Objective: To evaluate the vertical misfit between different brands of dental implants and prosthetic abutments, with or without mechanical torque, and to study their possible combination. Study design: Five different brands of implant were used in the study: Biofit (Castemaggiore, Italy), Bioner S.A. (Barcelona, Spain), 3i Biomet (Palm Beach, U.S.A.), BTI (Alava, Spain) and Nobel Biocare (Göteborg, Sweden), with standard 4.1 mm heads and external hexagons, and their respective machined prosthetic abutments. The implant-to-abutment fit/misfit was evaluated at four points (vestibular, lingual/palatine, mesial and distal) between implants and abutments of the same brand and different brands, with or without mechanical torque, using SEM micrographs at 5000X. Image analysis was performed using NIS-Elements software (Nikon Instruments Europe B.V.). Results: Before applying torque, vertical misfit (microgaps) of the different combinations tested varied between 1.6 and 5.4 microns and after applying torque, between 0.9 and 5.9 microns, an overall average of 3.46±2.96 microns. For manual assembly without the use of mechanical torque, the best results were obtained with the combination of the 3i implant and the BTI abutment. The Nobel implant and Nobel abutment, 3i-3i and BTI-BTI and the combination of 3i implant with BTI or Nobel abutment provided the best vertical fit when mechanical torque was applied. Conclusions: The vertical fits obtained were within the limits considered clinically acceptable. The application of mechanical torque improved outcomes. There is compatibility between implants and abutments of different brand and so their combination is a clinical possibility. Key words:Vertical fit, implant, prosthetic abutment, combination.

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Introduction: Today’s dentistry frequently employs bonded partial restorations, which are usually fabricated in ceramic materials. In the last decade, hybrid materials have emerged that attempt to combine the properties of composites and ceramics. Objectives: To evaluate in vitro, by means of a microtensile test, the bond strength between CAD-CAM restorative materials and the cement recommended by their manufacturer. Material and Method: From blocks of CAD-CAM restorative material bonded to composite blocks (Filtek 500®), beams with a bonding area of approximately 1 mm2 were made and divided into four groups: EMAX (IPS e.max CAD® lithium disilicate), VE (VITA Enamic® polymer-infiltrated ceramic matrix), LUA (Lava Ultimate® nano-ceramic resin with sandblasting protocol) and LUS (Lava Ultimate® nano-ceramic resin with silica coating protocol). In each group, perimeter (external) or central (internal) beams were differentiated according to the position in the block. The samples were tested on the LMT 100® microtensile machine. Using optical microscopy, the fractures were categorized as adhesive or cohesive (of the restorative material or composite), and the data were analysed with parametric tests (ANOVA). Results: The LUS group had the highest results (42 ± 20 MPa), followed by the LUA group (38 ± 18 MPa). EMAX had a mean of 34 ± 16 MPa, and VE was the lowest in this study (30 ± 17 MPa). In all groups, the central beams performed better than the perimeter beams. Both EMAX and VE had the most adhesive fractures, while LUA and LUS had a predominance of cohesive fractures. Conclusions: Lava Ultimate® nanoceramic resin with the silica coating protocol obtains the best bond strength values.