Senior Consultant, Prosthodontic Specialist Clinic, Public Dental Service, Västerbotten, Umeå, Sweden.
Research Associate, Department of Odontology, Faculty of Medicine, Umeå University, Umeå, Sweden; and Private practice, Umeå, Sweden.
J Prosthet Dent. 2024 May;131(5):934.e1-934.e7. doi: 10.1016/j.prosdent.2024.02.010. Epub 2024 Mar 2.
Zirconium dioxide (zirconia) cannot be etched in a clinical setting, but zirconia restorations with minimal to no micromechanical bonding are approved and widely used in contemporary dentistry. However, information on the shear bond strength of zirconia and adhesive cement, on the effect of an added proportion of yttria, and on the effect of aging is lacking.
The purpose of this in vitro study was to evaluate the shear bond strength of cement luted to zirconia and the effect of aging.
A total of 131 test specimens were made from 4 zirconia materials with different amounts of yttria added to formulate yttria-partially stabilized zirconia (Y-PSZ); 3Y-PSZ (n=32), 4Y-PSZ (n=34), and 2 5Y-PSZs (n=32 and n=33). A dual-polymerizing cement and 10-methacryloyloxydecyl dihydrogen phosphate-containing primer were used. All specimens were stored in water at 37 °C, half of them for 24 hours and the other half for 6 months. After aging, the specimens were subjected to a shear bond strength test with a notched crosshead according to the International Organization for Standardization (ISO) 29022:2013 standard. The data were analyzed using the independent 2-sample t test, ANOVA, and the Levene test (α=.05).
The 3Y-PSZ material had higher mean ±standard deviation shear bond strength (31.83 ±12.80 MPa) compared with 4Y-PSZ (23.34 ±7.66 MPa) after 24 hours of aging in water and higher (28.98 ±14.03 MPa) than 4Y-PSZ (14.35 ±9.62 MPa) and one of the 5Y-PSZ (16.05 ±11.34 MPa) after 6 months. Debonding before loading occurred in all groups except for one of the 5Y-PSZ groups.
Zirconia without macromechanical retention, regardless of an added proportion of yttria, showed high shear bond strength, but the tested materials also had a high coefficient of variance, which, in practice, leads to the risk of the occasional debonding of zirconia restorations.
二氧化锆（氧化锆）在临床环境中无法被蚀刻，但具有最小至无微观机械结合的氧化锆修复体已被批准并广泛用于当代牙科。然而，关于氧化锆和黏结剂的剪切结合强度、添加氧化钇比例的影响以及老化的影响的信息尚缺乏。
本体外研究的目的是评估黏结剂黏结到氧化锆上的剪切结合强度和老化的影响。
用不同添加氧化钇比例的 4 种氧化锆材料（3Y-PSZ、4Y-PSZ 和 2 种 5Y-PSZ）共制作了 131 个试件；3Y-PSZ（n=32）、4Y-PSZ（n=34）和 2 种 5Y-PSZ（n=32 和 n=33）。使用了双固化黏结剂和含 10-甲丙烯酰氧癸基二氢磷酸酯的底漆。所有试件均在 37°C 水中储存，一半储存 24 小时，另一半储存 6 个月。老化后，根据国际标准化组织（ISO）29022：2013 标准，用带缺口的十字头对试件进行剪切结合强度测试。使用独立样本 t 检验、方差分析和 Levene 检验（α=.05）对数据进行分析。
在水中老化 24 小时后，3Y-PSZ 材料的平均剪切结合强度（31.83 ±12.80 MPa）高于 4Y-PSZ（23.34 ±7.66 MPa），在水中老化 6 个月后，3Y-PSZ 材料的平均剪切结合强度（28.98 ±14.03 MPa）高于 4Y-PSZ（14.35 ±9.62 MPa）和 1 种 5Y-PSZ（16.05 ±11.34 MPa）。除了 1 种 5Y-PSZ 组外，其余组在加载前均发生了脱粘。
无宏观机械固位的氧化锆，无论添加氧化钇的比例如何，均显示出高剪切结合强度，但测试材料的变异系数也较高，这在实际中会导致氧化锆修复体偶尔脱粘的风险。
