The objective of this study was to investigate whether a systematically arranged shade guide system (Vita 3D-Master) allows clinicians to achieve a better shade match of a restoration, as compared to a conventional shade guide with a design based on empirical values (Vita Classical).Fifty-nine restorations in 42 patients being treated by student clinicians were assessed. Using 1 of the 2 shade systems assigned randomly, each student independently determined the tooth shade. With the aid of a visual rating scale, the accuracy of the shade match of the finished restoration was assessed.All restorations whose shades had been determined with the 3D-Master could be placed without any further shade corrections. In contrast, almost 17% of restorations determined with the conventional system required subsequent shade modifications. The match of the shades selected with the 3D-Master was judged significantly better by the clinicians.Within the limitations of the study, clinicians with less clinical experience who use a system that guides them through the shade-taking procedure in a relatively systematic manner will be more successful in selecting the correct tooth shade and in avoiding shade corrections. Clinical assessment of the restoration shades showed significant differences between the shade guide with a systematic design and that based on empirical values.