IESI

When male and female patients, dental students, and dentists evaluated drawings and photographs of maxillary central incisors of varying

shape, symmetry, and proportion, it was found that the preferences of dentists and patients differed significantly.

Esthetics: a comparison of dentists' and patients' concepts Arthur S. Brisman, DDS

., : ~ :;1 ental esthetics is a science based on the general taste of society. Certain shapes and arrangements of teeth may be considered esthetically pleasing when many patients agree that they are. Investigators may take surveys to discover what forms, shapes, colors, and other sensory impressions are generally pre-ferred.

The dentist creates an illusion. He learns concepts of perception l and tries to achieve the patient's de-sires for an esthetic appearance. Unfortunately, den-tists may develop concepts of anesthetic appear-ance that differ from patients'. This can create com-munication problems and unanticipated difficul-ties.

Tooth shape and harmony In 1914, Williams concluded that human teeth could be classified into three principal shapes: rec-tangular, triangular, and ovoid.2 Williams claimed that the most pleasing appearance is one in which the outline form of the individual's face turned up-side down and the outline form of the individual's maxillary central incisor are identical. Williams's method of harmonizing the face with teeth has been popular for more than 60 years.3 This is remarkable because the outline forms of the face and the maxil-lary central incisor coincide in only a small percent-age of cases, and it has never been proved that this occurrence results in an ideal esthetic appearance.4

Perhaps the only major addition to Williams's concept of esthetics was the attempt by Frush and FisherS to harmonize the teeth with a patient's sex, personality, and age (SPA factor). According to this concept, women are considered to be round, soft, and delicate and, for proper harmony and esthetics,

should be given round, soft, and delicate teeth (tapering/ovoid). Men are thought of as square, an-gular, and rugged and should be given teeth that harmonize with this image.6 Developing this idea to its natural conclusion, we must assume that old pa-tients prefer old and defective teeth to match their age and physical condition, and unpleasant patients are to be given unpleasant teeth to match their per-sonality.

Attempts to create an individualized dental com-position for each patienp7 conflict with the hypoth-esis that there are standard concepts of beauty in so-ciety that develop from social, cultural, and psycho-logical considerations and that each person wants teeth that conform to these concepts.

Symmetry Any concept of esthetics must consider symmetry.s In another field, Furtwangler9 wrote: "Symmetry re-fers to the regularity or balance in the arrangement of forms and objects. There are two kinds of sym-metry, horizontal or running symmetry, and radiat-ing or bilateral symmetry." Horizontal symmetry occurs when the design shows similar elements from left to right in a regular sequence. This type of symmetry is psychologically predictable and com-fortable but tends to be monotonous. l The dentition approaches horizontal symmetry when all the teeth have the same shape; that is, when they look like central incisors. Radiating symmetry results when'. the design extends from a central point and the left and right sides are mirror images. Elongating the central incisors and narrowing the lateral incisors will exaggerate the effect of radiating symmetry.

According to the Academy of Denture Prosthe-'ADA. Vol.l00 . Man:h 1980 345

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tics,10 "anterior crowns should maintain some of the irregularities observed in natural teeth to be estheti-cally acceptable." But, according to psychologists,l1 "forms and designs which are repetitive and regular (symmetrical) are usually found to be more pleas-ing." Teeth are seldom symmetrical, although pa-tients think they are. There must be some irregu-larities if teeth are to appear natural; however, this does not mean they are esthetically pleasing to the patient. Patients may prefer teeth that look artificial or unnatural but are closer to their concept of the ideal esthetic appearance .

Proportion Proportion is another important concept of esthe-tics. We will consider the relationship between the length and width of.the tooth. The average maxillary central incisor has a length-to-width ratio of 10:9. Yet, the recommended proportion in dental anatomy and for dental laboratory technici~s is 10.5:8.5.12.13 This discrepancy can only be ex-plained by the empirically derived impression that elongating the central incisor will result in a more esthetically pleasing arrangement. It has also been suggested that the cervical mesial-to-distal dimen-sion be widened from 6.5 to 7 mm. This reduces the taper of the tooth; a squarer incisor is created.

