ABSTRACT

Objective: The aim of this study was to evaluate the effect of two concentrations of chitosan
nanoparticles on the mechanical properties of heat polymerized acrylic resin before and after thermocycling.
The tested parameters were flexural strength and hardness.

Material and Methods: 120 specimens were prepared according to the specific dimension for
each test (flexural strength and micro hardness) and distributed into:
- Before thermocycling (control, chitosan nanoparticles with concentration 0.3% and 0.5%)
- After thermocycling (control, chitosan nanoparticles with concentration 0.3% and 0.5%)

Results: Flexural strength and micro hardness were tested for both groups. The data was collected
and statistically analyzed. Flexural strength was non-significantly increased for ratio of 0.3%
chitosan nanoparticles in comparison to control before and after thermo cycling and significantly
decreased for 0.5% chitosan nanoparticles before thermocycling and non-significant decrease after
thermocycling in comparison to control. For hardness showed non-significant decrease for both
concentrations and significant decrease for control after thermocycling

Conclusion: Adding chitosan nanoparticles to heat cured acrylic resin increased the flexural
strength for 0.3% ratio and non-significantly decreased for 0.5, while decreased non-significantly
micro hardness for both concentrations.