Data from the

NATIONAL HEALTH SURVEY

An Assessment of

the Occlusion

of the Teeth of Youths

12-17Years

United States

Estimates of the distribution of selected major components of

occlusion among youths; the prevalence of degrees of malocclusion; the average Treatment Priority Index per youth by age, sex,

race, family income, education of head of household, and region

of residence; and a brief analysis of the relation of occlusal status

with a reported need for orthodontic care.

‘ DHEW Publication No. (HRA) 77’-1644

US. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE

Public Health Service

Series 11

Number 162

Health Resources Administration

National Center for Health Statistics

Rockville, Md. February 1977
Library of Congress Cataloging in Publication Data

Kelly, James E.

An assessment of the occlusion of the teeth of youths 12-17 years, United States.

(Vital and health statistics: Series 11, Data from the National Health Survey; no. 162)

(DHEW publication; no. (HRA) 77-1644)

Includes bibliographical references.

1. Malocclusion–United States–Statistics. 2. Youth–Dental care–United States–

Statistics. 3. Dental surveys–United States. I. Harvey, Ckir R., joint author. II. United

States. National Center for Health Statistics. 111. Title. IV. Series: United States. National

Center for Health Statistics. Vital and health statistics: Series 11, Data from the National

Health Survey, Data from the health examination survey; no. 162. V. Series: United States.

Dept. of Health, Education, and Welfare. DHEW publication; no. (HRA) 77-1644.

RA407.3.A347 no. 162 [RK523] 312’.0973s

ISBN 0-8406 -0073-9 [312’.3’047643] 76-16152

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Price $1.45

Stock No. 017-022-00529-8
NATIONAL CENTER FOR HEALTH STATISTICS

DOROTHY P. RICE, Director

ROBERT A. ISRAEL, Deputy Director

JACOB J, FELDMAN, Ph.D., Associate Director for Analysis

GAIL F. FISHER, Associate Director for the Cooperative Health Statistics System

ELIJAH L. WHITE, Associate Director for Data Systems

ANDERS S. LUNDE, Ph.D., Associate Director for International Statistics

ROBERT C. HUBER, Associate Director for Management

MONROE G. SIRKEN, Ph.D., Associate Director for Mathematical Statistics

PETER L. HURLEY, Associate Director for Operations

JAMES M. ROBEY, Ph.D., Associate Director for Program Development

ALICE HAYWOOD, Information Officer

DIVISION OF HEALTH EXAMINATION STATISTICS

ARTHUR J. McDOWELL, Director

JEAN-PIERRE HABICHT, M.D., Ph.D., Special Assistant to Director

JAMES E. KELLY, D.D.S., Dental Adviser

JEAN ROBERTS, Chief Medical Statistics Branch

ROBERT S. MURPHY, Chief Survey Planning and Developing ~ranch

COOPERATION OF THE BUREAU OF THE CENSUS

In accordance with specifications established by the National Health

Survey, the Bureau of the Census, under a contractual agreement, participated in the design and selection of the sample, and carried out the first stage

of the field interviewing and certain parts of the statistical processing.

Vital and Health Statistics-Series 11-No. 162

DHEW Publication No. (HRA) 77-1644

Library of Congress Cataihg Card Number 76-16152
Acknowledgment

The National Center for Health Statistics thanks Dr. James P. Carlos,

Associate Director for National Caries Program, National Institute of

Dental Research, for his assistance in planning the present report; Dr.

Ralph A, Frew and Janet A. Brunelle, National Caries Program, for the

program used to compute the Treatment Priority Index; and Coenraad

F. A. Moorrees, Professor of Orthodontics, Forsyth Dental Center, for

the photographs used to illustrate selected components of the

Treatment Priority Index (TPI).

...

Ill
CONTENTS

Page

Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. iii

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Findings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...2

ComponcntsofOcclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

VerticalOverbiteorOpenbite . . . . . . . . . . . . . . . . . . . . . . . . . .

OverjetofUpperorLowerIncisors . . . . . . . . . . . . . . . . . . . . . . .

PosteriorCrossbite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ToothDisplacementScore . . . . . . . . . . . . . . . . . . . . . . . . . . .

BuccalSegmentRelation . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TreatmentPriorityIndex. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DistributionofTPIScores. . . . . . . . . . . . . . . . . . . . . . . . . . . .

ScverityofMdocclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

MalocclusionSyndromes. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Avcragc TPIScore Associated With Selected Demographic Characteristics. . . . .

