Color stability of relined dentures after chemical disinfection. A randomised clinical trial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processo FAPESP: 10/009167

Background: This randomised clinical study evaluated the effect of chemical disinfection with sodium perborate or chlorhexidine on the color stability of a hard chairside reline resin during six months.Methods: Hard chairside reline resin (Tokuyama Rebase Fast II) was used to reline complete dentures. After baseline color measurements, the patients were randomly divided into 3 groups (n = 15) and allocation was concealed with the use of the BioStat program. The dentures were cleansed according to three methods: CG (control group) - brushing with coconut soap and soft toothbrush, PG (Perborate group) - brushing according to previous methods and disinfection with warmed sodium perborate solution (Corega Tabs) for 5 min, once a day for 6 months and ChxG (Chlorhexidine Group) - brushing according to CG and disinfection with chlorhexidine digluconate 2% for 5 min once a day for 6 months. The data of Delta E*, Delta L*, Delta a* and Delta b* were analysed by 2-way repeated-measures ANOVAs and Tukey tests (alpha = 0.05).Results: There were significant differences amongst groups for Delta L, Delta a and Delta b. The time had a significant effect on Delta E and Delta L, for all groups evaluated.Conclusion: Changes in some color parameters (Delta L, Delta a and Delta b) of the reline resin Tokuyama Rebase were observed when the dentures were disinfected by perborate and chlorhexidine digluconate 2% solutions. The color stability of was also influenced by time, regardless of disinfection or nondisinfection.Clinical implications: Color stability of the denture materials is one variable to be considered when choosing disinfection methods. The data in this study will be useful to clinicians when they are selecting disinfectant solutions for disinfection of relined denture. (C) 2011 Elsevier Ltd. All rights reserved.