Arita Kenji, Lucas Milanita E, Nishino Mizuho
Department of Pediatric Dentistry, The University of Tokushima School of Dentistry, 3-18-15, Kuramoto, Tokushima 770-8504, Japan.
Dent Mater J. 2003 Jun;22(2):126-36. doi: 10.4012/dmj.22.126.
This present study investigated the effects of the addition of hydroxyapatite (HA) on the flexural strength and microstructure of conventional GIC, and its effect on the cement's initial flexural strength at different storage conditions. Specimens were fabricated by mixing HA in whisker or granule form into commercially prepared GIC, and these were subjected to a three-point bending test and SEM observations. Some specimens were stored in different conditions from dry to wet for 15 minutes to an hour prior to testing. When compared to the control, specimens with 16-25% HA whiskers added at P/L 1.75 showed a significant increase in the flexural strength (p < 0.05), and as well with 19% HA whiskers at P/L 1.75 (p < 0.001) and 2.33 (p < 0.05). A significant increase was also noted for those with 8-25% HA granules added at P/L's 1.75 (p < 0.05), 2.5 (p < 0.05) and 3.60 (p < 0.01). The addition of HA hastens the development of early (15 min, 1 hour) flexural strength of GIC in moist or wet conditions. These results indicate that the addition of HA, regardless of form, improve the flexural and microstructural properties of GIC.
本研究调查了添加羟基磷灰石（HA）对传统玻璃离子水门汀（GIC）弯曲强度和微观结构的影响，以及在不同储存条件下其对该水门汀初始弯曲强度的影响。通过将晶须状或颗粒状的HA混入市售的GIC中来制备样本，并对其进行三点弯曲试验和扫描电子显微镜观察。一些样本在测试前于从干燥到潮湿的不同条件下储存15分钟至1小时。与对照组相比，在粉液比（P/L）为1.75时添加16 - 25% HA晶须的样本弯曲强度显著增加（p < 0.05），在P/L为1.75（p < 0.001）和2.33（p < 0.05）时添加19% HA晶须的样本也是如此。在P/L为1.75（p < 0.05）、2.5（p < 0.05）和3.60（p < 0.01）时添加8 - 25% HA颗粒的样本也观察到显著增加。在潮湿或湿润条件下，添加HA可加速GIC早期（15分钟、1小时）弯曲强度的发展。这些结果表明，无论HA的形式如何，添加HA均可改善GIC的弯曲性能和微观结构性能。
