294EVALUATION OF SURFACE ROUGHNESS AND COLOUR SUSTAINABILITY OF INDIRECT COMPOSITE AFTER DIFFERENT POLISHING PROTOCOLSThe effect of polishing with two different systems, Sof-Lex and Enhance, on surface roughness and colour resistance of indirect composite has been investigated. Discs from In:Joy composite (n=21, 2x8 mm) were polymerized and divided into 3 groups. Two of them were subjected to finishing and polishing procedures. Non-polished and polished specimens’ surfaces have been imaged by scanning electron microscopy. Surface roughness was measured with mechanical roughness tester. Colour resistance was studied by absorption of methylene blue from the specimens. The smoothest surface was presented by the non-polished (control) group which was significantly different from the polished groups. Polished specimens were more susceptible to dye penetration. The susceptibility to the staining was not associated with the surface roughness. Both polishing systems exhibited the same level of performance.d_anny@abv.bgResearch582015Resin composites,Roughness,Polishing,ColourYordanka I. Uzunova,Ivan A. FIlipov, Stela B. Nicheva Department of Chemistry and Biochemistry, Faculty of Pharmacy, Medical University-Plovdiv, Plovdiv, Bulgaria.,Department of Operative Dentistry and Endodontics, Dental Faculty, Medical University-Plovdiv, Plovdiv, Bulgaria.,Department of Operative Dentistry and Endodontics, Dental Faculty, Medical University-Plovdiv, Plovdiv, Bulgaria.