Impact of artificial aging by thermocycling on edge chipping resistance and Martens hardness of different dental CAD-CAM restorative materials

Hampe, Rüdiger; Theelke, Björn; Lümkemann, Nina und Stawarczyk, Bogna (2021): Impact of artificial aging by thermocycling on edge chipping resistance and Martens hardness of different dental CAD-CAM restorative materials. In: Journal of Prosthetic Dentistry, Bd. 125, Nr. 2: S. 326-333

Abstract

Statement of problem. The selection of an appropriate restorative material based on fracture behavior is important for the marginal integrity of a dental restoration. For computer-aided design and computer-aided manufacturing (CAD-CAM) restorative materials, information regarding their edge chipping resistance is scarce. Purpose. The purpose of this in vitro study was to determine the edge chipping resistance (ECR) and Martens hardness (HM) of 6 different dental CAD-CAM restorative materials before and after thermocycling. Material and methods. Four composite resin materials including Brilliant Crios;Cerasmart, an experimental material;Lava Ultimate, a polymer-infiltrated ceramic-network (PICN) material (VITA Enamic), and a glass-ceramic control (IPS Empress CAD) were tested. The specimens were tested before and after thermocycling (30000 times, 5 degrees C/55 degrees C). The ECR was measured for each material (n=25) and related to the point of loading and to the maximum chipping depth. HM was determined for each material (n=25). The Kruskal-Wallis and Mann-Whitney U tests were used to compare materials (alpha=.05). The impact of thermocycling was analyzed by using the Wilcoxon test (alpha=.05). The correlations between all parameters were calculated by using the Spearman-Rho test (alpha=.05). For fractographic analysis of chip patterns, chipped surfaces were analyzed by laser scanning microscopy. Results. For ECR and HM, the materials showed different values. ECRmd and ECRpl showed a positive correlation, but both showed a negative correlation to HM. The materials showed a different chip size (P<.001). Chip patterns revealed brittle material behavior in all cases. Conclusions. All tested CAD-CAM materials behaved as brittle materials, but HM and ECR differed among the materials. The control glass-ceramic material showed the highest values for HM, followed by the PICN material. ECR values revealed the opposite order of materials, with the highest for composite resins. Artificial aging by thermocycling affected all dental CAD-CAM restorative materials. Especially for composite resin materials, ECR changed after aging.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0022-3913
• Sprache: Englisch