title: Effect of light-emitting diode and halogen light curing on the micro-hardness of dental composite and resin-modified glass ionomer cement: an in vitro study.
abstract: OBJECTIVE
  This in vitro study was conducted to evaluate and compare the micro-hardness of composite resin and resin-modified glass ionomer cement using light-emitting diode (LED) and halogen curing and also to inter-compare the effect of LED and halogen curing.
  
  
  METHODS
  The study sample comprised of 4 stainless steel plates with a thickness of 2 mm. For these stainless steel plates, holes were made to a diameter of 3 mm. The samples were divided into 4 groups of 8 each and labeled as group I, group II, group III, group IV, thus making provision for the two different modes of light exposure. In each group, the hole was restored with its respective restorative material and cured with light-curing unit according to manufacturer instructions. The results were statistically analyzed using Mann-Whitney test.
  
  
  CONCLUSIONS
  It was concluded that the curing efficacy of the LED lamp was comparable to that of conventional halogen lamp, even with a 50% reduction in cure time, and resin composite (Filtek Z-250) presented the highest hardness values, whereas complete hardening of resin-modified glass ionomer cement (RMGIC) (Vitremer) was observed because of its self-curing system even after the removal of light source.
authors.affiliation: Department of Pedodontics and Preventive Dentistry, Inder Prastha Dental College and Hospital, Ghazizbad 46/1 Site No. IV, Industrial Area, Sahibabad, Ghazizbad, India. drmanishbhalla@gmail.com
authors.forename: M
authors.initials: M
authors.lastname: Bhalla
authors.forename: D
authors.initials: D
authors.lastname: Patel
authors.forename: N D
authors.initials: ND
authors.lastname: Shashikiran
authors.forename: R M
authors.initials: RM
authors.lastname: Mallikarjuna
authors.forename: T M
authors.initials: TM
authors.lastname: Nalawade
authors.forename: H K
authors.initials: HK
authors.lastname: Reddy
mesh_terms: D003188:Composite Resins / Q000737:chemistry / Q000528:radiation effects*; D055117:Curing Lights, Dental / Q000145:classification* / Q000592:standards; D005899:Glass Ionomer Cements / Q000737:chemistry / Q000528:radiation effects*; D006244:Hardness; D006801:Humans; D055115:Light-Curing of Dental Adhesives / Q000295:instrumentation* / Q000592:standards; D008422:Materials Testing; D058105:Polymerization; D019279:Resin Cements / Q000737:chemistry / Q000528:radiation effects*; D055116:Self-Curing of Dental Resins; D013997:Time Factors
chemical_list: D003188:Composite Resins; C444701:Filtek Z250; D005899:Glass Ionomer Cements; D019279:Resin Cements; C084550:Vitremer