The fluorescence spectra of healthy teeth and dental calculus are collected under the excitation of a 405 nm LED,respectively.The spectra have broad bands and contiguous peaks are overlapped,which brings difficulties for analysis.The spectra are further analyzed and compared by using curve-fitting Gaussian Function.Six possible detection methods are proposed,and their sensitivities are compared.The detection results show that the best sensitivity is observed by using the ratio of the fluorescence intensity ...