When the central incisor is elongated, it ap-proaches an interesting length-to-width proportion, 3:5. Artists, architects. and psychologists have found that people prefer lines and areas that can be divided approximately in the ratio of 1 to 0.618, or approximately 3 to 5. The Greeks may have used this proportion in art and architecture. It was studied by Fibonacci, a 13th century Italian mathematician, and is currently used in designs by commercial art-ists. I 4-16 Dentists have also written about the golden proportion. t.17 Levin even developed a grid that re-lates central incisors, lateral incisors, canines, and premolars in a 3:5 proportion. IS

Study objectives The evaluations described in this paper have tried to answer, with respect to symmetry. proportion, and shape of teeth, these questions:

-Is there a shape of teeth (square, tapered, or ovoid) that is preferred?

-Is symmetry preferred? -Is radiating symmetry preferred to horizontal

symmetry? -Are elongated teeth with a length-to-width ratio

of 3:5 (the golden mean) preferred? -Are dentists and dental students' concepts of

esthetic appearance similar to those of patients? -Are square teeth considered masculine. are ta-

pered ovoid teeth considered feminine, and do 348 JADA, Vol. 100, March 1980

women pref~r a different and presumably Illore feminine type of teeth?

Methods Preferences of patients, dentists, and dental stu-dents with respect to shape, proportion, and sYm-metry of maxillary incisors were investigated by analyzing their choices in a series of studies. The pa-tients were white, middle-class men and WOIllen who lived in the greater New York area. Ages ranged from 20 to 70 years; none of the patients wore den-tures. The dental practitioners and students were men. The dentists had a minimum of three years' experience. The students were seniors at New York University College of Dentistry. Totals of 112 den-tists, 215 dental students, 695 female patients, and 399 male patients were used for the different studies. No participant answered more than three of the nine surveys.

Studies 1 and 2 evaluated the preferences of the four groups to variations in drawings of basic shapes and photographs of variously shaped maxillary teeth. Study 3 evaluated preferences to photographs of two set-ups of so-called masculine or feminine teeth. Studies 4, 5, and 6 evaluated preferences to drawings and photographs of teeth of the same shape but with different length-to-width propor-tions. Studies 7 and 8 evaluated preferences to draw- . ings and photographs of teeth of different symmetry but which had the same shape and proportion. Study 9 evaluated preferences to teeth of varying combinations of shapes and symmetry but with the same proportions.

Data and illustrations for the nine studies are found on the following five :oages. Discussion fol-lows Study 9.

Participants were asked to list their choices as: best, second best, third. and so forth. A weighted score for each reply was obtained by totaling the scores of the respondents in each group (dentists, dental students, and male and female patients). First choice was given a weight of 1, second choice was weighted as 2, third choice was weighted as 3, and so forth. The lower the total score, the more favor-able the response.

By ranking the weighted replies, we attempted to test the consistency of the replies among the four groups. The closer the weighted score was to 1, 2, or 3. the more consistent were the replies to the test within the group. Complete consistency rarely oc-curred within each group; often, the weighted scores for two of the choices were close.

Differences in weighted totals for the four groupS in each study were tested for statistical significance by the chi-square test. This tests whether the dif-ferences in weighted rank scores among groups of subjects were statistically significant or could have occurred by chance.

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Table 1 Mean scores and rankings of preferences of four groups of respondents (male and female patients, dental students and practitioners) for basic shapes of teeth as seen in Study 1 (Fig 1).

