression models to evaluate the variables associated with the success (GIC, operator, Class type). The 95% Confidence Intervals (CI) for success were based on the binomial distribution. A difference was statistically significant if p < 0.05. Results: In a 3-year follow-up, 57 restorations were evaluated. In the Ketac Molar group, 3 restorations were not evaluated, 21 were considered successful and 6 unsuccessful. In the Fuji VIII group, 28 restorations were considered successful and 2 unsuccessful. The logistic regression model showed that the combination of the variables was only statistically significant in relation to survival of ART restorations (p = 0.036). There were no statistically significant differences between the groups taking each variable into account. The best performance included the combination: Fuji VIII, operator B and Class I involving two or more tooth surfaces. Conclusion: The clinical performance of the multiplesurface ART restorations of both materials was considered satisfactory with a high success rate after 3 years.

Objetivo: Avaliar o comportamento clínico de restaurações de superfícies múltiplas, realizadas com dois cimentos de ionômero de vidro (CIVs) em dentes permanentes, utilizando-se o Tratamento Restaurador Atraumático (ART). Material e Métodos: 60 restaurações foram realizadas em escolares (idade entre 9 - 16 anos) por dois dentistas utilizando-se os procedimentos convencionais do AR. As restaurações foram distribuídas aleatoriamente em dois grupos. Trinta cavidades foram restauradas com CIV de alta viscosidade (Ketac Molar - 3M ESPE) e 30, com CIV modificado por resina (Fuji VIII-GC Corp.). Dois avaliadores calibrados e independentes realizaram a avaliação segundo os critérios do ART. Os resultados foram submetidos à análise estatística utilizando-se modelos de regressão logística múltipla, avaliando-se o sucesso em função das variáveis associadas (CIV, operador e tipo de cavidade). Intervalos de confiança de 95% para o sucesso foram baseados na distribuição binomial. Diferenças estatisticamente significantes ocorreram se p < 0,05. Resultados: Em 3 anos de acompanhamento 57 restaurações foram avaliadas. No grupo do Ketac Molar, 3 restaurações não foram avaliadas, 21 obtiveram sucesso e 6 falharam. No grupo do Fuji VIII, 28 restaurações obtiveram sucesso e 2 falharam. A combinação de variáveis foi somente significante em relação à sobrevida das restaurações (p = 0,036). Não houve diferenças entre os grupos considerando-se cada variável independentemente. A combinação apresentando melhor desempenho foi: Fuji VIII, operador B e Classe I envolvendo duas ou mais superfícies dentárias. Conclusão: O desempenho clínico de restaurações de ART de superfícies múltiplas foi considerado satisfatório para ambos os materiais testados, apresentando altos índices de sucesso após três anos.

In vitro interactions between lactic acid solution and art glass-ionomer cements.

OBJECTIVES: Production of acids such as lactic acid contributes to establish a cariogenic environment that leads to dental substrate demineralization. Fluoride plays an important role in this case and, as fluoride-releasing materials, glass-ionomer cements are expected to contribute to minimize deleterious reactions. This study evaluated interactions of glass-ionomer cements used in atraumatic restorative treatment (ART-GICs) with an aqueous lactic acid solution, testing the null hypotheses that no changes occur in the pH of the solution or on the surface roughness and mass of the ART-GICs when exposed to lactic acid solution over a 6-week period. MATERIAL AND METHODS: Ketac Molar, Fuji IX, Vitro Molar and Magic Glass were tested, and compared to Filtek Z250 and Ketac Fil Plus as control groups. Six specimens of each material were made according to manufacturers' instructions. The pH of the solution and roughness and mass changes of each specimen were determined over 6 weeks. Each specimen was individually stored in 2 mL of 0.02 M lactic acid solution for 1 week, renewing the solution every week. pH of solution and mass of the specimens were monitored weekly, and surface roughness of the specimens was assessed before and at the end of the 6-week acid challenge. pH and mass data were analyzed statistically by repeated measures using one-way ANOVA and Tukey's post-hoc tests for each material. Paired t-tests were used for roughness analysis. Tukey's post-hoc tests were applied to verify differences of final roughness among the materials. Significance level was set at 5%. RESULTS: The null hypotheses were partially rejected. All materials were able to increase the pH of the lactic acid solution and presented rougher surfaces after immersion, while mass change was minimal and generally not statistically significant. CONCLUSIONS: These findings can be helpful to predict the performance of these materials under clinical conditions. A protective action against the carious process with significant surface damage due to erosion may be expected.

