Fracture Resistance of New Metal-Free Materials Used for CAD-CAM Fabrication of Partial Posterior Restorations

Autores de INCLIVA

• Antonio Fons Font

  Autor

Participantes ajenos a INCLIVA

• Garcia-Engra, G
• Fernandez-Estevan, L
• Casas-Terron, J
• Castelo-Baz, P
• Agustin-Panadero, R
• Roman-Rodriguez, JL

Grupos y Plataformas de I+D+i

• Grupo de Investigación en Histopatología e Ingeniería Tisular

  

  Leading Researcher

  Manuel Mata Roig

Abstract

Background and Objectives: To evaluate in vitro the fracture resistance and fracture type of computer-aided design and computer-aided manufacturing (CAD-CAM) materials. Materials and Methods: Discs were fabricated (10 x 1.5 mm) from four test groups (N = 80; N = 20 per group): lithium disilicate (LDS) group (control group): IPS e.max CAD(R); zirconium-reinforced lithium silicate (ZRLS) group: VITA SUPRINITY(R); polymer-infiltrated ceramic networks (PICN) group: VITA ENAMIC(R); resin nanoceramics (RNC) group: LAVA (TM) ULTIMATE. Each disc was cemented (following the manufacturers' instructions) onto previously prepared molar dentin. Samples underwent until fracture using a Shimadzu(R) test machine. The stress suffered by each material was calculated with the Hertzian model, and its behavior was analyzed using the Weibull modulus. Data were analyzed with ANOVA parametric statistical tests. Results: The LDS group obtained higher fracture resistance (4588.6 MPa), followed by the ZRLS group (4476.3 MPa) and PICN group (4014.2 MPa) without statistically significant differences (p < 0.05). Hybrid materials presented lower strength than ceramic materials, the RNC group obtaining the lowest values (3110 MPa) with significant difference (p < 0.001). Groups PICN and RNC showed greater occlusal wear on the restoration surface prior to star-shaped fracture on the surface, while other materials presented radial fracture patterns. Conclusion: The strength of CAD-CAM materials depended on their composition, lithium disilicate being stronger than hybrid materials.

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

Keywords

• fracture resistance; resin nanoceramic; polymer-infiltrated ceramic network; lithium disilicate; zirconium-reinforced lithium silicate