Effect of Aging Treatments on Properties of Zirconia with Different Levels of Translucency

Document Type : Original Article


1 Dentist at Al-Zahraa University Hospital, Cairo, Egypt.

2 Professor of Crowns and Bridges department, Faculty of Dental Medicine For Girls, Al-Azhar University, Cairo, Egypt.

3 Lecturer of Crowns and Bridges department, Faculty of Dental Medicine for Girls, Al-Azhar University, Cairo, Egypt.


Purpose: The aim of this study was to evaluate the effect of low-temperature degradation(L-TD), and weathering process on translucency, surface roughness, biaxial-flexural strength, and crystalline phase identification of zirconia with different levels of translucency. Materials and methods: A total of ninety-six (N= 96) zirconia discs were fabricated in this study. Samples were divided into three groups (n=32 each) according to type of zirconia: IPS EmaxZirCAD of low, medium translucency and Incoris translucent Zirconia of high translucency. Translucency measurements, surface roughness, biaxial flexural strength determination and phase identification were carried out before and after aging. Each group was then sub-divided into 2 subgroups (n=16); (subgroup A): Low-temperature degradation(L-TD) at 134ºC, (subgroup B): Accelerated aging by means of a weathering process (WP). Results: Statistical analysis using two-way ANOVA test revealed that there was a significant effect on translucency parameter (TP), and L-TD showed statistically significantly higher mean TP than WP. L-TD showed significantly lower mean roughness than WP. There was no significant difference between biaxial flexural strength values before aging and after L-TD and WP. There was no phase transformation identified before and after aging indicating resistance to different types of artificial aging. Conclusions: Low-temperature degradation and weathering process affect translucency parameter and surface roughness of zirconiabased materials. Artificial aging doesn’t affect the biaxial flexural strength, and phase identification of different zirconia translucencies.


Main Subjects

Volume 10, Issue 2
Issue2 April-Restorative Dentistry issue (Removable Prosthodontics, Fixed Prosthodontics, Endodontics, Dental Biomaterials, Operative Dentistry)
April 2023
Pages 361-373