The reproducibility of electronic color measurements of the marginal gingiva

Introduction This study evaluated the reproducibility of electronic color determination system evaluations of the marginal gingiva, which could be important for adhesive cervical fillings or prosthetic restorations that imitate the gingiva. Material and methods In 50 subjects, the L *, a *, and b * color coordinates were evaluated five times at a point in the marginal area of a central incisor using different electronic color determination systems: (SP) Shadepilot, (ES) Easyshade, (CE) Crystaleye, and (SV) X-Rite. The mean color difference (ΔE) and its standard deviation between the five measurements from each participant were calculated separately for each device. Further ICC for interdevice reliability was determined. Results The L *, a *, and b * color coordinates and ΔE values differed significantly among the systems ( p < 0.001). Within each patient and measurement system, ΔE ranged from 1.4 to 3.2 (SD 1.1–2.5), L * from 2.6 to 5.7 (SD 2.6–5.7), a* from 11.9 to 21.3 (SD 3.6–3.9), and b* from 15.1 to 28.9 (SD 1.7–4.3). Interdevice reliability ranged between 0.675 and 0.807. Conclusions Color determination of the marginal gingiva using the electronic tooth color determination systems tested herein showed limited reproducibility. The results obtained with the different measurement systems differed enormously. Clinical relevance These results show that the electronic color measurement devices tested allow no high reproducible determination of color coordinates of the marginal gingiva.