In vitro interactions between lactic acid solution and art glass-ionomer cements

OBJECTIVES: Production of acids such as lactic acid contributes to establish a cariogenic environment that leads to dental substrate demineralization. Fluoride plays an important role in this case and, as fluoride-releasing materials, glass-ionomer cements are expected to contribute to minimize deleterious reactions. This study evaluated interactions of glass-ionomer cements used in atraumatic restorative treatment (ART-GICs) with an aqueous lactic acid solution, testing the null hypotheses that no changes occur in the pH of the solution or on the surface roughness and mass of the ART-GICs when exposed to lactic acid solution over a 6-week period. MATERIAL AND METHODS: Ketac Molar, Fuji IX, Vitro Molar and Magic Glass were tested, and compared to Filtek Z250 and Ketac Fil Plus as control groups. Six specimens of each material were made according to manufacturers' instructions. The pH of the solution and roughness and mass changes of each specimen were determined over 6 weeks. Each specimen was individually stored in 2 mL of 0.02 M lactic acid solution for 1 week, renewing the solution every week. pH of solution and mass of the specimens were monitored weekly, and surface roughness of the specimens was assessed before and at the end of the 6-week acid challenge. pH and mass data were analyzed statistically by repeated measures using one-way ANOVA and Tukey's post-hoc tests for each material. Paired t-tests were used for roughness analysis. Tukey's post-hoc tests were applied to verify differences of final roughness among the materials. Significance level was set at 5 percent. RESULTS: The null hypotheses were partially rejected. All materials were able to increase the pH of the lactic acid solution and presented rougher surfaces after immersion, while mass change was minimal and generally not statistically significant. CONCLUSIONS: These findings can be helpful to predict the performance of these materials under clinical conditions. A ...

Effect of light curing unit on resin-modified glass-ionomer cements: a microhardness assessment

OBJECTIVE: To evaluate the microhardness of resin-modified glass-ionomer cements (RMGICs) photoactivated with a blue light-emitting diode (LED) curing light. MATERIAL AND METHODS: Thirty specimens were distributed in 3 groups: Fuji II LC Improved/GC (RM1), Vitremer/3M ESPE (RM2) and Filtek Z250/ 3M ESPE (RM3). Two commercial light-curing units were used to polymerize the materials: LED/Ultrablue IS and a halogen light/XL3000 (QTH). After 24 h, Knoop microhardness test was performed. Data were submitted to three-way ANOVA and Tukey's test at a pre-set alpha of 0.05. RESULTS: At the top surface, no statistically significant difference (p>0.05) in the microhardness was seen when the LED and QTH lights were used for all materials. At the bottom surface, microhardness mean value of RM2 was significantly higher when the QTH light was used (p<0.05). For RM1, statistically significant higher values (p<0.05) were seen when the LED light was used. No statistically significant difference (p>0.05) was seen at the bottom surface for RM3, irrespective of the light used. Top-to-bottom surface comparison showed no statistically significant difference (p>0.05) for both RMGICs, regardless of the light used. For RM3, microhardness mean value at the top was significantly higher (p<0.05) than bottom microhardness when both curing units were used. CONCLUSION: The microhardness values seen when a LED light was used varied depending on the restorative material tested.

Effect of light curing unit on resin-modified glass-ionomer cements: a microhardness assessment.

