Measurement of Fluoride Distribution in Teeth

研究抑制龋病的最佳氟浓度可能是了解氟化物在耐酸层等微域分布的关键步骤之一。可采用PIGE、EPMA、SIMS等方法。在这里，微光束PIGE被用于获得高的位置分辨率。由日本高崎工业研究所（JAERI Takasaki） TIARA单端加速器加速的1.7 MeV质子束被送入微束装置。光束光斑尺寸约为1μm，光束电流约为100pA。用核反应^<19>F(p, A γ)^<16 >o测量氟密度。该反应的伽马射线用2”BGO探测器检测。质子诱导x射线用硅（锂）探测器测量钙密度。用铜箔的x射线产率监测光束强度，进行定量分析。测定了蚀牙和未蚀牙的氟分布。在TIARA上，亚微米束线可以看到狭窄区域内观察到的氟浓度。它可能会为牙科提供一种新工具。

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.