title: Comparative evaluation of fluoride release from hydroxyapatite incorporated and conventional glass ionomer cement: an in vitro study.
abstract: BACKGROUND
  Glass ionomers are most commonly used esthetic restorative material, but has inferior mechanical properties. The search to improve its mechanical properties led to the use of hydroxyapatite (HA) whiskers as strengthening material for glass ionomer cement but its effect on fluoride release is still not clear.
  
  
  OBJECTIVE
  To evaluate and compare the fluoride release from HA incorporated glass ionomer and conventional glass ionomer cement (CGIC).
  
  
  METHODS
  This in vitro study comprised of total forty sample. Twenty Specimens of each HA incorporated glass ionomer and conventional glass ionomer were fabricated.
  
  
  METHODS
  Specimens were suspended individually in 25 mL of distilled water in a 50 mL plastic container and stored at 37°C. Distilled water was renewed every 24 h for 21 days. Fluoride release of sample was measured every 24 h for 7 days and weekly from 7 th day to 21 st day using Sension4 pH/ion selective electrode/mV meter.
  
  
  METHODS
  Descriptive statistics, Repeated Measure analysis of variance, Paired Sample t-test, Independent Sample t-test, scheffe post hoc test.
  
  
  CONCLUSIONS
  There was a significant decrease in the mean fluoride release from day 1 to day 21 for both the groups hydroxyapatite glass ionomer cement and conventional glass ionomer cement ([HA-GIC] and CGIC). Though, the mean values of HA-GIC were slightly lower than C GIC, there was no statistically significant difference in the mean fluoride release between HA-GIC and CGIC throughout the experimental period. Within the limitations of this experimental design, definitive conclusions cannot be drawn and further investigations at a molecular level are needed to evaluate the trend of fluoride release from this material.
authors.affiliation: Department of Pedodontics and Preventive Dentistry, Peoples College of Dental Sciences, Bhopal, India. dr_shilpi_tiwari@yahoo.co.in
authors.forename: S
authors.initials: S
authors.lastname: Tiwari
authors.forename: B
authors.initials: B
authors.lastname: Nandlal
mesh_terms: D004058:Diffusion; D017886:Durapatite / Q000737:chemistry*; D005459:Fluorides / Q000032:analysis / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D017736:Ion-Selective Electrodes; D008422:Materials Testing; D055595:Mechanical Phenomena; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D005899:Glass Ionomer Cements; D014867:Water; D017886:Durapatite; D005459:Fluorides