Comparison of the Mechanical Properties of Recent Nanofill and Nanohybrid Composite

Objectives: The purpose of this study is to evaluate the degree of conversion (DC), shear bond strength (SBS), compressive strength (CS), tensile strength (TS) and flexural strength (FS) of two recent resin-based composite materials which are nanofill composite (FiltekTM bulk fill) and nanohybrid composite(Filtek TM Z250XT) and to correlate the findings with the mechanical properties of these two restorative materials.
Methods: Two resin-based materials (FiltekTM bulk fill and Filtek TM Z250XT) were tested. 20 Samples of each type of selected composite were prepared. Specimens were immersed in distilled water for 24 hours. Then, they were subjected to degree of conversion , shear bond strength, compressive strength, tensile strength and flexural strength measurements. The obtained data were tabulated for statistical analysis and significant was set at P ≤ 0.05. The t-test was used to detect the significant difference among the variables tested in this study.
Results: FiltekTM bulk fill was higher than Filtek TM Z250XT in all tested mechanical properties. Shear bond strength (Bulk fill = 16.4+0.9Mpa, TM Z250XT =11.2+1.1Mpa). Compressive strength strength (Bulk fill = 75.3+3.3 Mpa, TM Z250XT =63.8+1.1 Mpa). Flexural strength strength (Bulk fill = 22.9+1.0 Mpa, TM Z250XT =18.1+1.1 Mpa) .Degree of conversion (Bulk fill = 85.2%+1.253 , TM Z250XT =67.2%+1.423) . Tensile strength (Bulk fill = 9.8+0.8 Mpa , TM Z250XT =6.36+0.9 Mpa) . Statistical significance was detected in all tests (P<0.05).
Conclusions: The study result showed superior mechanical properties of FiltekTM bulk fill than Filtek TM Z250XT and this indicates that the FiltekTM bulk fill is better in high stress area to withstand the higher forces.