Vitapan Classical Research Articles

Color Differences of Polimerized Resin-Based Composites and Corresponding Shade Guides

Objective: The purpose of this study is to analyze and compare the colors (A2, A3 and A3.5) of polymerized resin-based composites (RBCs) with respect to the shade numbers within each product line and the VITAPAN Classical® shade guide they purported to represent. Methods: Three A-shades (A2, A3 and A3.5) from four RBC products (Harmonize®, Empress® Direct®, Grandio® and Filtek® 500) were compared within the VITAPAN Classical® shade guide and within their own commercial shade guide. Nine disk-shaped specimens, 6 mm in diameter and 2 mm thick, were prepared for each RBC color (three of each color). The color measurements were made according to the CIE L*a*b* color scale (quantifying L*c*h*a*b* values) using a Vita Easyshade Compact IV® digital spectrophotometer. We calculated the CIEDE2000 color differences between polymerized composites and shade guides, as well as between composites. The values obtained from composites and samples of the color guides in the CIE L*a*b* space were represented by ICC3D software (Version 1.2.9) Results: The ANOVA test verified the existence of statistically significant differences between composites for the same shades (p < 0.05) except for shade A2. CIEDE2000 color differences between composites and the VITAPAN Classical® shade guide ranged from 3.5 to 13.1 depending on the composite and the shade. Conclusions: There were color differences among the polymerized resin-based composites, between these and their own shade guides/manufacturer’s commercial guides, and between the former and the corresponding samples of the VITAPAN Classical® shade guide. Clinical significance: Color selection when performing an aesthetic dental restoration is essential for the clinician and the patient to obtain an optimal result. Taking into account the color difference (∆E00) for each composite with the VITAPAN Classical® shade guide or with the manufacturers’ commercial guide allows for more precision with shade selection in aesthetic dentistry.

The effect of imposing apple (Malussylvestris Mill) juice on discoloration of nanofiller and nanohybrid composites

Composite resin can undergo discolouration if exposed to dyes. The use of apples can whiten teeth because they contain ma-lic acid. True experiment research with pretest-posttest with control group design using 24 samples divided into 6 treatments, namely sample groups 1 and 2 (nanofiller and nanohybrid composite groups that have been discoloured soaked in apple fruit juice (Malus sylvestris Mill) 80% concentration, groups 3 and 4 (negative control group, discoloured nanofiller and nanohy-brid composites soaked in distilled water) and groups 5 and 6 (positive control group, discoloured nanofiller and nanohybrid composites soaked in 10% carbamide peroxide). The colour change was determined with a shade guide (Vitapan Classical). The results were normally distributed and homogeneous. One-way Anova test showed there was a significant difference in each group. In the independent t-test, there was a significant difference in colour change between nanofiller and nanohybrid composite resins that experienced discoloration in 80% apple juice immersion. It was concluded that nanofiller composite resin had lower discolouration compared to nanohybrid.

THE EFFECT OF HIGH TEMPERATURE HEATING ON WEIGHT AND COLOR CHANGES IN COMPOSITE RESIN AS FORENSIC IDENTIFICATION

Background: Fire disaster is a non-natural disaster that often occurs. The impact is that victims are difficult to identify. One of the identification methods that can be used is dental restorative materials with observing changes in color and weight that occur in dental restorative materials due to exposure to high temperatures. Composite resin is a dental restorative material that is often used because it has good aesthetics, physical and mechanical properties. Purpose: This study to determine the effect of high temperature on weight and color changes in nanohybrid and bulkfill composite resin as a reference for forensic identification. Method: This research is an experimental laboratory with a pre and post-test control group design. A total of 30 nanohybrid composite resin samples and 30 bulkfill composite resin samples were divided into 5 groups consisting of 4 treatment groups and 1 control group. The treatment group was heated at four temperature groups, 30°C-200°C, 30°C- 400°C, 30°C-800°C and 30°C-1100°C using a furnace (Thermo Scientific, USA). Weight changes were measured using a digital scale (Ohaus,China) and color changes were observed using the Shade Guide (Vitapan Classical, Germany). Result: A change in color and weight of the nanohybrid composite resin and bulkfill after being heated at high temperatures. Two-Way ANOVA test and Post Hoc LSD test showed that there was a significant difference in weight between nanohybrid composite resin and bulk fill composite resin at each temperature interval (p<0.001). Conclusions: High temperature heating affects the color and weight changes of nanohybrid and bulkfill composite resin. Keywords: Bulkfill composite resin, High temperature heating, Nanohybrid composite resin