Group MalePatieots (0 = 80)

Ovoid Squar" Triangle

Female patients (n = 118) Ovoid Square Triangle

Students (n = 68) Ovoid Square Triangle

Dentists (n = 27) Ovoid Square Triangle Note: x' = 8.41; df = 6; P> ,OS,

First choice

41 37 2

68 50 a 53 13

2

23 4 a

Second Third Mean choice choice score

36 3 1.52 35 8 1.64 9 69 2,84

40 10 1.51 56 12 1,68 22 96 2.Bl

14 1 1,24 42 13 2,00 12 54 2,76

4 a 1.15 20 3 1,96

3 24 2.89

Fig 1 Basic square, ovoid, and triangular forms that were shown to participants. All dentists chose ovoid fonn as first preference.

Rank

1 2 3

1 2 3 1 2 3 1 2 3

A

. Study 1: Basic shapes, drawings. Three shapes-square, ovoid, and triangular-were shown to partici-pants who were asked to give their preferences (Fig 1). They were not told the shapes represented teeth al-though this was inferred by most par-ticipants because of the test situation. Table 1 shows the preferences of each of the four groups, the mean scores, and the ranks of the mean scores. All groups chose the ovoid as their first choice, the square as second choice, and the triangle as third choice.

B c

Table 2 Mean scores and rankings of preferences of four groups for basic shapes of teeth as seen in photographs of maxillary central incisors in Study 2 (Fig 2).

Shape of tooth

A. Square ovoid

B. Ovoid C. Tapered

ovoid Note: x' = 7.15; df - 8; P> .05.

A

Male patients (n = 80)

Mean score Rank 1.80 Second 1.65 First 2.55 Third

Female patients (n = 118)

Mean Mean score Rank scor~ 1.63 First 1.93 1.66 Second 1.43 2.71 Third 2.64

B

Fig 2 Photographs of maxillary central in-cisors that were closely associated in form with drawings shown in Figure 1. A, square ovoid; B, ovoid; and C, tapered ovoid. Ovoid was first choice, especially of dentists.

Students Dentists (n = 68) (n = 27)

Mean Rank score Rank

Second 2.11 Second First 1.37 First Third 2.52 Third

Study 2: Basic shapes, photographs. This study was designed to deter-mine if the participants' preferences ' in Study 1 carried over to photo-graphs of maxillary central incisors. For this study, the triangular shape was softened to make a tapered ovoid, and the square was made a square ovoid (Fig 2). Table 2 shows that the choices followed a pattern similar to that in Study 1. Ovoid was first choice in three of the four groups and virtually tied for first choice of female patients. Differences in . weighted "ore' were not 't.ti,tJ cally significant. ;

Brisman: ESTIlETICS 347

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Table 3 Percentages of respondents preferring masculine (Fig 3, A) or feminine (Fig 3, B) teeth as seen in photographs in Study 3.

Which do you prefer?' Masculine teeth (A) Feminine teeth (B) Which would you prefer for

yourself?t Masculine teeth (A) Feminine teeth ~) Which do you t ink is more

masculine?:!: Masculine teeth (A) Feminine teeth (B) No opinion

x' = 1.41; df = 3; P> .05 . tx' = 1.18; df = 3; P > .05. tx' - 3.66; df = 3; P > .05.

Male patients (n = 60)

%

60 40

58 42

78 12 10

Female Male patients students

(n = 100) (n = 40) % %

69 68 31 32

65 68 35 32

74 80 10 20 16

lOne dentist thought set-up B was more masculine because it looked uneven and irreglliar.

A B

Male dentists (n = 25)

%.

64 36

60 40

96 4

Fig 3 Photographs used to evaluate concept that square ovoid central incisors (A) are masculine and tapered ovoid central incisors (B) are feminine. Female patients preferred square ovoid shape (A).

Male patients Female patients Length- (n = 70) (n - 1(0) to-width Mean Mean Mean proportion score Rank score Rank score A. 3;2 1.69 Second 1.98 Second 1.84 B. 5:4 2.87 Third 2.74 Third 2.82 C.9:10 4.29 Fourth 3.99 Fourth 4.67 D.2:1 4.61 Fifth 4.64 Fifth 4:32 E. 4:3 1.54 First 1.65 First 1.35

Note: X' - 13.01; df = 12: P > .05.

