Shade Determination Research Articles

Evaluation of the effectiveness of cold-light whitening technique on tetracycline pigmentation teeth and aged extrinsic stain teeth

To evaluate the clinical effectiveness of cold-light whitening technique on tetracycline pigmentation teeth and aged extrinsic stain teeth. One hundred and fifty-two cases bleached by cold-light whitening technique were included in this study. The patients' teeth were divided into 3 groups: aged extrinsic stain teeth, mild tetracycline pigmentation teeth and moderate tetracycline pigmentation teeth. Visual determination of shade and Olympus crystaleye spectrophotometer were used to measure the tooth discoloration after bleaching. SPSS17.0 software package was used for statistical analysis. Visual determination showed that the efficiency of aged extrinsic stain teeth was significantly higher than that of mild and moderate tetracycline teeth group (P<0.05). Colorimetric method showed that the △E of moderate tetracycline teeth was significantly lower than aged extrinsic teeth and mild tetracycline teeth (P<0.05) . The △E of cervix changed more significantly than that of central and incisal edge in both mild and moderate tetracycline teeth group (P<0.05). The effect of cold-light whitening technique on aged extrinsic stain teeth is better than that of the tetracycline pigmentation teeth. Cold-light whitening technique can improve pigmentation of tetracycline teeth cervix．.

Influence of tongue position on the determination of tooth shade

Statement of problemDentists frequently use electronic devices to determine tooth color. However, neither the instructions for these devices nor the accompanying brochures refer to the environmental conditions required at the point of measurement. PurposeThe purpose of this multicenter prospective clinical study was to reveal whether a change in the oral background influences tooth color determination. Material and methodsStudents (N=42) at the dental clinic in Berlin, Leipzig, Greifswald and Olomouc (women n=27, men n=15) participated in this study. It was their first contact with the spectral photometer (Easyshade Advance 4.0; VITA Zahnfabrik). After a short introduction on how to use the device, the students made 1-point measurements on the same patient on the maxillary central incisor. In the first measurement, the patient's mouth was open, and the palatal surface uncovered. In the second measurement, the patient's mouth was closed slightly, and the tongue pressed on the lingual surface of the maxillary central incisor. The mean ±SD and the 95% confidence interval (95 % CI) were calculated using the Student t test for each test series (α=.05). ResultsStatistical evaluation of the 2 measurements revealed changes in the L*a*b* values with a mean L*=0.204, a*=-0.351, and b*=0.02; a median of 0.4, -0.3, and -0.1, respectively; a ±SD of 2.37, 0.64, and 0.89, respectively; and 95% CIs of L*=-0.476 to 0.884, a*=-0.531 to -0.702, and b*=-0.23 to 0.52, respectively. These differences were not statistically significant (P>.05). The measurements of L*, a*, and b* with and without tongue coverage of the lingual surfaces of the maxillary teeth did not show any statistically significant differences (P=.663). ConclusionsThe results demonstrate that the position of the tongue does not influence measurement accuracy during the application of the Easyshade Advance device.

The Implementation of Elaborative Feedback for Qualitative Improvement of Shade Matching-A Randomized Study

The objective of this prospective learning research study is to examine the impact of structured elaborative feedback in practical skills teaching of visual and digital shade matching. A total of 60 preclinical dental students participated in the study. The mean average age was 23 years, of which 37 were female (61.7%) and 23 male (38.3%). The participants were randomly divided into a study and control group (n = 30 each). Recording of shade matching was carried out on the phantom patient using clinically simulated settings with elaborative feedback in the study group (T1). Nine items were recorded for visual shade matching and six items for digital shade-taking. The errors were coded. The lower the total (max. 30 points), the fewer the errors made by students during shade determination. The subject labeled the tooth color using VITA 3D-Master and VITA Easyshade (Vita Zahnfabrik, Bad Säckingen, Germany). On comparing the two groups, the study group and the control group showed a similar mean error value at reference time T1. After intervention (T2) it was possible to achieve a clear improvement in the rate of errors for study group. In the study group there was a significant difference between the ΔE values from time T1 and T2 of visual shade matching (p <0.05). The digital ΔE values show in total no significant changes. Elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. Correctly determining the tooth shade is an essential treatment step in esthetic reconstructive dentistry. Color is probably one of the most important determinants of esthetics in dentistry. Factors such as lighting conditions, gender, age, experience, and color vision impairment affect the process of shade matching. With an elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. (J Esthet Restor Dent 28:277-286, 2016).

