Effect of surface treatment with remineralizing on the color stability and roughness of esthetic restorative materials / Efeito do tratamento de superfície na estabilidade de cor e aspereza em materiais restauradores estéticos

OBJECTIVES: The purpose of the study was to evaluate and compare the in vitro effect of fluoride varnish, APF gel and MI paste on the color stability and surface roughness of esthetic restorative materials. MATERIAL AND METHODS: 60 disks of each conventional glass ionomer and resin composite were made using molds of 1.2 cm x 2 mm. All the specimens were suspended in artificial saliva for 48 hours at 37ºC. Subsequently, fluoride varnish, APF gel, and MI paste were applied to all the subgroups except the controls. All the specimens were again suspended in artificial saliva and incubated at 37ºC for 24 hours. After incubation, they were cleaned using a toothbrush and toothpaste, and stored in the artificial saliva for 1 week. During this period, the specimens were subjected to color and surface roughness measurement. RESULTS: Measurements were expressed as mean ± standard deviation and compared between two groups by Student’s t test. One way ANOVA was used for multiple group comparison and Tukey’s test for pair wise comparison. CONCLUSION: The deterioration of GIC material was more rapid compared to composites when fluoride varnish, APF gels and GC Tooth Mousse were applied. The use of remineralizing agents on esthetic restorative materials causes changes in color and surface texture.

OBJETIVOS: A finalidade deste estudo foi avaliar e comparar o efeito in vitro do verniz com flúor, do gel APF e da pasta MI na estabilidade de cor e aspereza de superfícies de materiais restauradores estéticos. MATERIAL E MÉTODO: 60 discos de cimento de ionômero de vidro convencional e 60 de resina composta foram produzidos usando moldes de 1,2 cm x 2 mm. Todos os corpos de prova foram mantidos em saliva artificial por 48 horas a 37oC. Em seguida, verniz fluorado, gel APF e pasta MI foram aplicados a todos os subgrupos, com exceção do grupo controle. Todos os corpos de prova foram novamente imergidos em saliva artificial e incubados a 37oC por 24 horas. Após a incubação, eles foram limpos utilizando escova de dentes e pasta, sendo mantidos em saliva artificial por uma semana. Durante esse período, os corpos foram submetidos a medições de coloração e de aspereza de superfície. RESULTADOS: As medidas foram expressas como medianas +- de desvio-padrão e comparadas entre dois grupos pelo teste t de Student. ANOVA foi usada para comparação entre grupos e o teste de Tukey foi utilizado para comparações por pares. CONCLUSÃO: A deterioração do ionômero de vidro foi mais rápida quando comparada com os compósitos pela aplicação de verniz com flúor, gel APF e pasta GC dental. O uso de agentes remineralizantes nas restaurações estéticas pode causar alterações de cor e textura de superfície.

The effect of water purification systems on fluoride content of drinking water.

OBJECTIVE: The purpose of the present study was to determine the effect of different water purification systems on the fluoride content of drinking water and to compare the efficacy of these water purification systems in reducing the fluoride content. MATERIALS AND METHODS: Five different water purification systems were tested in this study. They were reverse osmosis, distillation, activated carbon, Reviva , and candle filter. The water samples in the study were of two types, viz, borewell water and tap water, these being commonly used by the people of Davangere City, Karnataka. The samples were collected before and after purification, and fluoride analysis was done using fluoride ion-specific electrode. RESULTS: The results showed that the systems based on reverse osmosis, viz, reverse osmosis system and Reviva showed maximum reduction in fluoride levels, the former proving to be more effective than the latter; followed by distillation and the activated carbon system, with the least reduction being brought about by candle filter. The amount of fluoride removed by the purification system varied between the system and from one source of water to the other. INTERPRETATION AND CONCLUSION: Considering the beneficial effects of fluoride on caries prevention; when drinking water is subjected to water purification systems that reduce fluoride significantly below the optimal level, fluoride supplementation may be necessary. The efficacy of systems based on reverse osmosis in reducing the fluoride content of water indicates their potential for use as defluoridation devices.