An Analysis of SelectedNormative Tooth

Proportions

Robert ;. Gillen, DMD'Langley AFB, Virginia

Richards. Schwartz, DOS"University of Texas Health Science CenterSan Antonio, Texas

Thomas I. Hilton, DMD'"

Douglas B. Evans, ODS, MS"'

Wilford Hall Medical CenterLackland AFB, Texas

This Study was conducted io determine the average dimensions of the sixmaxillary anterior teeth in a targeted population and to evaluate therelationships belween intertooth and intratooth dimensions. Casts wereobtained from 54 patients ranging in age from 18 to 35. Measurements oflength and width were made on ihe casts using a digital caiiper. Using thesemeasurements, ralios were calculated: length to width, width to width, andlength to length. Although the tooth dimensions varied somewhat by raceand gender, the ratios were quite consisten!. In addition, the goldenproportion was not found to correlate with any of the calculated ralios.IrMj Prosthodont 1994;7:4W-417.

I n today's health- and esthetic-conscious world,the smile is considered an important component

of an individual's overall appearance and well-being. In fact, esthetics is often what motivatespatients to seek dental care.' Goldstein- reportedthat of 60 female beauty contestants, 97% per-ceived that they needed some esthetic improve-ment in their denti t ion. Mathews' stated thatpatients take function for granted and that as clini-cians we need to restore, enhance, or createesthetics to better serve their needs. Althoughincreased emphasis has been placed on dentalesthetics, there is little scientific data in the dentalliterature to use as a guide.

The early work in this area was dominated bytheories applicable to denture fabrication. The

•Major, U5AF, DC."Associate Professor, Department of General Practice, School

of Dentistry.'"Lt Col, USAF, DC.

Reprint requests: Dr Richard S. Schwartz, Department ofGeneral Practice, University of Texas Health Science Center,7703 Eloyd Curl Drive, San Antonio, Texas 78284-7914.

The views expressed in this article are those of the authors anddo not reflect the official policy of the United States Air ForceDental Services, the Department of Defense, or other depart-ments of the US Government.

"temperamental theory," which had been used inmedicine as a diagnostic tool since the 5th cen-tury, was related to tooth forms in the late 1800s.This theory applied the categories of sanguine,bilious, and choleric to tooth forms based on thedentist's impression of a patient's health andappearance.' As time passed, the temperamentaltheory was modified and incorporated into a clas-sification system based on facial fo rm/ ' This newertheory characterized facial form as either square,tapering, or ovoid, and matched it to tooth form.Guides to aid in denture tooth selection using thisrelationship between facial form and tooth formare still manufactured. However, a study by Cozza'showed that no correlation existed between thetaper of the head and that of teeth.

The next major movement presented In the liter-ature was the "dentogenic theory." In a series ofarticles by Frush and Fisher^-'" in the mid to late1950s, this term came to mean the art, practiceand techniques used to achieve esthetic goals indentistry. =-"> The proponents of this philosophy feltthat the "SPA Factor" (sex, personality, and age)dictated the fabrication of a patient's dentureAccording to this theory, dentures for womenshould incorporate a soft, spherical appearancewhereas dentures for men should be harsh and'angular. Subtle rotations and selective grindingwere used to characterize the patient's personality

The International lournal of Pros*odontic 410 ; 7 , Numbers, TÍ9

Selected Normative Toolh Proportions

Abrasion, migration, and spacing were used toreflect the age dii^erences. This theory is still popu-lar today.

The majority of scientific research in gender-based morphologic differences in teeth comes fromanthropology. Teeth are the most durable ofhuman remains," and thus it is logical that genderdetermination from teeth would be of vital impor-tance in anthropologie studies."" Accurate dentaimorphologic measurements and muitivariate statis-tical analysis were used to produce formulae thatwere 80% to 90% accurate in predicting the gen-der of the remains of several isolated populations(ie, Arikara Indian skeletons and individuals from aMeianesian population). However, the results werevalid only for specific isolated populations, and theformulae were not interchangeable between popu-lations. In addition, some populations show norelationship between dental morphology and gen-der. The measurements that were most predictiveof gender determination in these studies were thebuccolingual dimensions of the posterior teeth;however, these are not useful to a dental clinicianattempting to restore the anterior dentition.

