title: The influence of concentration of HEMA on degree of conversion and cytotoxicity of a dental bonding resin.
abstract: BACKGROUND
  This study evaluated the influence of 2-hydroxyethyl methacrylate (HEMA) on the degree of conversion (DC) and cytotoxicity of a dental bonding resin (DBR).
  
  
  METHODS
  A monomer mixture based on 61.9 wt% of bisphenol A glycidyl methacrylate (Bis-GMA), 36.9 wt% of triethylene glycol dimethacrylate (TEGDMA), and photoactivated using a binary system based on camphoroquinone (0.4 wt%) and ethyl 4-dimethylamine benzoate (0.8 wt%) was used as DBR. Different groups were obtained with addition of HEMA in crescent concentrations. DC was accessed by Real time Fourier Transform infrared spectroscopy. The cytotoxicity was evaluated with MTT assay. The DC and cytotoxicity were analyzed by one-way ANOVA followed by Tukey's Test (P<0.05).
  
  
  RESULTS
  A decrease in the DC was observed in the group with higher amount of HEMA. All tested-extracts were cytotoxic and there was an increased cytotoxic effect with higher HEMA addition.
  
  
  CONCLUSIONS
  Higher amount of HEMA in the DBR resulted in adverse effects, with more cell toxicity and lower degree of conversion.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Meridional Faculty (IMED), Passo Fundo, Brazil - rodrigo.varella@gmail.com.
authors.forename: Rodrigo V
authors.initials: RV
authors.lastname: De Carvalho
authors.forename: Luiz A
authors.initials: LA
authors.lastname: Chisini
authors.forename: Camila P
authors.initials: CP
authors.lastname: Ferruá
authors.forename: Ricardo D
authors.initials: RD
authors.lastname: Guiraldo
authors.forename: Alcides
authors.initials: A
authors.lastname: Gonini-Júnior
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Moura
authors.forename: Sandra B
authors.initials: SB
authors.lastname: Tarquínio
authors.forename: Flávio F
authors.initials: FF
authors.lastname: Demarco
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D001840:Dental Bonding; D006801:Humans; D012117:Resins, Synthetic; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D012117:Resins, Synthetic; D017438:Bisphenol A-Glycidyl Methacrylate