13th World Congress for Laser Dentistry

26-28, April 2012

Barcelona, Spain

Meeting Abstract

Sponsors: World Federation for Laser Dentistry

- Oral Presentation 87

TITLE: The efficiency of Er,Cr:YSGG laser in recycling ceramic orthodontic brackets.

AUTHORS: Ashrafpour E, Ahrari F, Fekrazad R, Kalhori K, Forouzanfar A, Ramtin M.

Dental Research Center, Mashhad University of Medical Sciences.

SOURCE: Med Oral Patol Oral Cir Bucal. 2012 May 1;17(Supplement1):S87.

* doi:10.4317/medoral.17643586

http://dx.doi.org/10.4317/medoral.17643586

Abstract

It is known that Erbium lasers are effective for composite removal but the information is minimal on their efficacy for recycling of ceramic brackets. To evaluate the effect of Er,Cr:YSGG laser in removing adhesive from bases of debonded ceramic brackets and to determine the shear bond strength of rebonded brackets. 30 premolars were divided in 3 groups, then bonded with mechanical retention ceramic brackets according to the following conditions: 1) new brackets as control, 2) debonded brackets cleaned of adhesive with Er,Cr:YSGG laser at 3.5W, and 3) debonded brackets cleaned of adhesive with same laser at 4W. Before bonding we determined the percentage of remaining adhesive on the bases of reconditioned brackets by using stereomicroscopic images (image processing software). The brackets were then tested in shear mode in a universal testing machine and the adhesive remnant index scores were determined. The percentage of remaining adhesive on the bases of brackets cleaned with Er,Cr:YSGG laser at 4W(3.1%) was significantly lower than that of the 3.5W laser group (5.9%) (P=0.01). No significant difference was found in bond strength between the new and the reconditiond brackets. The frequency of bond failure at the enamel-adhesive interface was lower in laser-reconditioned brackets compared to new ones. Application of Er,Cr:YSGG laser was evaluated efficient because it produced comparable bond strengths to new brackets while reducing the risk of enamel damage during debonding.