Majed Al-Akhali1, Mohamed Sad Chaar2, Adham Elsayed3, Abdulaziz Samran4, Matthias Kern3. 1. Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany; Department of prosthodontics, School of Dentistry, Ibb University, Ibb, Yemen. Electronic address: malakhali@proth.uni-kiel.de. 2. Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany. Electronic address: schaar@proth.uni-kiel.de. 3. Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany. 4. Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany; Department of prosthodontics, School of Dentistry, Ibb University, Ibb, Yemen; Department of Restorative and Prosthetic Dental Sciences, School of Dentistry, Dar Al-Uloom University, Riyadh, Saudi Arabia.
Abstract
OBJECTIVES: The purpose of this in vitro study was to evaluate the influence of thermodynamic loading on the durability and fracture resistance behavior of occlusal veneers fabricated from different biomedical dental CAD/CAM materials. METHODS: The occlusal surfaces of 64 extracted premolars were prepared in the enamel layer and restored with occlusal veneers with a fissure/cusp thickness of 0.5/0.8mm made from four different dental CAD/CAM materials: group LD lithium disilicate (e.max CAD), group LS zirconia-reinforced lithium silicate (Vita Suprinity), group PI polymer-infiltrated ceramic (Vita Enamic), and group PM polymethylmethacrylate PMMA (Telio CAD). The prepared teeth were etched with phosphoric acid. The occlusal veneers were then bonded using an adhesive luting system (Multilink Primer A/B and Multilink Automix luting resin). Half of the specimens were subjected to thermodynamic loading in a chewing simulator (1.2 million cycles at 98N). All specimens were quasi-statically loaded until fracture. The statistical analysis was made using the t-test and one-way ANOVA followed by the Tukey HSD test (α = 0.05). RESULTS: All aged specimens survived the thermodynamic loading. Thermodynamic loading significantly raised the fracture resistance in groups LS, PI, and PM (P < 0.03). Occlusal veneers made from lithium disilicate and zirconia-reinforced lithium silicate recorded higher fracture resistance than those made from polymer-infiltrated ceramic and PMMA resin. CONCLUSIONS: All tested dental CAD/CAM biomaterials exhibited a fracture resistance considerably exceeding the average occlusal force in the posterior dentition. Therefore, they might present a viable long-term treatment for restoring the occlusal surfaces of posterior teeth.
OBJECTIVES: The purpose of this in vitro study was to evaluate the influence of thermodynamic loading on the durability and fracture resistance behavior of occlusal veneers fabricated from different biomedical dental CAD/CAM materials. METHODS: The occlusal surfaces of 64 extracted premolars were prepared in the enamel layer and restored with occlusal veneers with a fissure/cusp thickness of 0.5/0.8mm made from four different dental CAD/CAM materials: group LD lithium disilicate (e.max CAD), group LS zirconia-reinforced lithium silicate (Vita Suprinity), group PI polymer-infiltrated ceramic (Vita Enamic), and group PM polymethylmethacrylate PMMA (Telio CAD). The prepared teeth were etched with phosphoric acid. The occlusal veneers were then bonded using an adhesive luting system (Multilink Primer A/B and Multilink Automix luting resin). Half of the specimens were subjected to thermodynamic loading in a chewing simulator (1.2 million cycles at 98N). All specimens were quasi-statically loaded until fracture. The statistical analysis was made using the t-test and one-way ANOVA followed by the Tukey HSD test (α = 0.05). RESULTS: All aged specimens survived the thermodynamic loading. Thermodynamic loading significantly raised the fracture resistance in groups LS, PI, and PM (P < 0.03). Occlusal veneers made from lithium disilicate and zirconia-reinforced lithium silicate recorded higher fracture resistance than those made from polymer-infiltrated ceramic and PMMA resin. CONCLUSIONS: All tested dental CAD/CAM biomaterials exhibited a fracture resistance considerably exceeding the average occlusal force in the posterior dentition. Therefore, they might present a viable long-term treatment for restoring the occlusal surfaces of posterior teeth.
Authors: Georgina García-Engra; Lucia Fernandez-Estevan; Javier Casas-Terrón; Antonio Fons-Font; Pablo Castelo-Baz; Rubén Agustín-Panadero; Juan Luis Román-Rodriguez Journal: Medicina (Kaunas) Date: 2020-03-18 Impact factor: 2.430