Development and implementation of the Clinical Tooth Shade Differentiation Course--an evaluation over 3 years.

Objective: Tooth shade differentiation concerns the identification and classification of tooth shades. The objective of this project was to implement the Clinical Tooth Shade Differentiation Course in the preclinical stage of studies and to evaluate the students' perspective over a period of 3 years.Methodology: The course is planned for a duration of 10 weeks with two 45-minute sessions per semester week. The entire attendance time was 10:15 h. 2 lectures of 90 minutes each, 2 seminars of 60 min each and 2 teaching units with the phantom head and role playing took place. In addition to the various parameters of tooth shade, changes in tooth shade and the basics of dental esthetics, clinical procedures for manual and digital tooth shade determination were explained and practiced. 96% (69 of 72) of the students participated in the first evaluation in 2012/2013 (T1), and 68% of these were women. In the following year, 2013/2014 (T2), 92% (45 of 48 students) took part; 62% of these were women and 38% men. The 2014/2015 evaluation (T3) comprised 94% (45 of 48 students). Of these, 67% were women.Results: In the evaluation, the students gave the course a positive grade. The questions in "General/Organization" were given a mean (M) of 1.5 (SD=0.7) in T1 and T2 , and 1.2 (SD=0.3) in T3. The "Overall Assessment" yielded MT1=1.6 (SD=0.6), MT2=1.5 (SD=0.5) and MT3=1.1 (SD=0.3). In T1 and T2, the item "The instructor actively involved the students in the course" was given a mean of 2.1 (SD=0.9), and in T3 a mean of 1.2 (SD=0.5). Conclusions: The course presented here conceptually shows how practical dental skills can be taught in a theoretical and clinical context. Educational objectives from the role of a dental expert were taken from the national competence-based catalog of educational objectives for dentistry and can also be supplemented. The objectives can be transferred to other dental faculties.

Visual and instrumental shade matching using CIELAB and CIEDE2000 color difference formulas

ObjectivesTo compare visual and instrumental shade matching performances using two shade guides and three color difference formulas. MethodsOne hundred dental students (DS) volunteers (35 males and 65 females) with normal color vision participated in the study. The spectral reflectance of 4 extracted human upper central incisors (UCI) and shade tabs from Vita Classical (VC) and Vita Toothguide 3D-Master (3D) shade guides were measured using a spectroradiometer (SP) under D65 illuminant (diffuse/0° geometry) inside a viewing booth with a gray background. Color coordinates (CIE L*, a*, b*, C* and h°) were calculated according to CIE D65 illuminant and CIE 2° Standard Observer. Color coordinates of UCI were also evaluated using a dental spectrophotometer (EA – Easyshade Advance). DS used VC and 3D to visually select the best shade match for each UCI, under same experimental conditions used for the SP evaluation. Three color difference metrics (CIELAB, CIEDE2000(1:1:1) and CIEDE2000(2:1:1)) were used to calculate the best instrumental shade matching based on minimum color difference. ResultsThe agreement between visual and instrumental shade matching was greater using SP (25–75%) than EA (0–25%). The percentage of best match for the visual assessment was more consistent using VC (23–55%) than 3D (19–34%). Considering the best performance (using SP and VC), the CIEDE2000(2:1:1) color difference formula showed the best estimate to the visual perception from DS. SignificanceWithin the limitations of this study, combining the use of SP, CIEDE2000(2:1:1) and Vita Classical shade guide most closely represented the visual perception of DS. Instrumental shade determination should be accompanied by experienced human visual assessment.

