Diagnostic accuracy of QrayPen fluorescence scoring for secondary caries in repair-/replacement-indicated posterior composite restorations
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Detection and Removal of Tooth-Colored Composite Resin Using the Fluorescence-Aided Identification Technique
Published on: July 27, 2022
Ahmad Bittar1, Elif Alkan2, Dilek Tağtekin2
1Department of Restorative Dentistry, Faculty of Dentistry, Istinye University, Istanbul, Türkiye, Turkey. ahmet.baytar989@gmail.com.
Objectives:
To evaluate the adjunctive diagnostic performance of QrayPen C fluorescence-image severity scoring (QS) for identifying same-site secondary caries in posterior composite restorations already selected for repair or replacement.
Materials And Methods:
In this single-centre prospectively conducted observational diagnostic-accuracy study, 102 patients were assessed; 14 declined participation and 5 were excluded because of non-interpretable QLF/clinical images. The final analysis included 83 adults and 120 repair-/replacement-indicated posterior composite restorations. Restorations were assessed using Nyvad criteria, bitewing ICCMS scoring, and QrayPen C imaging. QS was scored on a 0-3 scale and analysed at thresholds > 0, >1, and > 2. The reference standard was same-site dentin status after removal.
Results:
Secondary caries was confirmed in 80/120 restorations (66.7%). For QS > 0, sensitivity was 85.0%, specificity 90.0%, accuracy 86.7%, LR + 8.50, and LR- 0.17. Patient-level clustered bootstrap analysis gave similar but wider estimates: sensitivity 85.0% (clustered 95% CI 75.9-92.8) and specificity 90.0% (clustered 95% CI 80.0-97.7). Higher QS thresholds increased specificity but reduced sensitivity.
Conclusions:
In repair-/replacement-indicated restorations, QS > 0 may help localize suspicious areas and increase diagnostic confidence for same-site secondary caries, but the estimates apply to an enriched clinically problematic cohort.
Clinical Relevance:
QrayPen QS should be interpreted as an adjunctive imaging-derived signal. QS positivity should not justify replacement in isolation, and QS = 0 should not be interpreted as evidence of sound dentin.
