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Color of Gingivaltissues of Blacks and Whites Color of Gingival Tissues of Blacks and Whites JOHN M. POWERS, JACQUELINE A. CAPP, and ANDREW KORAN School of Dentistry, University of Michigan, Ann Arbor, Michigan 48109, USA Value, chroma, and hue of attached gingiva measuring skin color that include visual com- of blacks and whites were measured clinically parison with comprehensive color charts and with Munsell color tabs. The color of non- wheels, spectral reflectance with use of a spec- mottled gingiva of blacks and whites was simi- trophotometer, and comparison with colored lar. The color of gingiva pigmented by melanin filters by colorimetry. Application of the latter in blacks was similar in hue, but lower in value two techniques for scientific measurement of and chroma than nonmiottled gingiva. skin color have not been used for measuring the Quantitative information on the color of color of the gingiva because of the inaccessi- healthy gingival tissues would be useful for the bility of the mouth to suitable instruments. The development of more natural-appearing den- Munsell color system and its potential use in ture resins for blacks and whites. dentistry have been reviewed in detail by Wright1 has reviewed three methods of Sproull.2-4 The purpose of this investigation was to This investigation was supported by General Re- search Support Grant RR 05321 from the National In- measure the color of uniformly pigmented, at- stitutes of Health, Bethesda, Md. tached gingiva of black and white patients and This article was presented, in part, at the 54th gen- eral session of the IADR, March 1976, Miami Beach, Fl. the color of gingiva pigmented by melanin in Received for publication March 5, 1976. black patients under clinical conditions by use Accepted for publication March 30, 1976. * ts4unsell Color, Baltimore, Md. of the Munsell color system.* I't UACK FIG 1. Munsell scales of hue, value, and chroma in color space (reprinted with permission of Munsell Color, Baltimore, Md). 112 701l. 56 No. 2 COLOR OF GINGIVAL TISSUES 113 Materials and Methods measured. Hue was measured on a scale from 2.5 to 10 in increments of 2.5 for each of the Each of three investigators was instructed hue was de- the ten color families. The red-purple in the Munsell color system (Fig. 1) with signated as RP, the red hue as R, and the use of color samplest and tested for color For example, an obser- aptitude with the yellow-red hue as YR. vision anomalies and color be recorded as 7.5R 5/4 to indi- use of a hue test.+ Finally, comparisons of ob- vation could were made with use cate hue of 7.5 R, a value of 5/, and a chroma servers and of light sources of/4. Each patient was examined under the of a color rule.§ the clinic and under The color of a selected area of the at- fluorescent light present in was simulated daylight from a portable source/ tached gingiva in dentulous patients of 6,000 K. matched with color tabs (glossy finish).# The with a correlated color temperature and a set of tabs If disagreement in color match existed between patient's lips were retracted color match was held adjacent to the area to be measured. the investigators, then a concensus Value was determined first by selection of a tab was agreed on by them and recorded with the that most nearly corresponded with the light- initial matches. ness or darkness of the gingiva. For example, Color difference (I) between colors meas- value was designated as 5/ on a scale from 0/ ured under fluorescent light and simulated (black) to 10/ (white). Then chroma was de- daylight was determined with the use of an termined by use of tabs that were close to the equation derived by Nickerson,5 I = C/5) value of the gingiva but were of increasing (2AH) + 6AV + 3AC, where C is the average chroma, A\H is the difference in hue, V is the saturation of color. For example, chroma was in designated as /4 on a scale from /0 (neutral difference in value, and zAC is the difference chroma between the two observations. zvH, AV, gray) to /14 (high saturation of color). The Mean hue of the gingiva then was matched with tabs and AC were always taken as positive. chroma already values of I were compared statistically with corresponding to the value and Scheffe intervals6 computed from the analysis of variance.7 t Student Set (11 charts), Munsell Color, Baltimore, Md. A total of 200 patients that included 100 $ Farnsworth-Munsell 100 Hue Test, Munsell