In vitro comparison of instrumental and visual tooth shade determination under different illuminants

Statement of problemWhile a considerable body of literature deals with the comparison between visual and instrumental tooth color determination, in most of these studies either the number of color specimens or the number of examiners is too small to allow for a general statement about such a subjective method as visual color determination. Furthermore, perceptual aspects like perceptible or acceptable color differences are often not considered. PurposeThe purpose of this study was to investigate the precision of a spectrophotometer in tooth shade determination compared with visual color matching using a shade guide in vitro. Moreover, the influence of different illuminants as well as of sex and professional experience of the examiners on visual color matching was analyzed. Material and methodsFifty examiners (13 men, 37 women; without dyschromatopsia), grouped by professional experience, determined the shades of 10 prosthetic teeth with the Vitapan classical shade guide under 4 illuminants (daylight, halogen, fluorescent [5000 K], fluorescent [nonspecific ceiling light]) and with a spectrophotometer (Shadepilot). Reproducibility (precision) of color determination was characterized by the average of the highest percentages of interexaminer agreement for each specimen. Additionally, color differences (ΔE) were calculated based on CIELab values. ResultsThe mean reproducibility of the spectrophotometer was 92.2%, while for visual examination it was 43.7%. The corresponding differences in CIELab color space amounted to ΔEinstr=2.6 and ΔEvis=5.2. Illuminants and professional experience showed a significant influence, while sex did not. ConclusionWhile the spectrophotometer provided higher reproducibility, considering the color differences, the results obtained by visual inspection were still satisfactory. The differences due to type of illuminant, degree of experience, and sex of the examiners are of little practical relevance.

Effectiveness of Shade Measurements Using a Scanning and Computer Software System: a Pilot Study

Objectives: The aim of the present study was to evaluate a digital scanning and color measuring system in vivo in relation to the subjective, visual shade determination and an objective, wellknown digital spectrophotometric system. Methods: Shade determination with the 3D-Master system was performed at 29 patient including 87 teeth using a new scanning and computer-based system (3Shape TRIOS ® Color system), a well-known spectrophotometric computer-based system (MHT SpectroShade™) and the subjective visual shade assessment. The reliability of the two objectives and the subjective color assessment methods was calculated as an inter-individual comparison of the shade determination obtain by two dentists. Thereafter the validity of the objective methods was compared with the subjective methods by a pairwise comparison of color tabs selected by two dentists with each method. Each dentist determined which color tap was the best match. Results: The reliability of the objective, computer-based systems was high compared with the subjective, visual method for color determination. The validation test demonstrated no significant differences between the new Trios® Color System and the conventional, visual method and between the MHT SpectroShade™ spectrophotometric system and the conventional, visual method. Conclusion: The effectiveness of the new digital scanning and computer software system for color determination was as good as an earlier tested and validated digital colorimetric system and as the conventional, visual method for color determination of teeth.

Evaluation of an optimized shade guide made from porcelain powder mixtures

Color errors associated with current shade guides and problems with color selection and duplication are still challenging for restorative dentists. The purpose of this study was to evaluate an optimized shade guide for visual shade duplication. Color distributions (L*, a*, and b*) of the maxillary left central incisors of 236 participants, whose ages ranged from 20 to 60, were measured with a spectrophotometer. Based on this color map, an optimized shade guide was designed with 14 shade tabs evenly distributed within the given color range of the natural incisors. The shade tabs were fabricated with porcelain powder mixtures and conventional laboratory procedures. A comparison of shade duplication by using the optimized and Vitapan Classical shade guides was conducted. Thirty Chinese participants were involved, and the colors of the left maxillary incisors were selected by using 2 shade guides. Metal ceramic crowns were fabricated according to the results of the shade selection. The colors of the shade tabs, natural teeth, and the ceramic crowns were measured with a spectrophotometer. The color differences among the natural teeth, the shade tabs, and the corresponding metal ceramic crowns were calculated and analyzed (α=.017). Significant differences were found in both phases of shade determination and shade duplication (P<.017). The total number of color errors with the optimized shade guide was 3.5, which was significantly less than that of Vitapan, 5.1 (P<.001). The optimized shade guide system improved performance not only in the color selection phase but also in the color of the fabricated crowns.

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.

