Evaluation of tooth shade selection in dentistry: Effects of clinical experience, current illumination sources, and different shade guides using digital analysis

The aim of the study is to evaluate the shade-matching accuracy of observers with different levels of professional experience, using different shade guides under different lighting conditions. A total of 60 participants (n=20), consisting of prosthodontics research assistants (AR), 5th-year dental students who had completed clinical training (SÖ), 3rd-year dental students who had received theoretical training in shade selection (PÖ), selected shades (A2, B2, C2, D2) from the VITA Classical (VC), using different light sources [daylight (DL) and Smile Lite (SL); light-correcting device)] and different shade guides [VC and Toothguide 3D-MASTER (V3D)]. The L*a*b* values of the shades were measured with a spectrophotometer (control group). Data were scored as follows: 0ΔE*00=0, 0–1.8ΔE*00=1, >1.8ΔE*00=2. Statistical analyses were performed using Kruskal-Wallis, Mann-Whitney U, Bonferroni and Spearman's correlation tests (p<0.01). Usage of light-correcting device showed a significant difference only in Group AR in B2 and C2 shade selections with VC (p<0.01). When VC and V3D were compared using daylight, Groups AR and SÖ showed significant differences in B2 and D2 shade selections, Group PÖ showed a significant difference in D2 (p<0.01). When VC and V3D were compared with light-correcting device, Group AR showed significant differences in all shade selections, Group SÖ and PÖ showed significant differences in B2 and D2 (p<0.01). Group AR made more accurate selections compared to other participant groups. For all shade guides, when Group AR was compared with Group SÖ, a significant difference was found in C2 shade selection. When Groups AR and SÖ were compared with Group PÖ, significant differences were found in A2 and C2 shade selections (p<0.017). Usage of different shade guides and light-correcting device affected the ideal shade selection. Clinicians with more clinical experience made shade choices closer to the ideal. Light-correcting device was observed to be more effective, especially with experienced observers and using VC shade guide. Keywords: Light correcting device, Professional experience, Shade, Shade guide