Universidade Estadual Paulista (UNESP), Faculdade de Odontologia de Araraquara, Departamento de Materiais Odontológicos e Prótese, Araraquara, SP, Brasil.
Universidade Estadual Paulista (UNESP), Faculdade de Odontologia de Araraquara, Departamento de Odontologia Social, Araraquara, SP, Brasil.
J Appl Oral Sci. 2022 Apr 29;30:e20210536. doi: 10.1590/1678-7757-2021-0536. eCollection 2022.
The purpose of this study is to evaluate, over a simulated 5-year period, the effect of simulated gastric juice alternated with brushing on CAD-CAM monolithic materials considering microhardness, substance loss, flexural strength, and reliability of the materials.
Blocks from Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), IPS e.max CAD (EMAX), and Vita Suprinity (VS) were milled into cylinders and sliced into disks. The EMAX and VS were crystallized, and all specimens were polished with silicon carbide papers and allocated as follows: 1) artificial saliva + brushing or 2) simulated gastric juice (0.113% hydrochloric acid (HCl) solution in deionized water, pH 1.2) + brushing, simulating 1, 3, and 5 years of clinical function. Each year of clinical function was simulated by three repetitions of immersion for 3 hours in artificial saliva or simulated gastric juice followed by 1,217 brushing cycles. The microhardness and substance loss were evaluated at baseline (T0) and at each year by using a Vickers hardness tester and an analytical balance. The biaxial flexural strength (BFS) test was performed in a mechanical testing machine at the end of the 5th year. Weibull modulus was calculated from the BFS data.
The microhardness of the LU was not influenced by the treatment, whereas that of the other materials, in certain years, was significantly lower in the gastric juice + brushing groups in comparison with artificial saliva + brushing groups. In general, the materials did not present a significant change in microhardness over time, for either of the treatments. The LU alone showed greater substance loss in the gastric juice + brushing groups for every year. In both treatments, the LU, VE, and EMP exhibited a significant increase in the substance loss over time. The treatment did not affect the BFS of the materials. The gastric juice + brushing decreased the reliability of the VE.
All materials were somehow impaired by the gastric juice + brushing in at least one of the evaluated parameters, except for the BFS. However, in a deeper analysis, the LU would be the least indicated materials, followed by VE, for patients with eating disorders.
本研究旨在模拟 5 年时间，评估模拟胃液与刷洗交替作用对 CAD-CAM 整体材料的影响，考察材料的显微硬度、物质损失、弯曲强度和可靠性。
将 Lava Ultimate（LU）、Vita Enamic（VE）、IPS Empress CAD（EMP）、IPS e.max CAD（EMAX）和 Vita Suprinity（VS）的块状物加工成圆柱体并切成圆盘。EMAX 和 VS 进行了结晶处理，所有样本均用碳化硅砂纸进行抛光，并分为以下两组：1）人工唾液+刷洗或 2）模拟胃液（去离子水中 0.113%盐酸（HCl），pH 值 1.2）+刷洗，模拟 1、3 和 5 年的临床功能。每年的临床功能通过将样本在人工唾液或模拟胃液中浸泡 3 小时，重复 3 次，然后进行 1,217 次刷洗循环来模拟。在基线（T0）和每年通过维氏硬度计和分析天平评估显微硬度和物质损失。在第 5 年末，在机械试验机上进行双轴弯曲强度（BFS）测试。从 BFS 数据中计算韦布尔模数。
LU 的显微硬度不受处理影响，而其他材料在某些年份中，在胃液+刷洗组中显著低于人工唾液+刷洗组。一般来说，无论采用哪种处理方式，材料的显微硬度在整个 5 年内都没有明显变化。单独使用 LU 时，在胃液+刷洗组中，每年的物质损失都更大。在两种处理方式中，LU、VE 和 EMP 的物质损失都随时间的推移而显著增加。处理方式不影响材料的 BFS。胃液+刷洗降低了 VE 的可靠性。
除 BFS 外，至少有一种评估参数的胃液+刷洗会使所有材料受损。然而，在更深入的分析中，对于有饮食失调的患者，LU 将是最不适合的材料，其次是 VE。
