Curing efficiency of three light emitting diode units at different curing profiles.

ABSTRACT

Context High‑intensity light emitting diode lamps with reduced exposure time to bond orthodontic attachments have been introduced to save the valuable clinical time. Aims: To evaluate the shear bond strength of brackets cured using three different light emitting diode curing units having different intensities and curing times, to compare the effect of different exposure methods on bond strength, and to compare the amount of remnant adhesive on tooth after debonding. Settings and Design: Study conducted on 120 brackets bonded to extracted premolar teeth cured by using three light‑emitting diode (LED) units. Methods: One hundred and twenty adhesive precoated metal brackets (Gemini series, 3M Unitek) were cured using three LED curing units (3M ESPE, ELIPAR, S10; Ortholux™ LED; Ortholux™ Luminous Curing Light). Universal testing machine was used to record shear bond strength. Residual adhesive remaining on the teeth was assessed by the modified adhesive remnant index. Statistical Analysis: After calculating mean and standard deviation for each group, post hoc Tukey and Kruskal–Wallis tests were employed to find the significant difference. Results: Comparison showed highest shear bond strength for Group 1A followed by 3A and lowest for Group 3B. Statistically significant difference was noticed in comparing shear bond strength recorded in Group 1A, Group 2A, and Group 3A with Group 1B, Group 2B, and Group 3B. Conclusions: Reduction of exposure time to 6 s with high‑intensity curing light seemed to be clinically acceptable and should be recommended. Curing of metal brackets with single exposure from buccal side showed lower shear bond strength values.