A B

Study 3: Masculine and feminine teeth. In Study 3, we investigated the concept that square central inCisors are masculine and tapered ovoid cen-tral incisors are feminine (Fig 3). AU groups preferred masculine teeth (the square ovoid shape) to the feminine teeth (the tapered OVoid shape), and the differences were not statistically significant. When asked "Which would you prefer for Your-self?", a similar percentage of Partic-ipants (including female patients) preferred the masculine teeth. Again, differences in responses were not statistically significant. In reply to "Which do you think is more mas-culine 1", 24 of the 2 5 dentists termed the square ovoid masculine. Al-though most of the patients consid-ered the square ovoid more mas-culine, many did not, and some could not decide. Differences in per-centages were not statistically signif-icant (Table 3).

Students Dentists (n = 55) (n = 25)

Mean Rank score Rank

Second 1.92 Second Third 2.80 Third Fifth 4.88 Fifth Fourth 4:04 Fourth First 1.36 First

c D E

Study 4: Proportions, drawings. This study evaluated the length-to-width proportion of teeth. The drawings of the five shapes in this study are square ovoids (Fig 4). They have the same widths but different lengths. In shape E, the length to width was 4:3; this was first choice of all groups. In shape A, the length to width was 3:2; this was second choice, and shape B, in which the length to width was 5:4, was third choice. Patients selected shape C, in which the length to width was 9:10, as fourth choice to the most elongated shape, shape D. Dentists and students, however, preferred

Fig 4 Drawings used to evaluate length.to-width proportion of teeth. Drawings A to E are square ovoids with same widths but different lengths. Shape E, with iength-to-width ratio of 4:3, was first choice of all groups, but dentists preferred teeth that were more elongated.

348 JADA, Vol. 100, March 1980

shape D, in which the length to width was 2:1, to shapeC (Table 4). Dentists were more consistent in their prefer-

ences than other groups. Differences in choices among the four groupS were not statistically significant. -

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Male patients Female patients Length- (n = 75) (n = 125) to-width Mean Mean proportion score Rank score Rank A. 9:10 3.80 Fourth 3.66 Fourth B.5:4 1.63 First 1.58 First C. 10:9 2.07 Second 2.16 Second D.4:3 2.50 Third 2.60 Third

"Unanimous preference. Nole: X' = 3.852; df = 9: P > .05.

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Students (n = 50)

Mean score Rank 3.88 Fourth 1.54 First 2.26 Second 2.32 Third

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Mean score 4.00 1.58 2.21 2.21

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Dentists (n = 29)

Rank Fourth" First Second (tied) Second (tied)

Fig 5 Drawings of pairs of central incisors used to evaluate preferences in length-ta-width propor-tions. Drawing B-with length-ta-width proportion of5:4 (proportion presented in manuals for dental laboratory technicians)-was most favored. Drawing A was unanimously rejected by dentists al-though highly favored by patients.

Study 5: Proportions in pairs, draw-ings. Study 5 compares four draw-ings of pairs of central incisors (Fig 5). Drawing A represents central in-cisors with a length-to-width ratio of 9:10. This is the average proportion of deciduous central incisors19 and corresponds with shape C in Study 4. Drawing B, in which the length to width, 5:4, corresponds to shape B in

Study 4, represents the ideal propor-tion presented in manuals for dental laboratory technicians and is suggested for waxing-up of teeth in dental anatomy.13.20 Drawing C, in which the length to width is 10:9, is the average dimension of the central incisor.19 Drawing D, in which the length to width is 4:3, corresponds to shape E, the preferred proportion in

Study 4 (Fig 4). Table 5 shows that drawing B was

the most favored of all four groups, although this proportion (5:4) ranked third in the drawings of individual teeth in Study 4. Drawing D ranked as third choice of patients and students but tied for second choice for den-tists. Differences between groups were not statistically significant.

