###### Abstract  
The introduction of new ceramic materials for dental restorations is currently a reality; however, little information is available on their surface treatment for the bonding process. Furthermore, surface treatment with plasma on ceramic materials has been recently introduced, although not many studies are available. The aim of this study was to evaluate the surface properties of a leucite-reinforced feldspar ceramic (LIC) and resin matrix ceramic (RMC) after low-pressure plasma treatment. From each material, 48 discs were prepared and subject to surface treatment. The LIC group was treated by hydrofluoric acid (HF) (LIC-HF), plasma with oxygen (LIC-O2), and plasma with argon (LIC-Ar). The RMC group was treated by sandblasting with alumina (RMC-SB), plasma with oxygen (RMC-O2), and plasma with argon (RMC-Ar). The groups whose surfaces were not subjected to treatment were considered as the control group. Surface wettability and roughness was analyzed. The results showed significant differences among the treatments for both ceramics regarding wettability and roughness. Plasma treatments increased the wettability and had a very low effect on the roughness. Plasma treatments achieved similar values for both surface properties in each ceramic group with no differences between both treatments. Plasma treatment seems to be a promising alternative for ceramic surface treatments since it increased the surface energy of the ceramics analyzed and hardly affects the roughness. Further studies are necessary to evaluate the effect of plasma treatment on the bond strength of ceramics. adhesion; plasma; low-pressure plasma; surface treatment; dental ceramics [table]cap  
into conventional technology, facilitating the fabrication of the restorations [6], and it has become a part of daily practice in dentistry [7]. In recent years, several developments have improved the CAD-CAM technology, especially concerning the precision in their marginal adaptation and shortening the manufacturing time [3; 5; 8; 9]. Furthermore, with the use of CAD-CAM technology, there has been an increase in the materials to be used to fabricate the restorations, including glass-ceramic, zirconia ceramic, and resin matrix ceramic (RMC), among others [5; 10; 11]. Cementation is an important process for clinical success of ceramic restorations [12]. There is consensus regarding glass-ceramic restorations, which should be cemented with adhesive cements for reinforcement and support [13; 14]. However, for polycrystalline ceramics, clinical studies reveal comparable survival rates with conventional or adhesive cementation [14; 15], and for RMC, due to their recent introduction, there are few studies and there is a need of clinical protocols [1; 5; 11; 16; 17]. Resin bonding cementation requires the pretreatment of the surfaces to be adhered, both the tooth and the restoration, increasing the complexity compared to conventional cementation [14]. The surface of the ceramic material needs to be sufficiently rough during the bonding process to obtain the appropriate retention [5]. Several surface treatments have been proposed to improve the bonding of resin cements to ceramic, and the composition of the ceramic to be adhered is an important factor that must be taken into account [1; 11; 14]. The most frequent pretreatments methods used are acid etching, air abrasion, or a combination of them [10]. It is very important to select the type of pretreatment, concentration, exposure time, and cleaning method. Over exposure of the material, or improper use of the type of treatment, can cause microcracks in the material, which would cause a decrease in flexural strength [18]. Feldspathic ceramics and their derivatives, such as ceramics reinforced with synthetic crystals or ceramics infiltrated with resin, are materials suitable to be etched. The most commonly used method is hydrofluoric acid (HF) in concentrations of around 5-10%, and with exposure times of 20-60 s [19].