目的:牙科陶瓷由于热老化和暴露于酸性溶液而变质,改变其显微硬度和表面粗糙度。这项研究评估了几种计算机辅助设计和计算机辅助制造(CAD-CAM)修复牙科材料在暴露于酸性溶液和热老化后的表面粗糙度和显微硬度方面的抵抗力。
方法:五种不同的整体式CAD-CAM修复材料,两种白云母增强玻璃陶瓷(G-Ceram和CERECBlocs),氧化锆渗透的硅酸锂(CeltraDuo),树脂纳米陶瓷(Grandio),和整体式氧化锆(InCorisTZI),用于创建2毫米厚的矩形标本(n=100)。浸入酸性唾液(pH=4.0)(ST)或胃液(pH=1.2)(GT)后,每种材料都经历了10,000次热老化循环。在基线处评估样品的维氏显微硬度和平均表面粗糙度,热老化和暴露于胃液或酸性唾液后。使用原子力显微镜检查表面性质。使用带有Bonferroni校正的Mann-WhitneyU检验和Wilcoxon符号秩检验进行统计分析(a=0.05)。
结果:两种白云母增强的玻璃陶瓷(G-ceram和CEREC)的表面粗糙度随ST显着降低(p=0.027和p=0.044)。当比较老化方案时,只有CEREC受到影响,ST组粗糙度显著降低(p=0.009).除G-Ceram的ST亚组外,所有组的两种老化方案后的显微硬度值均显着降低。当比较衰老方案时,只有Coris受到影响,GT组显微硬度显著降低(p=0.002)。
结论:测试材料的表面粗糙度不受GT的影响。在ST阶段,只有白云母陶瓷的表面粗糙度降低。两种老化过程均使测试陶瓷的显微硬度显着降低。由于与其他CAD-CAM材料相比,它们的显微硬度和表面粗糙度变化值较低,因此,水镁石增强的玻璃陶瓷材料对于胃食管反流病患者和饮食中酸性食物含量高的患者可能是有利的。
OBJECTIVE: Dental ceramics deteriorate as a result of thermal aging and exposure to acidic solutions, which change their microhardness and surface roughness. This study assessed the resistance of several computer-aided design and computer-aided manufacturing (CAD-CAM) restorative dental materials in terms of surface roughness and microhardness following exposure to acidic solutions and thermal aging.
METHODS: Five different monolithic CAD-CAM restorative materials, two leucite-reinforced glass ceramics (G-Ceram and CEREC Blocs), a zirconia-infiltrated lithium silicate (Celtra Duo), a resin nanoceramic (Grandio), and monolithic zirconia (inCoris TZI), were used to create 2-mm-thick rectangular specimens (n = 100). After being immersed in either acidic saliva (pH = 4.0) (ST) or gastric juice (pH = 1.2) (GT), each material was subjected to 10,000 cycles of thermal aging. The Vickers microhardness and average surface roughness of the specimens were assessed at baseline, following thermal aging and exposure to either gastric juice or acidic saliva. The surface properties were examined using an atomic force microscope. The Mann‒Whitney U test with Bonferroni correction and the Wilcoxon signed-rank test was used for statistical analysis (a = 0.05).
RESULTS: The surface roughness of two leucite-reinforced glass ceramics (G-ceram and CEREC) significantly decreased with ST (p = 0.027 and p = 0.044). Only the CEREC was affected when the aging protocols were compared, and the ST group had a significant reduction in roughness (p = 0.009). The microhardness values significantly decreased after both aging protocols in all groups except for the ST subgroup of G-Ceram. Only inCoris was affected when the aging protocols were compared, and the GT group exhibited a significant reduction in microhardness (p = 0.002).
CONCLUSIONS: The surface roughness of the tested materials was not affected by the GT. Only leucite ceramics exhibited a decrease in surface roughness in the ST stage. Both aging processes produced a significant decrease in the microhardness of the tested ceramics. Leucite-reinforced glass-ceramic materials may be advantageous for patients with gastroesophageal reflux disease and those with a diet high in acidic foods due to their lower values for changes in microhardness and surface roughness compared to those of other CAD-CAM materials.