Summary. The technology advance in recent years determines the need of construction of modern appliances for early diagnosis of dental caries, which are categorized by great precision, non-invasiveness, easy usage and wide availability. Such non-invasive and accurate tool for diagnostics of caries is Caries Detector (LED), Bulgarian product by "Optica Laser". The detector emits a specifi c wavelength of near ultraviolet light, which causes fl uorescence to porphyrins -metabolic products of the life cycle of caries-inducing bacteria. The purpose of the study is piloting a new diagnostic tool for detection and monitoring of caries excavation based on fl uorescence -LED UV caries detector of company "Optica laser". Subjected to examination by caries indicator dye and UV caries detector were sixty permanent teeth with deep dentine caries. Two methods were used to assess the dentin caries -UV fl uorescence detector of "Optica Laser" and staining with caries indicator -dye (Sable ™ Seek®). It was found that among all sixty teeth, the fi elds, closed by margins of carious process overlap. Fifty-four of tested teeth has shown bigger fi eld of images with staining method and six -smaller in comparison to the fl uorescent method. Ultraviolet fl uorescence caries detector of "Optica Laser" company is affordable and easy applicable method for controlled excavation of dentine caries. The detector can be used in daily dental practice equally with other methods. The unit has a number of advantages -non-invasiveness, lack of interaction with tooth structures, speed, reliability, effi ciency, predictability and repeatability of results.