title: Evaluation of depth of cure and Knoop hardness in a dental composite photo-activated using different methods.
abstract: The aim of this study was to evaluate the depth of cure and Knoop hardness in the P60 composite resin photo-activated using different methods. A bipartite brass matrix (3 mm in diameter X 11 mm in height) was filled with the composite and photo-activation was performed using continuous light, exponential light, intermittent light, plasma arc curing (PAC) or light-emitting diodes (LED). After opening the matrix, the uncured material was removed with a steel spatula and the polymerized composite was measured using a pachymeter. The specimens were then included in self-curing acrylic resin and worn longitudinally and the hardness was measured on the surface and at depths of 1, 2, 3, 4 and 5 mm. The data were analyzed by ANOVA and Tukey's test (5%). The results showed that the depth of cure was higher with the intermittent light, followed by continuous light, exponential light, PAC and LED methods. Up to a depth of 2 mm, all methods revealed similar hardness values, but there were differences between them at other depths, at which LED demonstrated the lowest values followed by PAC.
authors.affiliation: School of Dentistry of Piracicaba, UNICAMP, Piracicaba, SP, Brazil.
authors.forename: Andresa Carla
authors.initials: AC
authors.lastname: Obici
authors.forename: Mário Alexandre Coelho
authors.initials: MA
authors.lastname: Sinhoreti
authors.forename: Lourenço
authors.initials: L
authors.lastname: Correr Sobrinho
authors.forename: Mario Fernando
authors.initials: MF
authors.lastname: de Goes
authors.forename: Simonides
authors.initials: S
authors.lastname: Consani
mesh_terms: D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects; D055117:Curing Lights, Dental; D003764:Dental Materials / Q000737:chemistry* / Q000528:radiation effects; D003775:Dental Polishing / Q000295:instrumentation; D006244:Hardness; D006801:Humans; D008027:Light; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D011829:Radiation Dosage; D012825:Silicon / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors
chemical_list: D017554:Carbon Compounds, Inorganic; D003188:Composite Resins; D003764:Dental Materials; C438835:Filtek P60 Composite Resin; D011108:Polymers; C517455:carborundum; D012825:Silicon