title: Odontological light-emitting diode light-curing unit beam quality.
abstract: The distribution of light intensity of three light-curing units (LCUs) to cure the resin-based composite for dental fillings was analyzed, and a homogeneity index [flat-top factor (FTF)] was calculated. The index is based on the M2 index, which is used for laser beams. An optical spectrum analyzer was used with an optical fiber to produce an x-y power profile of each LCU light guide. The FTF-calculated values were 0.51 for LCU1 and 0.55 for LCU2, which was the best FTF, although it still differed greatly from the perfect FTF = 1, and 0.27 for LCU3, which was the poorest value and even lower than the Gaussian FTF = 0.5. All LCUs presented notably heterogeneous light distribution, which can lead professionals and researchers to produce samples with irregular polymerization and poor mechanical properties.
authors.affiliation: Universidade Federal Fluminense, Faculdade de Odontologia, Rua São Paulo, 28, CEP 24020-150, Niteroi, RJ, Brazil.
authors.forename: Thales Ribeiro
authors.initials: TR
authors.lastname: de Magalhães Filho
authors.affiliation: Universidade Federal Fluminense, Faculdade de Odontologia, Rua São Paulo, 28, CEP 24020-150, Niteroi, RJ, Brazil.
authors.forename: Karin de Mello
authors.initials: Kde M
authors.lastname: Weig
authors.affiliation: Universidade Federal do Rio de Janeiro, COPPE-UFRJ, Rio de Janeiro, RJ, Brasil, Engenharia Elétrica, c.p. 68504, CEP: 21941-972l, Rio de Janeiro, Brazil.
authors.forename: Marcelo Martins
authors.initials: MM
authors.lastname: Werneck
authors.affiliation: Universidade Federal do Rio de Janeiro, COPPE-UFRJ, Rio de Janeiro, RJ, Brasil, Engenharia Metalúrgica e de Materiais, c.p. 68505, CEP: 21941-972l, Rio de Janeiro, Brazil.
authors.forename: Célio Albano
authors.initials: CA
authors.lastname: da Costa Neto
authors.affiliation: Universidade Federal do Rio de Janeiro, COPPE-UFRJ, Rio de Janeiro, RJ, Brasil, Engenharia Metalúrgica e de Materiais, c.p. 68505, CEP: 21941-972l, Rio de Janeiro, Brazil.
authors.forename: Marysilvia Ferreira
authors.initials: MF
authors.lastname: da Costa
mesh_terms: D055117:Curing Lights, Dental; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008027:Light; D055115:Light-Curing of Dental Adhesives / Q000295:instrumentation; D008029:Lighting / Q000295:instrumentation*; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012542:Scattering, Radiation; D012666:Semiconductors