title: Effect of Titanium dioxide nanoparticles on the flexural strength of polymethylmethacrylate: an in vitro study.
abstract: BACKGROUND
  To improve the flexural strength of polymethylmethacrylate (PMMA).
  
  
  OBJECTIVE
  To evaluate whether the incorporation of titanium dioxide nanoparticles in polymethylmethacrylate (PMMA) increases the flexural strength and to compare the different concentrations of titanium dioxide nanoparticles and its relation to flexural strength.
  
  
  METHODS
  Study was conducted in Sri Ramachandra University utilizing 40 specimens manufactured from clear heat polymerizing acrylic resin.
  
  
  METHODS
  Forty specimens of clear heat polymerizing acrylic resin of dimensions 65 Χ 10 Χ 3 mm as per ISO 1,567 standardization were fabricated and were grouped into A (CONTROL) with no titanium dioxide (TiO2) nanoparticles, B with 0.5 gms of TiO 2 nanoparticles, C with 1 gm of TiO 2 nanoparticles and D with 2.5 gms of TiO 2 nanoparticles added.The concentrations of titanium dioxide in each group were 1 wt%, 2 wt% and 5 wt%. Universal testing machine INSTRON was used to load at the center of the specimen with a cross head speed of 1.50 mm/min and a span length of 40.00 mm.
  
  
  METHODS
  ANOVA and multiple comparisons are carried out using the independent t-test.
  
  
  RESULTS
  The ANOVA result shows that there is a significant difference between the groups with respect to the mean flexural strength. Highest mean flexural strength is observed in Group D, while the lowest is seen in Group A. Independent t-test revealed that there was a statistical significance between Group A and Group D (0.041) and between Group B and Group D (0.028).
  
  
  CONCLUSIONS
  The results concluded that polymethylmethacrylate reinforced with different concentrations of titanium dioxide nanoparticles showed superior flexural strength than those of normal PMMA.
authors.affiliation: Final Year Undergraduate, Faculty of Dental Science, Sri Ramachandra University, Porur, Chennai, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Harini
authors.forename: Kasim
authors.initials: K
authors.lastname: Mohamed
authors.forename: T V
authors.initials: TV
authors.lastname: Padmanabhan
mesh_terms: D066298:In Vitro Techniques; D053768:Metal Nanoparticles; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D014025:Titanium