title: Influence of the photoinitiator system and light photoactivation units on the degree of conversion of dental composites.
abstract: The aim of this study was to observe the influence of two light polymerization units (LED or halogen light) on the degree of conversion (DC) of three dental composites with lighter shades and a different photoinitiator system. The top (T) and bottom (B) surfaces of 60 discs of composite resin (Filtek™ Supreme, Filtek™ Z250, Tetric™ Ceram Bleach) cured either by LED or by halogen lamp (HL) were studied using an FT-Raman spectrometer. The degree of conversion (DC) was evaluated by following the changes in the intensity of the methacrylate C=C stretching mode at 1640 cm⁻¹. The calculated DC ranged from 54.2% (B) to 73.4% (T) and from 60.2% (B) to 76.6% (T) for the LED and HL, respectively. LED and halogen devices were able to produce an adequate DC for all the resins tested.
authors.affiliation: Cesmac University Center, Maceió, AL, Brazil.
authors.forename: Isabel Cristina Celerino de Moraes
authors.initials: IC
authors.lastname: Porto
authors.forename: Luis Eduardo Silva
authors.initials: LE
authors.lastname: Soares
authors.forename: Airton Abrahão
authors.initials: AA
authors.lastname: Martin
authors.forename: Vanessa
authors.initials: V
authors.lastname: Cavalli
authors.forename: Priscila Christiane Suzy
authors.initials: PC
authors.lastname: Liporoni
mesh_terms: D003188:Composite Resins / Q000737:chemistry / Q000528:radiation effects*; D055117:Curing Lights, Dental; D008422:Materials Testing; D058567:Photoinitiators, Dental; D058105:Polymerization / Q000528:radiation effects*; D013059:Spectrum Analysis, Raman; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors
chemical_list: D003188:Composite Resins; D058567:Photoinitiators, Dental