OBJETIVO: O objetivo deste estudo foi avaliar o efeito do acabamento e polimento na estabilidade de cor da resina nanoparticulada Filtek Z350 XT em função de diferentes meios de imersão.MATERIAL E MÉTODO: Espécimes circulares (10 mm de diâmetro e 2 mm de espessura) foram preparados para cada grupo (n=6) utilizando uma matriz de aço inoxidável. Os grupos experimentais foram divididos de acordo com a presença ou ausência de acabamento e polimento e diferentes meios de imersão (saliva artificial, Suco artificial pronto KAPO(r) da Coca Cola(r) sabores: abacaxi, laranja, morango e uva). Os procedimentos de acabamento e polimento foram realizados com discos de lixa Super-Snap(r). Os espécimes permaneceram em saliva artificial por 24 horas (baseline) e foram submetidos à análise da cor usando um espectrofotômetro pelo sistema CIELab. Em seguida, foram imersos nos diferentes meios por 5 minutos, 3 vezes ao dia, com intervalos de 4 horas, durante 60 dias. Os espécimes foram mantidos em saliva artificial a 37±1°C nos intervalos entre as imersões. Após este período foi realizada nova leitura de cor. Os dados foram analisados com os testes de Kruskall-Wallis e Mann-Whitney. O nível de significância foi de 5%.RESULTADO: Os resultados mostraram que o acabamento/polimento não influenciou significativamente a estabilidade de cor da resina composta (p>0,05). Não houve diferença estatisticamente significativa na estabilidade de cor da resina estudada após a imersão nos diferentes meios (p>0,05).CONCLUSÃO: O acabamento e polimento e os meios de imersão não apresentaram influência na estabilidade de cor da resina nanoparticulada Filtek Z350 XT.

OBJECTIVE: The purpose of this study was to evaluate the effect of finishing and polishing on color stability of a nanofilled composite resin (Filtek Z350 XT) according to different immersion media.MATERIAL AND METHOD: Composite disks (10 mm diameter, 2 mm thickness) were prepared for each group (n = 6) using a stainless steel mold. The groups were divided according to the presence or absence of finishing and polishing procedure and immersion media (artificial saliva, artificial juice- KAPO(r) Coca-Cola(r)flavors: pineapple, orange, strawberry and grape). The finishing and polishing procedures were performed using Super -Snap(r) disks. The specimens were stored in artificial saliva for 24 hours (baseline) and were analyzed using a color spectrophotometer by CIELab system. Then, they were immersed in different media for 5 minutes, 3 times a day, every 4 hours during 60 days. They were stored in artificial saliva at 37 ± 1°C during the immersion intervals. After this time, new measure of color was performed. The data were analyzed using Kruskall-Wallis test and Mann- Whitney test. The significance level was 5%.RESULT: The results showed that the finishing/polishing not significantly influence the color stability of resin composite (p > 0.05). There was no statistically significant difference in the color stability of the studied resin after immersion in different media (p > 0.05).CONCLUSION: The finishing and polishing procedures and the immersion media did not have influence on color stability of nanofilled resin Filtek Z350 XT.

OBJECTIVE: This study evaluated the influence of light sources and immersion media on the color stability of a nanofilled composite resin. MATERIAL AND METHODS: Conventional halogen, high-power-density halogen and high-power-density light-emitting diode (LED) units were used. There were 4 immersion media: coffee, tea, Coke® and artificial saliva. A total of 180 specimens (10 mm x 2 mm) were prepared, immersed in artificial saliva for 24 h at 37±1ºC, and had their initial color measured with a spectrophotometer according to the CIELab system. Then, the specimens were immersed in the 4 media during 60 days. Data from the color change and luminosity were collected and subjected to statistical analysis by the Kruskall-Wallis test (p<0.05). For immersion time, the data were subjected to two-way ANOVA test and Fisher's test (p<0.05). RESULTS: High-power-density LED (ΔE=1.91) promoted similar color stability of the composite resin to that of the tested halogen curing units (Jet Lite 4000 plus - ΔE=2.05; XL 3000 - ΔE=2.28). Coffee (ΔE=8.40; ΔL=-5.21) showed the highest influence on color stability of the studied composite resin. CONCLUSION: There was no significant difference in color stability regardless of the light sources, and coffee was the immersion medium that promoted the highest color changes on the tested composite resin.

This study evaluated the finishing and polishing effect on the surface roughness and hardness of the Filtek Supreme XT, in fluoride solutions. Specimens were prepared (n = 140) with half of the samples finished and polished with Super-Snap® disks. The experimental groups were divided according to the presence or absence of finishing and polishing and immersion solutions (artificial saliva, sodium fluoride solution at 0.05% - manipulated, Fluordent Reach, Oral B, Fluorgard). The specimens remained immersed in artificial saliva for 24 hours and were then subjected to initial analysis (baseline) of surface roughness and Vickers microhardness. Next, they were immersed in different fluoride solutions for 1 min/day, for 60 days. Afterwards, a new surface roughness and microhardness reading was conducted. The data were submitted to a two-way ANOVA and Tukey's test (5% significance level). For the comparison of mean roughness and hardness at baseline and after 60 days, the paired Student t test was used. The results showed that the surface roughness and microhardness of the Filtek Supreme XT were influenced by the finishing and polishing procedure, independently of the immersion methods.

This study evaluated the effect of surface sealant on the translucency of composite resin immersed in different solutions. The study involved the following materials: Charisma, Fortify and coffee, Coca-Cola®, tea and artificial saliva as solutions. Sixty-four specimens (n = 8) were manufactured and immersed in artificial saliva at 37 ± 1 °C. Samples were immersed in the solutions for three times a day and re-immersed in artificial saliva until the translucency readings. The measurements were carried out at nine times: T1 - 24 hours after specimen preparation, T2 - 24 hours after immersion in the solutions, T3 - 48 hours and T4 to T9 - 7, 14, 21, 30, 60 and 90 days, respectively, after immersion. The translucency values were measured using a JOUAN device. The results were subjected to ANOVA and Tukey's test at 5%. The surface sealant was not able to protect the composite resin against staining, the coffee showed the strongest staining action, followed by tea and regarding immersion time, a significant alteration was noted in the translucency of composite resin after 21 days.

The aim of this in vitro study was to assess the effect of different fluoride-containing mouthrinses on the translucence of resin-modified glass ionomer cements, as a function of the restorative material used, the fluoride-containing solution employed and the time of immersion. Disks were prepared (10 mm × 2 mm) with the modified glass ionomer cements Vitremer (3M) and Fuji II LC (GC Co.), and immersed in three fluoride-containing solutions: Fluordent Reach (Johnson & Johnson), Fluorgard (Colgate-Palmolive) and Oral B (Gillette do Brasil Ltda). Translucence was measured with electrophoresis equipment (JOUAN) after different immersion times. The results obtained were submitted to ANOVA and Tukey's test, and a statistically significant decrease was observed in the translucence of the materials after immersion in the fluoride-containing solutions. Fuji II LC demonstrated the lowest alteration in translucence, independently of the solution employed. Fluorgard was the fluoride-containing mouthrinse that promoted the highest alteration. It can be concluded that the fluoride-containing mouthrinses influenced the translucence of the resin-modified glass ionomer cements.