講演情報
[P-84（E）]Development of Novel Zirconia: Enhancing Mechanical Properties and Biological Activity for Advanced Biomedical Applications
*Zhiwei Zhou1, Kosuke Nozaki1, Huichuan Xu1, Satsuki Tanaka1, Masanao Inokoshi2, Noriyuki Wakabayashi1 (1. Advanced Prosthodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo, 2. Oral Devices and Materials, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo)
[Objective]
This study investigated the mechanical properties of 1.5 mol% yttria-stabilized tetragonal zirconia (1.5YSZ) after sandblast and acid etch (SLA) treatment and aging and assessed its early osteogenic potential for dental implant applications.
[Method]
3YSZ (TZ-3YSB-E, Tosoh Corp., Tokyo, Japan) was sintered at 1500°C, while 1.5YSZ (Zgaia 1.5Y-HT, Tosoh Corp.) was sintered at 1250-1400°C. Surface modification involved alumina particle sandblasting and 40% hydrofluoric acid (HF) etching. Aging was simulated by exposure to 134°C for a duration of 50 hours. Characterization included scanning electron microscopy (SEM), 3D laser microscopy, wettability analysis, and X-ray diffraction (XRD) to assess low-temperature degradation (LTD) resistance. Mechanical properties were tested for biaxial flexural strength and fracture toughness (single-edge precracked beam method). MC3T3-E1 cells were used to evaluate proliferation, differentiation, and mineralization.
[Results and Discussion]
Higher sintering temperatures increased grain size and SLA treatment created nanoscale surface features. SLA also increased monoclinic phase content, but 1.5Y-1250 showed minimal monoclinic fraction during LTD. Aging increased the monoclinic phase content in all groups but did not affect surface roughness. SLA modification generated a super hydrophilic surface of all groups with no significant differences. Compared to 3YSZ, 1.5Y-1350 exhibits superior biaxial flexural strength and reliability before LTD. Additionally, both 1.5Y-1250 and 1.5Y-1350 demonstrate higher fracture toughness than 3YSZ. Cell proliferation, differentiation, and mineralization were similar between 1.5YSZ and 3YSZ, with both producing mineralized nodules after 28 days.
1.5YSZ, sintered at lower temperatures, exhibited superior mechanical properties with comparable osteogenic capacity to 3YSZ, indicating its potential for dental implant applications.
[References]
1) Liu HY, Inokoshi M, Nozaki K. et al. Influence of high-speed sintering protocols on translucency, mechanical properties, microstructure, crystallography, and low-temperature degradation of highly translucent zirconia. Dent Mater 2022; 38:451-8.
2) Wu HZ, Ueno T, Nozaki K. et al. Lithium-Modified TiO2 Surface by Anodization for Enhanced Protein Adsorption and Cell Adhesion. ACS Appl Mater Interfaces 2023; 15: 55232-3.
This study investigated the mechanical properties of 1.5 mol% yttria-stabilized tetragonal zirconia (1.5YSZ) after sandblast and acid etch (SLA) treatment and aging and assessed its early osteogenic potential for dental implant applications.
[Method]
3YSZ (TZ-3YSB-E, Tosoh Corp., Tokyo, Japan) was sintered at 1500°C, while 1.5YSZ (Zgaia 1.5Y-HT, Tosoh Corp.) was sintered at 1250-1400°C. Surface modification involved alumina particle sandblasting and 40% hydrofluoric acid (HF) etching. Aging was simulated by exposure to 134°C for a duration of 50 hours. Characterization included scanning electron microscopy (SEM), 3D laser microscopy, wettability analysis, and X-ray diffraction (XRD) to assess low-temperature degradation (LTD) resistance. Mechanical properties were tested for biaxial flexural strength and fracture toughness (single-edge precracked beam method). MC3T3-E1 cells were used to evaluate proliferation, differentiation, and mineralization.
[Results and Discussion]
Higher sintering temperatures increased grain size and SLA treatment created nanoscale surface features. SLA also increased monoclinic phase content, but 1.5Y-1250 showed minimal monoclinic fraction during LTD. Aging increased the monoclinic phase content in all groups but did not affect surface roughness. SLA modification generated a super hydrophilic surface of all groups with no significant differences. Compared to 3YSZ, 1.5Y-1350 exhibits superior biaxial flexural strength and reliability before LTD. Additionally, both 1.5Y-1250 and 1.5Y-1350 demonstrate higher fracture toughness than 3YSZ. Cell proliferation, differentiation, and mineralization were similar between 1.5YSZ and 3YSZ, with both producing mineralized nodules after 28 days.
1.5YSZ, sintered at lower temperatures, exhibited superior mechanical properties with comparable osteogenic capacity to 3YSZ, indicating its potential for dental implant applications.
[References]
1) Liu HY, Inokoshi M, Nozaki K. et al. Influence of high-speed sintering protocols on translucency, mechanical properties, microstructure, crystallography, and low-temperature degradation of highly translucent zirconia. Dent Mater 2022; 38:451-8.
2) Wu HZ, Ueno T, Nozaki K. et al. Lithium-Modified TiO2 Surface by Anodization for Enhanced Protein Adsorption and Cell Adhesion. ACS Appl Mater Interfaces 2023; 15: 55232-3.