In vitro evaluation of color replication of metal ceramic specimens using visual and instrumental color determinations

It remains unclear whether or not the performance of intraoral colorimetric devices is accurate. The purpose of this study was to evaluate the color replication of metal ceramics using an intraoral colorimeter and visual shade determination. Twenty-five metal ceramic specimens were prepared to match 5 different shades (A1, B1, C3, D3, A3.5) of the Vitapan Classical shade guide. Five clinicians determined the shades of the specimens using the same shade guide. The shade determination was based on the agreement of at least 3 of the 5 observers. Instrumental shade determinations were made with an intraoral colorimeter (ShadeEye NCC) to obtain results in terms of the Vitapan Classical shade guide. Based on these shade determinations, 50 additional metal ceramic specimens (25 visually determined and 25 instrumentally determined) were prepared. The master (initial) and definitive (additional) specimens were analyzed with a spectrophotometer. L*, a*, b* values of each specimen were measured, and the color difference between the master and definitive specimens was calculated. The Wilcoxon signed rank test was used to analyze the color difference (ΔE) values (α=.05). Visual shade determination produced lower ΔE values than instrumental shade determination. The differences between ΔE values of different shade determination methods were significant for master specimens of the shades B1 and A3.5 (P=.02). The ΔE value calculated from the result of instrumental determination of shade B1 (ΔE=2.97) was within the clinically acceptable limit (ΔE=3.5), whereas the ΔE value for A3.5 (4.03) exceeded the limit for clinical acceptability. The ΔE values for C3 exceeded the acceptable limit for both shade determination methods (ΔE>3.5). Color replication of metal ceramic specimens using visual shade determination was more accurate compared to instrumental shade determination. The replication of the high-value shades (A₁-B₁) was observed to be reliable with both shade determination methods.

In vitro comparison of visual and computer-aided pre- and post-tooth shade determination using various home bleaching procedures

Due to inter- and intraexaminer differences, subjective evaluation of tooth color is deemed problematic. The purpose of this study was to evaluate the efficacy of home bleaching products, and to compare visual and computer-aided tooth shade determinations when various agents were applied. Human incisors (n=288) were stained (red wine, black tea) and allocated to 8 groups (n=36). Paint-on varnish (VivaStyle Paint On; 6% carbamide peroxide, CP) was used either for 1 x 20 min/d (VSP1), 2 x 20 min/d (VSP2), or 2 x 5 min/d (VSP25). Paint-on lacquer (Colgate Simply White, CSW; 5.9% hydrogen peroxide, HP) was applied for 2 x 30 min/d. Moreover, bleaching was performed using trays (VivaStyle, VS; 10% CP; 1 x 60 min/d, and Odol-med3 Beauty Kur, OBK; sodium chlorite; 2 x 10 min/d) or whitening strips (blend-a-med Whitestrips, BWS; 5.9% HP; 2 x 30 min/d). Water was used as control (1 x 60 min/d). Tooth shades were determined blindly (Chromascop Complete) after staining and 24 hours after final bleaching (visual and computer-aided assessment). Change in shade was analyzed using nonparametric methods (Kruskal-Wallis) and post hoc tests (Tukey and Kramer) (alpha=.05). Color changed significantly to lighter shades for all active agents. Analysis revealed significant differences among the control and all other groups, and among CSW/BWS versus VSP25/OBK, and VS versus OBK, for both evaluation methods. Additionally, significant differences were spectrophotometrically observed for VSP1/VSP2 versus BWS, and VSP2 versus OBK, with comparable reliabilities (0.995 at baseline; 0.994 after bleaching). Increased bleaching efficacy was observed with high peroxide concentrations; application time did not alter efficacy. Spectrophotometry was reproducible and objective. The 2 assessment methods matched 45.8% of the time.

