title: [The influence of polymerization time on physicochemical properties of the acrylic resin Vertex RS].
abstract: BACKGROUND
  A good denture can only be produced through proper actions during the clinical and laboratory stages of the production process. The aim of this study was to determine if a change in polymerization time affects the physicochemical properties of polymethacrylate material used for dentures.
  
  
  METHODS
  We examined the acrylic resin Vertex R.S. polymerized for 15, 25, 40, or 60 minutes. Palapress Vario was taken as reference material. Static bending, microhardness, surface wettability, and susceptibility to abrasion were determined.
  
  
  RESULTS
  The microhardness test showed that most of the samples had similar Vickers hardness (VS) values, except for the sample polymerized for 25 min. which demonstrated a significantly higher value. Grindability was affected by a change in polymerization time. Mass loss was greatest for samples polymerized for 15, 25, and 60 min. and smallest for Vertex 40 and Palapress Vario. We also observed differences in the wetting angle. Vertex 40 and 60 had a relatively low wetting angle signifying that longer polymerization time results in lower hydrophobicity of the material.
  
  
  CONCLUSIONS
  The present study has demonstrated that polymerization time has a significant effect on the hardness and some mechanical properties of the acrylic resin.
authors.affiliation: Zakład Protetyki Stomatologicznej Pomorskiej Akademii Medycznej w Szczecinie al. Powstańców Wlkp. 72, 70-111 Szczecin.
authors.forename: Bogumiła
authors.initials: B
authors.lastname: Fraczak
authors.forename: Ewa
authors.initials: E
authors.lastname: Sobolewska
authors.forename: Halina
authors.initials: H
authors.lastname: Ey-Chmielewska
authors.forename: Maria
authors.initials: M
authors.lastname: Skowronek
authors.forename: Stanisław
authors.initials: S
authors.lastname: Błazewicz
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D003778:Dentures; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry*
chemical_list: D000180:Acrylic Resins; D011108:Polymers