Resistance to Fracture of Lithium Disilicate Feldspathic Restorations Manufactured Using a CAD/CAM System and Crystallized with Different Thermal Units and Programs

The aim of this study was to determine the resistance to fracture of feldspathic restorations with lithium disilicate and crystallized with different ovens and programs. Methods: Sixty monolithic restorations (LD) (EMAX CAD™ LT, Ivoclar-Vivadent™) were designed with the same parameters and milled with a CAD/CAM system (CEREC SW 5.1, CEREC MCXL, Dentsply-Sirona™, Bensheim). Each restoration was randomly assigned by randomization software (RANDNUM) to one of the three groups: a) (NF) Oven P310 (Ivoclar, Vivadent) normal crystallization program, b) (FF) Ivoclar P310 oven (Ivoclar-Vivadent™) rapid crystallization program, or c) (SF) SpeedFire oven (Dentsply-Sirona™). Results: There were statistically significant differences between the groups (ANOVA, p <0.05). The NF and FF groups showed the highest values of resistance to fracture, with statistically significant differences with the SF group. Conclusions: Using a furnace from the same dental company with predetermined programs from the material manufacturer, as well as using a predetermined program for rapid crystallization, has no effect on fracture resistance, and would save clinical time when performing ceramic restorations with lithium disilicate, while keeping their mechanical properties.

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Fracture Resistance of CAD/CAM-Fabricated Lithium Disilicate MOD Inlays and Onlays with Various Cavity Preparation Designs

Journal of Prosthodontics ◽

10.1111/jopr.12787 ◽

2018 ◽

Vol 28 (2) ◽

pp. e524-e529 ◽

Cited By ~ 3

Author(s):

Hyung-In Yoon ◽

Paul J. Sohn ◽

Sharon Jin ◽

Hawazin Elani ◽

Sang J. Lee

Keyword(s):

Fracture Resistance ◽

Lithium Disilicate ◽

Cavity Preparation ◽

Cad Cam

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Fracture Resistance of Titanium, Zirconia, and Ceramic-Reinforced Polyetheretherketone Implant Abutments Supporting CAD/CAM Monolithic Lithium Disilicate Ceramic Crowns After Aging

The International Journal of Oral & Maxillofacial Implants ◽

10.11607/jomi.7036 ◽

2019 ◽

Vol 34 (3) ◽

pp. 622-630 ◽

Cited By ~ 6

Author(s):

Saadet Atsü ◽

M Aksan ◽

Ali Bulut

Keyword(s):

Fracture Resistance ◽

Lithium Disilicate ◽

Implant Abutments ◽

Cad Cam ◽

Ceramic Crowns

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Zirconia Blocks Properties Used for CAD/CAM Dentistry Restorations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.804 ◽

2012 ◽

Vol 727-728 ◽

pp. 804-808 ◽

Cited By ~ 1

Author(s):

C. Santos ◽

Carlos Nelson Elias ◽

Andréa Matos Melo ◽

Sérgio Neves Monteiro

Keyword(s):

Mechanical Properties ◽

Fracture Resistance ◽

X Ray Diffraction ◽

X Ray ◽

M 10 ◽

All Ceramic ◽

Cad Cam ◽

Ceramic Blocks ◽

Bending Fracture ◽

Cam Systems

Several CAD/CAM systems are available to dental prosthesis laboratories that can be used to make all-ceramic copings and frameworks. In Brazil, the use of these systems presents low demand, due principally the high blocks ceramics cost used for theses systems. The ceramic blocks are imported. To increase the dental ceramic CAD/CAM applications is necessary develop and produce the ceramics blocks in Brazil. The purpose of the present work is to compare the mechanical properties of blocks of zirconium developed in the Brazil (ProtMat® Co) and imported (VITA). It was determined the mechanical and physics properties of the two types of blocks of zirconium stabilized with ytria. The blocks have been sinterized at 1530 °C and their mechanical and physics properties were measured. The x-ray diffraction analysis showed only tetragonal phase, which improve the blocks toughness. The Vickers hardness and fracture toughness were 1300HV and 9 MPam1/2, respectively. High bending fracture resistance was obtained for both materials with average values of 910MPa. The Weibull modulus was m=10 for Brazilian and imported blocks. It was not observed an important difference among the microstructures and mechanical properties of the analyzed zirconium blocks.