The appearance of the dentition can be called itscomposition. Similar to a painting, the compositionis the sum and blend of all of its intricate parts.Most authors in the dental literature agree on theimportance of composition to dental esthetics.Many have attempted to look for consistencies inthe normal dentition to aid in restoration of com-promised situations. One example of a composi-tional norm that has been examined is the applica-tion of the "golden proportion" to dentistry. Thegolden proportion was first used in ancient Greekarchitecture. Its most basic premise is that whentwo objects are related to each other and theappearance is both natural and harmonious, thelarger to the smaiier forms a ratio of 1.618:1.Levin" discussed three dental relationships that5eemed to compare in this manner. When viewedfrom the facial aspect, the width of the centralincisor is in golden proportion to the lateralincisor, as is the lateral to canine and the canine toi irst premolar. He also stated that the incisal edgesof the maxillary incisors divide the lower third oftbe face into the golden proportion when themandible is at rest, and that the anterior segment isin golden proportion to the width of the smile.Shoemaker''-'' wrote a series of articles promotingthe golden proportion as an adjunct to dentistry.Lombardi'^ examined the golden proportion andconsidered another area of composition: how themaxillary teeth fill the "dynamic negative space."In the edentulous patient, the dynamic negative

space is the darkened area between the lips duringa wide smile. In the dentate patient, the maxillaryanterior teeth are framed within this space,Lombardi stressed the importance of composingthe teeth within this space to achieve maximumesthetics.

Several other authors investigated "esthetic"relationships. Tjan et a l " used the scientificmethod to establish whal was felt to be a composi-tional norm. The study used 454 full-face pho-tographs from a random population and reportedseveral findings. The overall cervicoincisal lengthof the maxillary anterior teeth is displayed when aperson smiles, and only interproximal gingiva isvisible. Maxillary anterior incisal edges parallel theinner curve of the lower lip when a person smiles,and the edges may be either totally touching or justtouching the lower lip. The six maxillary anteriorteeth, as well as the first and second premolars,also are displayed. Finally, the study reported thatthe midline corresponds to the harmonious bal-ance of the smile, and that gender could not bedetermined from the appearance of the anteriorteeth. Vig and Brundo'" addressed the amount oftooth visible at repose as it related to age and gen-der. In general, they found that men show more ofthe mandibular teeth than women and that womenshow more of the maxillary teeth than men, eventhough, overall, both show more of their maxillaryteeth than mandibular. With age, however, bothsexes increase the visibility of the mandibularteeth. Miller-' further supported the works of Vigand Brundo and Tjan et al. He felt that the maxil-lary anterior incisal edges generally paralleled thecurve of the lower lip and that this relationship waslost with age. Miller also felt that the teeth wereframed by the lips differently in maies and females.

Actual tooth size and morphology is addressedin dental literature but presents conflicting infor-mation. Wheeler-^ and Kraus et al-' reported aver-age tooth dimensions from an unknown number ofskulls of unrecorded gender, age, and race. Linek'sreported tooth dimensions" differ considerablyfrom those of Wheeler and Kraus et al. For exam-ple, there is a 2,5-mm difference in the length ofthe maxillary central incisor. Tooth dimensions arealso reported in several other studies.-""'' The con-cept that the length and width of a central incisoris related to skull length (1/20) and bizygomaticwidth (1/16), respectively, is commonly used toselect denture teeth.-"" This premise, however, isnot based on research. Kern" found no correlationbetween these structures and tooth size.

Today clinicians regularly restore maxillary ante-rior teeth, yet there are few guidelines available to

\ ï:-tume 7, Number S, 1994 411 The Inrernational Ioumai of Pro^thodontic

Fig 1 Max-Cal digital caliper altered with two straight pins loenhance its interproximal measunng capabilities.

Fig 2 Technique tor measuring the casts.

Fig 3 Diagrams of measurement lahels. Measurement L otcentral and lateral incisors is the most apical portion of theclinioal crown to the closest point in the middle third of theincisai edge. Measuremenl L ot canines is the most apicalportion ot the clinical crown to the cusp tip. Measurement W isthe greatest width of the tooth.

aid in selecting the proper size and shape of theseteeth and in determining their relationships. There-fore, the purpose of tbis study was to derive dimen-sional data on the clinical crowns of maxillaryanterior teeth in a study population and to deter-mine whether consistent dimensional proportionsexist between them.

