So there is a rather low level of evidence on the optimal overnight storage conditions for reducing microbial and yeast denture colonization and growth. The present study therefore aimed to analyze the role of the nocturnal storage state on plaque growth and composition on acrylic removable dentures in the absence of mechanical cleaning. More in particular, denture nocturnal preservations in tap water, dry or in tap water with added alkaline peroxide-based effervescent tablet were applied in a parallel-group randomized controlled trial of institutionalized elderly.