Investigation of Sintering Behavior, Crystallization, an‎d Mechanical Properties of Zirconia-Based Dental Composites Containing Li₂O–SiO₂–ZrO₂ Glass System

10/14/2026 12:00:00 AM

Dental ceramics are considered suitable alternatives to metal–ceramic systems due to their excellent aesthetics, translucency, an‎d biocompatibility. However, the brittleness an‎d the requirement of high sintering temperatures in stabilized zirconia have posed certain limitations. In this study, glass from the Li₂O–SiO₂–ZrO₂ system was employed as a sintering aid in combination with zirconia in order to improve the sintering process an‎d mechanical properties. Composite samples containing 2.5, 5, an‎d 7.5 wt% glass were prepared an‎d sintered at the optimized temperature of 1200 °C. The results showed that the addition of glass not only reduced the sintering temperature but also significantly increased the relative density an‎d flexural strength. The relative density of the glass-containing samples exceeded 97%, whereas pure YSZ requires much higher temperatures to achieve such densification. The flexural strength of pure zirconia (YSZ) was 125.18 MPa, which increased to 222.08 MPa an‎d 291.15 MPa for the composites with 2.5% an‎d 5% glass, respectively. The highest strength was observed in the sample with 5% glass addition, while at 7.5% glass the strength slightly decreased to 278.17 MPa, though it still remained higher than that of pure zirconia. These findings indicate that the addition of about 5 wt% Li₂O–SiO₂–ZrO₂ glass not only lowers the sintering temperature an‎d production costs but also enhances densification an‎d significantly improves the mechanical properties of zirconia-based dental composites.

زيركونياي پايدار شده، شيشه Li₂O–SiO₂–ZrO₂،سراميك دنداني، ريزساختار، استحكام خمشي

Stabilized Zirconia, Li₂O–SiO₂–ZrO₂ Glass, Dental Ceramic, Microstructure, Flexural Strength

Erfan Mahmoudian

Dr. Bijan Eftekhari Yekta Dr. Hamidreza Rezaei