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

Abstract

Objective: To compare the color stability, translucency, and biaxial flexural strength (BFS) of differently glazed advanced lithium disilicate (ALDS) with those of lithium disilicate (LDS) and zirconia-reinforced lithium silicate (ZLS) after coffee thermocycling.Materials and methods: Forty disk-shaped specimens were prepared from three lithium silicate based materials (CEREC Tessera, ALDS; IPS e.max CAD, LDS; Vita Suprinity, ZLS). ALDS specimens were divided into two subgroups according to glazing procedures (reduced glaze duration, ALDS-S and normal glaze duration, ALDS-N), while LDS and ZLS specimens were crystallized and glazed. Color coordinate measurements were performed before and after coffee thermocycling. Color differences (ΔE 00 ) and relative translucency parameters (RTP) were calculated. Specimens were then subjected to BFS test. Statistical analysis was performed by using 1-(ΔE 00 and BFS) and 2-way (RTP) ANOVA tests (α = 0.05).Results: ΔE 00 values of tested materials were similar (df = 3, F = 0.150, p = 0.929). Two-way ANOVA showed the significant effect of material type, coffee thermocycling, and the interaction between these parameters on RTP values (p < 0.001). Both before and after thermocycling, LDS had the highest (p ≤ 0.001) and ZLS had the lowest (p < 0.001) RTP values, while ALDS-N had higher RTP than ALDS-S (p ≤ 0.001). Among tested materials, only LDS had similar RTP values before and after thermocycling (p = 0.865) as the other materials had lower RTP values after thermocycling (p < 0.001). ALDS-N had higher BFS values than ALDS-S (p = 0.005), while LDS had similar values to ALDS specimens (p ≥ 0.201). ZLS had the highest BFS (p ≤ 0.007).Conclusions: ALDS had comparable values to those of other materials. However, reduced glazing duration resulted in decreased translucency and BFS of ALDS.Clinical significance: ALDS may be an appropriate restorative material for those patients with increased coffee consumption considering its color stability and ability to maintain translucency, particularly when glazed by using a conventional porcelain furnace.

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

“…Light blue and dark blue instruments (surface finishing) of the polishing assortment were used at 10,000 rpm, whereas the polishing paste was applied by using a brush at 8000 rpm (high gloss polishing). 18 Baseline color coordinate (L*, a*, and b*) measurements were performed using a spectrophotometer (CM-26d; Konica Minolta), 8,9 which has a diffused illumination integrating sphere system (8 • viewing) and two specular component modes (specular component included and excluded). It allows either medium (12/8 mm illumination/measurement area) or small area view (6/3 mm illumination/measurement area) and uses the CIE Standard 2 • or 10 • human observer characteristics along with a number of different illuminants in its color estimations.…”

“…Ever since the introduction of IPS e.max CAD (Ivoclar) in 2006, 1 lithium disilicate glass–ceramics have been the most preferred restorative material among glass–ceramics 3,4 due to their mechanical, optical, and chemical properties 5,6 . However, the dental market is constantly evolving, and new lithium disilicate glass–ceramics are being rapidly introduced 7,8 . Nano‐lithium disilicate glass–ceramic (Amber Mill, HASSBio Corp) is one of the recently marketed products, 9 which has a unique feature that allows it to adjust its translucency depending on the crystallization process 10 .…”

“…5,6 However, the dental market is constantly evolving, and new lithium disilicate glass-ceramics are being rapidly introduced. 7,8 Nano-lithium disilicate glass-ceramic (Amber Mill, HASSBio Corp) is one of the recently marketed products, 9 which has a unique feature that allows it to adjust its translucency depending on the crystallization process. 10 Another novel material is fully crystallized lithium disilicate glass-ceramic (Initial LiSi Block; GC Corp), which does not require any firing (crystallization or glazing) process and can be delivered after polishing.…”

Effect of aging and fiber‐reinforcement on color stability, translucency, and microhardness of single‐shade resin composites versus multi‐shade resin composite

“…After baseline measurements, the specimens were subjected to 10,000 cycles of thermocycling between 5 and 55 C and a dwell time of 30 s (THE 1100; SD Mechatronik, Feldkirchen-Westerham, Germany), as reported in previous studies. 27,28 After thermocycling, the color, TP, and microhardness measurements were repeated. Subcommands listed under univariate designs are applicable to all analyses, while the subcommands listed for multivariate designs can be utilized in any multivariate analysis, including those with repeated measures.…”

“…[22][23][24][25][26] In vitro studies use thermal cycling to simulate the aging process of dental materials. 27,28 Simulation of hydrolytic degradation that occurs during combined use in their structure can be attempted in thermal cycling. 29,30 Surface hardness is a crucial mechanical property that is closely associated with the durability of dental studies.…”