Materials and Methods

Volunteer subjects were solicited and screenedby one individual from within the staff of theWilford Hall Medical Center Dental Directorate,The inclusion criteria were as follows:

1, No missing anterior teeth2, No gingival or periodontal conditions or iher-

apy that would alter a healthy tissue-to-toothrelalionship

3, No anterior restorations involving facial, inter-proximal, or incisai surfaces

4, No abraded, eroded, fractured, or altered ante-rior feeth (no exposed dentin)

5, No history of orthodontic treatment or toothsize alteration

6, Aged between 18 and 35 years7, Parents and grandparents known to be of black

or white race

Using these criteria, 54 individuals were selectedas samples for evaluation. Twenty-one white males,13 black males, 10 white females, and 10 blackfemales were sampled. Anterior maxillary quadrantirreversible hydrocoiioid IJeltrate Plus, LD Caulk,Mi i ford, DE) impressions were obtained. Theimpression powder (28 g) was combined withdistilled water (68 cc) and mixed for 12 secondsusing a mechanical mixing device under vacuum(Vacu-Vestor, Whip Mix, Louisville, KY), Priorto pouring, the impressions were sprayedwith Alcide LD (Alcide Corp, Norwalk, CT), a chlo-rine dioxide-based disinfectant, and placed in aplastic bag for 3 minutes. They were then rinsedwith tap water and poured in Die Keen, a type Vdental stone (Columbus Dental, Sf Louis, MO) with-in 12 minutes. The casts were numbered from1 to 54,

. . „ ^ _ , . '"^ '^¡gital caiiper (Fowler &NSKSt Louts, MO), accurate to 0,01 mm, wasmodified and used for all measurements (Fig 1)The modification involved attaching two straightpins to each side of the caliper to allow moreaccurate placement on the casts (Fig 2), The pinsextended 3 mm from the tips of the caliper andopened the caliper 1 mm. The caliper was zeroedat this opening.

a I Q( Prosthodorlics 412 nc 7, Number 5, " •

Sf 1er led Normjiive Tontli Proporliors

Table 1 Mean Values (in mm) of All Measurements of the Maxillary Anterior Teeth"

L rigtil canine L right lateral L right central L left canine

SampleMaleFemaleWhite maleBlack maleWhite femaleBlack female

SampleMaleFemaleWhite maleBlack maleVi/hite le m aleBlack female

Mean

t0.t35010.67009.2260

10.478610.98009,48208,9710

SD

1,40001,37500.91021.1 BIO1.64501,20000,4040

W fight canine

Mean

8,36678.56358.03208.33678,93008,03508.0290

SD

0,58710,55320.49260.45020.51770,58060.4187

Mean

8.69469.02908,12558,70299.55698.28307,9680

SD

1.19401,25900,82881.00491.48000.80340,8657

W right lateral

Mean

7,31807,50217,00507.36627.72156.79507,2150

SD

0,70830,72390.57080.72500.69340 43260.6341

Mean

10.174410,5529

9.531010,681410 34549.90609.1560

SD

1,07171,02850,82131 02971.03280.64590.B332

W right central

Mean

9,26289.34449,12409,14959.65929.05709.1910

SD

0.62030,63610,58170,51240,70800.51980.6589

Mean

10,383710.84419.6010

10.818010.88629,82909,3730

SD

1.04090,87240 82220,75711,06530.88500.7226

W left central

Mean

9.31729.39749.18109,24339,64629,17809.1840

SD

0 59830 63230.52270.52160.73320.46380.6014

Mean

8 76919.10188.20358.99769.27008.57907.8280

SD

1.20101.27950.80341.00721,66190,84750,5752

W left lateral

Mean

7 40527.53627.18257.31147.89926.90407.4610

SD0.78160,B6970.55450.61301.10570.50750,4683

Mean

10.178110.7506

9.205010.692910.84389.35809.0520

SD

1.34671.26000.84761.08691.54331.14390.3951

W left canine

Mean

8.36748,54978.05758 41628 76547 99708.1180

SD

0.50320.48120.37870.43850.48450.43310.3273

•L = The most apical portion al Ihe clinical crown lo tlie nearest point in the middle Itiirfl of ttie mcisal edge, or cusp tip en the canineW=Thegrealeslmesiai to distal width ot the tooth as measj/ed with the calipei ups placed interproximaiiy as tar as they will go.

