Effects of temperature change and beverage on mechanical and tribological properties of dental restorative composites

• Dental materials were subjected to temperature change and immersed in two beverages.
• Surface properties were investigated for three dental composites and nanocomposites.
• Thermocycling was conducted for simulating temperature change in oral conditions.
• Thermocycling and immersion in each beverage had different effects on the samples.
• Nanohybrid and nano-composites had good performance under simulated oral conditions.

The aim of this study was to investigate the effects of temperature change and immersion in two common beverages on the mechanical and tribological properties for three different types of dental restorative materials. Thermocycling procedure was performed for simulating temperature changes in oral conditions. Black tea and soft drink were considered for beverages. Universal composite, universal nanohybrid composite and universal nanofilled composite, were used as dental materials. The nanoindentation and nanoscratch experiments were utilized to determine the elastic modulus, hardness, plasticity index and wear resistance of the test specimens.The results showed that thermocycling and immersion in each beverage had different effects on the tested dental materials. The mechanical and tribological properties of nanohybrid composite and nanocomposite were less sensitive to temperature change and to immersion in beverages in comparison with those of the conventional dental composite.