Table 6 Mean scores and rankings of preferences of four groups for various proportions of maxillary teeth as seen in photographs of set-ups (Fig 6) in Study 6.

Length-to-width proportions A. 10:9 B. 5:4 C. 3:2

Male patients (n = 70)

Mean score 2.64 1.46 1.90

Rank Third First Second

"Preference was tied for second choice. Note: X' - 20,005; dt - 6; and P < .02.

c

Female patients (n = 110)

Mean Mean score Rank score 2.47 Third 2.68 1.39 First 1.59 2.14 Second 1.53

B

Fig 6 Photographs of three set-up. used to evaluate preferlBlcas in length-ta-width propor-tions of clBltral incisors. Patients favored B (5:4 ratio) first and C (3:2 ratio) second; dentists and dental students favored C, then B.

Students Dentists (n - 85) (n = 54)

Mean Rank score Rank

Third 2.97 Third Second" 1.64 Second First" 1.39 First

Study 6: Proportions of set-ups, pho-tographs. In the photographs of three set-ups in Study 6, shape and sym-metry are constant, and only length-to-width proportion of the central in-cisors is changed (Fig 6). Photograph A has a length-to-width ratio of 10:9; B has a proportion of 5:4 which was favored in Study 5; and C is elon-gated to a proportion of 3:2, the ratio favored second in Study 4. Table 6 shows that patients first chose Band then chose C, whereas dentists and students first chose C and then chose B. Photograph A was third choice in all groups. Differences in choice!> among groups were statistically sig-nificant.

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A B C Fig 7 Drawings ofteeth used to evaluate preferences ofvarious forms of symmetry: A. horizontal symmetry; B. asymmetry; and C. radiating symmetry. Dentists and dental students preferred radiating symmetry and rejected horizontal symmetry. Patients found horizontal symmetry pleasing.

Study 7: Symmetry, drawings. This study elicited preferences to draw-ings of teeth of different symmetry. Figure 7 shows drawings of horizon-tal symmetry (the effect was exagger-ated by drawing the lateral incisors and canines approximately the same size and shape as the central in-cisors), asymmetry, and radiating symmetry.

Table 7 shows a different pattern of I: choices for patients, students, and , dentists. Dentists were most consis- tent in their preferences. They pre-~.. ferred radiating symmetry, showed : interest in asymmetry. and disliked ; the drawing of horizontal symmetry. ! Students ranked radiating symmetry

Table 7 Mean scores and rankings of preferences of four groups for varying symmetry of maxillary teeth as seen in drawings (Fig 7) in Study 7.

Male patients Female patients Students Dentists (n = 40) (n = 80) (n = 130) (n = 80)

Mean Variants score Rank

A. Horizontal 1.56 Second symmetry

Third B. Asymmetry 2.98 C. Radiating 1.46 First

symmetry Preference was tied. tPreference was virtually tied. Note: X' = 67.24; df = 6; P < .001.

Mean score 1.57 2.86 1.57

first and ranked horizontal symmetry and asymmetry virtually the same.

Male and female patients almost unanimously rejected asymmetry

Mean Mean Rank score Rank score Rank First* 2.41 Secondt 2.90 Third Third 2.44 Thirdt 1.83 Second First' 1.15 First 1.27 First

(third choice), and equally preferred the radiating and horizontal symmet-ries. Differences in group preferences were statistically significant.

r Th8ble 8 hMeafnfscores and rafnkings. of prefher(eF~ces) ~f fsourdgroups for various degrees of radiating and horizontal symmetry as seim in I ,olog",' 0 ou"oIu" 0 .. 1"'0' I~I .g 8 on lu y 8.

Male patients Female patients Students Dentists

Mean Symmetry score

Radiating symmetry, degree 1 (B) 1.70 Radiating symmetry, degree 2 (C) 2.18 Horizontal symmetry (A) 2.74 Radiating symmetry, degree 3 (0) 3.38

Note: X' = 146.742; df - 9; P < .001.