Age, Sex, and Race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Other Demographic Characteristics . . . . . . . . . . . . . . . . . . . . . . .

2

2

3

3

3

5

5

5

5

6

7

7

7

Additional Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...8

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...12

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...16

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...18

Listof Detailed Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...19”

Appendix I. Assessment of Occlusion and Training of Examiners . . . . . . . . . . 49

Procedures for Assessment of Occlusion . . . . . . . . . . . . . . . . . . . . . . 49

Calculation of Treatment Priority Index . . . . . . . . . . . . . . . . . . . . . 51

Training Examiners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...51

FORTRAN Program for Computing TPI Scores . . . . . . . . . . . . . . . . . . 53

Appendix II. Demographic and Socioeconomic Terms . . . . . . . . . . . . . . . . 56

Appendix III. Statistical Notes.. . . . . . . . . . . . . . . . . . . . . . . . ...57

The Survey Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...57

Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..58

Sampling and Measurement Error . , . . . . . . . . . . . . . . . . . . . . . . . 59

v
Page

Expected Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...59

SmallNumber s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...60

TestsofSignificance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Appendix IV. The Relation Between TPIScores and Orthodontists’ Ratings of the

Severity of Malocclusion . . . . . . . . . . . . . . . . . . . . . . . . . . ...61

SYMBOLS

Data not available --------------------------------------- ---

Category not applicable ------------------------------ . . .

Quantity zero --------------------------------------------- -

Quantity more than O but less than 0.05---- 0.0

Figure does not meet standards of

reliability or precision ---------------------------- *

vi
AN ASSESSMENT OF THE OCCLUSION

OF THE TEETH OF YOUTHS 12–17 YEARS

James E. Kelly, D. D. S., and Clair R. Harvey,

INTRODUCTION

During 1966-70, the Division of Health Examin;ttion Statistics conducted a survey that collcctcd information about the health of the U.S.

population aged 12-17 years.1 The survey was

the third of a series of Health Examination

Survc y programs which obtain statistical information about the health of selected segments of

the U.S. population. The conduct and operation

of the survey of youths were practically the

same as those of the two earIier surveys, one of

adults aged 18-792 and the other of children aged

6-11.2>3 Physicians, dentists, psychologists, and

technicians conducted examinations in mobile

cxamirmtion centers which visited 40 scientifically selected locations in 25 states.

The universe, or target population, from

which the sample of youths was drawn totaled

approximately 22.7 million (table III, appendix

III). It was defined as all noninstitutionalized,

civilian youths aged 12-17 years living in the

United States (including Alaska and Hawaii)

cxcqt those on lands reserved for the use of

American Indians, A probability sample of

approximately 7,500 was selected by a complex

scientific procedure so that statistically valid

cstinuites about the health of the Nation’s youth

could be made.

Each sttmple youth that participated in the

survey received the same examination. As in the

vwlier survey of children’s health, most of the

tests and measurements in the survey of youths

focused on factors related to biological and

psychological aspects of growth and developDivision of Health Examination Statistics

ment. A pediatrician examined the nose, eyes,

throat, ears, heart, and neuromuscular system of

each youth. The teeth and their supporting

structures were examined by a dentist, and tests

of intellectual development, school achievement,

and personality development were administered

by a psychologist. The examination ako included tests of vision, hearing, exercise tolerance, grip strength, and breathing capacity.

Blood pressure levels and electrocardiograms

were recorded as well as height, weight, and

several other body measurements.

The dental examination was given by seven

dentists who were employed at various times

during the survey. Teeth were classified as

sound, filled, decayed, filled-defective, and nonfunctional-carious. The absence of permanent

teeth and the presence of artificial teeth and

exposed root remnants were recorded. X-rays of

the teeth were not taken. An adjustable examining chair, a standard light source, and a mouth

mirror and explorer were used during the examination which usually lasted about 10 minutes.

During the dental examination selected components of the occlusion of the teeth, including

their alignment, were either noted or measured

and recorded. The procedure for assessing occlusion and the training received by the examining

dentists are described in appendix I. Among the

recorded variables were the following:

Vertical overbite or openbite

Overjet of the upper or lower incisors

Posterior crossbite

Tooth displacement

Buccal segment relation
At the close of the survey 90.0 percent of the

7,514 sample youths had been examined. With

respect to age, sex, race, geographic region,

population density, and population growth in

area of residence, the examined sampIe may be

regarded as closely representative of the population it was drawn from. It seems quite unlikely,

therefore, that nonresponse would appreciably

bias estimates based on the findings of the

survey.

