title: Effect of different mouthrinses on Knoop hardness of a restorative composite.
abstract: OBJECTIVE
  To evaluate the effect of mouthrinses on Knoop hardness number (KHN) of a restorative composite, at different exposure times.
  
  
  METHODS
  50 composite specimens (TPH Spectrum) were randomly allocated into five groups (n=10): distilled water; Listerine; Reach; Plax and Periogard. The samples were immersed daily for 14 days in 20 ml of the respective solution for 2 minutes twice a day (with a 12-hour interval between exposures). Measurements were carried out at four different times: 1 hour after sample preparation, 1, 7 and 14 days after the first immersion in the solutions.
  
  
  RESULTS
  Statistical analyses (Repeated Measures ANOVA and Tukey test at 0.05 significance level) showed significant differences among KHN of t wo experimental groups (mean values): Listerine (49.17) and Plax (51.14). There was n ointeraction between products and time, although the highest means were registered 24 hours after the first immersion for all tested groups.
authors.affiliation: Department of Restorative Dentistry, Piracicaba School of Dentistry, UNICAMP, SP, Brazil.
authors.forename: Andrea Nóbrega
authors.initials: AN
authors.lastname: Cavalcanti
authors.forename: Fabio Hiroyuki Ogata
authors.initials: FH
authors.lastname: Mitsui
authors.forename: Glaucia Maria Bovi
authors.initials: GM
authors.lastname: Ambrosano
authors.forename: Paula
authors.initials: P
authors.lastname: Mathias
authors.forename: Gisell Maria
authors.initials: GM
authors.lastname: Marchi
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D006244:Hardness / Q000187:drug effects; D006245:Hardness Tests / Q000379:methods; D009067:Mouthwashes / Q000494:pharmacology*; D011140:Polyurethanes / Q000737:chemistry*; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D009067:Mouthwashes; D011140:Polyurethanes