THE EFFECTS OF HIGH TEMPERATURE HEATING ON COLOUR AND WEIGHT CHANGES IN GIC AND RMGIC (A STUDY TO SUPPORT IDENTIFICATION OF FIRE VICTIMS)

Background: The temperature reached by fire disaster was varies. The disaster can cause fatalities and thus human identification is required. Dental restorative materials have properties that are resistant to high temperatures and play a role in identification process of fire victims. The identification process can be observed from the change in colour and weight of the restorative material. GIC and RMGIC are some of the most commonly used restorative material because they have good aesthetics properties, biocompatible, economical, and can release fluoride. Purpose: To determine the effect of high temperature heating on colour and weight changes in GIC and RMGIC as a support for forensic identification. Method: A total of 30 GIC and RMGIC samples used in this study were made in the form of cylinder with a size 3x2 mm. Each material was heated at four temperature groups of 30°C-200°C, 30°C-400°C, 30°C-800°C dan 30°C-1100°C using a furnace. The study was continued with the examination of colour using the Vitapan Classical Shade Guide and weight changes using a digital scale. Results: GIC and RMGIC experienced changes in colour and weight changes due to hight temperatures of 30°C-200°C, 30°C-400°C, 30°C-800°C dan 30°C-1100°C. High temperature heating shows the difference of each material. This is indicated by the p value <0,001 in the Two Way Anova Test and Post Hoc LSD which means that there is a significant difference in weight difference between GIC and RMGIC at each temperature interval. Conclusion: High temperature heating affects the colour and weight changes of GIC and RMGIC. Keywords: Forensic identification, GIC, High temperature heating, RMGIC

Effect of ocular dominance, clinical experience, and sex on the accuracy of shade selection.

The study aimed to evaluate the influence of ocular dominance, clinical experience, and sex on the accuracy of visual color matching. A total of 104 selected participants consisting of dental students and dental practitioners were allocated into two groups based on their clinical experience of using visual shade matching tabs for the selection of tooth shade. Both the inexperienced (IXP), as well as experienced participants (EXP), were then asked to correctly match the shades of five tabs (A2, A3.5, B1, C2, and D3) of a commonly used visual shade guide (Vitapan Classical shade guide, VITA Zahnfabrik) that were kept constant throughout the study. The participants documented the shade of those tabs using another set of shade guide using the right eye (left eye covered), left eye (right eye covered), as well as both eyes. Test for ocular dominance was performed using the Dolman method. The results were statistically analyzed using the chi-square test with a level of significance set at < .05. The percentage of correct shade matching with the monocular dominant vision (53%) was significantly better as compared to the monocular non-dominant vision (12%) (P < .001) or binocular vision (44%) (P < .05). Sex had an influence in shade selection (P = .031). However, clinical experience was an insignificant aspect in shade matching (P = .078). Knowing the clinician's dominant eye can be clinically relevant, as it can influence the accuracy of shade selection, irrespective of sex and clinical experience.

