Caries detection methods: Can they aid decision making for invasive sealant treatment?

The decision to place sealants is a difficult one, and it has been suggeste d that in a low risk population it may be efficient to wait until caries is detected in the fissure. An invasive sealant technique with fissure prepar ation may then be indicated. The diagnostic method used in the indication o f such a procedure should accurately detect both dentine caries and sound f issures: high sensitivity for dentine caries (at D3 threshold) with high sp ecificity for enamel caries (at D1 threshold), The aims of this study were to assess the diagnostic performance of selected diagnostic methods at norm al cut-offs for traditional dentine caries detection and at reduced cut-off s in relation to the desired performance mentioned above, and to assess whe ther fissure opening allows for accurate visual detection of dentinal carie s, Data were obtained from 230 occlusal sites of 101 extracted human molar teeth, Diagnostic methods used on the entire sample were: visual inspection , electrical conductance measurements and laser fluorescence measurements. The sample was then divided into two groups, Group 1 was subjected to visua l inspection after application of a dye. Group 2 was subjected to visual in spection after fissure opening only, and after subsequent dye application. Validation was performed by histological investigation. The results with cu t-offs normally used in dentine caries detection were roughly in accordance with the literature, except for laser fluorescence, The sensitivity of vis ual inspection for dentinal caries (D3) was 17% before and 70% after fissur e opening. Using reduced cut-offs, a 100% sensitivity (D3) was achieved wit h 2 methods, but this also resulted in 63 or 87% false positive diagnoses o f sound surfaces. Visual inspection and electrical methods both showed a mo derate to high sensitivity (D3) with a higher than 50% specificity (D1). It was concluded that visual inspection and electrical methods at reduced cut offs may aid the indication of invasive sealant treatment. The visual detec tion of dentinal caries is substantially increased, but not perfect after f issure opening. Copyright (C) 2001 S. Karger AG. Basel.