The direct measurements recorded from gypsumcasts were as follows (Fig 3):

L — the most apical portion of the clinical crownto the closest point in the middle third of thetooth, on the incisai edge of the central andlateral incisors, and to the cusp tip of thecanine

W — the greatest width of the tooth as measuredwith caliper tips placed as far interproximallyas possible

Three consecutive measurements were made onthe first 10 casts to improve technique anddetermine reproduclbility. The measurements wereall within 0-2 mm of each other- The teeth onthe remaining casts were each measured once.All measurements were performed by the sameinvestigator.

The calculated values were as follows:

L;W — the ratio of length to width for each toothL:L— the ratio comparing the lengths of differ-

ent teethW:W — the ratio comparing the widths of different

teeth

The values and ratios were placed into cate-gories based on race and gender. A mean was cal-culated for each, and these were compared using atwo-way analysis of variance (ANOVA) withoutreplication.

Results

Table 1 lists the mean values for each of thedirect measurements and divides them into sevengroups: the entire sample, male, female, whitemale, black male, white female, and black female.Table 2 lists the means of the ratio data. Tabie 3lists the results of a two-way ANOVA used todetermine whether the values varied significantlyby gender and/or by race. The ratios for the rightand left sides were then pooled to increase thesample size, and the means are contained in Table4- An ANOVA was run on these ratios to deter-mine whether the differences within each variablesubgroup (ie, L:W of central incisors, lateralincisors, and canines) were significant (ie, whetherthe ratio of L:W of central incisors is the same sta-tistically as that for lateral incisors, canines, etc).The P values from this ANOVA are also listed inTable 4. Figure 4 graphically demonstrates theinterval of each ratio within each variable sub-group taken from Table 4. The ranges are extreme-ly narrow at the 95% confidence level.

The data indicate that the length of the anteriormaxillary teeth varied significantly by gender, withincisors of males longer than those of females, butnot by race. The maximum width of maxillarycanines varied by both gender and race; canines ofmales were wider than those of females andcanines of blacks were wider than those of whites.The maximum width of central incisors did notvary by gender or race.

ilume7. Numbers, 1994 413 The International leurrai of Prosthodontics

Selected Normalive Tootli Proponic

Table 2 Mean Values (in tnm) of Ratios Calculated From L and W Measurements of the Maxiiiary Anterior Te

SampleMaleFemaleWhite maleBiack maleWhite témaleBlack female

L:W right canine

Mean

1.211.241,151.261.231 181,12

SD

0.1290

0.11900,13940,15150.0468

L right central:L nght lateral

L:W right lateral

Mean SD

1.19 0.1498

1.19 0,14801.24 0,15491.23 0.15951,08 0,1179

L right centrai:L right canine

L:W right central

Mean

1,101,131.051.171,071,101,00

SD

0.11920,10930,11990,11030.07920.09000.1315

L right canine:L right laterai

L:W iefi centrai

Mean

1,121,161,051,171.131 071 02

SD

0.10570.08250,10880,07970,08320,11570,1011

Lieft centrai:L left laterai

L:W left lateral

Mean

1.191.221,151,241,191,251,05

SD

0.1677

0 16780.14230.19950.17520.0813

L left central:L left canine

L:W ieft canine

Mean

1.21

1,27

1.171,12

SD

0,1251

0.10890,1071

0,14420,0499

L left canine:L left iateral

Mean SD

SampleMale

1,18 0,1387 1,01 0,1180 1,16 1.19 0,1226 1.031,18 0.1646 1,00 0,1256 1.18 0,1069 1.21 0,1332 1.02

