title: Effect of incorporation of 2-tert-butylaminoethyl methacrylate on flexural strength of a denture base acrylic resin.
abstract: Polymethyl methacrylate (PMMA) resins have commonly been used as a denture base material. However, denture bases may act as a reservoir for microorganisms and contribute to oral diseases in denture wearers. It is hypothesized that the 2-tert-butylaminoethyl methacrylate (TBAEMA) incorporated to acrylic resins should have antimicrobial activity related to the presence of amino groups on acrylic resin surface.
  
  
  OBJECTIVE
  The objectives of this study were to evaluate the presence of amino groups on acrylic resin surface and the influence on flexural strength after incorporation of TBAEMA.
  
  
  METHODS
  Six groups were divided according to the concentration of TBAEMA incorporated to acrylic resin (Lucitone 550): 0, 0.5, 1.0, 1.5, 1.75 and 2%. Specimens surface were evaluated by Electron Spectroscopy for Chemical Analysis (ESCA) to detect the presence of amino groups, represented by nitrogen ratios. Flexural strength of the specimens was tested and results were analyzed by ANOVA and Tukey's test (α=0.05).
  
  
  RESULTS
  Different nitrogen ratios were observed on specimen surfaces: 0, 0.13, 0.74, 0.66, 0.92 and 0.33% for groups 0, 0.5, 1.0, 1.5, 1.75, and 2%, respectively. Significant differences were found for flexural strength (p<0.001). The mean flexural strength values were 98.3±3.9, 93.3±3.2, 83.9±2.1, 82.8±5.2, 71.2±5.1 and 17.3±3.2 MPa for groups 0, 0.5, 1.0, 1.5, 1.75, and 2%, respectively.
  
  
  CONCLUSIONS
  Within the limitations of this study, the incorporation of TBAEMA results in the presence of the potentially antimicrobial amino groups on specimen surfaces, but affect the flexural strength, depending on the concentration of TBAEMA.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araraquara Dental School, São Paulo State University, Araraquara, SP, Brazil.
authors.forename: André Gustavo
authors.initials: AG
authors.lastname: Paleari
authors.forename: Juliê
authors.initials: J
authors.lastname: Marra
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Pero
authors.forename: Larissa Santana
authors.initials: LS
authors.lastname: Rodriguez
authors.forename: Adhemar
authors.initials: A
authors.lastname: Ruvolo-Filho
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Compagnoni
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000704:Analysis of Variance; D000890:Anti-Infective Agents / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003819:Denture Bases; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D020366:Methylmethacrylate / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D000180:Acrylic Resins; D000890:Anti-Infective Agents; D003764:Dental Materials; D008689:Methacrylates; C522816:poly(2-(tert-butylamino)ethyl methacrylate); D020366:Methylmethacrylate