人牙釉质中自由基含量与照射剂量的关系

RELATIONSHIP BETWEEN FREE RADICAL CONTENT IN HUMAN TOOTH ENAMEL AND RADIATION DOSE

本文用电子自旋共振（ＥＳＲ）技术，对２５个成人牙釉质样品中的自由基含量进行了测定，研究了牙釉质中自由基含量与辐射剂量的关系。在２５个成人牙样中，１６个男性样品，９个女性样品，年龄范围为１８～４１岁；样品分为５组，用６０Ｃｏγ射线照射各组样品，剂量率为０．４８Ｇｙ／ｍｉｎ，累积剂量分别为０．３０、０．５０、１．００、３．００和５．００Ｇｙ。实验结果指出，成人牙釉质样品的ＥＳＲ本底信号强度在男女两性之间差异不显著；在上述剂量范围内牙釉质中的自由基含量随所受剂量的增加而线性增加。当发生辐射事故后，在事故受照者牙釉质的ＥＳＲ测试条件与本文剂量效应刻度曲线的条件相一致的情况下，可利用本文研究结果估算受照剂量。

The free radical content of 25 adult tooth enamel samples were measured by electron spin resonance (ESR) technique, and the relationship between the free radical content of tooth enamel and radiation dose was investigated. Among the 25 adult enamel samples,there are 16 male and 9 female samples. Ages of tooth donors range from 18～41 years. 25 samples were divided into 5 dose groups, and irradiated with 60 Co γ ray at dose rate of 0.48 Gy/min. Radiation doses of 5 groups were 0.30, 0.50, 1.00, 3.00 and 5.00 Gy, respectively. No significant difference in background ESR signal intensity between male and female samples was observed; the free radical content in tooth enamel increases linearly with increasing of radiation dose. In the case of radiation accident, the results obtained could be applied to dose estimation when conditions of ESR measurement of exposed individual tooth enamel are similar to measurement conditions of dose response calibration curve in this paper. (