This report contains estimates of the occurrence and distribution of selected components

of the occlusion of the teeth. It includes

national estimates of the number of youths with

normal occlusion and of the number with

various degrees of malocclusion. The relation of

occlusal status with age, sex, race, and other

selected demographic characteristics is examined, and the relation of occlusal status with a

reported need for orthodontic treatment is

briefly analyzed.

The Treatment Priority Index (TPI) was used

to assess the occlusion of the teeth. Selected

major components of occlusion are combined in

the TPI to give a single, weighted score indicating the severity of malocclusion present in

each youth. As measured by the index, occlusal

status may range from virtually ideal occlusion

(a score of O) to very severe malocclusion (a

score of 10 or more).

The TPI is an important outgrowth of the

research conducted by the Burlington Orthodontic Research Project of the University of

Toronto. It was developed to find out whether

preventive orthodontic treatment could reduce

the prevalence and the severity of malocclusion

in children. The proposed TPI was first described in the 1960 annual report of the

Burlington Orthodontic Research Centre.q Its

later development is described in a publication

of the National Center for Health Statistics.s

All five measurements needed for calculating

a TPI score could not be taken on every sample

youth’s teeth. Sometimes the teeth involved in a

measurement, and sometimes those involved in

more than one, were missing. At other times

none of the measurements could be taken,

usually because fixed orthodontic appliances

were in the way. If only one TPI component was

missing, a value for it was imputed by using the

procedure described in appendix III.

2

The estimated population represented by the

sample youths is shown in table III, appendix

III, by age, race, and sex. The estimated population is shown in each detailed table when it is

less than 22.7 million, which at the midpoint of

the survey was the total population of noninstitutionalized, civilian youths aged 12-17.

In the following text the findings for youths

are often compared with similar findings for

U.S. children aged 6-11. The estimates of the

occIusal status of the younger children were

based on measurements collected during the

sample survey conducted from 1963 through

1965. A

occlusion

1973.6

report on the assessment of the

of children’s teeth was published in

FINDINGS

Components of Occlusion

Vertical Overbite or Openbite

“Overbite” and “openbite” are terms that

describe the vertical relation of the upper

incisors with the lower incisors (appendix I).

With the upper and lower teeth resting together,

vertical overbite is present when the leading, or

incisal, edges of the upper anterior teeth overlap

those of the opposing lower ones. When that

relation is reversed so that the incisal edges of

the upper teeth lie above those of the lower

ones, openbite is present. The estimates in tables

1 and 2 apply to those youths with fully erupted

upper and lower incisors whose vertical relation

could be measured.

Only 5.2 percent of the youths have anterior

teeth in the openbite relation. An estimated

45.9 percent have overbite measurements of O-3

mm., which is considered the normal range, and

38.6 percent have measurements of 4-5 mm.

Overbites of 6 mm. or more, which may be

clinically significant, are present in 10.3 percent

of the youths. The numbers of male and female

youths with specified overbite and openbite

measurements are about the same.

Both the prevalence and the severity of

vertical overbite are associated with race. The

upper and lower incisors of about 96 percent of

the white youths, but of only about 84 percent
of the black youths, are in the overbite relation.

Severe overbites (figure 1), those measuring 6

mm. or more, are much more common in white

youths (11.7 percent) than in black youths (1.4

percent).

The openbite relation on the other hand is

more common in black youths than in white

ones—16.2 percent compared with 3.5 percent.

Proportionately more black than white youths

also have severe openbites (figure 2), which

often impair the function of the teeth and

adversely affect the youths’ appearances. For

example, about 10 percent of the black youths,

but only about 1 percent of the white youths,

have openbites that measure 2 mm. or more.

A small number of youths have upper and

Iowcr incisors that meet in an edge-to-edge

relation. The anterior vertical relation of their

teeth was recorded as being an openbite of Oand

a lower overjet of O.