OBJECTIVE: To evaluate the microhardness of resin-modified glass-ionomer cements (RMGICs) photoactivated with a blue light-emitting diode (LED) curing light. MATERIAL AND METHODS: Thirty specimens were distributed in 3 groups: Fuji II LC Improved/GC (RM1), Vitremer/3M ESPE (RM2) and Filtek Z250/3M ESPE (RM3). Two commercial light-curing units were used to polymerize the materials: LED/Ultrablue IS and a halogen light/XL3000 (QTH). After 24 h, Knoop microhardness test was performed. Data were submitted to three-way ANOVA and Tukey's test at a pre-set alpha of 0.05. RESULTS: At the top surface, no statistically significant difference (p>0.05) in the microhardness was seen when the LED and QTH lights were used for all materials. At the bottom surface, microhardness mean value of RM2 was significantly higher when the QTH light was used (p<0.05). For RM1, statistically significant higher values (p<0.05) were seen when the LED light was used. No statistically significant difference (p>0.05) was seen at the bottom surface for RM3, irrespective of the light used. Top-to-bottom surface comparison showed no statistically significant difference (p>0.05) for both RMGICs, regardless of the light used. For RM3, microhardness mean value at the top was significantly higher (p<0.05) than bottom microhardness when both curing units were used. CONCLUSION: The microhardness values seen when a LED light was used varied depending on the restorative material tested.

Water sorption and solubility of dentin bonding agents light-cured with different light sources.

OBJECTIVE: The aim of this study was to compare water sorption (WS) and solubility (WSB) of different dentin bonding agents (DBA) as regards classification and light-activation system. The null hypotheses were: (1) there is no difference among DBA with respect to water sorption and solubility; (2) there is no effect of light-curing source on water sorption and solubility of DBA. METHODS: The tested materials were: three-step etch-and-rinse (ScotchBond multi-purpose and Heliobond-control groups), two-step etch-and-rinse (Excite, Adper Single Bond, Adper Single Bond 2), self-etching (Adhse) and all-in-one (Xeno III) systems. For each material, six specimens were prepared (0.8mmx5.5mm) for each light-activation device: halogen lamp (control) or light-emitting diodes (LED). They were transferred to desiccators until a constant mass was obtained (m(1)), subsequently immersed in deionized water until no alteration was obtained (m(2)). Following, the specimens were reconditioned to constant mass in desiccators (m(3)). The volume (V) of each specimen was calculated (mm(3)). WS and WSB were determined using the equations (m(2)-m(3)/V) and (m(3)-m(1)/V), respectively. Data were subjected to one-way analysis of variance and Tukey test (p<0.05). The influence of photo-activation units was analyzed by t-test. RESULTS: Higher values of WS and WSB were observed for the two-step etch-and-rinse and all-in-one systems. The employed light-activation unit also affected the tested characteristics. Thus, the anticipated null hypotheses were rejected. CONCLUSIONS: Simplified systems were more susceptible to water adverse and they may become more prone to degradation over time regardless of the type of light-activation source.

Water sorption of resin-modified glass-ionomer cements photoactivated with LED

The Light Emitting Diodes (LED) technology has been used to photoactivate composite resins and there is a great number of published studies in this area. However, there are no studies regarding resin-modified glass-ionomer cements (RMGIC), which also need photoactivation. Therefore, the aim of this study was to evaluate water sorption of two RMGIC photoactivated with LED and to compare this property to that obtained with a halogen light curing unit. A resin composite was used as control. Five specimens of 15.0 mm in diameter x 1.0 mm in height were prepared for each combination of material (Fuji II LC Improved, Vitremer, and Filtek Z250) and curing unit (Radii and Optilight Plus) and transferred to desiccators until a constant mass was obtained. Then the specimens were immersed into deionized water for 7 days, weighed and reconditioned to a constant mass in desiccators. Water sorption was calculated based on weight and volume of specimens. The data were analyzed by two-way ANOVA and Tukey test (p < 0.05). Specimens photocured with LED presented significantly more water sorption than those photocured with halogen light. The RMGIC absorbed statistically significant more water than the resin composite. The type of light curing unit affected water sorption characteristics of the RMGIC.

