Hindawi Publishing Corporation he Scientiic World Journal Volume 2013, Article ID 719182, 5 pages http://dx.doi.org/10.1155/2013/719182 Research Article Evaluation of Self-Etching Adhesive and Er:YAG Laser Conditioning on the Shear Bond Strength of Orthodontic Brackets Rosalía Contreras-Bulnes, 1 Rogelio J. Scougall-Vilchis, 1 Laura E. Rodríguez-Vilchis, 1 Claudia Centeno-Pedraza, 1 Oscar F. Olea-Mejía, 2 and María del Carmen Z. Alcántara-Galena 1 1 Universidad Aut´ onoma del Estado de M´ exico, Facultad de Odontolog´ ıa, Centro de Investigaci´ on y Estudios Avanzados en Odontolog´ ıa (CIEAO), Jes´ us Carranza Esquina Paseo Tollocan, Colonia Universidad, 50130 Toluca, MEX, Mexico 2 Universidad Aut´ onoma del Estado de M´ exico Universidad Nacional Aut´ onoma de M´ exico, Centro Conjunto de Investigaci´ on en Qu´ ımica Sustentable (CCIQS), Km 14.5 Carretera Toluca-Ixtlahuaca, San Cayetano de Morelos, 50200 Toluca, MEX, Mexico Correspondence should be addressed to Rosal´ ıa Contreras-Bulnes; rcontrerasb@uaemex.mx Received 15 August 2013; Accepted 16 September 2013 Academic Editors: M. Irie and T. Morotomi Copyright © 2013 Rosal´ ıa Contreras-Bulnes et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. he purpose of this study was to evaluate the shear bond strength, the adhesive remnant index scores, and etch surface of teeth prepared for orthodontic bracket bonding with self-etching primer and Er:YAG laser conditioning. One hundred and twenty bovine incisors were randomly divided into four groups. In Group I (Control), the teeth were conditioned with 35% phosphoric acid for 15 seconds. In Group II the teeth were conditioned with Transbond Plus SEP (5sec); III and IV were irradiated with the Er:YAG 150 mJ (11.0 J/cm 2 ), 150 mJ (19.1 J/cm 2 ), respectively, at 7–12Hz with water spray. Ater surface preparation, upper central incisor stainless steel brackets were bonded with Transbond Plus Color Change Adhesive. he teeth were stored in water at 37 ∘ C for 24 hours and shear bond strengths were measured, and adhesive remnant index (ARI) was determined. he conditioned surface was observed under a scanning electron microscope. One-way ANOVA and chi-square test were used. Group I showed the signiicantly highest values of bond strength with a mean value of 8.2 megapascals (MPa). he lesser amount of adhesive remnant was found in Group III. he results of this study suggest that Er:YAG laser irradiation could not be an option for enamel conditioning. 1. Introduction Surface conditioning is essential to increase bond strength to enamel. he direct bonding of orthodontic brackets with composite resins has been considered as one of the most signiicant developments in orthodontics [1]. he enamel etching technique has been accepted as a routine procedure for bonding orthodontic brackets to the tooth surfaces [2]. However, a potential disadvantage is the possibility of decalciication, which leaves the enamel susceptible to caries attack, especially under orthodontic attachments [3–5]. here is a need to simplify clinical procedures and minimize enamel loss while maintaining clinically useful bond strength [6, 7]. In an efort to improve the adhesion procedure, reduce loss of enamel, prevent saliva contamination, and save chairside time, self-etching primers (SEPs) have been introduced in the market [8, 9]. he use of Er:YAG laser for caries removal and cavity preparation was approved in 1997 by the US Food and Drug Administration (FDA) [10]. Although this laser was introduced into dentistry for the ablation of dental hard tissue [11, 12], laser sub ablation has become available as an alternative to acid etching of enamel and also dentine [13]. Research on enamel surface roughness showed that