Fluorescence-aided Composite Removal in Directly Restored Permanent Posterior Teeth

Aim: The aim of this study was to quantitatively compare conventional composite removal and composite removal supported by the fluorescence-aided identification technique (FIT) regarding the completeness, selectivity, and duration of the procedure in directly restored permanent posterior teeth. Methods and Materials: Two operators removed standardized direct class II composite restorations (n=32 per operator) in human tooth models under simulated clinical conditions. According to a randomized allocation scheme, removal was performed with either the conventional technique (contra-angle handpiece) or supported by FIT. The duration of each removal procedure was recorded. The completeness and selectivity were volumetrically assessed through superimposition of three-dimensional surface scans. Statistical significance was tested by examining the overlap of 95% confidence intervals (CI). Multiple comparison was performed with Tukey tests for each variable. Results: Compared with the conventional technique, composite removal with FIT was faster (329 seconds [95% confidence interval (CI): 268390 seconds] vs 179 seconds [95% CI: 150-208 seconds]), generated less tooth substance loss (4.53 mm(3) [95% CI: 3.77-5.30 mm(3)] vs 2.77 mm(3) [95% CI: 2.11-3.43 mm(3)]), and left behind less composite residue (1.58 mm(3) [95% CI: 1.23-1.94 mm(3)] vs 0.53 mm(3) [95% CI: 0.39-0.67 mm(3)]). Conclusion: Within the limitations of this in vitro study, FIT facilitated the selective and expeditious removal of tooth-colored composites in directly restored posterior teeth.