A tecnologia baseada em Diodos emissores de luz (LED) tem sido utilizada para a fotoativação de resinas compostas e existe um grande número de estudos publicados a este respeito. Entretanto, não existem estudos envolvendo cimentos de ionômero de vidro modificados por resina (CIVMR), que também necessitam fotoativação. Assim, o objetivo deste estudo foi o de avaliar a sorção de água de dois CIVMR fotoativados com LED e comparar essa propriedade com aquela obtida com unidade com lâmpada halógena. Uma resina composta foi utilizada como controle. Cinco espécimes com 15,0 mm diâmetro x 1,0 mm de altura foram preparados para cada combinação de material (Fuji II LC Improved, Vitremer e Filtek Z250) e fonte de luz (Radii e Optilight Plus) e transferidos a dessecadores até a obtenção de massa constante. Em seguida, os espécimes foram imersos em água deionizada por 7 dias, pesados e recondicionados a uma massa constante em dessecadores. A sorção de água foi calculada com base no peso e no volume dos espécimes. Os dados foram analisados por ANOVA a dois critérios e teste de Tukey (p < 0,05). Os espécimes fotoativados com LED apresentaram maior sorção de água que os fotoativados com lâmpada halógena. Os CIVMR absorveram mais água que a resina composta. O tipo de unidade de fotoativação afetou as características de sorção de água dos CIVMR.

Influência do tipo de unidade fotoativadora (LED ou QTH) na microinfiltração de restaurações com resinas compostas / Influence of type of cure units (LED or QTH) on microleakage of composite resin restorations

Objetivo: Esse estudo testa a hipótese de que não há influência do tipo de unidade fotoativadora (LED ou QTH) na microinfiltração de restaurações classe II de diferentes resinas compostas, realizadas em dentes bovinos. Materiais e Métodos: 20 incisivos bovinos foram selecionados e cavidades classe II foram confeccionadas nas faces proximais de cada dente, totalizando 40 preparos. Os espécimes foram divididos em dois grupos de 10 dentes cada (grupos L e H). No grupo L, as 10 cavidades mesiais foram restauradas com o sistema Single Bond / Z100 (3M) e as 10 cavidades distais foram restauradas com Single Bond / Definite (Degussa) e foram fotopolimerizadas com o LED (Ultraled - Dabi-Atlante). No grupo H os procedimentos restauradores foram similares aos do grupo L, porém os espécimes foram fotopolimerizados com a fonte de luz convencional (Curing light 2500 - 3M). Os dentes foram, então, armazenados em água (37°C) e submetidos à termoreciclagem (5-55°C, 1 min, 500 ciclos). Posteriormente, foram imersos em fucsina básica por 3h, lavados pelo mesmo tempo e seccionados no sentido mesiodistal. A seção com maior extensão de infiltração correspondente a cada resina (mesial e distal) foi selecioanda por meio de lentes de 10X de aumento, avaliadas por três examinadores e a infiltração determinada por escores de 0 a 3. Resultados: Os preparos restaurados com o sistema SB/Definite mostraram maior grau de infiltração comparado ao SB/Z100 e não houve influência da fonte de luz empregada. Conclusão: As cavidades restauradas com ambos os sistemas não foram afetados pela fonte de luz. As restaurações SB/Z100 mostraram menor infiltração em relação ao SB/Definite

Reanatomização de dentes anteriores altamente comprometidos em cor, forma e posição / Reshaping of anterior teeth compromised in color, shape and position

Facetas diretas em resina composta têm se tornado um recurso bastante popular na busca por um sorriso harmonioso. Os avanços recentes marcados pelas técnicas adesivas, evolução na qualidade das resinas compostas e o desenvolvimento de pinos intra-radiculares de fibra de vidro possibilitam alcançar um resultado estético excelente, com conservação maior da estrutura dental em relação a outras técnicas. Este trabalho aborda um caso clínico dos dentes 11, 12 e 21 com severa alteração de cor, forma e posição, no qual a utilização destes procedimentos recuperou o sorriso e a auto-estima do paciente

Influence of ultrasonic setting on tensile bond strength of glass-ionomer cements to dentin.

