The aim of this study was to assess whether preventive fissure sealants could be differentiated from sealant restorations. The problem of being unable to differentiate between these two tooth states has implications for practitioners and epidemiologists (Davies, 1990). One hundred and seventeen permanent molar teeth, all sealed with a clear sealant, were examined under two types of conditions. These were the Daray 'Versatile light'; mirror, wet teeth, and the Daray 'Operating light 2'; mirror, dry teeth. The subjects' records were subsequently consulted to provide the validating criteria. The results suggest that in a dental hospital environment, when a clear sealant material is in place, it is possible to differentiate between preventive fissure sealants and sealant restorations. It would seem, however, that the 'sealant-alone' variety of sealant restoration was the one most often mistaken for a preventive fissure sealant. The different examination conditions did not markedly affect the examiners' ability to differentiate between the two tooth stage.