Overjet of Upper or Lower Incisors

“Upper overjet” and “lower overjet” are

terms that describe the horizontal relation of the

upper incisors with the lower incisors (appendix

I). With the upper and lower teeth resting

together, upper overjet is present when the

upper anterior teeth lie in front of the opposing

lower ones. When that relation is reversed so

that the lower teeth lie in front of the upper

teeth, lower overjet is present. Overjet of the

upper incisors ranging from O to 5 mm. is

generally regarded as the normal horizontal

relation of the incisors. The estimates in tables 3

and 4 apply to youths with fully erupted upper

and lower incisors whose horizontal relation

could be measured.

An estimated 82.5 percent of the youths have

upper overjets that measure from O through 5

mm. About 15 percent have severe upper overjets that measure more than 5 mm. Overjet of

the lower incisors is a rare condition occurring in

only 2.5 percent of the youths. It is more

common in black youths (4.8 percent) than in

white youths (2.1 percent), but only about 1

percent of the youths of both races have severe

lower overjets–those greater than 1 mm. Both

severe upper and lower overjets may impair

biting and chewing and seriously affect the

appearance of children and adults (figures 3

and 4).

Posterior Crossbite

Approximately 12 percent of the youths have

at least one premolar or molar in crossbite to the

lingual (toward the tongue) of the opposing

lower teeth, and approximately 5 percent have

one or more in crossbite to the buccal (toward

the cheek). (See tables 5 and 6 and appendix I.)

Figure 5 illustrates the lingual crossbite relation.

Tooth Displacement Score

Crooked or makdigned teeth are perhaps the

most common sign of malocclusion; when present, they may impair both biting and chewing.

Extremely crowded front teeth are usually

shoved forward or backward from the normal

position and are always unsightly, often disfiguring. Hard to clean and to keep clean,

displaced and rotated teeth may be conducive to

the onset of gingivitis and periodontal disease.

Because both the degree of malalignment and

the number of makdigned teeth may adverseIy

affect one’s facial appearance and ability to bite

and chew food properly, the estimates in table 7

are not counts of displaced and malaligned teeth

but displacement scores. The displacement score

is the total number of teeth in minor malalignment plus twice the sum of those in major

ma.kdignment (appendix I). A tooth that is in

major makdignment is displaced 2 mm. or more,

or rotated 45° or more; a tooth in minor

malalignment is obviously either displaced or

rotated, but it is displaced less than 2 mm. or

rotated less than 45°. In the development of the

Treatment Priority Index, a tooth displacement

score of 4 was assumed to be of critical severity.

Figure 6 illustrates the appearance of someone

with severalbadly malaligned teeth.

Approximately 13 percent of the youths have

no obviously displaced or rotated teeth (table

7); about 37 percent have tooth displacement

scores of 3 or less, and the remaining youths

have scores of 4 or more. The scores for white

youths are generally higher than those for black

youths of the same sex.

3

Buccal Segment Relation

Neutroclusion is the normal anteroposterior

relation of the upper teeth with the lower. When

the lower molars interdigitate with the upper

molars in front of the normal position, the

relation is called mesioclusion and when they

interdigitate behind the normal position, it is

called distoclusion (appendix I).

Approximately 53 percent of the youths have

neutroclusion, 32 percent distoclusion, 14 percent mesioclusion, and 1 percent an asymmetrical relation (table 8). The buccal segment

relation was determined largely by observing the

interdigitation of opposing 6-year moku-s on

both the right and left sides of the mouth

(appendix I).

The prevalence of the types of buccal segment

relation, except the mixed (asymmetrical), varies

according to race. About 62 percent of the black

youths have neutroclusion as compared with

about 52 percent of the white youths. More

black youths than white youths are classified as

having mesioclusion–18.6 percent as against

13.0 percent. On the other hand, the percentage

of white youths (33.6 percent) with distoclusion

is significantly larger than the percentage of

black youths (18.0 percent) with that relation.

During the present survey as little as a

cusp-to-cusp deviation in the relation of the

lower buccal segment with the upper one was

classified as either mesioclusion or distoclusion,

even though the deviation occurred on one side

only. If the occlusion of the sample youths had

been classified by orthodontists, the results

would no doubt have been quite different from

those described above. The proportion of youths

classified as having mesioclusion seems especirdly

high; for, although 14 percent are classified as

having mesioclusion, only 2.5 percent have

overjet of the lower incisors.

Treatment Priority Index

Distribution of TPI Scores

Only 11 percent of the estimated 22.3 million

youths with TPI scores have zero scores (figure

7, table 9). About 54 percent have scores less

than 5, and 16 percent have scores of 10 or

more.

