电子顺磁共振测量犬牙不确定性研究

目的:探索使用转角器自动转动、随机手动转动、随机晃动样品和使用内标物(Marker)对犬牙电子顺磁共振(EPR)测量不确定性的影响,为辐射吸收剂量估算提供依据.方法:取3颗3岁家养犬牙为样品,通过化学手段获取犬牙牙釉质,使用EPR波谱仪检测其对方向的依赖情况,以及转角器自动转动、随机手动转动和随机晃动3种方式对犬牙EP...

Study on the uncertainty of EPR in measuring canine tooth

Objective:To explore the influences of automatic rotation by using goniometer,randomly manual rotation,random shaking sample and using internal marker on the uncertainty of electron paramagnetic resonance(EPR)measurement for canine tooth so as to provide basis for the estimation of radiation absorbed dose.Methods:In this experiment,the enamels of 3 canine teeth of dog aged 3-year-old were obtained by chemical mean,and then the EPR spectrometer was used to detect the dependence of them on direction,as well as the effects of three means(automatic rotation of goniometer,random manual rotation and random shaking)on EPR measurement values and Q value of canine teeth.The mutual effect between the internal Marker and the sample of canine teeth was observed and analyzed.And the change of EPR signal intensities of the canine teeth with or without internal Marker were further compared.Results:The differences of the measurement results of random manual rotation and random shaking among different rotation angle and among different shaking times were not significant.And in the mean of using goniometer for rotation,the differences of HPP(RIS)and HP-P(RIS)/HP-P(Marker)among different angles under Marker condition and the difference of HP-P(RIS)results among different angles without Marker condition were significant(F=4.276,F=4.26,F=26.977,P<0.05).For the coefficient of dispersion of the measurement results,the goniometer was the smallest,and the random manual rotation was the second,and the random shaking was the last.When the samples occurred physical changes or chemical changes,the EPR measurement value of the internal Marker also changes accordingly.The difference of the measurement results with internal Marker between the immobility and the picking and replacement of sample on primary place was no significant,while that without internal Marker between them was significant(t=7.063,P<0.05).Conclusion:Random manual rotation and the use of internal Marker can reduce the uncertainty of measuring canine tooth and improve the quality of detection.