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

Abstract

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.

Translucency, color stability, and biaxial flexural strength of advanced lithium disilicate ceramic after coffee thermocycling

“…Among the available ceramic materials, glass‐matrix ceramics have the advantages of translucency and biocompatibility. However, their brittle nature created the need for reinforcements for improved physical properties, which led to the introduction of millable lithium disilicate (LDS) glass ceramic (IPS e.max CAD; Ivoclar Vivadent) in the early 2000s 2,6,7 …”

“…However, their brittle nature created the need for reinforcements for improved physical properties, which led to the introduction of millable lithium disilicate (LDS) glass ceramic (IPS e.max CAD; Ivoclar Vivadent) in the early 2000s. 2,6,7 Even though lithium disilicate glass ceramic has increased its popularity significantly ever since and became the material of choice compared with other glass-matrix ceramics, 8 new materials are frequently marketed. [9][10][11] Zirconia-reinforced lithium silicate glass ceramic (ZLS) has been launched as a unique material that combines the advantages of lithium disilicate and zirconia [12][13][14][15][16] due to 10 wt% of zirconium dissolved in its glassy matrix.…”

Optical properties, biaxial flexural strength, and reliability of new‐generation lithium disilicate glass‐ceramics after thermal cycling

“…Computer‐aided design and computer‐aided manufacturing (CAD–CAM) technologies have facilitated the use of various restorative materials, including glass–ceramics 1 . Glass–ceramics are widely preferred due to their biocompatibility, high translucency, and pleasing esthetics 2 .…”

“…Glass–ceramics are widely preferred due to their biocompatibility, high translucency, and pleasing esthetics 2 . In addition, the inherent brittleness of glass–ceramics is improved with the addition of various reinforcing particles, such as lithium disilicate 1 …”

“…Computer-aided design and computer-aided manufacturing (CAD-CAM) technologies have facilitated the use of various restorative materials, including glass-ceramics. 1 Glassceramics are widely preferred due to their biocompatibility, high translucency, and pleasing esthetics. 2 In addition, the inherent brittleness of glass-ceramics is improved with the addition of various reinforcing particles, such as lithium disilicate.…”