Toothguide Training Box Research Articles

Accuracy of tooth color determination by dental students using daylight-calibrated dental operatory lighting sources

Statement of problemLighting conditions are an essential factor for accurately determining tooth color. However, the ideal lighting conditions for determining tooth shade are rarely met and are difficult to quantify. While the use of a standardized daylight lamp D55 can improve accuracy, its high cost limits its use in dental offices. The use of modern operatory treatment units for tooth color determination is promising, as they now allow for the adjustment of light source settings such as color temperature and intensity. However, studies are needed to determine whether they provide accurate color determination. PurposeThe purpose of this study was to assess the accuracy of visual tooth shade determinations under the adjusted light sources of 2 different dental treatment units in comparison with a standardized daylight lamp D55. Material and methodsDental treatment units from 2 manufacturers KaVoLUX 540 LED (LK) and LEDview Plus (LDS) were tested. The light sources of these units were adjusted to match daylight conditions. A daylight lamp (Dialite Color 7; Eickhorst & Co. KG) was used as a control (D55). A total of 49 participants (median age of 25 years, 30 women) underwent the Ishihara screening and received standardized training calibration. A total of 2205 clinical visual tooth shade determinations were performed with the Toothguide Training Box using the Vita 3D-Master shade guide under the 3 different lighting types. Each participant had 15 color determinations made under each of the 3 light settings. Color differences were analyzed by using the Kruskal-Wallis, Wilcoxon rank-sum, and chi-squared tests (α=.05). ResultsThe type of lighting used for tooth shade determination had no significant effect on the accuracy of selected shade based on the ΔE00 metric (P=.133). Perfect matches were achieved in 50.8% of the cases under LK, 49.8% under LDS, and 53.6% under D55 light, with no significant difference among percentages (P=.315). Although there was a significant difference in time elapsed for shade determination by light type (P=.004), this difference was not clinically relevant (20.8 seconds for LK, 23.9 seconds for LDS, 21.9 seconds for D55). ConclusionsThe accuracy of color determination for both examined dental operatory lamps was found to be comparable with that of the standard D55 daylight lamp when adjusted to specific settings.

Influence of viewing distance on visual color differentiation in vitro.

To investigate whether viewing distance influences the results of visual tooth color differentiation. A total of 65 students underwent both theoretical and practical training by a standardized lecture on the use of an internet learning module (Toothguide Trainer, VITA Zahnfabrik) and a standardized training program (Toothguide Training Box) for visual shade-taking. Each student matched 10 randomly selected shade tabs presented at different viewing distances (arm's length distance [AL, 70 cm] and AL/2 [35cm]) under lateral, non-glare lighting at a 45-degree angle with a color differentiation lamp. The results were recorded as to what extent the presented and selected tabs of the color determination matched. The overall median values of perceived color difference (ΔE) were 1.6 for AL/2 and 3.2 for AL, and these values were significantly different (P < .001). Within the limitations of this study, it was shown that the viewing distance had a significant influence on the color deviation in tooth color assessment. Therefore, a smaller viewing distance of 35 cm for shade determination is recommended.

Gender-Dependent Quality of Shade Matching of Dental Professionals and Students.

ObjectivesThe purpose of this study was to evaluate shade matching ability of dental professionals and students using the VITA 3D-Master shade guide.Materials and methodsA hundred and twenty participants have been assigned to one of four groups as follows: specialists in prosthodontics (SPs), residents in prosthodontics (RPs), dental technicians (DTs) and dental students (DSs). The Toothguide Training Box (TTB) was used to test the participants’ shade-matching ability based on using 3 exercises and a final test. The mistakes were recorded during the exercises and mistake ratios (MR) were calculated. Time, scores, and color difference values (ΔE) were recorded and calculated. The one-way ANOVA was used to analyze the differences, and multiple regression analyses were used to evaluate the relationship in mean MRs, time, score and ΔE values between the groups.ResultsMale participants needed significantly greater amount of time than females to complete the final test (P<0.05). Male SPs achieved a significantly lower percentage of mistake ratios in second exercise than RPs (P<0.05), needed significantly less time than DSs to complete the final test and achieved significantly higher scores than RPs (P<0.05). Female SPs assessed the highest and DSs and RPs the lowest color differences (P<0.05). The results obtained from the exercises and final tests highly affected the amount of estimated color difference in both male and female groups (by 78% and 76%, respectively).ConclusionsWithin the population tested, gender of the participants showed a significant impact on quality of shade matching of dental professionals and students.

