title: Effect of High-Irradiance Light-Curing on Micromechanical Properties of Resin Cements.
abstract: This study investigated the influence of light-curing at high irradiances on micromechanical properties of resin cements. Three dual-curing resin cements and a light-curing flowable resin composite were light-cured with an LED curing unit in Standard mode (SM), High Power mode (HPM), or Xtra Power mode (XPM). Maximum irradiances were determined using a MARC PS radiometer, and exposure duration was varied to obtain two or three levels of radiant exposure (SM: 13.2 and 27.2 J/cm2; HPM: 15.0 and 30.4 J/cm2; XPM: 9.5, 19.3, and 29.7 J/cm2) (n= 17). Vickers hardness (HV) and indentation modulus (EIT) were measured at 15 min and 1 week. Data were analyzed with nonparametric ANOVA, Wilcoxon-Mann-Whitney tests, and Spearman correlation analyses (α= 0.05). Irradiation protocol, resin-based material, and storage time and all interactions influencedHVandEITsignificantly (p≤ 0.0001). Statistically significant correlations between radiant exposure andHVorEITwere found, indicating that high-irradiance light-curing has no detrimental effect on the polymerization of resin-based materials (p≤ 0.0021). However, one resin cement was sensitive to the combination of irradiance and exposure duration, with high-irradiance light-curing resulting in a 20% drop in micromechanical properties. The results highlight the importance of manufacturers issuing specific recommendations for the light-curing procedure of each resin cement.
authors.affiliation: Department of Preventive, Restorative, and Pediatric Dentistry, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010 Bern, Switzerland.
authors.forename: Anne
authors.initials: A
authors.lastname: Peutzfeldt
authors.affiliation: Department of Preventive, Restorative, and Pediatric Dentistry, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010 Bern, Switzerland.
authors.forename: Adrian
authors.initials: A
authors.lastname: Lussi
authors.affiliation: Department of Preventive, Restorative, and Pediatric Dentistry, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010 Bern, Switzerland.
authors.forename: Simon
authors.identifier: 0000-0001-9390-5412
authors.initials: S
authors.lastname: Flury
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental; D003764:Dental Materials / Q000737:chemistry*; D006244:Hardness; D008422:Materials Testing / Q000379:methods; D058105:Polymerization; D019279:Resin Cements / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D019279:Resin Cements; C111840:flowable hybrid composite