o pyr i g h t b y Q u i n t e s sen z A l l e R e c h t e v o r b e h a l t e n E arly types of metal-free ceramics did not enjoy success in dentistry, especially in the posterior region. 33 Howev-er, with the introduction of high-strength ceramic systems to the dental market almost two decades ago, ceramic restora-tions became viable options for posterior teeth. High-strength ceramic systems are expected to provide restorations with sufficient mechanical strength to resist oc-clusal forces as well as deliver more esthetic results than conventional metal-fused-to-ceramic restorations. New ce-ramic systems include ceramic cores reinforced through dis-persion with leucite, 10,16,27,29,32 glass-infiltrated sintered alumina, 5,28 and the use of high-purity alumina 21 or zirconi-um oxide. 30 Bonding of ceramic to dental tissue is based on the ad-hesion of luting cement to the ceramic substrate, together Purpose: The aim of this study was to evaluate the effect of two surface conditioning methods on the microtensile bond strength of a resin cement to three high-strength core ceramics: high alumina-based (In-Ceram Alumina, Procera AllCe-ram) and zirconia-reinforced alumina-based (In-Ceram Zirconia) ceramics. Materials and Methods: Ten blocks (5 x 6 x 8 mm) of In-Ceram Alumina (AL), In-Ceram Zirconia (ZR), and Procera (PR) ceramics were fabricated according to each manufacturer's instructions and duplicated in composite. The specimens were assigned to one of the two following treatment conditions: (1) airborne particle abrasion with 110-μm Al 2 O 3 parti-cles + silanization, (2) silica coating with 30 μm SiO x particles (CoJet, 3M ESPE) + silanization. Each ceramic block was duplicated in composite resin (W3D-Master, Wilcos, Petrópolis, RJ, Brazil) using a mold made out of silicon impression material. Composite resin layers were incrementally condensed into the mold to fill up the mold and each layer was light polymerized for 40 s. The composite blocks were bonded to the surface-conditioned ceramic blocks using a resin ce-ment system (Panavia F, Kuraray, Okayama, Japan). One composite resin block was fabricated for each ceramic block. The ceramic-composite was stored at 37°C in distilled water for 7 days prior to bond tests. The blocks were cut under wa-ter cooling to produce bar specimens (n = 30) with a bonding area of approximately 0.6 mm 2 . The bond strength tests were performed in a universal testing machine (crosshead speed: 1 mm/min). Bond strength values were statistically analyzed using two-way ANOVA and Tukey's test (≤ 0.05).