title: Mechanical properties of light-curing composites polymerized with different laboratory photo-curing units.
abstract: This study aimed to analyze the microhardness (KHN) and diametral tensile strength (DTS) of two hybrid resin composites (TPH Spectrum and Filtek Z250). To this end, the composites were polymerized with six laboratory photo-curing units (LPUs) and the results compared with an alternative polymerization method using conventional halogen light source in conjunction with additional polymerization in an autoclave (15 minutes/100 degrees C). LPUs were used following the manufacturers' instructions. Diametral tensile strength and Knoop hardness tests were conducted for all groups (n=5). Data were statistically compared using ANOVA and Tukey's test (alpha = 0.05). Among the LPUs, the one that provided light curing in conjunction with heat and nitrogen pressure resulted in a significant increase in KHN and DTS of resin composites. Between the resin composites, Filtek Z250 showed higher hardness values than TPH Spectrum. It was concluded that the use of alternative polymerization with conventional light polymerization and autoclave was feasible with a wide implication for the general public in terms of reduced dental treatment cost.
authors.affiliation: Department of Operative Dentistry, Dental School, Federal University of Uberlindia, Pard 1720 2B24, 38400-902, Minas Gerais, Brazil.
authors.forename: Gisele Rodrigues
authors.initials: GR
authors.lastname: da Silva
authors.forename: Paulo Cezar
authors.initials: PC
authors.lastname: Simamoto-Júnior
authors.forename: Adérito Soares
authors.initials: AS
authors.lastname: da Mota
authors.forename: Carlos José
authors.initials: CJ
authors.lastname: Soares
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins / Q000528:radiation effects*; D003365:Costs and Cost Analysis; D003748:Dental Equipment; D003799:Dental Stress Analysis; D005240:Feasibility Studies; D006244:Hardness; D008027:Light; D044367:Phase Transition; D018709:Statistics, Nonparametric; D013674:Technology, Dental / Q000191:economics; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; C444701:Filtek Z250; C467914:TPH spectrum