Measurement of Fluoride Distribution in Teeth

研究抑制龋病的最佳氟化物浓度可能是了解氟化物在耐酸层等微观区域中分布的关键步骤之一。方法：采用PEGE、EPMA、SIMS等方法。在这里，微束PIGE被用来获得高位置分辨率。由JAERI Takasaki的Tiara单端加速器加速的1.7 MeV质子束被送到微束设施中。束斑尺寸约为1μm，束流约为100pA。用核反应测量氟密度。用2“BGO探测器探测这一反应的伽马射线，用Si(Li)探测器探测质子诱导的X射线，测量钙密度，用铜箔的X射线产额监测束流强度进行定量分析，测量酸蚀和未酸蚀牙齿的氟分布。用TIARA的亚微米束线可以观察到狭窄区域的氟浓度。这可能为牙科提供一种新的工具。

Investigating the optimum fluoride concentration for the inhibition of caries may be one of key steps to know the fluoride distribution in such a micro domain as acid-resistant layer. Methods as PIGE, EPMA and SIMS can be used. Here the micro-beam PIGE was applied to obtain high position resolution.The 1.7 MeV proton beam accelerated by the TIARA single-ended accelerator at JAERI Takasaki was delivered to a micro-beam facility. The beam spot size was about 1μm with a beam current of about 100pA.A nuclear reaction ^<19>F(p, aγ)^<16>O was used for measuring fluorine density. Gamma rays of this reaction were detected with a 2" BGO detector. Proton induced X-rays were detected with a Si(Li) detector for measuring calcium density. Beam intensity was monitored with X-ray yield from a copper foil for quantitative analysis. The fluorine distribution was measured for etched and non-etched teeth. Observed fluorine concentration in the narrow area can be seen with sub-micron beam line at TIARA.It might contribute a new tool in dentistry.