Abstract
To evaluate and compare the surface roughness and optical properties in resinbased CAD/CAM materials during thermal aging. Methods: Lava Ultimate HT (3M ESPE, USA) and VITA Enamic HT (Vita Zahnfabrik, Germany) were selected for this study. Ten specimens for each group were prepared and polished. The surface roughness (Ra) and translucency (%) were measured by a 3D profilometer and spectrophotometer before and after the accelerated aging protocol (10,000 cycles, 5◦C, and 55◦C). The freeze-fracture surfaces of tested materials were observed by SEM. Results: Enamic HT had the lower surface roughness value of 82.56 ± 6.21 nm, while Ultimate HT owned the higher Ra of 125.89 ± 8.64 nm before thermal aging. Enamic HT had the lower transparency (%) of 55.02 ± 2.57, while Ultimate HT owned the higher transparency (%) of 58.89 ± 1.63 before thermal aging. Ra in tested CAD/CAM materials was greater than 0.2 μm after 10,000 thermocycles of 5/55◦C. Conclusions: The thermal aging led to a significant increase in surface roughness and a significant decrease in transparency in both CAD/CAM materials. Ultimate HT were significantly more translucent than Enamic HT before thermal aging, while Ultimate HT showed less translucent than Enamic HT after 10,000 thermocycles of 5/55◦C.
Keywords: Digital dentistry; surface roughness; translucency; thermal aging; CAD/CAM