Comparison of visual shade determination and an intra‐oral dental colourimeter

The choice of correct tooth shade for the fabrication of a restoration remains a challenge, even for experienced clinicians. The aim of this research was to evaluate and compare the precision of two different shade determination methods in terms of repeatability. Maxillary right central incisor of 10 patients was evaluated visually with the use of Vitapan Classical shade guide by five observers and instrumentally with the Vitapan classical shade guide values of ShadeEye NCC intra-oral colourimeter three times consecutively. The in vivo repeatability of methods were analysed with the spectrophotometric L*, a*, b* values of the shade guide (Vitapan Classical). Within the limitations of this study, the repeatability of instrumental (intra-oral dental colourimeter) and visual shade determinations were acceptable.

Comparison of in vivo visual and computer-aided tooth shade determination

The aim of this study was to evaluate the performance of shade-determining devices. For the daily practitioner, it is essential to know whether modern computer-aided shade selection is reliable in everyday life. So the question of how the clinical usability of these machines could be rated has to be clarified. In the following, three actual devices available in the market were compared using a human observer's perception. The SpectroShade device (MHT Optic Research AG, 8155 Niederhasli, Switzerland), the ShadeVision device (X-Rite Co., Grandville, USA) and the Digital Shade Guide DSG4 (A. Rieth, 73614 Schorndorf, Germany) were assessed with respect to their agreement with the color perception of three examiners looking at 57 test persons (six teeth each for a total of 342). Shades were reported in Vita Classical shades. It could be demonstrated that every single human examiner showed a significantly higher agreement value (human group on average 40.2%) when compared with the remaining five methods than each computer-aided tooth shade determination device. The devices reached on average only a value of 28.6%, whereas the X-Rite ShadeVision showed a significant better result (33.2%) than the MHT SpectroShade and Rieth DSG4 (27.0 and 25.7%). Identical shade results given by all three methods of a group (group of three devices and three humans) were found to be rather low for the computer-aided devices (9.9%) compared with humans (36.7%). All six methods together agreed in 3.3% of the cases. It becomes evident that the methods-especially the computer-aided shade determination-are rather divided about the respective tooth color. Deficiencies of the instrumental as well as the visual detection become obvious. The best agreement level was performed by the human examiners. The best agreement of the evaluated devices was obtained-generally as well as among the human testers-by the X-Rite ShadeVision system, followed at a statistically significant distance by the MHT SpectroShade and the Rieth DSG4. The agreement among the examiner group was 52.9%, significantly better than that of each device compared to this group (31.3% on average). Color detection and its realization are very complex. As shown, in many cases, computer-aided color shade determination of natural teeth seems to not reflect human perception.

DEVELOPMENT OF FIBER OPTICS SPECTROSCOPIC TOOTH COLORIMETER USING WHITE LED

Tooth colorimeter provides the determination of patient's tooth shade, and assists dentists, technicians and patients in satisfying the clinical needs for dental medicine. The traditional visual matching approaches of tooth shade tabs had some limitations that are based on subjective color perception and could be easily affected by environmental factors. In this research, we have developed a fiber optics spectroscopic tooth colorimeter with white LED, instead of the tungsten lamp to improve the size and heat problems. We have also developed a Whiteness-Yellowness index to simplify the tooth color information and have achieved an objectively and quantitatively tooth color representation.

Colour perception of laboratory-fired samples of body-coloured ceramic

The objective of this investigation is to test by common perception, the colour fidelity of laboratory-fired samples of ceramic. Thirty-two ceramic discs were constructed in a thickness similar to that used for ceramic veneers using eight shades from each of four different manufacturers. A group of 20 `adept' observers colour matched the samples in strictly controlled viewing conditions using a Vita Lumin® (Vita Zahnfabrik) shade guide. Samples were categorised as `positive matches' (matching the expected shade), `agreed shades' (matching an unexpected shade), or as `unidentified shades' (no match). The Vita Lumin® (Vita Zahnfabrik) colour `value' index was used as a reference to categorise colour `value' differences between observed and expected shade. Colour `value' selection was divided into three groups: (1) matching colour `value', (2) shades of higher colour `value' than expected or (3) shades of lower colour `value' than expected. Only six of the 32 samples examined were perceived to be `positive matches' with the recommended shade guide. Fourteen `agreed shades' were found while the remaining 12 shades were regarded as `unidentified shades'. The vast majority of observations disagreed with the manufacturers' designated shade. A significant trend was found favouring higher `value' (lighter) shades than those specified by the manufacturers. Significant differences in the pattern of shade matches and disagreements between brands were also found. Alternative shade determination systems and/or ceramic colour modifications are required if colour fidelity between the shade guide and the materials tested is to be improved.

