Related Experiment Video
Updated: Feb 5, 2026
Spark Plasma Sintering Apparatus Used for the Formation of Strontium Titanate Bicrystals
Published on: February 9, 2017
The Effect of Sintering Program on the Compressive Strength of Zirconia Copings
Amir Ali Reza Khaledi1, Mahroo Vojdani1, Mitra Farzin2
1Dept. of Prosthodontic, Biomaterials Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Statement Of The Problem:
Considering the limitations of conventional sintering of zirconium oxide (ZrO2) copings, shortening the sintering time can be proposed as an alternative method for making the copings.
Purpose:
This study aimed to assess the effects of sintering time on compressive strength of Yttria Tetragonal Zirconia Polycrystal (Y-TZP) copings.
Materials And Method:
Thirty copings of pre-sintered 3Y-TZP blanks were milled and sintered in a special furnace for three different durations (n=10 per group). The sintering time was 1 h 15 min for IPS e.max ZirCAD, 4 h 20 min for Speed ZrO2, and 7 h 20 min for the conventional ZrO2 group. The specimens were cemented on the brass dies by using conventional glass ionomer cement. The copings were vertically loaded until fracture by using a universal testing machine. The data were analyzed through one-way analysis of variance (ANOVA) and post hoc test to compare the mean differences of compressive strength yielded in three study groups (α=0.05).
Results:
The mean ± SD of compressive strength value was (3617 ± 543.54) N for IPS-e.maxZirCAD group, (2663 ± 508.11) N for Speed ZrO2 group, and (1662± 466.71 N) for conventional ZrO2 group. There were statistically significant differences among compressive strength values of the tested groups (p< 0.05). The highest compressive strength values were obtained from the IPS e.max ZirCAD group.
Conclusion:
Within the limitations of this in vitro study, it can be concluded that compressive strength of the zirconia copings is affected by the sintering time. High compressive strength of zirconia copings can be obtained by shortening the sintering time.
Related Concept Videos
01:30Relation Between Tensile Strength and Compressive Strength of Concrete
03:05Acid Strength and Molecular Structure
In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
01:27Coping Strategies: Problem Focused
For example, consider a student who struggles to understand their...
01:20Strength of Cement
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
01:14Amines to Alkenes: Cope Elimination
01:20Coping Strategies: Emotion Focused