PURPOSE: The aim of this study was to evaluate the influence of ultrasonic treatment on the bond strength of glass-ionomer cements to dentin. MATERIALS AND METHODS: Conventional (Fuji II: a; Ketac-Fil Plus: b), resin-modified (Fuji II LC Improved: c; Photac-Fil Quick Aplicap: d), and more viscous conventional (Ketac Molar: e) glass-ionomer cements were tested. Fifty human molars were sectioned mesiodistally, embedded in epoxy resin with exposed buccal or lingual surfaces, and ground to obtain a flat dentin surface. A matrix with a central orifice in the shape of an inverted truncated cone was built with a bovine tooth and positioned on the dentin surface. In the control groups, the materials were inserted into the matrix. In the test groups, the ultrasonic treatment was applied to the surface of the matrix and the surface of the glass-ionomer cements. The specimens were stored in deionized water for 24 h at 37 degrees C and subjected to bond strength tests. Data were analyzed using two-way ANOVA and Tukey's tests. RESULTS: The mean bond strengths in MPa for the control groups were: a: 2.21, b: 1.85, c: 8.65, d: 5.93, and e: 2.10. The results for the test groups were: a: 3.33, b: 2.19, c: 9.95, d: 6.10, and e: 2.65. Ultrasonic treatment statistically increased the tensile bond strength of all tested cements (p < 0.05). CONCLUSION: Ultrasonic treatment improved the bond strength of the glass-ionomer cements to dentin after 24 h.

Water sorption of resin-modified glass-ionomer cements photoactivated with LED.

The Light Emitting Diodes (LED) technology has been used to photoactivate composite resins and there is a great number of published studies in this area. However, there are no studies regarding resin-modified glass-ionomer cements (RMGIC), which also need photoactivation. Therefore, the aim of this study was to evaluate water sorption of two RMGIC photoactivated with LED and to compare this property to that obtained with a halogen light curing unit. A resin composite was used as control. Five specimens of 15.0 mm in diameter x 1.0 mm in height were prepared for each combination of material (Fuji II LC Improved, Vitremer, and Filtek Z250) and curing unit (Radii and Optilight Plus) and transferred to desiccators until a constant mass was obtained. Then the specimens were immersed into deionized water for 7 days, weighed and reconditioned to a constant mass in desiccators. Water sorption was calculated based on weight and volume of specimens. The data were analyzed by two-way ANOVA and Tukey test (p < 0.05). Specimens photocured with LED presented significantly more water sorption than those photocured with halogen light. The RMGIC absorbed statistically significant more water than the resin composite. The type of light curing unit affected water sorption characteristics of the RMGIC.

Microhardness of resin-based materials polymerized with LED and halogen curing units

O objetivo deste estudo foi avaliar a microdureza de materiais resinosos polimerizados com unidades de fotoativação LED (diodos emissores de luz) e halógena. Vinte espécimes cilíndricos (3,0 mm de diâmetro e 2,0 mm de altura) foram preparados para cada material testado (Z100, Definite e Dyract). Os espécimes foram fotoativados na face superior (topo), utilizando duas unidades de fotoativação (Ultraled and Curing Light 2500), com tempos de 40 s e 60 s. As medidas de dureza foram realizadas nas superfícies do topo e da base de cada espécime. A análise estatística foi realizada por ANOVA e teste de Tukey (p<0,05). Não houve diferença significante na dureza na face superior entre as unidades LED e halógena para a Z100 e o Dyract. Por outro lado, a dureza foi menor quando a Definite foi polimerizada com o LED do que com a unidade halógena. Na base, a dureza de todos os materiais foi menor com o LED do que com a unidade halógena. A Z100 apresentou maior dureza que o Dyract e que a Definite independentemente da unidade de fotoativação. Não houve diferença significante na dureza entre os dois tempos de fotoativação para a face superior. Na base, a dureza foi maior quando os materiais foram polimerizados por 60 s. O LED não foi capaz de produzir a mesma dureza que a unidade halógena nos materiais resinosos testados.