Study 8: Symmetry, photographs. In Study 8, photographs of four set-ups of anterior teeth in which the arch of radiating symmetry was varied were shown to participants (Fig 8). Set-up A shows horizontal symmetry. the central incisors are even, and the lat-eral incisors approximate the size and shape of the central incisors. Set-up B shows radiating symmetry, degree 1 (1 to 2 mm); set-up C shows radiating symmetry, degree 2 (2 to 4 mm); and set-up D shows radiating symmetry, degree 3 (more than 4 mm). Set-ups B, C, and D have identi-cal lateral incisors and canines. The central incisors are square ovoids that are identical except for their po-sitions; the length-to-width ratios are the same.

Table 8 shows the mean scores and ranks. Both groups of patients pre-ferred teeth arranged in radiating symmetry, degree 1 (B). followed by degree 2 (C). They preferred horizon-1 tal symmetry (A) to radiating sym-

:1 metry, degree 3 (D). Dentists, how-

(n = 126) (n = 169) (n = 94) (n = 44) Mean Mean Mean

Rank score Rank score Rank score Rank First 1.56 First 2.28 Second 2.75 Third Second 2.18 Second 1.37 First 1.59 First Third 2.93 Third 3.90 Fourth 3.98 Fourth Fourth 3.33 Fourth 2.45 Third 1.68 Second

A

C D Fig 8 Photographs of four set-ups in which arch of radiating symmetry is varied. A, horizontal symmetry; B, radiating symmetry, degree 1 (1,t03 mm); C, radiating symmetry, degree 3, (3 to4 mm); and D, radiating symmetry, degree 3, (m.ore than 4 mm). Patients preferred B, foll_ed by C; dentists preferred C, followed by D, then B.

ever, rated degree 2 (C) as first choice, degree 3 (D) as second choice. and degree 1 (B) as third choice. Horizon-tal symmetry (A) was last choice; it was almost a unanimous last place

choice with a mean score of 3.98. Dental students' choices tended to resemble those of dentists. Dif-ferences in the preferences among groups were statistically significant. lL-, ____________________ ~ ____________________ ___

r" ;able 9 Mean scores and rankings of preferences of four groups. for teeth with .varyi~g shape and symmetry as seen in photographs of anterior maxillary teeth (Fig 9) III Study 9. . Study 9: Shape and symmetry, pho-tographs. Study 9 used photographs of five set-ups of teeth of varying shape and symmetry (Fig 9). Set-up A has square ovoid teeth arranged with horizontal symmetry; set-up B has tapered ovoid teeth with radiating symmetry. degree 3; set-up C has, square ovoid teeth with radiating .1 symmetry. degree 3; set-up D hasj square ovoid teeth with horizontal :1 symmetry; and set-up E has square .i ovoid teeth with an asymmetrical ar-J rangement. Set-ups C and E are 1

Variations of shape and

symmetry Set-up A Set-up B Set-up C Set-up 0 Set-up E

Mean score 2.15 4.88 2.15 1.90 3.92

"Preferences were tied.

Rank Second' Fifth Second' First Fourth

Note: X' = 484.29: df = 12: P < .001.

A

c

E

Discussion

Mean score 1.88 4.92 2.54 1.67 3.99

Mean Mean Rank score Rank score Rank

Second 3.65 Fourth 4.71 Fifth Fifth 3.84 Fifth 2.97 Third Third 1.96 First 1.55 First First 2.43 Second 3.28 Fourth Fourth 3.12 Third 2.49 Second

D

D

Fig 9 Photographs of five set-ups in which both shape and symmetry are varied: A, square ovoid teeth, horizontal symmetry; D, tapered ovoid teeth, radiating symmetry (degree 3); C, square ovoid teeth, radiating symmetry; D, square ovoid teeth with horizontal symmetry; E, square ovoid teeth, asymmetriw arrangement. Patients preferred set-ups A and D; dentists pre-ferred C but also liked asymmetrical arrange-ment shown in E.

