title: Effect of dual-peak LED unit on the polymerization of coinitiator-containing composite resins.
abstract: The purpose of the present study was to evaluate the effect of dual-peak LED on the polymerization of coinitiator-containing composite resins. For this, microhardness, degree of conversion (DC), and polymerization shrinkage were evaluated. Specimens (coinitiator-containing: Aelite LS Posterior, Tetric EvoCeram, and Vit-l-escence; only camphorquinone-containng: Filtek Z350 and Grandio) were light cured using a quartz-tungsten-halogen (QTH: OP), a single-peak light-emitting diode (LED) (L. E. Demetron: DM), and a dual-peak LED (G-light: GL), respectively. All specimens light cured using GL showed the highest microhardness both on the top and bottom surfaces compared with the values obtained using the rest light-curing units (LCUs). DC had no consistent trend correspond to the LCU, but rather product specific. OP yielded the lowest polymerization shrinkage on the specimens. The coinitiator-containing composite resins achieved the highest microhardness by the dual-peak LED (GL). However, the influence of GL on DC and polymerization shrinkage of the specimens was not consistent.
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Medical Research Institute, Pusan National University Hospital, Pusan National University, Yangsan, Korea.
authors.forename: Dong-Soo
authors.initials: DS
authors.lastname: Lee
authors.forename: Tae-Sung
authors.initials: TS
authors.lastname: Jeong
authors.forename: Shin
authors.initials: S
authors.lastname: Kim
authors.forename: Hyung-Il
authors.initials: HI
authors.lastname: Kim
authors.forename: Yong Hoon
authors.initials: YH
authors.lastname: Kwon
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects*; D055117:Curing Lights, Dental; D006244:Hardness; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D058567:Photoinitiators, Dental / Q000737:chemistry / Q000528:radiation effects*; D058105:Polymerization; D012666:Semiconductors
chemical_list: D003188:Composite Resins; D058567:Photoinitiators, Dental