Improvement of the mechanical and biological properties of bioactive glasses by the addition of zirconium oxide (ZrO₂) as a synthetic bone graft substitute

Abstract

In this study, mechanical properties of bioactive glass (BAG) synthetic bone graft substitute was improved by containing ZrO2 (ZrO2‐BAG), while maintaining advantageous biological properties of BAG such as osteoinductive and osteoconductive properties. The ZrO2‐BAG was produced by adding ZrO2 in the following proportions to replace Na2O in 45S5 BAG: 1% (Zr1‐BAG), 3% (Zr3‐BAG), 6% (Zr6‐BAG), and 12% (Zr12‐BAG). Properties including XRD, XPS, SEM, DSC, fracture toughness, and Vickers microhardness were evaluated. To assess the biological properties, Ca/P apatite formation, ion release, degradation rate, cell proliferation, ALP activity (ALP), and alizarin red S staining assay (ARS) were evaluated. Also, expression of osteogenic differentiation markers, Osteopontin (OPN), confirmed by immunofluorescence staining. Finally, an in vivo test was carried out to by implanting ZrO2‐BAG into the subcutaneous tissue of rats. The results of each test were statistically analyzed with one‐way ANOVA followed by Tukey's post hoc statistical test. Amorphous ZrO2‐BAG was successfully produced with increased mechanical properties as the ZrO2 content was increased. Additionally, ZrO2‐BAG exhibited a slower ion release and degradation rate compare to BAG without ZrO2. Bioactivity of ZrO2‐BAG was confirmed with apatite layer formed on the surface, significantly higher proliferation rate and significantly enhanced ALP and the degree of ARS of the cells compare to respective controls. The tissue reactions observed in the in vivo study showed neo‐formed vessels after implantation of ZrO2‐BAG.

Physical, Chemical, Mechanical, and Biological Properties of Four Different Commercial Root-End Filling Materials: A Comparative Study

“…Cell cytotoxicity of endodontic materials is of great concern because irritation of the surrounding tissue can affect periapical tissue regeneration [ 22 , 58 , 59 ]. In an in vitro study, after application in medium, MTA suffers a hydration reaction that results in the formation of calcium hydroxide and subsequent ionic dissociation into calcium and hydroxyl ions, which is responsible for an increase in pH value and an elevated calcium concentration in the cell medium [ 60 ].…”

“…According to the manufacturers, RM has less discoloration potential, is relatively cost-effective, and is easy to manipulate. Recently, a study showed that RM has similar biocompatibility to PR [ 15 , 16 , 19 , 20 , 21 , 22 , 23 ]. Dia Root Bio MTA (DR) is a newly improved calcium silicate-based MTA that is easy to manipulate and promotes cementogenesis and sealing capability inside the root canal system.…”

Toughening of Bioceramic Composites for Bone Regeneration

“…The fracture toughness of cortical bone (KIc = 2-12 MPa•m 0.5 ) is higher than that of ceramics or inorganic glass [160][161][162]. Numerous methods have been developed over time to measure the fracture toughness and hardness [163][164][165].…”

Revealing structural role of ZrO2 in silicate glasses from macroscale property by rigid‐unit packing fraction method

“…To understand the relationship between glass composition and performance, studies have been conducted to investigate the impact of ion substitution on the bioactivity and biological performance of bioactive glasses 4 . In particular, the inclusion of ZrO 2 at a desired level has been found to improve the bioactivity in certain glass compositions 5–8 . In this work, we explore new compositions with zirconia addition and combination of P 2 O 5 and high CaO content to increase the bioactivity of the glass.…”