Bond Strength of light-cured Composite Resin Using Various Light Sources

The purposes of this study were to quantify and compare the tensile bonding strengths of light-cured composite resin at 3, 6, 9, and 12 seconds with a xenon plasma arc light and 40 seconds with a conventional tungsten-quartz halogen light using an Instron universal testing machine and debonded interfaces with adhesive remaining index (ARI) under scanning electron microscopy. The human tooth samples utilized in this experiment were extracted for orthodontic reasons. It was found that the bonding strengths achieved with Aurys E (micro-xenon light) after 9 and 12 seconds of exposure did not statistically differ from that achieved by Translux CL (halogen light) after 40 seconds of exposure. The majority of ART scores in those groups were 1 (10%~50% of the adhesive remained on the bracket base). Our results suggest that Aurys E might be a better alternative for light curing, since it allows for a greatly shortened treatment time (of at least 9 seconds), but does not compromise the bonding strength or debonded interface.