The Influence of the Extent of Color-Vision Deficiency on Shade-Matching Ability.

ObjectiveTo evaluate the influence of the extent of color-vision deficiency on visual shade-matching ability.Materials and methodsSix groups were investigated: the control group (N = 68), the protan medium deficiency (PMED) group (N = 5), the protan strong deficiency (PSTD) group (N = 5), the deutan mild deficiency (DMID) group (N = 5), the deutan medium deficiency (DMED) group (N = 5) and the deutan strong deficiency (DSTD) group (N = 8). The color vision of the participants was evaluated monocularly using the Hardy-Rand-Rittler (HRR) test and on an HMC Anomaloskop MR (Rayleigh test). The final exam on a Toothguide Training Box consisted of 15 lightness–chroma–hue tasks. The color difference (∆E*ab) and the shade-matching score (Σ∆E*ab) were computed. The means and the standard deviations for the Σ∆E*ab were calculated. An independent t-test was used for statistical analyses of the data and a comparison of means (α = .05) for protan groups and a one-way analysis of variance (ANOVA) and a post-hoc Bonferroni test (α = .05) for deutan groups.ResultsThe PSTD group had a mean Σ∆E*ab of 63.38 ± 9.52, which means their selections were significantly worse in comparison to the PMED group (Σ∆E*ab = 47.62 ± 9.88, p = 0.033). The selections of the control group were significantly better in comparison to all groups with color-vision deficiency (control – PMED, p = 0.031; control – PSTD, p < 0.0001; control – DMED, p < 0.0001; control – DSTD, p < 0.0001), except in comparison with DMID group (p = 0.082). The comparisons between deutan groups were not significantly different (DMID – DMED, p = 0.352; DMID – DSTD, p = 0.323; DMED – DSTD, p = 1.000).ConclusionParticipants with strong protan color-vision deficiency are worse at shade matching than participants with medium protan color-vision deficiency.

Effect of Clinical Experience on the Shade Matching Accuracy in Different Dental Occupational Groups.

ObjectivesThe 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 methodsA 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 (ΔE) values for each shade were calculated from L*, a* and b* values. Differences in accuracy, mean ΔE values and mean error ΔE values between four different groups were examined.ResultsNo statistically significant differences were found between the groups regarding accuracy and mean ΔE 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 ΔE 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 ΔE values, DTs made errors with significantly less deviations compared to other groups (p<0.05).ConclusionsThis 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 ΔE values, DTs were more successful in shade matching than other participants.

Do Type 1 Diabetes Mellitus and Color-Vision Deficiencies Influence Shade-Matching Ability?

