This study was carried out as a prospective clinical field study with the aim of evaluating the clinical performance of Equia Fil® with a nanofilled resin coating and the conventional Fuji IX GP® fast with an LC coating according to the World Dental Federation (FDI) restoration material evaluation criteria. The clinical performance of Equia Fil® and Fuji IX GP® fast was evaluated on permanent posterior teeth of 643 adult patients aged between 20 to 80 years old in randomly selected clinics across Germany. Occlusal cavities in posterior permanent teeth were restored with Equia Fil® with a nanofilled, light-cured resin coating (n = 515) and Fuji IX GP® fast with an LC coating (n = 486). Direct clinical assessment as well as photographic assessment and assessment of stone casts of the restorations were made at 1 year, 2 years, 3 years, and 4 years. In 4 years, a total of 1001 fillings from both materials were placed by 111 dentists in 643 patients. Random slope models showed that the Equia filling system had overall lower odds of obtaining a delta event (material needs replacement) in comparison to Fuji IX GP® fast with an LC coating within all models. In both materials, filling size/surface was the most important component affecting the clinical performance of the materials. When measuring the odds of obtaining a delta event (material needs replacement), the odds ratios jumped to approximately 43 and 296 times for class II (two surfaces) and class II mesial-occlusal-distal (three surfaces) respectively in comparison to class I fillings. Both materials showed similar good overall performance in class I cavities; however, when including numbers from both class I and II fillings, the Equia system with a nanofilled resin coating showed better overall performance with fewer failures in all the follow-up intervals. Nonetheless, the percentage of unsatisfactory to poor fillings according to the FDI criteria was relatively high in two-surface class II fillings and higher in three-surface class II fillings for both materials. Deutsches Register Klinischer Studien (German Clinical Trials Register): DRKS00004220. ( www.germanctr.de ). Registration date: 6 Sept 2012.

Visual colour differentiation in clinical research requires colour-competent (CC) participants. The Ishihara colour charts (ICC) have established themselves as the standard for CC screening of colour vision deficiencies (CVD). However, the extent to which the results can be compared with a presentation of the colour charts on a smartphone display (SD) is currently unknown. The aim of this in vitro study was to determine the sensitivity and specificity of the Ishihara colour deficiency test depending on the presentation mode. Dental students (female n = 28; male n = 10; mean age, 23.5 ± 2.65 years; median age, 23.0 ± 13.0 years) evaluated 25 Ishihara test plates on their SD (n = 38) and/or a calibrated monitor (HP monitor, 22-inch; n = 18). The median size of the SD was 6.0 inches. Datasets with more than 2 failed charts were scored. When the Ishihara test charts were presented on a PC screen, the sensitivity was 94.4% and the specificity was 82.4% (0 mistakes: n = 14, <3 failures: n = 3, 14 false answers: n = 1). On the SD, a sensitivity of 96.0% and a specificity of 94.7% were calculated (89.5% were correct; 4 participants [10.5%] made .05). The presentation of ICC on an SD is useful and can be used for the investigation of a possible CVD of large groups. Comparable results to data projection can be achieved with a high degree of certainty. For CVD screening of larger groups (eg, students in preclinical training as part of CC training), the presentation of ICC on the SD can be used. This research was able to demonstrate that the sensitivity and specificity of the usual presentation method (Ishihara's booklet or data projection) is comparable.

Objectives: Visual shade selection is the most commonly used method in dentistry and a challenge for every dentist. However, differences to natural tooth color and the differences of each shade guide are well known. The aim of this paper is to investigate the suitability of two different color scales for determining the color of no‐match templates.Materials and methods: Volunteers (N = 76) selected a shade color of a no‐match template with two shade guides (VITA Classical shade guide (VC) and VITA Linearguide 3D‐Master (V3D LG), both Vita Zahnfabrik). The neutral grey background was laterally illuminated with a color differentiation lamp (Dialite, Eickhorst GmbH). For the volunteers’ accuracy, the triangle's area was used which are emerge by the color coordinates of a template (L_Ta_Tb_T) and the color coordinates of the two decisions (L₁a₁b₁ and L₂a₂b₂). Statistical software was used to evaluate the differences in ΔE₀₀ with α = .01.Results: A deviation in the median of ΔE₀₀ of 7.6 (V3D LG, first choice) to 6.6 (VC, second choice) was detected, while U test showed no significant differences in the median for both color scales. But the triangle's area generated by both shade decisions and tooth color with V3D LG was significant smaller (14.2) then VC (19.2) (P ≤ .001).Conclusions: When comparing both results no significant difference in the subject's shade selection and the shade guides was detected. The new evaluation strategy using the size of the triangle's areas proves the superiority of the V3D LG due to a better distribution of the tooth color shades within the color space.

Visual color determination (VCD) requires color competence and individual training. The aim of this study was to evaluate the deviations in students’ VCD with two different reference scales. The research hypothesis was that none of the color references would provide a better result. Participants evaluated nine templates randomly using two reference scales (VITA-classical (VC) and 3D-Master-Toothguide (3DM_TG)). The color distance to the chosen color (ΔE_ab) was calculated in the CIELAB 2000. The sum’s changes in the parameters (LCh°) represented the target variable. Results were evaluated with non-parametric, rank-scaled methods, utilizing the median with a 25%-75% quartile. The significance level (α = 0.05) is determined using the Student’s t-test. The mean ± 95%CI (SD) was −1.27 ± −1.09 (3.18); the median ΔE₀₀ was −1.49 (−1.97; 0.96) for dC_{3DM_TG}. The determination with VC showed noticeable differences (dC_VC), with a mean ΔE₀₀ of 0.00 ± 0.00 (2.20) and a median ΔE₀₀ of 0.00 (1.17; 1.71). The standard error was 0.19 for the dC_VC and 0.27 for the dC_{3DM_TG}. dC_{3DM_TG} vs. dC_VC showed significant differences at p < 0.001. The dental student’s VCD resulted in color deviations, regardless of the reference template used. The color deviations in hue and chroma were comparable, regardless of the reference scale. VCD’s early implementation in dental education is useful to avoid shade misjudgments and potentially expensive remakes of dentures.

Visual color determination is part of the daily routine in dental practice. However, it is not a part of dental education so far. The aim of this study was to evaluate whether visual or digital tooth color determination of 3D-printed teeth is a reliable tool for inexperienced dentistry students. Preclinical dental students evaluated eleven 3D-printed, tooth-shaped samples (VarseoSmile Crown plus, BEGO, Bremen, Germany) of different color shades. Visual shade determination using a reference scale (3D-Master Toothguide (3DM_TG), VITA Zahnfabrik, Bad Säckingen, Germany), followed by a digital color determination using a spectrophotometer (VITA Easyshade V, (ES_V), VITA Zahnfabrik), was performed. Color deviation was calculated in the Lab* color space (ΔE00) and converted into CIELAB 2000. The results were evaluated using the Mann–Whitney U test and the Wilcoxon Rank Sum test (α = 0.05). Significant differences between visual and digital color determination were proven (p < 0.001). Visual color determination (3DM_TG) showed a mean deviation (ΔE00 ± 95%CI) of 6.49 ± 0.47. Digital color determination (ES_V) showed significantly lower mean deviations of ΔE00 of 1.44 ± 0.58. Digital tooth color measurement using a spectrophotometer was a more reliable tool for the color determination of 3D-printed teeth for inexperienced dentistry students.