DOI: 10.4103/jips.jips_608_25 ISSN: 0972-4052

Comparative evaluation of 2-step and 3-step polishing systems on the surface roughness and flexural strength of lithium disilicate: An in vitro study

Rawan Abdullah Suliman Alrethia, Meshal Mohamed Suliman Alghofaili, Moataz Mohamed Amin Barakat, Vaibhav Awinashe, Ashwini Komalan, Abdullah Abdulaziz Alhablen
Show PDF Cite

Abstract

Aim:

The aim of this in vitro study was to investigate the effects of 2-step and 3-step polishing systems on the surface roughness and biaxial flexural strength of lithium disilicate ceramics after grinding.

Settings and Design:

Thirty-two 14 x 1.25 mm lithium disilicate (IPS e.max CAD) discs were divided into four groups ( n = 8): control (unmodified), ground-unpolished, ground-3-step polished (Shofu Zil Master), and ground-2-step polished (Toboom). A profilometer was used to quantify the surface roughness (Ra, µm), and ISO 6872 was followed to calculate the biaxial flexural strength (MPa).

Materials and Methods:

A profilometer was used to quantify the surface roughness (Ra, µm), and ISO 6872 was followed to calculate the biaxial flexural strength (MPa) of all the samples.

Statistical Analysis Used:

The data were analyzed through the IBM SPSS Statistics software package (Version 25.0). One-way Analysis of Variance (ANOVA) was used to check variations among the groups followed by the Tukey’s post hoc test (α=.05).

Results:

There were significant differences between the groups in both flexural strength and surface roughness ( P <.001). As compared to the control, the 3-step system (0.43 ± 0.21 µm) provided smoother surfaces than the 2-step system (0.78 ± 0.34 µm). The control group (1696.8 ± 486.9 MPa) and the 3-step group (1500.0 ± 306.2 MPa) had the highest flexural strength, whereas the 2-step group (951.3 ± 121.2 MPa) had the lowest values.

Conclusions:

The flexural strength and surface roughness of ground lithium disilicate were enhanced by both polishing systems; however, the 3-step system performed better and produced outcomes that were on par with unaltered ceramics.

More from our Archive