IN-VIVO DIAGNOSIS OF FISSURE CARIES USING A NEW ELECTRICAL-RESISTANCEMONITOR

The aim of this investigation was to study the accuracy of a newly dev eloped electrical resistance monitor in diagnosing occlusal fissure ca ries in vivo in teeth without cavitation. The electrical resistance wa s measured in vivo on human third molars without existing restorations and without any macroscopic carious cavitation. Data from 41 sites on 26 occlusal surfaces were obtained. After measurement, the teeth were extracted, histologically prepared, and serially sectioned perpendicu lar to the occlusal surface and examined for the presence of caries. N ineteen sites had no caries, 7 had enamel caries, and 15 sites showed dentinal caries, 4 of which deep dentinal caries. For the diagnosis of occlusal caries with the electrical resistance monitor, the specifici ty was 0.77, the sensitivity 0.93, and the accuracy 0.83. Likelihood r atios for four diagnostic levels (no caries, enamel caries, dentinal c aries, and deep dentinal caries) were 0.09, 0, 3.47, and 4.16, respect ively. Diagnosis of occlusal caries using conventional bite-wing radio graphs showed a specificity of 0.77, a sensitivity of 0.62, and an acc uracy of 0.71. The electrical resistance monitor was well suited to de tect in vivo occlusal caries under clinically intact fissures. The rat her high value (0.23) of false-positive ratings, however, might lead t o a substantial number of sound teeth being restored unnecessarily. Su bstantial improvement of occlusal caries diagnosis may be achieved by combining this method with others.