Color, blacks and 100 whites were studied. The color Baltimore, Md. § Davidson and Hemmendinger Color Rule, Munsell of uniformly pigmented or nonmottled, at- Color, Baltimore, Md. tached gingiva between the central and lateral # Munsell Book of Color, Munsell Color, Balti- maxillary incisors was measured for each of more, Md. / Ney-Lite, J. M. Ney Co., Bloomfield, Ct. these patients. In addition, the color of mottled 10 9 IORP 2.5R 5.OR 7.5 R IOR 8 0 : 0 7- 0 @ 4 020 02 @4 6 @ 2 @40 0130202 @11 * 0 w *2 @8 0 @0 5 *3 012 *2 @4 0 -J 4 0 0 3 0 2 1 v -1- 4 2 4 6 2 4 6 2 4 6 2 4 CHROMA FIG 2. Value, chroma, and hue of nonmottled areas of attached gin- giva of 100 black patients measured under fluorescent light. Numbers ad- jacent to data points represent sample size of each point. 114 POWERS ET AL J Dent Res February 1977 10 9 2.5 R 5.0R 7.5 R IOR 8 * 3 0 0 7- 0 10 0 *10 @ 2 0 0 4 0 3 @ 6 6 0 0 10 @ 4 0 4 010 @3 @2 0 2 0 * 8 @ 3 @ 3 0 J @ @ 2 -a 5 2 0 4 3 2 C I IU 4 5 6 4 5 6 4 5 6 4 5 6 CHROMA FIG 3.-Value, chroma, and hue of attached gingiva of 100 white pa- tients measured under fluorescent light. Numbers adjacent to data points rep- resent sample size of each point. gingiva (pigmented by melanin) was meas- 7/ was observed for 95% of the white patients, ured for 61 of the black patients. The general but only 5% had a value of 5/ or lower. In 74% oral health and oral habits of each patient were of the observations, chroma was equal to /4. observed and recorded on an oral diagnosis Hue ranged from 2.5R to lOR, but 80% of the form. The form and density of the gingival tis- observations were from 5R to 7.MR. sues were observed and the position of epi- The value, chroma, and hue of mottled thelial attachment and sulcus depth were also gingiva pigmented by melanin of 61 black pa- recorded. Patients with pathosis of the gingival tients measured under fluorescent light are tissues were excluded from the study. shown in Figure 4. A value between 3/ and 4/ The informed consent of all human sub- was observed for 90% of the patients. In 87% jects who participated in the experimental in- of the observations, chroma was equal to /1 or vestigation reported or described in this article /2. Hue ranged from 2.5R to 2.5Y, but 70% of was obtained after the nature of the procedures the observations were from 5R to 7R. and possible discomforts and risks had been Under conditions of simulated daylight, ob- fully explained. servations of value greater than 7/ increased from 3 to 13% for nonmottled gingiva of black Results patients and from 5 to 27% for gingiva of white patients. For gingiva pigmented by melanin in The value, chroma, and hue of uniformly black patients, observations of value greater pigmented (nonmottled), attached gingival than 4/ increase from 10 to 16% when de- tissues of 100 black patients measured under termined under simulated daylight. There was fluorescent light are shown in Figure 2. A value no dramatic change in the distribution of ob- between 5/ and 7/ was observed for 94% of servations of either chroma or hue when de- black patients. Of the black patients, 25% had termined under simulated daylight for black or a value of 5/ or lower. In 84% of the observa- for white patients. The I's between measure- tions, chroma was equal to /4. Hue ranged ments made under fluorescent light and under from 1ORP to lOR, but 79% of the observa- simulated daylight for white patients, black tions were from 5R to 7.5R. patients with nonmottled gingiva, and black The value, chroma, and hue of uniformly patients with mottled gingiva were 3.6, 2.6, and pigmented, attached gingival tissues of 100 1.1, respectively. There was no statistical differ- white patients measured under fluorescent light ence between the first two values of I, but both are shown in Figure 3. A value between 5/ and were different from I = 0 at the 95% level of Vol. 56 No. 2 COLOR OF GINGIVAL TISSUES 115 confidence (Scheffe interval was 1.6). The fluorescent light. Measurements made under third value of I was different statistically from simulated daylight approximate the require- the first at the 95% level of confidence (Scheffe ments of condition 3 more closely. interval was 1.9) but not from the second value In 141 of 261 instances, a color change was of I or from I = 0. seen between fluorescent light and simulated A total of 522 color matches was made in daylight. Of these 141 instances, 75% were the this study.
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