Department of Dental Physical Sciences, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Francis Bancroft Building, Mile End, London E1 4NS, UK.
J Mater Sci Mater Med. 2010 Nov;21(11):2901-5. doi: 10.1007/s10856-010-4146-x. Epub 2010 Aug 18.
The set of glass ionomer cement (GIC) is accelerated by application of ultrasound. Although GIC has somewhat displaced zinc polycarboxylate cement (ZPC) in dental applications the latter is still extensively used. Like GIC, it provides direct adhesion to tooth and can provide F release, but is more radiopaque and biocompatible than GIC. The aim of this study is to examine the effect of ultrasound on the setting of ZPC using Fourier transform infra red spectroscopy and any interaction with SnF(2) addition. ZPC with and without SnF(2) addition (+/-S) at luting (L) 2:1 P/L ratio and restorative (R) 4:1 P/L ratio consistencies. Ultrasound is applied to the cement using Piezon-Master 400, EMS, Switzerland at 60 s from start of mixing for 15 s. The ratios of absorbance peak height at 1,400 cm(-1) -COO(-) to that at 1,630 cm(-1) -COOH were measured and compared those obtained for the cement not treated with US. These values were taken at the elapsed time at which no further change in spectrum [ratio] was observed at room temperature [10-20 min]. The US results are taken at 2 or 3 min. No US: R/+S (1.09), R/-S (1.2), L/+S (1.07), L/-S (1.04); US: R/+S (1.50), R/-S (1.64), L/+S (1.38), L/-S (1.05). The results show all four ZPC formulations are very sensitive to ultrasound whether with or without SnF(2). Reducing US to 10 s produces lower initial ratios but these increase up to 10 min when very high ratios (>2) are obtained. Previous studies with restorative GICs found that 40-55 s US was needed to produce the effect found with 15 s on ZPCs. ZPC powder is more basic than GIC glass; this may account for ZPC's greater sensitivity to US. Ultrasound may provide a useful adjunct to the clinical use of ZPC both as luting agent and temporary restorative.
玻璃离子水门汀（GIC）通过应用超声波加速凝固。虽然在牙科应用中，GIC 在某种程度上已经取代了锌聚羧酸酯水泥（ZPC），但后者仍被广泛使用。与 GIC 一样，它可以直接粘接到牙齿上，并可以提供氟释放，但比 GIC 更具有放射性和生物相容性。本研究旨在使用傅里叶变换红外光谱法研究超声波对 ZPC 凝固的影响，并研究其与 SnF(2)添加物的相互作用。ZPC 分别添加和不添加 SnF(2)(+/-S)，以 1:2 水/粉比例的黏固剂（L）和 1:4 水/粉比例的修复剂（R）进行实验。使用 Piezon-Master 400，EMS，瑞士的超声波在混合开始后 60 秒内，以 15 秒的间隔应用于水泥。测量在 1,400 cm(-1) -COO(-)吸收峰高度与在 1,630 cm(-1) -COOH 吸收峰高度的比值，并将其与未用 US 处理的水泥的测量值进行比较。这些值是在室温下（10-20 分钟）光谱[比值]不再发生变化的时间点上获得的。US 结果在 2 或 3 分钟时获得。未用 US：R/+S（1.09），R/-S（1.2），L/+S（1.07），L/-S（1.04）；用 US：R/+S（1.50），R/-S（1.64），L/+S（1.38），L/-S（1.05）。结果表明，无论是否添加 SnF(2)，四种 ZPC 配方都对超声非常敏感。将超声减少到 10 秒会产生较低的初始比值，但当获得非常高的比值（>2）时，这些比值会增加到 10 分钟。以前对修复性 GIC 的研究发现，40-55 秒的 US 即可产生与 ZPC 上 15 秒 US 相同的效果。ZPC 粉末比 GIC 玻璃更碱性；这可能解释了 ZPC 对 US 更敏感的原因。超声可以为 ZPC 的临床应用提供有用的辅助，无论是作为黏固剂还是临时修复剂。
