Direct Spectrometry: A New Alternative for Measuring the Fluorescence of Composite Resins and Dental Tissues

Abstract

The aim of this study was to evaluate the fluorescence intensity of different composite resins and compare those values with the fluorescence intensity of dental tissues. Different composite resins were used to make 10 discs (2 mm in depth and 4 mm in diameter) of each brand, divided into groups: 1) Z (Filtek Z350, 3M ESPE), 2) ES (Esthet-X, Dentsply), 3) A (Amelogen Plus, Ultradent), 4) DVS (Durafill-VS, Heraeus Kulzer) with 2 mm composite resin for enamel (A2), 5) OES ([Esthet-X] opaque-OA [1 mm] + enamel-A2 [1 mm]); 6) ODVSI ([Charisma-Opal/Durafill-VSI], opaque-OM (1 mm) + translucent [1mm]), and 7) DVSI ([Durafill- VSI] translucent [2 mm]). Dental tissue specimens were obtained from human anterior teeth cut in a mesiodistal direction to obtain enamel, dentin, and enamel/dentin samples (2 mm). The fluorescence intensity of specimens was directly measured using an optic fiber associated with a spectrometer (Ocean Optics USB 4000) and recorded in graphic form (Origin 8.0 program). Data were submitted to statistical analysis using Dunnet, Tukey, and Kruskall-Wallis tests. Light absorption of the composite resins was obtained in a spectral range from 250 to 450 nm, and that of dental tissues was between 250 and 300 nm. All composite resins were excited at 398 nm and exhibited maximum emissions of around 485 nm. Fluorescence intensity values for all of the resins showed statistically significant differences (measured in arbitrary units [AUs]), with the exception of groups Z and DVS. Group DVSI had the highest fluorescence intensity values (13539 AU), followed by ODVS (10440 AU), DVS (10146 AU), ES (3946 AU), OES (3841 AU), A (3540 AU), and Z (1146 AU). The fluorescence intensity values for the composite resins differed statistically from those of dental tissues (E=1380 AU; D=6262 AU; E/D=3251 AU). The opacity interfered with fluorescence intensity, and group Z demonstrated fluorescence intensity values closest to that of tooth enamel. It is concluded that the fluorescence intensity values were significantly different among the composite resins and compared with dental tissues. The direct spectrofluorimetric method represents a tool for evaluating the fluorescence of composite resins.

Staining Beverages and Cigarette Smoke on Composite Resin and Human Tooth Fluorescence by Direct Spectrometry

“…The results showed that the CR Filtek Z350 obtained FI means closest to those of tooth, corroborating previous studies. 8,23 Esthet-X, Amelogen Plus, and Durafill VS showed higher intensity values than those of tooth, as observed by da Silva et al 23 It may be related to differences in fluorophore within the composition of each CR, trade secret not disclosed by the manufacturers. The differences in fluorescence values could be related to the difference in type of particles as well as resin matrix.…”

“…24 However, little is known about the fluorophore agents present in the CRs, because it is a trade secret. 23,24 There is no fluorescence pattern to be followed, comparatively to which happen with the color scales. Most manufacturers follow the VITA color scale (A, B, C, and D).…”

“…The optical fiber spectrometer enables the direct position over the tooth, contributing for the best esthetics results of restorations. 23 In addition, there are reports in the literature that the surface and subsurface layer of a stratified restoration in different types of CRs would present different FI. 23 To avoid this bias, the fluorescence of the CRs was evaluated in this study using a standard shade -A2, specified as enamel composites to compare with the tooth substrate.…”

“…23 In addition, there are reports in the literature that the surface and subsurface layer of a stratified restoration in different types of CRs would present different FI. 23 To avoid this bias, the fluorescence of the CRs was evaluated in this study using a standard shade -A2, specified as enamel composites to compare with the tooth substrate. The action of cigarette smoke and staining beverages promoted differences of FI among different CRs and that of tooth, rejecting the null hypothesis of this study.…”

“…The FI values were located in the visible light spectrum between 450 and 700 nm. 23 The initial fluorescence of CRs and tooth specimens was recorded directly on the surface at 24 hours after the polishing. The final fluorescence was recorded after the treatment with dye substances (cigarette smoke, coffee solution, and cola-based soft drink).…”