Evaluation of visual and instrument shade matching

Statement of problem. Visual color matching to determine shades in dentistry is inconsistent and unreliable. If accurate, instrumental measurement of tooth color would provide objective, quantified data to match natural teeth to clinical shade guides. Purpose. This study evaluated and compared the ability of a new computerized colorimeter and a simple visual test to match ceramic shade guide teeth. Material and methods. Thirty-one (n = 31) observers with normal color vision were allowed unlimited time to match one set of Vita Lumin shade guide teeth to the corresponding shade guide teeth of a second Vita Lumin shade guide. The same test was administered to 14 of the observers several months later to determine within-subject variability. A computerized colorimeter (Colortron II) equipped with a positioning guide was used to measure the middle third of each shade guide tooth. Through a “match tool” present in the computer’s software, readings from one shade guide were matched with readings of the other shade guide by using CIELAB measurements and ΔE values. The mean number of correct matches by the colorimeter and of correct matches in visual test were compared with a 1-tailed t test. Repeatability for both tests was determined with a paired t test. Results. The Colortron II instrument correctly matched 8 of the 16 tabs (50% correct), whereas visual matching by examiners averaged 7.7 of 16 correct matches (48% correct) (standard deviation 2.7). No statistically significant differences existed between the 2 methods. The colorimeter demonstrated 100% repeatability and the visual test demonstrated fair repeatability (correlation coefficient r = .60). Conclusions. Shade determination by visual means was inconsistent. Accuracy of a new colorimeter in matching porcelain shade guide teeth was only slightly better. (J Prosthet Dent 1998;80:642-8.)

A comparison of smoke shade and gravimetric determination of suspended particulate matter in a semi-arid climate (Baghdad, Iraq)

Concentrations of suspended particulate matter (SPM) have been measured simultaneously in Baghdad, Iraq, using a high volume gravimetric procedure alongside a low volume sampler with smoke shade determination of OECD standard smoke. No correlation is seen between the gravimetric and smoke shade measurements, except when a single northwestern wind sector is taken. It is concluded that natural wind-blown dust constitutes the major source of SPM in Baghdad and that application of international air quality guidelines for SPM is problematic and probably inappropriate.

Improved color matching of metal-ceramic restorations. Part I: A systematic method for shade determination

The inherent problems in present shade matching procedures and communication between dentist and ceramist have been discussed. These five areas of weakness include (1) the observer, (2) variable viewing conditions, (3) commercially available shade guides, (4) inadequate technology, and (5) poor communication. A systematic procedure that breaks down shade selection to the elements of opaque, body, and incisal porcelain shades was presented. This method simplifies and adds clarity in the registration of shades, improving the communication chain between dentist and ceramist. The system is suggested as a means to overcome many of the inherent problems in shade selection and communication. This approach enhances the dentist-ceramist team's ability to esthetically match metal-ceramic restorations to the natural dentition. Future parts of this series will present procedures for improved communication and a system for porcelain application.

JAUNDICE IN MYOCARDIAL INSUFFICIENCY

The occurrence of outspoken jaundice with yellow sclerae and bile pigments in the urine as an incident in myocardial insufficiency was long ago observed, but is not common. Very frequent, on the contrary, is the development of a faint yellow or brownish-yellow pigmentation of the skin without the presence of bile pigments in the sclerae or urine. Determination of the exact shade of the coloration is made more difficult by the usual accompaniment of cyanosis, a condition that makes the jaundice more readily perceptible on the skin of the abdomen than on that of the extremities or face. This frequent combination of slight ochrodermia with the dusky tinge of cyanosis has resulted in the application of the term cyanotic icterus to the condition. Recent investigations have shown, in fact, that many patients with myocardial insufficiency have an increased amount of bilirubin in the blood. Bilirubin in the urine is rare,