An analysis of an educational method to improve the shade-matching ability of dental students

Statement of problemThe predoctoral dental curriculum includes didactic lectures, demonstrations, and training on shade-matching techniques and protocols. However, a significant percentage of esthetic failures are still observed clinically. An assessment is required to determine whether reevaluation and modification of this training protocol would help future dental practitioners better perceive and communicate the dental shade. PurposeThe purpose of this study was to evaluate dental students’ knowledge of and skill in shade selection and effective prescription writing before and after educational training with 3 different shade guides. Material and methodsThirty predoctoral dental students (interns) who had completed their academic program and were undergoing clinical training were selected. After excluding color vision deficiency, the study participants were first asked to evaluate the shade of the right maxillary central incisor of 5 patient participants by using 3 different shade guides (Vitapan Classical, Vitapan 3D-MASTER, Chromascop) under standardized conditions. They were then asked to write an esthetic prescription, communicating the shade to a dental laboratory technician. A dental faculty member evaluated the baseline control shade for each participant, and a standardized prescription format was written. This was used as a reference by a dental laboratory technician to score the intern’s prescription as clear, unclear, poor, or illegible. After the assessment, focused small group learning with lectures, clinical demonstrations, and case-based discussion was provided to the interns on shade assessment over 10 to 15 days. All the interns were reassessed for their visual shade perception and prescription writing after a month’s interval. The mean percentage agreement, mean percentage shade match, and mean color difference between the shade selected and the control shade for each of the 5 participants, with all 3 shade guides, were evaluated along with the prescription scoring before and after the educational training. Statistical comparison of before and after values were made by using the paired-sample z-test for percentage agreement versus disagreement among the interns for the shade selected, paired t test for mean percentage agreement, mean percentage shade match, and mean color difference. The repeated measure ANOVA test was used for the prescription scorings (α=.05). ResultsA significant difference in prescription scoring (P<.001) was observed. A significant difference in the percentage shade match (P<.01) for all 3 shade guides and mean percentage agreement for Chromascop and Vita 3D-MASTER (P<.05) were observed. A nonsignificant mean color difference between the shade selected by the intern and the baseline shade was observed. ConclusionsA significant difference in prescription scoring was observed after training, along with a higher percentage shade match and percentage agreement. This indicated a need to reconsider the educational training provided for dental shade assessment and communication and to implement better protocols in the dental curriculum.

Management of Non-Vital Teeth Discoloration with the Internal Bleaching : A Case Report

Tooth discoloration due to intra coronal bleeding after trauma can cause aesthetic disturbances andappearance. Internal bleaching is a non-invasive method to restore tooth color which is performed afterendodontic treatment by placing a strong oxidizing agent in the pulp chamber. Aim of this study was toreport the success of internal bleaching procedure to restore discolored teeth due to trauma. A 44-year-oldfemale came to Conservative Dentistry Universitas Airlangga with chief complaint of the upper right insisortooth looks darker than the adjacent teeth. The patient had fallen 10 years ago from her motorcycle and hertooth had been painful and then the pain disappeared. In intra oral clinical examination, it showed that tooth11 had discoloured, vitality test of tooth 11 showed no response to electric pulp test. Radiographic viewshowed that radiolucen in periapical area and no fracture was found. At the first visit, treatment of singlevisit root canal using rotary instrument and gave dressing calcium hydroxide. A week later on the secondvisit, internal bleaching with hydrogen peroxide 35% was done. After bleaching, calcium hydroxide wasapplied to neutralize the oxidizing agent and then re-evaluated for the color. At the third visit, it showed thatthe tooth colour was obtain as desire from C3 to A3 (Vitapan Classical). The internal bleaching procedureon the traumatized tooth was the best option to restore the function and aesthetics according to the originaltooth colour and also provided benefits in terms of saving time, lower price, and maximum results.

Spectrophotometric evaluation of restorative composite shades and their match with a classical shade guide.

