Related Experiment Video
Updated: May 2, 2026
Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
Hertzian contact response and damage tolerance of dental ceramics
Andrea Coldea1, Michael V Swain2, Norbert Thiel3
1Department of Oral Sciences, School of Dentistry, P.O. Box 647, 9001 Dunedin, New Zealand; Research and Development Department VITA Zahnfabrik, Ballyweg 6, 79713 Bad Saeckingen, Germany.
Objectives:
To determine the contact response and damage tolerance or strength degradation of a range of dental CAD/CAM ceramic materials including novel polymer-infiltrated-ceramic-network (PICN) materials by means of spherical indentations at various loads and indenter radii.
Methods:
The seven tested materials included Mark II, PICN test materials 1 and 2, In-Ceram Alumina, VM 9, In-Ceram YZ (Vita Zahnfabrik, Bad Saeckingen, Germany) and IPS e.max CAD, (Ivoclar Vivadent, Schaan, Liechtenstein). To evaluate the damage tolerance and role of indenter size, indentations with tungsten carbide spheres (0.5mm and 1.25mm radius) were placed on bending bars with varying loads (1.96-1000N). The indented bending bars were subsequently loaded to fracture in three-point bending. The contact induced damage was analyzed by light microscopy (LM) and SEM. The spherical contact response was measured on polished surfaces.
Results:
The initial strengths for the individual materials were found to reduce above specific indentation loads, which were a function of the indenter radius. Employing a 0.5mm radius sphere resulted in the following strength degrading loads and ordering of materials: VM9 (98N)
Significance:
This study aims to emulate the likely clinical behavior of contact loading by opposing cusps to dental restorative ceramic materials by utilizing spherical indentations at various loads and sphere diameters.