Tratamento de dentes anteriores desgastados pela associação de hábitos parafuncionais e erosão dentária / Treatment of anterior teth worn due to parafunction habits and dental erosion association

O estilo de vida moderno induziu a mudanças de hábitos alimentares que geraram novas consequências e riscos à saúde bucal, levando a uma crescente evidência de lesões não cariosas. O conhecimento da etiologia destas lesões e o avanço no desenvolvimento dos materiais e técnicas restauradoras permitem um tratamento rápido e eficiente no restabelecimento da estética e função. A correta orientação e cuidados do paciente podem prolongar a vida útil destas restaurações.

Clinical evaluation of multisurface ART restorations%Avaliação clínica de restaurações compostas ou complexas com a técnica do ART

O objetivo deste estudo foi avaliar o comportamento de dois cimentos de ionômero de vidro: um de alta viscosidade (Ketac Molar - ESPE) e um modificado por resina (Fuji VIII û GC) em restaurações envolvendo duas ou mais superfícies dentárias, confeccionadas pela técnica do Tratamento Restaurador Atraumático. Sessenta restaurações (30 com cada material) foram inseridas em estudantes (9-16 anos) por dois operadores. Após 6 meses, dois examinadores independentes avaliaram as restaurações de acordo com os critérios utilizados em trabalhos prévios semelhantes. Os dados foram analisados pelos testes de McNemar e Fischer. A porcentagem de sucesso do tratamento foi de 98,3%. Uma restauração (Ketac Molar) foi substituída por outro material e classificada como falha. As porcentagens de sucesso das restaurações foram de 100% e 96,6% para o Fuji VIII e Ketac Molar, respectivamente. Não houve diferença estatisticamente significante no sucesso das restaurações entre o baseline e 6 meses (p>0,05). Da mesma forma, não houve diferença estatística entre os materiais, tipos de cavidade ou entre operadores.(p>0,05). A técnica ART foi altamente apropriada e efetiva em restaurações envolvendo duas ou mais superfícies, após 6 meses. Os resultados mostraram um comportamento promissor com ambos os materiais

Clinical evaluation of multisurface ART restorations

O objetivo deste estudo foi avaliar o comportamento de dois cimentos de ionômero de vidro: um de alta viscosidade (Ketac Molar - ESPE) e um modificado por resina (Fuji VIII – GC) em restaurações envolvendo duas ou mais superfícies dentárias, confeccionadas pela técnica do Tratamento Restaurador Atraumático. Sessenta restaurações (30 com cada material) foram inseridas em estudantes (9-16 anos) por dois operadores. Após 6 meses, dois examinadores independentes avaliaram as restaurações de acordo com os critérios utilizados em trabalhos prévios semelhantes. Os dados foram analisados pelos testes de McNemar e Fischer. A porcentagem de sucesso do tratamento foi de 98,3%. Uma restauração (Ketac Molar) foi substituída por outro material e classificada como falha. As porcentagens de sucesso das restaurações foram de 100% e 96,6% para o Fuji VIII e Ketac Molar, respectivamente. Não houve diferença estatisticamente significante no sucesso das restaurações entre o baseline e 6 meses (p>0,05). Da mesma forma, não houve diferença estatística entre os materiais, tipos de cavidade ou entre operadores.(p>0,05). A técnica ART foi altamente apropriada e efetiva em restaurações envolvendo duas ou mais superfícies, após 6 meses. Os resultados mostraram um comportamento promissor com ambos os materiais.

Clinical evaluation of multisurface ART restorations.

The aim of this study was to evaluate the performance of two different glass-ionomer cements: a high-density (Ketac Molar - ESPE) and a resin-modified cement (Fuji VIII - GC) using the Atraumatic Restorative Treatment technique to restore multisurface cavities in permanent teeth. A total of 60 ART restorations (30 with each material) were placed in schoolchildren (9-16 years of age) by two operators. After a period of 6 months, two independent examiners evaluated 59 restorations according to the criteria used in previous ART studies. Data were submitted to McNemar and Fischer tests. The success rate of the treatment was 98.3%. One restoration (Ketac Molar) was replaced by another material and was recorded as failure. The success rates of the restorations were 100% and 96.6% for Fuji VIII and Ketac Molar, respectively. There was no statistically significant difference in the restorations success between baseline and 6 months (p>0.05). In the same way, no significant differences were found between materials, cavity types or operators (p>0.05). The ART approach was highly appropriate and effective in restorations involving two or more tooth surfaces, after 6 months. The results showed a promising performance of the ART technique with both materials.

