Er,Cr:YSGG laser irradiation influence on Y-TZP bond strength to resin cement $ Wanessa M.F. Aras a , Juliana S.M. Barroso b , Alberto Blay c , José Augusto Rodrigues d , Alessandra Cassoni d,n a Graduate Studies Division, Department of Restorative Dentistry, School of Dentistry, State University of Feira de Santana, Bahia, Brazil b Department of Restorative Dentistry, School of Dentistry, Guarulhos University, Guarulhos, Brazil c Private office at São Paulo, Brazil d Dental Research and Graduate Studies Division, Department of Restorative Dentistry, School of Dentistry, Guarulhos University, Guarulhos, Brazil article info Article history: Received 28 April 2016 Received in revised form 25 May 2016 Accepted 27 May 2016 Available online 28 May 2016 Keywords: Zirconia Bond strength Er,Cr:YSGG laser abstract The aim of this study was to evaluate Y-TZP surface pretreatment with different protocols on microshear bond strength (μSBS) ceramic-cement interface. One hundred and sixty pre-sintered IPS e-max ZirCAD (Ivoclar-Vivadent) blocks were randomly divided into sixteen groups according to surface treatment (n ¼20): G1- no treatment (control); G2- ceramic primer; G3- tribochemical silica coating; G4- tribo- chemical silica coating þprimer; G5- airborne particle abrasion (Al 2 O 3 ); G6- airborne particle abrasion (Al 2 O 3 ) þprimer; G7- Er,Cr:YSGG laser; G8- Er,Cr:YSGG laser þprimer. All specimens were sintered before surface treatment, except lasers groups, which were sintered after laser irradiation. Ceramic blocks were bonded with Panavia F resin cement (Kuraray, Okayama, Japan) (n ¼10) or RelyX ARC (3M ESPE, St. Paul, MN, USA) (n ¼10). The μSBS tests were carried out in a universal testing machine at a speed of 1mm/min after 24 h (n ¼5) or 6 months storage (n ¼5). Differences were found for both resin cements and storage conditions in relation to μSBS values (p o0.05). However, no significant difference for interaction be- tween factors was observed in cemented blocks with RelyX ARC. Panavia F resin cement showed sig- nificant differences for interaction between factors (p o0.05). Laser treatment was not sufficient to in- crease μSBS values between Y-TZP and resin cements. Tribochemical silica coating followed by primer achieved the highest immediate μSBS values. The storage did not affect negatively μSBS values to both evaluated cements. & 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved. 1. Introduction Clinical success of polycrystalline ceramics depends on ade- quate adhesion to dental elements, which allows microleakage prevention, increased retention, better marginal adaptation, and higher fracture resistance [1–5]. Chemical and/or mechanical sur- face treatment provides a reliable adhesive bonding to resin ce- ments and ceramic on metal-free prosthetic restorations [3,4]. However, several studies postulate about the difficulties of ob- taining adhesion of these materials to dental structures because their superficial characteristics and composition compromise clinical longevity rehabilitation treatment [2–4,6–9]. Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) is a biocompatible and aesthetic material that presents particularly superior mechanical properties when compared to feldspatic, leucite, and lithium disilicate ceramics [10]. Although conventional techniques for cementation with zinc phosphate and resin-mod- ified glass ionomer cement can be applied to zirconia surface, adhesive cementation has been recommended as more appro- priate to obtain marginal sealing and adequate retention [4,11]. However, to achieve a stable bond with adhesive cementation, it is necessary to prepare the ceramic surface with chemical-mechan- ical or mechanical treatments [12]. Ceramic surfaces without silica dioxide are not conventionally conditioned by hydrofluoric acid and constitute major problems for adhesive cementation [1,3,4,6,9]. In order to overcome this difficulty, different protocols have been used, such as airborne particle abrasion [4,13–17] tribochemical silica coating or silicati- zation [14,15], and selective infiltration technique [16,18]. Recently, laser treatment has been investigated, using different wavelengths, such as Er:YAG, Nd:YAG, CO 2 and Er,Cr:YSGG Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/ceramint Ceramics International http://dx.doi.org/10.1016/j.ceramint.2016.05.180 0272-8842/& 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved. ☆ Supported by FAPESP (São Paulo Research Foundation, Grant no. 2014/14839-0). n Correspondence to: Universidade Guarulhos, Pós Graduação em Odontologia, Praça Teresa Cristina, 229, Centro - Guarulhos, SP CEP 07023-070, Brazil. E-mail address: acassoni@prof.ung.br (A. Cassoni). Ceramics International 42 (2016) 13790–13795