Children and adolescents must be examined often for occlusal caries. Diagno
sis of fissure caries is difficult especially when the tooth surface appear
s seemingly intact. It has been shown that using traditional clinical metho
ds, as little as 20% of teeth with fissure caries under intact surfaces wer
e correctly recognised as such. Therefore, new methods for increasing the a
ccuracy of diagnosis have been sought for years. Recently, a new device, ba
sed on fluorescence measurements, was introduced. The purpose of this study
was to test the device under in vivo conditions in order to provide recomm
endations for its use in the dental office. Seven general dental practition
ers examined a total of 332 occlusal surfaces in 240 patients. Caries exten
t was determined for each site after operative intervention (= 'gold standa
rd'). Clinical inspection and analysis of bitewing radiographs exhibited st
atistically significant lower sensitivities (31-63%) than did the DIAGNOden
t device (sensitivity greater than or equal to 92%). It is recommended that
the laser device is used in the decision-making process in relation to the
diagnosis of occlusal caries as a second opinion in cases of doubt after v
isual inspection.