An Automated Digital Microradiography System for Assessing Tooth Demineralization

摘要

Digital Transverse microradiography (TMR) offers several advantages over film based methods including real-time image acquisition, excellent linearity with exposure, and it does not require expensive specialized film. The purpose of this work was to demonstrate that a high-resolution digital microradiography system can be used to measure the volume percent mineral loss for sound and demineralized enamel and dentin thin sections from 150-350-μm in thickness. A custom fabricated digital microradiography system with ～ 2-μm spatial resolution consisting of a digital x-ray imaging camera, a computerized high-speed motion control system and a high-intensity copper Kα x-ray source was used to determine the volume percent mineral content of sound and demineralized tooth sections. The volume percent mineral loss was compared with cross-sectional microhardness measurements on sound extracted human teeth. The correlation between microhardness and microradiography was excellent (Pr=0.99) for section thickness ranging from 59-319-μm (n=13). The attenuation was linear with varying exposure time from 1-10 seconds. Digital TMR is an effective and rapid method for the assessment of the mineral content of enamel and dentin thin sections.