Ozdemir Ali Kemal, Ozdemir Dogan Derya, Tugut Faik, Demir Hakan, Akin Hakan
Department of Prosthodontics, Faculty of Dentistry,Trakya University, Edirne,Turkey.
Department of Prosthodontics, Faculty of Dentistry,Cumhuriyet University, Sivas,Turkey.
Eur Oral Res. 2021 Jan 4;55(1):45-53. doi: 10.26650/eor.20210132.
The objective of this study was to determine whether the addition of different types of boron (Borax, Boric Acid and Colemanite) to polymethyl methacrylate denture base resin would improve flexural and impact strengths, and surface hardness of polymethyl methacrylate.
Borax, Boric acid, Colemanite were added to heat polymerized polymethyl methacrylate specimens were prepared for flexural strength (65x10x2.5 mm), impact strength (50x6x4 mm), and hardness (20x6x4 mm) tests according to the manufacturers' instructions (n=10). To determine flexural strength of the specimens, they were loaded until failure on a universal testing machine using a three point bending test. Specimens were subjected to the Charpy impact test machine. Hardness of the specimens was measured with an analog shoremeter Shore D. The data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (α=0.05).
The highest mean flexural strength value was seen in 3% Borax group and followed by 1% Colemanite group. In addition, the highest mean impact strength value was recorded in 1% Colemanite group, and differences between 1% Colemanite group and control group were found to be statistically significant (p=0,001). Furthermore, there was significant difference in hardness between control group and all other groups (p<0.001).
The addition of 1% Colemanite to polymethyl methacrylate improved the mechanical properties of PMMA.
本研究的目的是确定向聚甲基丙烯酸甲酯义齿基托树脂中添加不同类型的硼（硼砂、硼酸和硬硼钙石）是否会提高聚甲基丙烯酸甲酯的弯曲强度、冲击强度和表面硬度。
将硼砂、硼酸、硬硼钙石添加到热聚合的聚甲基丙烯酸甲酯中，根据制造商的说明制备用于弯曲强度（65×10×2.5mm）、冲击强度（50×6×4mm）和硬度（20×6×4mm）测试的试样（n = 10）。为了确定试样的弯曲强度，在万能试验机上使用三点弯曲试验对其加载直至破坏。试样在夏比冲击试验机上进行测试。用模拟邵氏硬度计邵氏D测量试样的硬度。数据采用Kruskal-Wallis和Mann-Whitney U检验进行分析（α = 0.05）。
在3%硼砂组中观察到最高的平均弯曲强度值，其次是1%硬硼钙石组。此外，在1%硬硼钙石组中记录到最高的平均冲击强度值，并且发现1%硬硼钙石组与对照组之间的差异具有统计学意义（p = 0.001）。此外，对照组与所有其他组之间的硬度存在显著差异（p < 0.001）。
向聚甲基丙烯酸甲酯中添加1%硬硼钙石可改善聚甲基丙烯酸甲酯的机械性能。
