Background: Light-cured bonding systems have been widely accepted among orthodontists. Various light curing units are available now. Recently light emitting diode (LED) has been introduced alongside halogen light curing units. There is a lack of information on the advantages and disadvantages of different light curing systems. The aim of this in vitro study was to compare the shear bond strength of orthodontic brackets and adhesive remnant index (ARI) of an adhesive cured with two different orthodontic light sources i.e. LED and halogen.
Methods: Forty four (22 in each group) extracted human premolars without any defects were etched with 37% phosphoric acid and cleansed with water spray and air dried. The sealant (Ortho Solo) was applied on the tooth surface and the brackets were bonded using adhesive (Enlight). Adhesives were cured with Halogen (Litex) and LED (D-LUX) for 40 seconds. Then the specimens were debonded later using a universal testing machine, with crosshead speed of 0.2 mm/min until the brackets were detached. Adhesive remnant index (ARI) scores were assessed under stereomicroscope at ×10 magnification.