ObjectivesThe aim of this study was to verify the match between 5 shades of composites from different manufacturers with a shade guide and among the systems using a portable spectrophotometer.Materials and MethodsShade measurements were performed on specimens of Z350 XT (3M ESPE), Charisma Diamond (Heraeus Kulzer GmbH), Esthet X-HD (Dentsply Caulk), and Empress Direct (Ivoclar-Vivadent) for shades A1, A2, A3, B1, and C3 using a Vita Easyshade spectrophotometer (Vita Zahnfabrik) against a white background. Corresponding shades of Vitapan Classical (Vita Zahnfabrik) guide were measured likewise and shade variation (ΔE) was calculated based on International Commission on Illumination L*a*b* parameters. The ΔE of the composites in each shade was compared by one-way analysis of variance and Tukey's post hoc test (α = 0.05).ResultsAll composites presented ΔE > 3.7 compared with the shade guide. Variation in shades A3, B1, and C3 was significantly different for all composites. ΔE of Z350 XT was significantly lower for A1 than for the other shades, whereas ΔE of Z350 XT and Charisma Diamond were significantly lower for A2 than for the other shades.ConclusionsNo composite shade matched with the shade guide. Equivalent shades of the restorative composite from different manufacturers may show clinically noticeable ΔE.

Color comparison of three layered resin composite systems with three shade guides.

To investigate the color difference using both ΔE*ab and CIEDE2000 formulas of all combinations of all enamel and dentin shades of three different composite systems with three different shade guides, to compare the coverage error (CE) of the shade guides for each composite and to investigate whether coverage error is affected by enamel shade layer thickness (0.5 vs 1 mm). Disk specimens from all enamel and dentin shades of Essentia, Enamel Plus HRi, and IPS Empress Direct composites were fabricated. Color measurements were performed for all enamel-dentin combinations and for two thicknesses per enamel shade: 0.5 and 1 mm. Color was measured for three shade guides: Vitapan Classical, 3DMaster, and Ivoclar. Minimum color difference between layered composites and shade tabs, closest shade tab match and CE of all shade guides were calculated for all composite shade combinations. In most cases, the closest match was a mismatch. CE of 3DMaster was significantly lower for IPS Empress Direct and Enamel Plus HRi at 0.5 mm enamel thickness. Shade guides exhibited higher lightness values compared to composites and composites lower chroma values compared to shade guides. Shade guides do not match well to the layered composites. 3DMaster performed better than the other two shade guides, in most cases.

Tooth Shade and Skin Colour: A Descriptive Cross-Sectional Study

Selection of proper tooth shade is one of the most significant factors influencing patients' aesthetic perception and improved prosthesis acceptance. Guidelines in the dental literature suggest age, sex, colour of skin, hair and eye for selecting tooth shade when past records cannot be obtained. The objective of the study was to find out the prevalence of the most common tooth shade in relation to the skin colour and the prevalence of the same in relation to age and sex. A descriptive cross-sectional study was carried out at Kathmandu Medical College from June to August 2019. Vitapan Classical Shade guide was used to select the shade of upper right central incisor in 338 participants. Revlon Foundation Makeup Shade guide was used to determine colour of skin. Participants were examined without facial makeup. Skin colour and teeth shade were examined in daylight at about the same time of the day. Data obtained were computed and analysed using Microsoft Excel 2016 software. Prevalence of tooth shade with high value (lighter shade) was seen in all fair 121 (35.8%), medium 63 (18.6%) and dark skin tones 23 (6.8%). Most common teeth shade in fair individuals was B1 47 (37.9%), in medium also B1 25 (7.4%) and dark was B2 9 (2.7%). Age range of 10 to 35 years had tooth shade with higher value 159 (47.04%). Hence, teeth shade with high value (lighter shade) was prevalent in skin tone of all types in current study. Skin tone was not related to teeth shade selection, teeth became darker with age and females had lighter teeth shade (high value).

Effects of different light sources on tooth shade selection.

