The fluorescence of resin-based composites: An analysis after ten years of aging

The long-term preservation of fluorescence qualities of resin-based composite (RBC) restorations is an absolute condition for the implementation of the fluorescence-aided identification technique (FIT) in dentistry and forensic medicine. Therefore, this study assessed the fluorescence of 244 color shades of 16 commercially available RBC brands with a monochromator-based multimode microplate reader. The specimens were stored in the dark at room temperature and reassessed ten years after the initial investigation. The mean intensity of the fluorescence maxima decreased from (31,030±936) RFU to (22,027±632) RFU. Linear regression resulted in r²=0.972 and a slope=0.701±0.005. The fluorescence intensity of the tested RBCs dropped to about 70% of the initial intensity independent of the brand, color shade and initial fluorescence intensity. On the basis of this in vitro 10-year data set, we assume that in vivo RBC fluorescence is also suitable for the detection and differentiation of clinically aged RBC restorations by FIT.