Effect of Electron Beam Irradiation or Flexural Strength of two Nanocomposites-an In vitro Study.

ABSTRACT

Aim: The aim of this study is to investigate whether dental nanocomposite Filtek Z350 XT and Ceram X-duo can benefit from electron beam irradiation in order to achieve increased flexural strength Place and Duration of Study Department of Conservative Dentistry and Endodontics, A. B. Shetty Memorial Institute of Dental Sciences, Nitte University, Deralakatte, Mangalore, India and Microtron Centre; Department of Physics Mangalore University; Mangalore, India between May 2011 to March 2014. Materials and Methods: Materials were prepared on rectangular bar shaped specimens of 25-×2-×2-mm according to ISO standard -4049. Electron beam irradiation dose selected for the study were 1KGy, 3KGy and 5KGy. In total, 48 specimens were fabricated and divided into 4 groups based on radiation dose group I (non-radiated), group II (1KGy), group III (3KGy), group IV (5KGy) with 12 specimens in each. After 24 hours, specimens were subjected to 3-point bend test on a universal uniaxial servo mechanical testing machine. Statistical Analysis: Performed using one way ANOVA and inter group comparisons were done using tukeys multiple comparision. ‘P’ value<0.05 was considered statistically significant. Results: Flexural strength of Filtex Z350 XT before radiation was170.89±9.07.Flexural strength of Filtex Z350 XT after irradiation with 1KGy, 3KGy and 5KGy was found to be 269.06±94.91, 326.53±54.74 and 377.64±74.5 respectively. P value statistically significant (P<0.0001). Flexural strength of Ceram X duo before radiation was120.14±7.12.Flexural strength of Ceram X duo after irradiation with 1KGy, 3KGy and 5KGy was found to be 206.27±76.38, 177.31±67.35 and 229.33±59.15 respectively. P value statistically significant (P<0.0001). Conclusion: It can be concluded that electron beam irradiation can be used as a tool to modify the present day dental materials for enhancing their mechanical properties.