title: Effect of resin composites with sodium trimetaphosphate with or without fluoride on hardness, ion release and enamel demineralization.
abstract: OBJECTIVE
  To evaluate the effect of the addition of sodium trimetaphosphate (TMP) with or without fluoride on enamel demineralization, and the hardness and release of fluoride and TMP of resin composites.
  
  
  METHODS
  Bovine enamel slabs (4 x 3 x 3 mm) were prepared and selected based on initial surface hardness (n = 96). Eight experimental resin composites were formulated, according to the combination of TMP and sodium fluoride (NaF): TMP/NaF-free (control), 1.6% sodium fluoride (NaF), and 1.5%, 14.1% and 36.8% TMP with and without 1.6% NaF. Resin composite specimens (n = 24) were attached to the enamel slabs with wax and the sets were subjected to pH cycling. Next, surface and cross-sectional hardness and fluoride content of enamel as well as fluoride and TMP release and hardness of the materials were evaluated. Data were statistically analyzed using ANOVA (P < 0.05).
  
  
  RESULTS
  The presence of fluoride in enamel was similar in fluoridated resin composites (P > 0.05), but higher than in the other materials (P < 0.05). The combination of 14.1% TMP and fluoride resulted in less demineralization, especially on lesion surface (P < 0.05). The presence of TMP increased fluoride release from the materials and reduced their hardness.
authors.forename: Adelisa Rodolfo Ferreira
authors.initials: AR
authors.lastname: Tiveron
authors.forename: Alberto Carlos Botazzo
authors.initials: AC
authors.lastname: Delbem
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gaban
authors.forename: Kikue Takebayashi
authors.initials: KT
authors.lastname: Sassaki
authors.forename: Denise
authors.initials: D
authors.lastname: Pedrini
mesh_terms: D000818:Animals; D002327:Cariostatic Agents / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D003743:Dental Enamel / Q000187:drug effects* / Q000648:ultrastructure; D003764:Dental Materials / Q000737:chemistry*; D004058:Diffusion; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D010758:Phosphorus / Q000032:analysis; D011122:Polyphosphates / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D012969:Sodium Fluoride / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D013997:Time Factors; D017001:Tooth Demineralization / Q000473:pathology / Q000503:physiopathology*
chemical_list: D002327:Cariostatic Agents; D003188:Composite Resins; D003764:Dental Materials; D011122:Polyphosphates; D010758:Phosphorus; D012969:Sodium Fluoride; C009293:trimetaphosphoric acid