Differences in lighting conditions can make matching the shade of a single porcelain tooth to the natural adjacent teeth very challenging. The purpose of the study was to examine visual shade selection under 3 different light sources - natural daylight, a dental operating light and a color-corrected light. The visual assessment was based on a comparison between a shade guide and the target tooth. One observer with normal color vision was asked to visually match the color of the maxillary central right incisor and the maxillary right canine in a group of 100 subjects, aged 22-40 years. Two shade guides were used - VITA Vitapan Classical® and VITA 3D Master® - in natural daylight as well as under an operating light and a handheld light (Demetron Shade Light®). The VITA Easyshade® spectrophotometer was used to evaluate the results of the visual shade selection method. Significant differences were found between the effects of using the shade guide systems (p < 0.05) and light sources (p < 0.05). Overall, the use of the Vitapan Classical shade guide significantly improved the correlation between visual matching and the spectrophotometer readings. Within the limitations of this study, the Vitapan Classical shade guide demonstrated superior agreement in shade selection as compared to the 3D Master shade guide. The Demetron Shade Light was proven to be a useful device for the color matching of artificial teeth in prosthodontic treatment. Visual tooth color matching is a subjective method and it produces the best results under a color-matching light.

Analysis of colorimetric parameters of international commission on illumination L*a*b* system in the color of maxillary central incisors

Introduction. Tooth color can be represented in a three-dimensional color system by applying L* (lightness), a* (red-green color tone) and b* (yellow-blue color tone) coordinates. Clinically significant color difference, Delta-E, can be expressed in units that are correlated with visual perception using the International Commission on Illumination L*a*b* system. The aim of the study was spectrophotometric analysis of the natural maxillary central incisor color, and to establish any gender-related differences in lightness, red-green tone, and yellow-blue tone coordinates. Material and Methods. The study included 80 students (40 male and 40 female, with an average age of 22 years). The color of the maxillary right central incisor was determined using an intraoral spectrophotometer and VITAPAN Classical and VITA 3D-Master color shade guides. Lightness, red-green tone, and yellow-blue tone values were recorded for each result. The obtained data were processed by using ?2, Student?s t-test and Mann-Whitney test. Results. Results showed no statistically significant gender-related difference in color according to the VITApan Classical and VITA 3D-Master color key. No difference was found in the lightness of the central maxillary incisor between genders, or in terms of red-green tone (p = 0.860573). A statistically significant difference was found when observing the sex-related yellow-blue tone of the color of the central maxillary incisor. Conclusion. The analysis of colorimetric parameters of the International Commission on Illumination L*a*b* system provides useful information about the tooth color in the examined population, while potentially revealing differences in lightness, red-green tone and yellow-blue tone between genders.

Dental students' tooth shade selection ability in relation to years of dental education.

Background and Objectives:Perfect tooth shade selection is indispensable for successful esthetic dental restorations. Shade matching is a complex and multidimensional process that involves the cognitive ability of students. Hence, the aim of the present study was to assess and compare the shade matching ability of undergraduate dental students in various years of dental education.Methods:A cross-sectional study was conducted among 150 students enrolled in all five class years of the Bachelor of Dental Surgery course in a dental college in India. Each enrolled participant was presented with two exercises to assess shade matching ability. In the first exercise, basic shade matching ability of the students was assessed by a shade tab matching in a bench setting using Vitapan Classical shade guide. In the second exercise, the participants were asked to perform intraoral tooth color matching to evaluate their ability of shade matching in a clinical setup. Data was analyzed using SPSS version 21 and descriptive statistics were applied. Chi-square test was applied to find out significant differences among years of education.Results:For Exercise 1, 53 participants (35.30%) showed fair color matching ability in bench setting, 26.70% (n = 40) showed good ability, 22.70% (n = 34) demonstrated an excellent ability, whereas 15.30% (n = 23) had a poor ability of color matching. For Exercise 2, where clinical color matching ability of the students was analyzed, 34% (n = 51) obtained fair scores, 33.30% (n = 50) obtained good scores, 26% (n = 39) obtained excellent scores, whereas 6.70% (n = 10) of the participants had poor scores.Conclusion:This study showed that the clinical performance of dental students for shade matching improved as the years of dental education increased. Also, better outcomes were seen in clinical setting as compared to in vitro conditions.

