Accurate dental restorations require die materials with optimal surface hardness. This study evaluated drying method effects on three Type IV dental stones: Elite Rock (ZERMACK), Fuji Rock (GC), and Kal Rock (KALROCK). One hundred twenty samples of ZERMACK, GC, and KALROCK were prepared using manufacturer-recommended water/powder ratios. Samples were divided into four subgroups based on drying method: 1-hour air drying, 24-hour air drying, 1-hour air drying followed by 10 min of microwave drying at low power, and 24-hour air drying followed by die hardener application. Knoop hardness testing was conducted according to ADA specification #25. One-way ANOVA and pairwise comparisons were used for statistical analysis. GC showed the highest mean hardness (84.58), followed by ZERMACK (74.82), and KALROCK (67.07). Significant differences existed (F [2, 27] =190.463, P < .001). GC had significantly higher hardness than KALROCK (17.52 difference) and ZERMACK (9.76 difference) after 24 hours. GC exhibited superior surface hardness. Material selection and drying methods significantly impact Type IV gypsum hardness for dental dies.

Keywords: Dental stone; die materials; drying methods; surface hardness; type IV gypsum.

Copyright: © 2025 Journal of Pharmacy and Bioallied Sciences.

准确的牙科修复要求使用具有最佳表面硬度的模型材料。本研究评估了三种Type IV牙科石膏（Elite Rock、Fuji Rock和Kal Rock）在不同干燥方法下的影响。根据制造商推荐的水粉比例，制备了120个ZERMACK、GC和KALROCK样本，并依据干燥方式将其分为四个子组：1小时空气干燥、24小时空气干燥、先进行1小时空气干燥再以低功率微波干燥10分钟以及24小时空气干燥后再使用模型硬化剂。根据ADA规范#25进行努氏硬度测试，采用单因素方差分析和成对比较法进行统计学分析。结果显示，GC的平均硬度最高（84.58），其次是ZERMACK（74.82）和KALROCK（67.07）。差异显著（F [2, 27] =190.463，P < .001）。在24小时干燥后，GC的硬度比KALROCK高17.52，并且比ZERMACK高9.76。结果表明，GC表现出优异的表面硬度。材料选择和干燥方法显著影响Type IV石膏模型的硬度。

关键词：牙科石膏；模型材料；干燥方法；表面硬度；Type IV石膏。