1 nearly identical; the slight asymmet-, rical change in E is the only variant. ~l

Study 9 may be considered a com- ' posite of Study 7-in which drawing ,11' A resembles set-up D, drawing B re-sembles set-up E, and drawing C re- j sembles set-up C-and Study 3-in 1 which photograph A corresponds to ~ set-up A, and photograph B corre- ), .... j sponds to set-up B. :1

Table 9 discloses results of Study 9 ".',1.' that are consistent with the results of Studies 3 and 7. All the patients pre-ferred the horizontal symmetry in 1

I, set-ups A and D and disliked the ta- ,. pered ovoid feminine teeth in set-up B. The asymmetrical natural-looking ;1 teeth (set-up EJ, although only ', .. 1 slightly different from set-up C, were 1 consistently rejected. Dentists. how- 'j ever, although preferring C, liked the asymmetrical arrangment. Positive interest was shown in the tapered ovoid teeth, although that shape was picked third. Dentists gave the low-est preference to the horizontal symmetry of A and D; set-up A was almost unanimously picked as last choice. Mean scores for the students were closer than in the other groups; this indicated a lack of unanimous opinion. Differences in preferences were highly statistically significant.

Our studies dealt with only a few of the factors that can affect esthetic appearance. Other variables in-clude shade, size, arch form, and shape of the lips. The arrangement of teeth is important and different effects can be created from only one mold of teeth 21.22; yet our surveys show that dentists' and pa-tients' concepts of esthetic appearance may differ. Although dentists and patients have the same pref-erences for the shape of maxillary anterior teeth, the

preferences differed for proportions of length and width; there is a particularly large difference in the preferences with respect to symmetry of maxillary anterior teeth. Dental students seem to have prefer-ences that are between those of patients and den-tists. Both groups of patients had similar patterns of preferences.

The studies indicate that, when patients and den-tists observe individual teeth, they prefer an elon-gated tooth that approximates the ideal, 3:5, propor-tion (Study 4). However, when pairs of central in-

Drisman : ESTHI!TICS a 351

I !

"

cisors are evaluated, a less elongated tooth is pre-ferred (Studies 5, 6).

Most dentists dislike the piano key or picket fence composition; however, patients may prefer this look. In making dentures, it is easy to break up a mold, rotate teeth, and create a more natural look. When dentists believe it is necessary to soften the symmetry of this composition, they do so with timidity. Perhaps the canines are made slightly darker, and the incisors are slightly rotated. Sym-metry, p-owever, is not really destroyed, and the re-sults are virtually the same. Seldom will a lateral in-cisor differ significantly from the other, and never will the central incisors. This is not surprising, and dentists should not be criticized. Patients must be given dental compositions that conform with their concept of esthetic appearance and not necessarily with the dentist's concepts.

The dentist is challenged to take varied physio-logical conditions and limitations, and, with in-adequate materials and techniques, arrive at a rela-tively standard result for each patient.

Summary Drawings and photographs of shape, symmetry, and proportion of maxillary central incisors were evalu-ated by 112 dentists, 215 dental students, 399 male patients, and 695 female patients. A significant dif-ference was found between the evaluations of pa-tients and dentists; the preferences of dental stu-dents were between those of patients and dentists. Male and female patients had similar opinions.

The author thanks Dr. Larry Garfinkle. associate professor, department of removable prosthodontics, New York University College of Dentistry, for statistical evaluation and organization of the paper, Dr. Elias Karnoff, assistant professor, department of dental materials, New York University College of Dentistry, for the photographs; and Dr. Timothy Wong, instruc-tor, department of operative dentistry, for the artwork.

352 JADA, Vol. 100, Marcla 1980

Dr. Brisman is an associa~e cl~nical professor, ~epartment of fbted prnsthodontics, New York Uruverslty College of Dentistry, New York. Ad-dress requests for reprints to the author. 31 Washington Sq, New York, 10011.

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