本文基于牙菌斑与牙齿组织自体荧光光谱的差异性, 提出了一种利用自体荧光成像的牙菌斑量化分析方法。首先测试了牙齿样品在 405 nm激发光作用下自体荧光光谱分布, 在分析荧光颜色参量与牙菌斑含量相关性的基础上, 提出以荧光图像的 R/B作为牙菌斑含量量化的参量, 并确定使用中心波长为 490 nm的长波通滤光片对荧光光谱波段进行选择性提取。最后, 搭建实验装置获取了牙齿自体荧光图像, 利用 R/B值作为分割阈值得到了三个不同等级的牙菌斑含量与分布的量化分析结果, 与视诊结果相符。

Based on the differences between auto-fluorescence spectra of plaque and dental tissue, a quantitative analysis method of plaque using auto-fluorescence imaging was presented. Auto-fluorescence spectrum of tooth samples excited by 405 nm was measured, on the basis of analyzing the correlation between color parameters of fluorescence and dental plaque content, R/B of fluorescence image was proposed as quantitative assessment parameter of dental plaque content, meanwhile long-wavelength pass filter with central wavelength of 490 nm was used to filter fluorescence spectral bands. Finally, experimental setup was built to obtain the auto-fluorescence image. Quantitative analysis results of three different levels of plaque content and distribution was obtained by using R/B value as segmentation thresholds, which confirmed with visual examination results.