Microhardness of resin-based materials polymerized with LED and halogen curing units.

The purpose of this study was to evaluate the microhardness of resin-based materials polymerized with a LED (light-emitting diode) light-curing unit (LCU) and a halogen LCU. Twenty cylindrical specimens (3.0 mm in diameter and 2.0 mm high) were prepared for each tested material (Z100, Definite and Dyract). Specimens were light-cured with two LCUs (Ultraled and Curing Light 2500) for either 40 or 60 s on their top surfaces. Hardness was measured on top and bottom surfaces of each specimen. Statistical analysis was done by ANOVA and Tukey's test (p<0.05). There was no significant difference in hardness between LED LCU and halogen LCU for Z100 and Dyract on top surface. Conversely, lower hardness was recorded when Definite was light-cured with the LED LCU than with the halogen lamp. On bottom surface, hardness was significantly lower for all materials light-cured with LED LCU. Z100 was harder than Dyract and Definite regardless of the light curing unit. There was no significant difference in hardness between the exposure times on top surface. Higher hardness was obtained when the materials were light-cured for 60 s on bottom surface. The tested LED was not able to produce the same microhardness of resin-based materials as the halogen LCU.

Aspectos relevantes na cimentação adesiva de restaurações indiretas sem metal / Important issues in adhesive cementation of metal free indirect restorations

A Odontologia Restautadora tem passado por uma grande evolução. Inúmeros materiais são lançados no mercado continuamente e, entre eles, encontram-se as porcelanas reforçadas e as resinas compostas de laboratório ou "indiretas" que por sua maior resistência, podem ser utilizadas sem infra-estrutura metálica. No entanto, paralelamente a essa evolução, o procedimento de fixação desses materiais deve ser atualizado, uma vez que o processo adesivo também sofreu modificações, exigindo o conhecimento profundo do substrato e do complexo envolvido (material restaurador indireto, cimento e adesivo). Assim, o objetivo deste trabalho de revisão é através da avaliação das características dos materiais, dar embasamento para a aplicação do procedimento (escolha do tipo de cimento e tratamento de superfície) mais apropriado para cada material

Diametral tensile strength and water sorption of glass-ionomer cements used in Atraumatic Restorative Treatment.

The purposes of this study were to evaluate the diametral tensile strength and the water sorption of restorative (Fuji IX and Ketac Molar) and resin-modified glass-ionomer luting cements (ProTec Cem, Fuji Plus and Vitremer) mixed at both manufacturer and increased powder: liquid ratio, for their use in the Atraumatic Restorative Treatment. A conventional restorative glass-ionomer (Ketac Fil) was used as control. Specimens (6.0 mm in diameter x 3.0 mm in height) were prepared and stored (1 hour, 1 day and 1 week) for a diametral tensile strength test. Data were subjected to two-way ANOVA and Tukey tests (p<0.05). For the water sorption test, specimens of 15.0 mm in diameter x 0.5 mm in height were prepared and transfered to desiccators until a constant mass was obtained. Then the specimens were immersed in deionized water for 7 days, weighed and reconditioned to a constant mass in desiccators. Data were subjected to one-way ANOVA and Tukey tests (p<0.05). Five specimens of each studied material and consistency were prepared for each test. The resin-modified glass-ionomer cements showed significantly higher strength than the conventional materials. Except for ProTec Cem, the diametral tensile strength of the resin-modified materials significantly increased from luting to restorative consistency. Except for ProTec Cem, the water sorption of the resin-modified glass ionomers was higher than the others. The water sorption of resin-modified materials at restorative consistency was significantly lower than at luting consistency. Resin-modified glass-ionomer luting cements mixed at increased powder: liquid ratio showed better properties than at luting consistency.