To evaluate the effect of color-vision deficiencies and type 1 diabetes mellitus (DM) on visual shade-matching ability. Four groups of participants were investigated: a control group (n = 68); a group with protanomalia (n = 10); a group with deuteranomalia (n = 19); and a group with type 1 DM (n = 13). Color vision was evaluated monocularly using the Ishihara test, Farnsworth-Munsell 100 hue (FM100H) test, Hardy Rand Rittler (HRR) test, and with an HMC Anomaloskop MR (Rayleigh and Moreland tests). The final exam was on a Toothguide Training Box (TTB) and consisted of 15 lightness-chroma-hue tasks. The color difference (ΔE*ab) and the shade-matching score (ΣΔE*ab) were computed, and the correct lightness (L*), chroma (C*), and hue (h*) selections were counted. The means and standard deviations for the ΣΔE*ab, ΔE*ab, L*, C*, h*, Ishihara, HRR, FM100H, and Rayleigh and Moreland tests were calculated. One-way analysis of variance (ANOVA) and post hoc Bonferroni test were used for statistical analyses and a comparison of means (α = .05). The data analyses were performed using SPSS 22.0 for Windows (IBM). The control group selected the shade tab on the TTB significantly better (ΣΔE*ab = 31.57 ± 13.50) than the group with protanomalia (ΣΔE*ab = 55.50 ± 12.36; P < .0001) and the group with deuteranomalia (ΣΔE*ab = 59.18 ± 16.35; P < .0001), but not significantly better than the group with type 1 DM (ΣΔE*ab = 39.43 ± 11.46; P = .368). The group with type 1 DM selected the shade tab on the TTB significantly better than the group with protanomalia (P = .038) and the group with deuteranomalia (P < .0001). Participants with color-vision deficiencies are less accurate at shade matching than the control group and the group with type 1 DM.

Learning Shade Differentiation Using Toothguide Trainer and Toothguide Training Box: A Longitudinal Study with Dental Students

The positive training effect achieved with the Toothguide Training Box (TTB) has been demonstrated in previous studies. The aim of this study was to investigate the training effect with the TTB at six and 12 months using standardized color tests. The study involved 101 dental students. The participants were divided into two study groups and one control group. Ten standard color samples were determined under uniform environmental conditions with VITA 3D-Master. The control group (N=30) took the color test after one week. Study group 1 (N=49) took the color test after six months and study group 2 (N=22) at 12 months for the first time by following the TTB curriculum. The control group achieved an average ΔEt1=0.85. In study group 1, the ΔEt2 was 2.29, and in study group 2, ΔEt3=2.25. The results after six and 12 months were highly significant compared to the control group (α=0.001). Dependence was determined only with regard to gender. In this study, the TTB quickly led to an improvement in tooth color differentiation among students. After six months, there was a decrease in the training effect. These results suggest that the TTB curriculum should be provided at the end of preclinical training.

Evaluating the ability of dental technician students and graduate dentists to match tooth color

The ability of dental technician students to match tooth shade with the Vita 3D-Master shade guide and Toothguide Training Box has not been investigated. The purpose of this study was to evaluate and compare the shade-matching ability of dental technician students and graduate dentists using the Vita 3D-Master shade guide. Twenty-nine dental technician students (DTS group) and 30 graduate dentists (GD group) participated in this study. The Toothguide Training Box (TTB) was used to train the participants and test their shade-matching abilities. Shade-matching ability was evaluated with 3 exercises and a final test, all of which are components of the TTB. The number of mistakes for each participant for value (L), chroma (c), and hue (h) were recorded during the exercises and the final test, and the mistake ratios were calculated. Color difference (ΔE) values for each shade were calculated from the L*, a*, and b* values of the Vita 3D-Master shade guide for each participant in both groups. The Mann-Whitney U test was used to determine statistically significant differences between the L, c, and h mistake ratios of the 2 groups, and the Student t test was used to determine statistically significant differences between the final test scores and the ΔE values of the groups (α=.05). The mistake ratio for L in the GD group was significantly higher than that of the DTS group (P<.05), whereas the mistake ratio for h in the DTS group was higher (P<.001). No significant differences were observed between the groups regarding the mistake ratios for c (P>.05). With regard to the final test scores and the ΔE values, no significant differences were found between the groups (P<.001), and the DTS group received higher scores than the GD group (912 and 851). The mean ΔE values for the DTS and GD groups were 1.72 and 2.92. DTSs made more mistakes in the h parameter than GDs, and GDs made more mistakes in the L parameter than DTSs. With regard to the final test scores and the ΔE values, DTSs were more successful in shade matching than GDs.

