Detection of Early Dental Caries Using Laser Induced Fluorescence with Back-Scattering Enhancement
Abstract —Dental caries is the infectious oral disease affecting people worldwide. Early dental caries detection helps to prevent caries progression by non-surgical methods and promote tooth remineralization. A simple method based on laser induced fluorescence spectrum with backscattered enhancement is proposed for the detection of initial caries on vitro teeth. Fluorescence spectra of carious erosion on different status were given. The radiation of backscattering, reflection and auto- fluorescence from teeth was registered simultaneously. By the analysis the characteristics of auto-fluorescence and anti-stokes fluorescence, both chemical variations and structural and morphological alterations can be evaluated. After the intensity of
fluorescence and backscattering light is normalized by the intensity of the reflection radiation, a measurable diagnostic criterion for various stages of carious lesion is put forward. For proving this opinion, contrastive study was given in healthy tooth, factitial caries, dental calculus and healthy enamel with surface breakdown. Preliminary results reveal that this new method has a high potential use to diagnose different levels of carious teeth and is reliable to the detection incipient carious erosion, calculus and filling teeth.
Keywords-dental caries; dental laser tips; laser induced fluorescence; backscattering light; detection
I. I NTRODUCTION Dental caries has high incidence and seriously damages people’s health, which is a kind of oral disease aroused by bacterial infection. It is a major aim in the preventive dentistry to prevent demineralization caused by carious teeth and promote remineralization of initial caries. But when the caries is only detected at an incipient stage, such aim could be reached. Investigation on diagnostic techniques of early caries has huge actual importance and commercial application. Traditional caries diagnostic methods like dental explorer or visual inspection can only find caries in moderate or cavitated stage which is irreversible and can be treated just by filling. Dental radiographs can only find the carious erosions which are very serious and have more than one third of the depth of tooth enamel. These conventional methods are not adequate to detect initial caries for their poor specificity and sensitivity. Furthermore, the pattern of dental caries has changed dramatically now because that the fluoride is added to the drinking water and the fluoride toothpastes are widely used. These new damage is found almost in the occlusal sunken surface, the adjacent touch places between teeth and cracks of posterior dentition ˈ that are difficult to examine. Therefore more sensitive and reliable diagnosis techniques are required to detect early non-cavitated caries and monitor its decay process . Over the past decades, many efforts have been made to develop optical methods for&@L