title: Influence of denture cleansers on the color stability of three types of denture base acrylic resin.
abstract: BACKGROUND
  Color stability is an important property of denture base acrylic resin. Color changes indicate aging or damaged dental materials. However, little information is available on the influence of denture cleansers on the color stability of acrylic resins.
  
  
  OBJECTIVE
  The purpose of this study was to determine the influence of denture cleansers on the color stability of 3 different types of acrylic resin.
  
  
  METHODS
  One heat-polymerized (HP) acrylic denture base resin (Acron), 1 autopolymerized (AP) hard direct reline acrylic resin (Denture Liner), and 1 visible-light-polymerized (VLP) hard direct reline acrylic resin (Tokuso Lite-Rebase) were evaluated. Five specimens of each material, 10 x 10 x 2 mm, were immersed in 1 of 9 commercial denture cleanser solutions or distilled water (control). Color changes were measured with a colorimeter and evaluated using the CIE L*a*b* colorimetric system. Data were analyzed using 1-way and 3-way ANOVA and the Student-Newman-Keuls test (alpha=.05).
  
  
  RESULTS
  Significant differences (P<.05) were found among the acrylic resins and denture cleansers in terms of color change (DeltaE) produced after 365 days. The DeltaE values of all denture base acrylic resins increased with time. The DeltaE of the AP acrylic resin was larger than that of the other acrylic resins. The least discoloration was found with ZTC denture cleanser (acid type). The influence of alkaline peroxide-type denture cleanser (Steradent) on the color stability of HP acrylic resin and AP acrylic resin was significantly greater (P<.05) than that of the other cleansers.
  
  
  CONCLUSIONS
  These results suggest that the color stability of denture base acrylic resins is influenced by polymerization type and the type of denture cleanser used.
authors.affiliation: Department of Prosthetic Dentistry, Graduate School of Biomedical Sciences, Hiroshima University, Minami-ku, Hiroshima, Japan. hong@hiroshima-u.ac.jp
authors.forename: Guang
authors.initials: G
authors.lastname: Hong
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Murata
authors.forename: YingAi
authors.initials: Y
authors.lastname: Li
authors.forename: Sinshuke
authors.initials: S
authors.lastname: Sadamori
authors.forename: Taizo
authors.initials: T
authors.lastname: Hamada
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D003819:Denture Bases; D003820:Denture Cleansers / Q000009:adverse effects*; D006801:Humans; D019904:Polymethyl Methacrylate; D017797:Prosthesis Coloring
chemical_list: D000180:Acrylic Resins; D003820:Denture Cleansers; D019904:Polymethyl Methacrylate