title: Effects of cleansing methods on 3-D surface roughness, gloss and color of a polyamide denture base material.
abstract: OBJECTIVE
  The purpose of this study was to determine the effects of two denture cleansing methods on 3-D surface roughness, gloss and color of denture base materials.
  
  
  METHODS
  Thirty disks from nylon (Valplast) and 30 from heat-polymerized acrylic denture base material (Paladon 65) were made and 10 of each material were immersed in water (control), Val-Clean (peroxide cleanser) and Corega Extradent (peroxide cleanser) plus microwaving for a period simulating 30 days of daily cleansing. 3-D surface roughness, gloss and color parameters were measured before and after cleansing using an interferometric profilometer, a gloss meter and a colorimeter. The results were statistically analysed by regression, paired-t, Mann-Whitney and Kruskal-Wallis tests at α = 0.05 level of significance.
  
  
  RESULTS
  The results showed significant differences at baseline in L* and b* parameters between materials (p < 0.01), with a significantly lower gloss (p < 0.05) and higher roughness (p < 0.05) for Valplast. After cleansing, Δϵ* was significantly greater in Valplast than Paladon 65 (p < 0.05). Gloss of both materials decreased significantly within the Corega Extradent plus microwave solution (p < 0.05), while roughness increased significantly only for Paladon 65 (p < 0.05).
  
  
  CONCLUSIONS
  Valplast was found to have a significantly lower gloss and a higher roughness than Paladon 65 before cleansing. After cleansing, ΔE* increased more in Valplast than in Paladon 65, gloss of both materials decreased and roughness only of Paladon 65 increased within the Corega extradent plus microwaving method.
authors.affiliation: Department of Prosthodontics.
authors.forename: Nick C
authors.initials: NC
authors.lastname: Polychronakis
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Polyzois
authors.forename: Panagiotis E
authors.initials: PE
authors.lastname: Lagouvardos
authors.forename: Triantafillos D
authors.initials: TD
authors.lastname: Papadopoulos
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D003116:Color; D003124:Colorimetry / Q000295:instrumentation; D003764:Dental Materials / Q000737:chemistry*; D003819:Denture Bases; D003820:Denture Cleansers / Q000737:chemistry*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007368:Interferometry / Q000295:instrumentation; D008027:Light; D008422:Materials Testing; D008872:Microwaves; D009757:Nylons / Q000737:chemistry; D010545:Peroxides / Q000737:chemistry; D019904:Polymethyl Methacrylate; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D003764:Dental Materials; D003820:Denture Cleansers; D009757:Nylons; D010545:Peroxides; D014867:Water; C024149:paladon; D019904:Polymethyl Methacrylate; C075333:Extradent
keywords: PMMA; denture cleansers; microwave irradiation; nylon