5

t

o

I I 1 I 1 I I I I I 1 I I I

01 234567S 9 10 11 12 130r

TPI SCORES

more

Figure 7. Percent of youths with specified TPI scores: United

States, 1966-70.

More black youths (14.7 percent) than white

youths (10.5 percent) have zero scores. Differences between the percentages of youths with

specified scores are not consistently associated

with either race or sex.

The percentages of youths with specified TPI

scores are distributed in table 10 according to

age and sex. There are no consistent differences

in the percentage distribution associated with

either age or sex.

Severity of Malocclusion

During the development of the Treatment

Priority Index, a scale ranging from O (virtually

classic normal occlusion) to 10 (very severe

malocclusion with treatment mandatory) was

arbitrarily selected to express the relative severity of malocclusion occurring in children and

youths.5 The scale was constructed with the

assumption that no score, or cutoff point, would

unerringly distinguish between children and

youths who need orthodontic care and those

who do not.

It should be noted that a given TPI score, like

the judgment rating of an orthodontist, does not

always reflect the same degree of clinical severity, because the weights and constants used to

calculate the scores for each major type, or

syndrome, of malocclusion are the same. But the

clinical interpretation indicated by ranges of the

index is much more reliable than individual

scores. Furthermore, since the TPI is highly

reproducible in the hands of trained examiners,

significant differences between the average

5
scores for large groups of people undoubtedly

reflect real differences in their occlusal status.T

To establish the scale for classifying children

or youths according to their relative need for

orthodontic treatment (case severity), six conditions or factors that may be associated with

malocclusion, including unacceptable appearance, impaired biting or chewing, and speech

defects, were taken into consideration.b The

clinical interpretation of TPI scores suggested by

Grainger is as follows:

Malocclusion

severity scale Interpretation

o Virtually classic normal occlusion

1-3 Minor manifestations and treatment need is slight

4-6 Definite malocclusion but treatment elective

7-9 Severe handicap, treatment highly

desirable

10 Very severe handicap with treatment mandatory

National estimates of the percentage of

youths according to case severity are shown by

sex and race in table 11. An estimated 11.0

percent are classified as having normal occlusion,

and 34.8 percent are classified as having only

minor manifestations of malocclusion. An estimated 25.2 percent have definite malocclusion

for which treatment is elective. The scores for

the remaining youths range from 7 through 10

or higher, with treatment “highly desirable” for

13.0 percent and “mandatory” for an additional

16.0 percent.

Significantly more black youths than white

youths have zero scores, as was previously

noted. The percentages of black and white

youths in the four other ranges of case severity

are about the same. The percentage distribution

of youths by case severity does not differ

consistently according to sex.

In the preceding nationwide survey of the

health of U.S. children aged 6-11 years, a higher

percentage of the black children (8.2) than of

the white children (5.0) were found to have TPI

scores of 10 or more. Although the difference

was not great, it was statistically significant.

Other differences, which have not been mentioned, between the occlusal findings on children and those on youths will be noted later,

and what is believed to cause most of them

(namely the teeth that erupt at about the age of

12) will be discussed.

Malocclusion Syndromes

Youths are distributed in table 12 according

to specified malocclusion syndromes and TPI

scores. The syndrome under which each youth’s

malocclusion is classified is determined by the

occlusal component that contributes the greatest

weight to his TPI score. When the weighted

tooth displacement score is the largest contributor, the youth’s malocclusion is classified under

one of two syndromes: maxillary expansion if

either distoclusion or buccal crossbite is present

or maxilkry “collapse “ if neither distoclusion

nor buccal crossbite is present (figure I, appendix I). It is worth noting that this classification

by type of syndrome is not a diagnosis of a

youth’s malocclusion but a rather crude description of the defect involved. The occlusal defects

of only those youths with TPI scores of 4.5 or

more are classified by type of syndrome.

Maxillary “collapse” is the most prevalent

syndrome, occurring in an estimated 4 million

youths, and lower overjet is the least prevalent,

occurring in only 34,000. The estimated

285,000 youths whose TPI scores have two or

more equally high weights are classified as

having a “mixed” s@rome.

TPI scores of 10 or more are most highly

associated with the lower overjet syndrome and

least highly with the maxillary expansion and

the upper overjet syndromes. About 91 percent

of the youths with the lower overjet syndrome,

but only about 24 percent with the maxillary

expansion syndrome and 18 percent with the

upper overjet syndrome, have scores of 10 or

more.

