title: FT-Raman spectroscopy study of organic matrix degradation in nanofilled resin composite.
abstract: This in vitro study evaluated the effect of light curing unit (LCU) type, mouthwashes, and soft drink on chemical degradation of a nanofilled resin composite. Samples (80) were divided into eight groups: halogen LCU, HS--saliva (control); HPT--Pepsi Twist®; HLC--Listerine®; HCP--Colgate Plax®; LED LCU, LS--saliva (control); LPT--Pepsi Twist®; LLC--Listerine®; LCP--Colgate Plax®. The degree of conversion analysis and the measure of the peak area at 2,930 cm-1 (organic matrix) of resin composite were done by Fourier-transform Raman spectroscopy (baseline, after 7 and 14 days). The data were subjected to multifactor analysis of variance (ANOVA) at a 95% confidence followed by Tukey's HSD post-hoc test. The DC ranged from 58.0% (Halogen) to 59.3% (LED) without significance. Differences in the peak area between LCUs were found after 7 days of storage in S and PT. A marked increase in the peak intensity of HLC and LLC groups was found. The soft-start light-activation may influence the chemical degradation of organic matrix in resin composite. Ethanol contained in Listerine® Cool Mint mouthwash had the most significant degradation effect. Raman spectroscopy is shown to be a useful tool to investigate resin composite degradation.
authors: Department of Dental Materials and Operative Dentistry, School of Dentistry, University of Vale do Paraíba, UNIVAP, São José dos Campos, SP, Brazil. lesoares@univap.br
authors: Luís Eduardo Silva
authors: LE
authors: Soares
authors: Sídnei
authors: S
authors: Nahórny
authors: Airton Abrahão
authors: AA
authors: Martin
mesh_terms: D002253:Carbonated Beverages; D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental; D003764:Dental Materials / Q000737:chemistry / Q000378:metabolism*; D004338:Drug Combinations; D006801:Humans; D008422:Materials Testing; D009067:Mouthwashes; D053761:Nanocomposites / Q000737:chemistry*; D012459:Salicylates; D012464:Saliva, Artificial; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013729:Terpenes
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D004338:Drug Combinations; D009067:Mouthwashes; D012459:Salicylates; D012464:Saliva, Artificial; D013729:Terpenes; C057473:Listerine