1,16 0,0B101,18 0.0883

FemaleWhite maleBlack maleWhite femaleBiack female

SampleMaleFemaleWhite maleBiack maieWhite temaieBiack female

1,181,241.101 201.15

0.08110,16690,11910,06960,0887

W right centrai:W nghl laterai

Mean

1,271.351 311.251.261,371,28

SD

0,10410,10580.09390,10090.11730.09610,0865

1,041,030.961,061,02

0,10210,11790,12970,11710.0873

W right central:Wrigh

Mean

1.111,091,141.101,081.131.15

t canine

SD

0,08040.06440.09690 06350.06720,10390,0943

1.141,191,141,141,12

0,07460.10490.10960,07570.0774

W right canine.W right lateral

Mean

1.141,141.141.191,141,121,11

SD

0.08950.08900.09270 09830.07360.06110.1131

1,181.211.191 151 20

0.10150.13360,13830,12420,0716

W left central:W iett iateral

Mean

1.271.261,281,271,241,331,23

SD

0,11750,13050,09250,07790.19040,09190,0621

1.051,021.011,061,04

0,08820,08280.07860 09600.0835

W left centrai:W iett canine

Mean

1.121.101,141.101,101,511,13

SD

0,07140.06230,07960,06080.06730.09300,0673

1.121,181,181.091.16

0-05900,09690,07590.06140,0426

W ietf canine:W ieft laterai

Mean

1.191.141,191,141.111.161,09

SD

0,08290,09140,06770.07750,11120.05850,0671

-L = TDe most apJcal portion ol tHe clinical crown to the nearest point in the mrddle Lhird of the incisai eflge. or cusp tip on the canineW = The greatest mesial to distal width of Ihe tootfi as measured wilh the calrper lips placed interproximally as far as Ihey wilf go.

Table 3 Two-way ANOVA Comparing Gender andRace for Each cf the Mean Values'

Value

L6L7L8L9LIOL11

W5W 7W8W9W10W11

GenderP value

.000,003.001,000.008,000

.ODD

.005,124.144.046.000

RaceP value

,740,184063

.579.700.939

,010,042031

,128,006.033

Vaiue

L:W6L:W7L:W8L W 9L:W10L:W11

L8 L7L8:L6L6:L7L9:L10L9:L11L11:L10

W8:W7W8:W6W6:W7W9:W10W9:W11W11:W10

GenderP vaiue

,013.353.021,000,242.002

.879

.173,296.390.174,044

.056

.040,884,353.040.807

RaceP value

,205.738.002,080.016.170

,005,081312.876,617439

,538.836,742091.740,085

'Conliaencin bold.

level ot ,01 was used. Statistically signiiicant P vatues are

The length-to-widfh ratios for the teeth were notaffected by race or gender. When comparinglengths; of adjacent anterior teeth there were noeffects by race or gender. When the maximumwidths of adjacent anterior teeth were comparedthere were no effects by race or gender. Therefore,race and gender affected the direct measurementssomewhat but did not affect the ratios.

Discussion

Direct measurements from casts provided valuesthat are "clinical," allowing soft tissue and adjacentteeth to affect measured values, unlike measure-ments on extracted teeth. When restoring dentitionsof patients, these factors must be taken into consid-eration because esthetics deals with perception andcomposition, not isolated or fragmented informa-tion. The values obtained in this study could beused clinically as one of many tools in fabricatingrestorations and restoring edentulous spaces.Additional research on tooth dimensions is neededto expand (he sample size and broaden the inclu-

cLed Normarive Toolh Proporlions

Table 4 Combined Ratios of Ihe Right and Left Sides for the Entire Sample

SDInterval at

95% contidence level

L:W caninesL:W lateralsL:W centrals

L central • L lateralL central : L canineL canine: L lateral

W central ; W lateralW centra l . W canineW canine : W lateral

1.2121.1921.109

1.1881.0211.279

1.27Q1.1131.145

0.1190.1490.104

0.109Q.0900.144

0.1040.0730.105

1.1801.1521.080

1.1590.9961.240

1,2421.0931.117

1.2451.2331.137

1.3161.0451.31B

1.2991.1331.174

<.OO1

<.OO1

<,001

•L W = Length-lo-width ralio for canines, lateral incisors, ard central incisors, respeclively.L:L = Ratio of lengtris of central inoisor to laleral incisor, central incisor to canine, and canne to lataral

incisor, respeotiuely.W:W = Ratio ot maximum widills.

F ig 4 Range of tt ie ratios torthe study samp le , at the 9 5 %contidence level.

Ratio Hange

II

II

I

II

c? .^^ ,'1^ . ^

! 7, Number 5, 1994 415 The Internalional lournal of ProstSodonlii

ctcd Normative Toalli Proportions

sion criteria. This would allow more reliable extrap-olation of ihe results to the general population.

These measured values may be useful in plan-ning treatment and executing clinical procedures.For example, maintaining the proper values forlength and width, and especially the comparativeratios, would be important in achieving an estheticresult for composite or porcelain veneers. For apatient with diastemas, these same ratios would beimportant in determining the correct restoreddimensions. For example, in most cases whenteeth are to be made wider, it is also necessary tomake them longer to maintain the proper dimen-sions. This is an important preoperative considera-tion, since longer teetb may not be estheticallypleasing in some patients. Crown lengtheningmight be the preferred method of establishing thecorrect proportions in patients whose occlusal rela-tionships preclude the addition of incisal length. Aknowledge of the clinical crown heights and L:Wratios is necessary to determine how much addi-tional crown length is needed and whicb methodshould be used.