The effect of ceramic thickness and resin cement shades on the color matching of ceramic veneers in discolored teeth

The objective of this study was to analyze the effects of ceramic material thickness and resin cement shade on the color matching of ceramic veneers at the gray tooth structures. Seventy-two artificial maxillary right central incisor teeth (C2 shade) were prepared according to veneer tooth preparation in practice. Ceramic materials (LT, A2 shade, IPS e.max Press) were selected to fabricate the 0.50- and 0.75-mm thick veneers at the body region. The ceramic veneer specimens were bonded to the artificial teeth by the 6 shades of resin cements (Variolink Veneer: shades of HV+3, LV-2, LV-3; and RelyXTM Veneer: shades of WO, TR, A3). A clinical spectrophotometer (Crystaleye, Olympus) was used to measure the color parameters. The color differences (ΔE values) of ceramic veneers and A2 shade tab (Vitapan Classical, Vita) and C* ab values were calculated. The results of three-way ANOVA indicated that the ΔE values of ceramic veneer and A2 shade tab were significantly different in the thickness of ceramic materials, shades of resin cements, and measuring regions (p<0.001). There were significant differences in 0.50-mm-thick ceramic veneers that exhibited higher ΔE values compared with veneers that were 0.75-mm thick. Tukey's HSD test showed that the average ΔE values in body region were significantly smaller than that in cervical and incisal regions. The color matching of ceramic veneers was significantly influenced not only by the ceramic thickness and the resin cement shades but also the tooth regions.

Translucency and color match with a shade guide of esthetic brackets with the aid of a spectroradiometer

ABSTRACTObjective: Since the color of esthetic brackets should match that of teeth, the aims of this study were to determine the color and translucency of esthetic brackets by means of the clinically relevant use of a spectroradiometer, and to compare the color of brackets with that of a commercial shade guide. Methods: The color of central and tie-wing regions of four plastic and four ceramic brackets was measured according to the CIE L*a*b* color scale over white and black backgrounds. Brackets were classified into five groups based on their composition. The color of Vitapan Classical Shade Guide tabs was also measured. Translucency parameter (TP) and contrast ratio (CR) were calculated to determine translucency. Results: Color differences between brackets and the shade guide tabs were 10.4 - 34.5 ∆E*ab units. TP and CR values for the central region were 16.4 - 27.7 and 0.38 - 0.58, whereas for the tie-wings they were 24.0 - 39.9 and 0.25 - 0.45, respectively. The color coordinates, TP and CR values were significantly influenced by bracket composition and brand (p < 0.05). Conclusions: Esthetic brackets investigated herein showed unacceptable color differences (∆E*ab > 5.5) compared with the shade guide tabs. Differences in the translucency of brackets by brand were within the visually perceptible range (∆CR > 0.07). Therefore, brackets showing the best matching performance for each case should be selected considering esthetic and functional demands.

The Influence of Dental Shade Guides and Experience on the Accuracy of Shade Matching.

There is limited and inconsistent information on some factors affecting visual shade selection. The aim of this study was to evaluate the influence of shade guide type and professional experience on shade-matching results. Thirty Dental students (DS), 30 General dentists (GDs) and 30 Dental specialists (S) participated in this study. The participants were asked to match six target tabs using two dental shade guides: Vitapan Classical (VC) and Vitapan 3D-Master (3D). An intraoral spectrophotometer was used for color measurement of target tabs and selected tabs. The color difference (ΔE) values between the target tab and selected tab were calculated. Data were analyzed using analysis of variance (ANOVA) and paired f-test (α = 0.05). Results of the first five best matches for each target tab were expressed as ΔE1 to ΔE5. Differences in the mean values of ΔE1 to ΔE5 between VC and 3D were compared using descriptive statistics. There were no significant differences among the three participating groups in ΔE values when the 3D was used (p = 0.389). However, significant differences were found with VC (p < 0.001). The ΔE values achieved from the 3D were significantly lower than those from VC for DS and S (p = 0.001 and p < 0.001, respectively). For each of the first five best matches, the mean ΔE values from the 3D were smaller than the corresponding values of VC. The type of dental shade guide affected the shade-matching results. The level of experience was not found to be an influential factor in shade matching when 3D-Master shade guide was used. Compared with Vitapan Classical shade guide, use of the Vitapan 3D-Master shade guide improves shade-matching results. Color, Experience, Gender, Selection, Shade, Visual. How to cite this article: Nakhaei M, Ghanbarzadeh J, Amirinejad S, Alavi S, Rajatihaghi H. The Influence of Dental Shade Guides and Experience on the Accuracy of Shade Matching. J Contemp Dent Pract 2016;17(1):22-26. Source of support: This study was supported by a grant (No. 920903) from the Vice Chancellor for Research of Mashhad University of Medical Sciences. The results presented here are based on undergraduate thesis (No. 2686) submitted to Mashhad School of Dentistry and Dental Research Center. None.