Randomized multi-centre study on the effect of training on tooth shade matching

ObjectivesThe aim of this study was to find out whether Toothguide Trainer, TT, and Toothguide Training Box, TTB, show any training effects, independent of the shade guide chosen. MethodsStudents from four dental schools (N=78) were included in this study. The participants were randomized into a study, 42 students (age range: 19–27 years; 69% female, 31% male) and a control group of 36 students (age range: 19–30 years; 57% female, 43% male). The study group started with a double blind introduction test, followed by the TT and TTB training, finishing with the final test. The control group only passed the introduction and – after a break – the final test. Eight randomly chosen samples, seven of the Vita classical and one of the 3D-Master colour scale, were marked by barcodes. Colour matching was arranged by the Vita classical scale. ResultsThe results of the pre- and final tests of both groups were combined. For every sample, the value ΔE was determined. The summation of all eight samples from the introduction and final tests offered a summarized ΔE value. The differences between introduction and final tests revealed the individual learning success. 47.6% of the study group showed statistically significant better results than the control group, 33% (p=0.031). ConclusionTT and TTB show a positive effect of training on tooth shade matching independent of the colour scale used. Clinical significanceVisual shade taking is the most frequent clinical method for shade determination. To increase better results in visual colour matching, TT and TTB training is used. This is the first study examining the training effect of TT and TTB using Vita classical scale.

Evaluation of two different approaches to learning shade matching in dentistry

Statement of the problem. An important aspect of dental education is teaching and learning shade matching. Objective. To assess the success of two different strategies for learning shade matching. Materials and methods. Seventy-one pre-clinical students (mean age 23; 33.3% men) were divided into two groups. One group (TTB) formed teams of two and they matched three pre-determined teeth on each other using the 3D-Master shade guide. After this exercise, they learned shade matching using a standardized device (Tooth Guide Training Box, TTB) by matching shade tabs in an artificial environment. The other group (GL) matched tooth color in a pre-defined clinical setting in groups of four students. After this, they matched the same teeth as before training, again in groups of two, similarly to group TTB. The reference tooth color was determined by two experienced prosthodontic clinicians. The L*a*b* values for the tabs were provided by the manufacturer and the color difference (ΔEab) between the chosen tab and the reference was calculated. Linear general estimation equation models were used for statistical evaluation (p = 0.05). Results. In the TTB group, the difference between ΔEab values before and after training was 0.03, which was not significant (p = 0.927; 95% CI: −0.70/0.77). In the GL group, ΔEab was 0.98 smaller after training, which was significant (p < 0.001; 95% CI: 0.50/1.50). Conclusion. The ability to match tooth color could be improved by using a group-learning approach in a clinical setting and implementation of such a training session should be considered in undergraduate and postgraduate dental education.

Toothguide Training Box for Dental Color Choice Training

The purpose of this study was to evaluate the use of the Toothguide Training Box (TTB) for training dental students in color identification. The seventy-four volunteers who took part in the study attended a seminar on the Vita 3D Master Guide (MG) and the TTB system as well as a demonstration of the equipment before training began. At the end of the training they took the TTB final test. In addition, the participants were asked to recognize ten MG shade tabs in a blind manner before and after TTB training. The training times and percentages of correct answers were compared using the paired t-test. Variations in scores with training times and percentages of correct answers before and after training were compared using the ANOVA test. Training times between thirty-one and thirty-eight minutes provided a significantly higher mean score than training times of over thirty-eight minutes (p=0.036). The percentage of correct answers obtained with the MG before and after training shows a positive correlation. High TTB scores are associated with a greater number of correct answers in MG shade tab selection.