Tbere were no significant differences amongratios based on race or gender (see Table 3¡. For thisstudy group one may conclude that ratios are con-stant. This is of interest because the direct measure-ments do vary with these same variables. Thecanine values are an example. The L:W ratio is 1.21for males and females, either black or white (seeTable 4). Figure 4 demonstrates graphically that theintervals of L:W ratios for the teeth studied are sonearly the same tbat for clinical purposes they maybe considered identical. Table 4 and Fig 4 show thatthe ratio of clinical lengths of central incisors com-pared to canines is 1:1, and that of canines or cen-tral incisors compared to lateral incisors is 1.21:1.Tbe maximum width comparisons indicate a valueof 1.27:1 wben central incisors are compared to lat-eral incisors, 1.11 for central incisors to canines,and 1.15 for canines to lateral incisors. The value of1.21:1 for comparison of central incisors to lateralincisors does not compare favorably witb the valueof 1.618:1, tbe golden proportion used in the discus-sion of esthetic relations."-'*'^ The canine-to-lateralincisor ratio in this study used tbe entire widtb of thecanine, wbereas the golden proportion comparisonsuse only that portion of tbe canine visible from tbefrontal aspect. A similar comparison was not madein this study.

When comparing the right and left sides of thearcb, the direct measurements were extremely close(usually within 0.1 mm). In several circumstancesthe results of the ANOVA differed for the samemeasurement or ratio when comparing the right

and left sides (Table 3), For example, W of tan'and lateral incisors, L:W of central incisors, anilcentral incisors to lateral incisors had stafstic.feTences on one side but not the other wben c - '

AZZCP The W of the lateral incisors and theT w of he ¿nines had differences when the rightan^l^ft were compared by gender. However, clmi-

callv these differences are insignificant.The data obtained in this study support some

aspects of the historical literature and refute others^In this study group, there were significant race- andeender-based differences. These findings agreewith anthropologie reports that maxillary caninesexhibit greater gender-based morphologic differ-ences than other teeth." In male baboons andother primates, the maxillary canines are muchlarger than those of the female. The data in tbisstudy generally support this relationship. The meanfigures for tooth length and maximum width in thispopulation correspond with those reported byKraus and Wheeler."^^" Tbe slight differences mightbe attributed to soft tissue influences, adjacentcontacts, and measurements that varied by asmucb as 0.2 mm.

Richardson--' made direct mesiodistal measure-ments of the anterior teeth of a limited black popu-lation using similar methods to tbe ones employedin tbis study. He reported measurements that weresmaller by an average of about 0.5 mm than themeasurements obtained in this Study (width has aslightly different definition in the two studies).Wben the width ratios are calculated from thevalues in Richardson's article, however, they areessentially the same as the ratios in this study.Preston'- measured tooth sizes on orthodontic castswith calipers and from computer-generated imagesof the casts, but did not report tooth dimensions,and made different comparisons than in this study.However, both studies found a poor correlationbetween tooth dimensions and the golden propor-tion, contrary to the theories of its proponents." "

Conclusions

Within the population studied and the samplesize available, the following conclusions may bemade based on the average values obtained fromthis sample:

1. The central incisors and canines were approxi-mately equal in length and were 20% longerthan the lateral incisors,

2. The central incisors were the widest teeth, 25%wider than the lateral incisors and 10% wide,than tbe canines.

The International Journal of Pr 416 ! 7, Nuniber s,

alive Tooih Proporlions

3, The length-to-widtb ratio of the canines and thelateral incisors were the same (approximately1.2:1), and the length-to-width ratio of centralincisors was 1.1:1,

4, There were gender-based differences in thelength of the six maxillary anterior teeth. Theteeth of males were significantly longer thanthose of females,

5, The maximum width of the maxillary caninesindicated significant gender and race differ-ences. The teeth of males were wider thanthose of females, and the teeth of blacks werewider than those of whites,

6, Ratios comparing length to width for eachtooth, widths of adjacent teeth, and lenglhs ofadjacent teeth did not differ statistically by gen-der or race. In this study population, the calcu-lated ratios may be considered representativefor all individuals.

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