Comparative Quasi-Static Compressive Loading Performance of Two Ultrathin Ceramic Occlusal Veneers for Minimally...

Area of Science:

• Restorative Dentistry
• Biomaterials Science
• Dental Mechanics

Background:

• Minimally invasive dentistry increasingly utilizes ultrathin ceramic occlusal veneers (<0.5 mm) as alternatives to full-coverage crowns.
• Research on the mechanical performance of significantly thinned veneer restorations remains limited.
• This study investigates the mechanical behavior of 0.3 mm thick veneers.

Purpose of the Study:

• To compare the fracture resistance of 0.3 mm thick zirconia occlusal veneers versus lithium disilicate occlusal veneers.
• To evaluate the mechanical performance of ultrathin ceramic veneers under quasi-static compressive loading.
• To inform material selection for tooth-preserving restorative procedures.

Main Methods:

• Forty extracted human molars were prepared with a 0.3 mm occlusal reduction protocol.
• Restorations were designed and fabricated using CAD/CAM technology from either lithium disilicate (IPS e.max CAD) or zirconia (Prettau 3).
• Adhesive cementation was followed by fracture resistance testing under compressive loading until failure.

Main Results:

• The mean fracture load for lithium disilicate veneers was 481.45 ± 68.23 N.
• The mean fracture load for zirconia veneers was 720.93 ± 95.44 N.
• Lithium disilicate veneer fractures were catastrophic, while zirconia veneer fractures were not.

Conclusions:

• Zirconia occlusal veneers exhibited significantly higher fracture resistance than lithium disilicate occlusal veneers.
• Ultrathin zirconia veneers offer a more robust mechanical performance for minimally invasive restorations.
• Material choice is critical for the longevity of ultrathin ceramic veneers in restorative dentistry.