The linear shade guide design of Vita 3D‐master performs as well as the original design of the Vita 3D‐master

Visual tooth colour assessment by use of the Vita 3D-Master(®) (3D; Vita Zahnfabrik, Bad Säckingen, Germany) is well documented. To improve handling, a new linear arrangement of the shade tabs has been introduced (LG; Linearguide 3D-Master(®) ). The purpose of this study was to investigate whether the linear design has an effect on shade matching. Fifty-six students underwent identical, theoretical and practical training, by use of an Internet learning module [Toothguide Training Software(®) (TT)] and a standardised training programme [Toothguide Training Box(®) (TTB)]. Each student then matched 30 randomly chosen shade tabs presented in an intra-oral setting by a standardised device [Toothguide Check Box(®) (TCB)]; 15 matches were made using the 3D and 15 using the LG shade guide system, under a daylight lamp (840 matches for each guide). It was recorded to what extent the presented and selected shade tabs, or the lightness group of the tabs, matched, also the needed time for colour matching. The results showed that 35% of perfect matches were observed for the 3D and 32% for the LG. The lightness group was correct in 59% of cases for 3D and 56% for LG. Mean time needed for matching of tabs and lightness group was no different between groups (no significant difference for any assessment). Within the limitations of the study design, the colour assessment with regard to performance and time needed in shade matching was not different with the LG or the 3D. Therefore, the user should choose which shade tab arrangement is more applicable.

Application and comparison of two shade guide training systems

To evaluate the effect of shade guide training box and shade guide training software on shade matching ability of observers when used separately. To find out the difference between two training plans when the two training methods were used in combination, and to provide information on shade matching training system. Sixty-two postgraduate dental students who specialized in prosthodontics with 1 to 5 year clinical experience were enrolled in this study. At base line, each participant were asked to match 7 standard shade tabs which have been randomly chosen from Vita 3D-Master shade guide and 7 intermediate shade tabs from Vita bleached guide 3D-Master. Then the subjects were allocated to 2 groups [Toothguide Training Box (TTB) group and Toothguide Training (TT) group] according to the baseline data. Participants in group TTB received training session once a week for 3 weeks, while those in group TT received TT training session once a week for 3 weeks. All participants took a middle term shade-matching test. Then the two groups exchange the training methods and repeat the whole process, a final test was given to each participant. The elapsed time and number of accurate shade matching were recorded for each training session. Wilcoxon signed ranks test and ANOVA were used in data analysis. There were no significant differences in the number of accurate shade matching (standard shade tab and the sum) between group TTB (4.4 +/- 1.3 and 5.3 +/- 1.6) and TT (4.0 +/- 1.4 and 4.9 +/- 1.5) in the middle term test with higher value found in group TTB. In the final test, the number of accurate shade matching (standard shade tab and the sum) in group TT (4.9 +/- 0.8 and 6.4 +/- 0.8) was higher than that in group TTB (4.7 +/- 1.1 and 5.8 +/- 0.9), but significant difference was found only when the sum number of accurate shade matching was compared between the two groups (P < 0.05). There was no significant difference between data from middle term test and from final test in group TTB; while in group TT, the number of accurate shade matching in the final test was significantly increased compared with that in the middle term test (P < 0.05). When used in combination, TT training followed by TTB training is recommended.

Does gender and experience influence shade matching quality?

Objectives To evaluate the influence of gender and level of experience on shade matching quality. Methods A study was simultaneously performed at 15 universities located in 9 countries. A total of 614 color normal participants completed all phases of the experiment. Among them, there were 305 females and 309 males, 319 dental students and 295 dental professionals. A lecture on color matching in dentistry was given to all participants. Initial training was performed using Toothguide Trainer software (TT), while Toothguide Training Box (TTB) was used for both training and testing of participants’ shade matching results. The test task was to successively match 15 shade guide tabs with the corresponding shade guide. The shade matching score for each participant was computed as a sum of color differences ( ∑ Δ E ab * score) between target tabs and selected tabs. Lower scores corresponded to better shade matching results and vice versa. Means and standard deviations were calculated. Mann–Whitney U test was used for statistical analysis of the data ( α = 0.05). Results The mean shade matching score (S.D.) for all participants was 41 (21). The score for female and male participants was 38 (20) and 44 (21), respectfully ( p < 0.001). The difference in scores between dental students, 42 (20), and dental professionals, 39 (21), was not statistically significant. Conclusion Within the limitations of this study, females achieved significantly better shade matching results than males, indicating that gender plays an important role in shade matching. The level of experience was not found to be significant factor in shade matching.