The objective of this study was to evaluate the intra-device repeatability and accuracy of dental shade-matching device (VITA Easyshade® Advance 4.0) using both in vitro and in vivo models. For the repeatability assessment, the in vivo model utilized shade-matching device to measure the central region of the labial surface of right maxillary central incisors of 10 people twice. The following tooth colors were measured: B1, A1, A2, A3, C1 and C3. The in vitro model included the same six Vitapan Classical tabs. Two measurements were made of the central region of each shade tab. For the accuracy assessment, each shade tab from 3 Vitapan Classical shade guides was measured once. CIE L*a*b* values were determined. Intraclass correlation coefficients (ICCs) were used to analyze the in vitro and in vivo intra-device repeatability of the shade-matching device. The difference between in vitro and in vivo models was analyzed. Accuracy of the device tested was calculated. The mean color differences for in vivo and in vitro models were 3.51 and 1.25 E units, respectively. The device repeatability ICCs for in vivo measurements ranged from 0.858 to 0.971 and for in vitro from 0.992 to 0.994. Accuracy of the device tested was 93.75%. Within the limitations of the experiment, VITA Easyshade®Advance 4.0 dental shade-matching device enabled reliable and accurate measurement. It can be a valuable tool for the determination of tooth colours.

The aim of this study was to evaluate and compare the translucency of two different all-ceramic systems using Vita Easyshade digital shade matching device in an in vitro model. Translucency of lithium disilicate glass-ceramic (IPS e.max Press) and zirconia all-ceramic system (Ceramill ZI) were evaluated and compared. A total of 5 square-shaped specimens with 0.5 mm thickness were fabricated from each ceramic system in A1 shade according to Vitapan Classical shade tab. Specimens were then veneered and glazed with corresponding veneer ceramics recommended by each system manufacturer and the total thickness was set to 1.5 mm. Translucency was evaluated using VITA Easyshade in two stages: before and after veneering and glazing on black and white background. Translucency parameter (TP) was calculated. A one-way ANOVA and Bonferonni tests were used when appropriate (α=0.05). Lithium disilicate glass-ceramic was significantly more translucent than the zirconia system in both stages (P<0.05). Translucency of all specimens was significantly decreased after veneering and glazing in both all-ceramic systems (P<0.05). The translucency of two different dental ceramics was significantly influenced by both material and stages of preparation. Within the limitations of the experiment, these results can be valuable and help the clinician to make appropriate esthetic decisions.

The purpose of this study was to evaluate and compare lightness (L), chroma (C) and hue (h), green-red (a) and blue-yellow (b) character of the color of maxillary right central incisors in different light conditions and light sources. Two examiners who were well trained in digital color evaluation participated in the research. Intraclass correlation coefficients (ICCs) were used to analyze intra- and interobserver reliability. The LCh and L*a*b* values were determined at 08.15 and at 10.00 in the morning under three different light conditions. Tooth color was assessed in 10 subjects using intraoral spectrophotometer VITA Easyshade Advance 4.0® set at the central region of the vestibular surface of the measured tooth. Intra- and interobserver ICC values were high for both examiners and ranged from 0.57 to 0.99. Statistically significant differences in LCh and L*a*b* values measured in different time of the day and certain light condition were not found (p>0.05). Statistically significant differences in LCh and L*a*b* values measured under three different light conditions were not found, too (p>0.05). VITA Easyshade Advance 4.0® is reliable enough for daily clinical work in order to assess tooth color during the fabrication of esthtic appliances because it is not dependent on light conditions and light sources.

Objectives: The aim of this study was to evaluate the effect of clinical experience level on the shade matching accuracy in different dental occupational groups. Materials and methods: A total of 80 participants, assigned to one of four groups depending on the level of their clinical experience in shade matching: dental technicians (DTs), residents in prosthodontics (RPs), specialists in prosthodontics (SPs) and dental students (DSs) took part in the study. They were asked to use Tooth guide Training Box (TTB) and determine 15 standardized shade tabs using VITA 3D-Master shade guide. The number of mistakes in final test for each participant was recorded and accuracy was calculated. Color difference (CE) values for each shade were calculated from L*, a* and b* values. Differences in accuracy, mean CE values and mean error CE values between four different groups were examined. Results: No statistically significant differences were found between the groups regarding accuracy and mean CE values (p> 0.05). The accuracy rate in four groups was 0.51 +/- 0.20 (DTs), 0,54 +/- 0.18 (RPs), 0.49 +/- 0.16 (SPs) and 0.55 +/- 0.14 (DSs), respectively. Mean CE values were 2.10 +/- 0.98 (DTs), 2.18 +/- 0.97 (RPs), 2.51 +/- 0.97 (SPs) and 2.08 +/- 0.86 (DSs), respectively. Regarding mean error CE values, DTs made errors with significantly less deviations compared to other groups (p< 0.05). Conclusions: This study has shown that clinical experience is not found to be a significant factor to the shade matching accuracy. With regard to the mean error CE values, DTs were more successful in shade matching than other participants.

The aim of this study was to evaluate the inter-observer reliability of dental shade-matching device using an in vivo model.Four observers who were well trained in color assessment and handling of the dental shade-matching device determined teeth color and CIE-Lab values on maxillary right central incisors in 10 patients with completely healthy and intact dentitions. VITA Easyshade® Advance 4.0 shade-matching device was utilized to measure the central region of the labial surface of all investigated teeth, twice by each observer. The inter-observer reliability of the measurements was observed and deviations between Lab and [Formula: see text]E values between the observers were calculated. Intraclass correlation coefficients (ICCs) were used to analyze inter-observer reliability.One-way ANOVA showed no statistically significant differences in color measurement of four observers in all the measured values (p>0.05). Delta E values ranged from 3.018 to 5.234. Although some small differences existed, statistically significant differences between the observers were not found (p>0.05). Inter-observer ICCs were very high for all observers (from 0.651 to 0.992).Inter-examiner reliability of measurements using VITA Easyshade® Advance 4.0 shade-matching device was acceptable. Apart from the digital equipment, a well trained observer seems to be crucial in order to achieve correct dental color measurement.