Compressive Strength of Glass-Hybrid Material Modified With TiO2 and HAp
Objectives: The objective of this research was to investigate compressive strength, breaking strength and compressive modulus of glass hybrid restorative material modified with TiO2 nano particles (NP), hydroxyapatite (HAp) particles (<45µm) and a combination of TiO2 NP and HAp particles.
Methods: Materials used in the study were glass hybrid material Equia Forte HT Fil (GC Corporation, Tokyo, Japan), TiO2 powder P25 (Degussa, Essen, Germany) and HAp synthesized from cuttlefish bone and grounded in a mortar to obtain HAp powder. There were four groups of samples (N=10): (i) Equia Forte HT control group; (ii) modified with 3 wt% TiO2; (iii) modified with 3 wt% HAp and (iv) modified with 1.5wt%TiO2 + 1.5wt%HAp. Measurements were performed in the universal testing machine and compressive strength (CS), breaking strength (BS) and compressive modulus (CM) were calculated for the four groups of samples. Statistical analysis was performed using ANOVA and Tukey test and the equality of variances was tested using Leven test.
Results: CS, BS and CM differed significantly between the groups (ANOVA test, p = 0.008, p = 0.004 and p = 0.0001, respectively).
CS and BS were significantly higher in 3wt% HAp group than in other two experimental groups (3wt%TiO2 and 1.5wt%TiO2 + 1.5wt%HAp groups). CM was significantly higher in 3wt% HAp group compared to all other groups.
Conclusions: Equia Forte HT Fil with 3wt% HAp micro particles added to the original powder showed improved CS and BS, while CM was significantly higher compared to the control group.