Comparison of Shade Match Compatibility between Vitapan Classical and 3D Master Shade Guide Systems by Dental Students in Tabriz Faculty of Dentistry

Background and Aims: Dentists perform color-match process during indirect and direct restorations. Color research has shown that shade guides do not always match the color of natural teeth. Moreover, visual evaluation of dental colors has been found to be inconsistent and unreliable. In fact, it has always been important when using different shade guides. Our purpose in this study was to compare shade selection using two shade guide systems of Vitapan Classical and 3D Master by dental students of Tabriz University of Medical Sciences. Materials and methods: In this analytical, cross-sectional descriptive study, 20 male and 20 female senior dental students with a little clinical experience in working with shade guides were selected. Each student used two shade guides (Vitapan Classical and 3D Master) separately for shade matching. Shade selection was randomly repeated one week later by the same protocol. T - test was used to compare repeatability of color matching (α=0.05). Comparison of the repeatability percentage was done with t-test. Results: Comparison of repeatability percentages of shade matching irrespective of gender showed that percentage of repeatability of shade match in 3D Master system was significantly high (P=0.00). In addition comparison of repeatability means of shade match with different shade guide systems on the basis of gender showed no significant differences (P=0.68). Conclusion: In general, the repeatability percentages of shade matching in 3D Master system was high and shade matching in females with this system was not different than males. Key words: Color vision; indirect restorations; dental students

In Vitro Evaluation and Comparison of the Translucency of Two Different All-Ceramic Systems.

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.

In Vivo and in Vitro Evaluations of Repeatability and Accuracy of VITA Easyshade® Advance 4.0 Dental Shade-Matching Device.

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.

Spectrophotometric color evaluation of permanent incisors, canines and molars. A cross-sectional clinical study.

Background and aimsAn accurate color reproduction represents the final validation level of an esthetic anterior or posterior restoration. The aim of this study was to evaluate the color of permanent maxillary incisors, canines and molars, using a clinical spectrophotometer.MethodsThe Vita Easyshade Advance 4.0® intraoral spectrophotometer was used by one clinician to determine the color of 369 permanent maxillary incisors, canines and molars. The best matches to Vitapan Classical® and 3D-Master® shade guides were recorded. A one-way analysis of variance and Kruskal-Wallis test were used to compare L*, a*, b*, c* and h* color coordinates among the 3 types of teeth. Differences between the mean values of all color coordinates were evaluated by use of Bonferroni corrections. Color difference (ΔE*) between incisors, canines and molars was calculated from ΔL*, Δa* and Δb* data and the results were compared to ΔE*=3.3 acceptability threshold.ResultsExcept for Δa* and Δh* between canines and molars, statistically significant differences among the mean differences of all color coordinates were found when the 3 types of teeth were compared by pairs. The most frequently measured shades were A1 (48.4%), respectively 1M1 (31.5%) for incisors, B3 (36.6%), respectively 2M3 (39.8%) for canines and B3 (44.7%), respectively 2M3 (52%) for molars. Incisors had the highest lightness values, followed by canines and molars. Molars were the most chromatic with the highest a* and b* values.ConclusionsDespite the limitations of this study, color differences among incisors, canines and molars were found to be statistically significant, above the clinical acceptability threshold established. In conclusion, successful esthetic restorations of permanent teeth of the same patient need an individual color assessment and reproduction of every type of tooth.