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

Medicina ◽

10.3390/medicina56030132 ◽

2020 ◽

Vol 56 (3) ◽

pp. 132

Author(s):

Georgina García-Engra ◽

Lucia Fernandez-Estevan ◽

Javier Casas-Terrón ◽

Antonio Fons-Font ◽

Pablo Castelo-Baz ◽

...

Keyword(s):

Hybrid Materials ◽

Fracture Resistance ◽

Lithium Disilicate ◽

Lithium Silicate ◽

Control Group ◽

Test Machine ◽

Occlusal Wear ◽

Significant Difference ◽

Computer Aided ◽

Cad Cam

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 × 1.5 mm) from four test groups (N = 80; N = 20 per group): lithium disilicate (LDS) group (control group): IPS e.max CAD®; zirconium-reinforced lithium silicate (ZRLS) group: VITA SUPRINITY®; polymer-infiltrated ceramic networks (PICN) group: VITA ENAMIC®; resin nanoceramics (RNC) group: LAVA™ ULTIMATE. Each disc was cemented (following the manufacturers’ instructions) onto previously prepared molar dentin. Samples underwent until fracture using a Shimadzu® 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.

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Influence of Ceramic Thickness and Ceramic Materials on Fracture Resistance of Posterior Partial Coverage Restorations

Operative Dentistry ◽

10.2341/12-459-l ◽

2015 ◽

Vol 40 (2) ◽

pp. 211-217 ◽

Cited By ~ 14

Author(s):

EM Bakeman ◽

N Rego ◽

Y Chaiyabutr ◽

JC Kois

Keyword(s):

Glass Ceramic ◽

Fracture Resistance ◽

Testing Machine ◽

Lithium Disilicate ◽

Ceramic Materials ◽

Tooth Structure ◽

Partial Coverage ◽

Significant Difference ◽

Ceramic Thickness ◽

Ceramic Restorations

SUMMARY This study evaluated the influence of ceramic thickness and ceramic materials on fracture resistance of posterior partial coverage ceramic restorations. Forty extracted molars were allocated into four groups (n=10) to test for two variables: 1) the thickness of ceramic (1 mm or 2 mm) and 2) the ceramic materials (a lithium disilicate glass-ceramic [IPS e.max] or leucite-reinforced glass ceramic [IPS Empress]). All ceramic restorations were luted with resin cement (Variolink II) on the prepared teeth. These luted specimens were loaded to failure in a universal testing machine, in the compression mode, with a crosshead speed of 1.0 mm/min. The data were analyzed using two-way analysis of variance and the Tukey Honestly Significantly Different multiple comparison test (α =0.05). The fracture resistance revealed a significant effect for materials (p<0.001); however, the thickness of ceramic was not significant (p=0.074), and the interaction between the thickness of ceramic and the materials was not significant (p=0.406). Mean (standard deviation) fracture resistance values were as follows: a 2-mm thickness of a lithium disilicate bonded to tooth structure (2505 [401] N) revealed a significantly higher fracture resistance than did a 1-mm thickness of leucite-reinforced (1569 [452] N) and a 2-mm thickness of leucite-reinforced ceramic bonded to tooth structure (1716 [436] N) (p<0.05). There was no significant difference in fracture resistance values between a lithium disilicate ceramic at 1-mm thickness (2105 [567] N) and at 2-mm thickness. Using a lithium disilicate glass ceramic for partial coverage restoration significantly improved fracture resistance compared to using a leucite-reinforced glass ceramic. The thickness of ceramic had no significant effect on fracture resistance when the ceramics were bonded to the underlying tooth structure.

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