Mechanical properties of dental base materials

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Polymer Science

Background:

• Dental base materials are crucial for supporting restorations and protecting pulpal tissue.
• Understanding the mechanical properties of these materials over time is essential for clinical longevity.
• Seven common dental base materials were evaluated for their mechanical performance.

Purpose of the Study:

• To compare the compressive strengths and moduli of seven dental base materials at different time points.
• To assess the mechanical stability and performance of these materials under simulated physiological conditions.
• To identify materials with superior mechanical properties for dental applications.

Main Methods:

• Seven dental base materials (Dycal, VLC Dycal, Time-line, Vitrabond, Ketac Bond, Fuji Lining LC, XR-Ionomer) were tested.
• Cylindrical specimens (9 mm x 4 mm) were prepared and tested at 7 minutes, 24 hours, and 90 days.
• Compressive strength and modulus were measured using an Instron at a loading rate of 1.0 mm/min after specific storage conditions.

Main Results:

• Timeline (resin-based) demonstrated significantly higher compressive strength than all other materials at all time points.
• Dycal and VLC Dycal showed a significant decrease in compressive strength between 24 hours and 90 days.
• Fuji Lining LC exhibited superior compressive strength among the tested photosensitive glass-ionomer base/liners.
• Timeline had the highest compressive modulus at 7 minutes, while Ketac Bond showed a higher modulus at 24 hours and 90 days.

Conclusions:

• Timeline offers superior compressive strength and initial modulus compared to the evaluated glass-ionomers and calcium hydroxide materials.
• The mechanical properties of some materials, like Dycal, degrade over time, highlighting the importance of material selection.
• Fuji Lining LC is a promising photosensitive glass-ionomer base/liner with robust compressive strength.