In children 6-11 years old the upper overjet

and the overbite types, not the tooth displacement types (maxillary “collapse” and maxillary

expansion), were the most common syndromes.

6
It is believed that this difference between the

findings of the two surveys is due to the

increased number of teeth that have erupted in

the older children.

Fewer youths (34,000) than children (76,000)

were found to have malocclusions classified

under the lower overjet syndrome. The lower

prevalence of that syndrome in youths than in

children may perhaps be explained by the fact

that children whose lower anterior teeth overjet

their upper teeth often seek orthodontic care as

early as possible.

Average TPI Score Associated With Selected

Demographic Characteristics

Age, Sax, and Race

The average, TPI score per person for U.S.

youths of all races and both sexes is 5.0 (table

13). The mean scores do not rise with increasing

agc, nor are there large, consistent differences in

the scores associated with either sex or race. The

average scores for youths are generally about

two points higher than the comparable ones for

children 6-11 years old.

Other Demographic Characteristics

Because teeth continue to erupt after age 12,

there is reason to believe that tooth displacement scores, and therefore TPI scores, increase

as youths grow older. In consequence, actual

and expected (age-adjusted) estimates of the

average TPI per youth are shown in the remainder of this section. The U.S. population

12-17 years has been classified by family income, education of head of household, and

geographic region, and any differences that

appeared in the mean TPI per child among

various groups were examined. For example, the

estimates for white males in families whose

income was within one of six income ranges

were examined to determine whether the mean

TPI score for a given income range differed

si~mificantly from those for other ranges. In

addition, mean scores per youth for all income

ranges were compared to determine whether the

TPI trended higher or lower with increasing

income. The comparisons were made among

youths of the same race and sex, and adjustment

was made for differences in the age distribution

of the youths within each income and education group and within each geographic region by

calculating age-adjusted values.

Expected (age-adjusted) values were calculated by weighting the age-sex-race specific mean

TPI per youth for the total U.S. population of

youths 12-17 years by the number of youths in

that age-sex-race group within specified ranges

of income or education. Actual and expected

values may differ by chance. But, when the

difference between them is statistically significant, one may conclude that the mean TPI of a

given sex-race-income group or a sex-raqeeducation group is excessively larger or smaller

than the mean of that sex-race group for the

United States and that this excess is independent

of age.

Because of the relatively limited number of

sample youths, sampling variability for specific

age groups is usually quite large. It is for this

reason that summary comparisons of actuzd and

expected values were preferred to a comparison

of mean age-specific values.

Family income and education of head of

household. –The average TPI per person is

shown by specified levels of family income in

table 14 and by specified levels of the educational attainment of the head of household in

table 15. There is no trend in the mean scores

associated with levels of either family income or

education of the head of household. It will be

noticed, however, that the scores for white

females from families with yearly incomes of

$15,000 or more and for those whose parents or

guardians have 17 years of formal education or

more are significantly low. The low scores for

those two groups are probably due to the

relatively large number of persons in them who

have had orthodontic treatment, as is reported

in the following section “Additional Findings.”

Geographic region of residence. –There are no

important differences between the average TPI

scores for youths associated with geographic

region of residence (table 16). The largest

difference between comparable scores occurs for

black females, with those in the South having a
score of 4.6 and those in the Midwest having a

score of 6.0. In the previous survey black girls in

the South also had the smallest average score,

but those in the Northeast had the largest.

At this point it may be well to comment

about the findings just described, because the

high percentage of U.S. youths with TPI scores

of 7 or more will probably raise questions about

the clinical interpretation of the scores. This is

especially so in view of the percentage of youths

(10.7) who, as is reported in the section “Additional Findings,” had been or were under orthodontic treatment at the time of the survey. A

study by the New York State Department of

Health and another by the National Center for

Health Statistics provide information that may

help answer many of the questions that arise

(appendix IV).

