Does artificial aging affect mechanical properties of CAD/CAM composite materials

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Restorative Dentistry

Background:

• Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) materials are increasingly used for dental restorations.
• Understanding the long-term durability of these materials under various conditions is crucial for clinical success.
• Assessing flexural strength and reliability provides insight into material performance.

Purpose of the Study:

• To evaluate the flexural strength and Weibull characteristics of different CAD/CAM materials.
• To investigate the effects of various in vitro aging conditions on these properties.
• To compare the performance of Cerasmart™, Lava™ Ultimate, and Vita Enamic® under simulated oral environments.

Main Methods:

• Six in vitro aging conditions were applied: water storage, boiling, HCl exposure, autoclave, thermal cycling, and cyclic loading.
• Flexural strength was determined using a three-point bending test.
• Weibull distribution analysis assessed strength reliability, while coherence scanning interferometry evaluated surface topography.

Main Results:

• Water storage, autoclave, and thermal cycling significantly decreased flexural strength (p<0.05).
• Hydrochloric acid exposure and cyclic loading did not significantly affect flexural strength (p>0.05).
• Cerasmart™ and Lava™ Ultimate showed stable Weibull moduli, while Vita Enamic®'s reliability was affected by HCl exposure.

Conclusions:

• Artificial aging significantly reduces the flexural strength of novel CAD/CAM restorative materials.
• Cyclic loading and HCl exposure do not compromise the flexural strength or structural reliability of Cerasmart™ and Lava™ Ultimate.
• Material selection should consider the specific aging conditions they may encounter in vivo.