After examining 1,379 casts of the teeth of a

broadly representative sample of high school

students in upstate New York, 30 orthodontists

found that 4.4 percent of the casts were

examples of a “very severe handicap for which

treatment is mandatory” and that an additional

26.1 percent were examples of a “severe handicap for which treatment is highly desirable.” TPI

scores for the same 1,379 casts placed 11.3

percent in the highest treatment priority group

and 10.2 percent in the next highest group. In

the earlier New York study, two orthodontists,

who had much more time to arrive at their

judgments than the 30 orthodontists in the later

study, found that 14.4 percent of the casts, an

estimate that was believed to be “cautious,”

represented severe “handicapping” malocclusion. The study casts included none that were

taken after a child’s teeth had been straightened.s

Diagnostic standards for dental as well as for

medical conditions are based on the best judgment of experts selected from the relevant fields

or specialties of those professions. At least to a

certain extent, the standards that are adopted

are often arbitrary. Only too often the eventual

effects of not treating a condition, unless its

signs and symptoms are quite obvious, are not

well known; here, too, the experience and

insight of experts must be relied upon in

establishing norms for clinical practice.

The TPI was designed to reflect the clinical

judgment of qualified practitioners of orthodontics, a specialty of dental practice. The data

cited above and in appendix IV bear witness that

the index does by and large what it is meant to

do and that, all considered, it provides a

practical, economical, and acceptably accurate

means of screening large populations for severe

cases of malocclusion. Anyone, who for reasons

of his own finds it desirable to choose a higher

or lower cutoff score than 7 to decide whose

teeth may need to be straightened and whose

may not, can of course do so. The provision of

that option is another valuable feature of the

TPI.

Finally, it is worthwhile to note that classification by the TPI should never be considered an

adequate substitute for an orthodontic diagnosis. For one thing, the TPI takes into account

only the relation of the teeth with one another.

An orthodontic diagnosis, however, also takes

into account facial proportions and the relation

of the teeth with the underlying bone, both of

which are important in arriving at an accurate

diagnosis and in deciding what treatment, if any,

is indicated for particular cases. In short, the

appropriate use of the TPI is in epidemiological

studies, whereas that of the orthodontic diagnosis is in clinical practice.

ADDITIONAL FINDINGS

Additional information about the health of

the sample youths was collected by selfadministered questionnaires, including one that

was filled out by the youths’ parents and

another by the youths themselves. The questionnaire for the parents, Medical History of Youth,

was left in each household that contained a

sample youth. The questionnaire for the youths,

Health Habits and History, was answered while

the youths were in the examination center.

Members of the survey staff reviewed the answers on each questionnaire, making certain that

all applicable questions had been fully answered

and that the responses on it were consistent with

one another.

Information from the parents. –The following

8
questions were included on the questionnaire

answered by the parents:

Have his (her) teeth been straightened or have

bands been put on them?

tl Ycs ❑ No

If no:

a. Do you think they need straightening?

❑ Yes ❑ No

b. Has a dentist said they need straightening?

❑ Yes ❑ No ❑ Don’t know

On the basis of the parents’ responses, it is

estimated that 10.7 percent of the youths, 2.4

million in all, have had orthodontic treatment

(table 17). The percentage that have ever had

their teeth straightened increases steadily with

advancing age, rising from 7.4 percent of those

12 years old to 13.3 percent of those 17 years

old. More girls (11.8 percent) than boys (9.6

percent) have been under orthodontic treatment

at one time or other.

About 12 percent of the youths that have not

had orthodontic treatment were reported by

their parents to need it (table 18). More white

females (13.3 percent) than white males (10.9

percent), black females (9.7 percent), or black

males (9.3 percent) were reported to need their

teeth straightened.

The percentages of youths reported to need

orthodontic treatment are shown by race and

family income in table 19. The estimates show

no trend associated with increasing family income for either white or black youths.

The parents of only 7.0 percent of the youths

reported that dentists have said their children’s

teeth need to be straightened. But more than

half of the parents who think their children’s

teeth need to be straightened reported that

dentists have said so (table A). The percentages

of youths whose teeth need to be straightened,

according to their parents, and whose parents

answered “yes” when asked “Has a dentist said

they need straightening?” do not differ significantly according to the sex of the youths.

Only about 1 percent of the youths whose

teeth according to their parents do not need to

be straightened have been told otherwise by

dentists. The percentages of youths so reported

do not differ according to sex (table B).

Table 20 shows the average TPI score per

person for youths whose teeth have not been

straightened according to whether or not their

parents reported that they need to be straightened and by sex and race. The average TPI for

youths of all races and both sexes with a

reported need for straightening (8.2) is significantly higher than that (4. 7) for other youths of

comparable sex and race. The differences between the average TPI scores for those reportedly

needing straightening and those reportedly not

needing it are about the same for all other

comparable sex-race groups.

Table 21 shows the average TPI scores per

person for youths whose teeth have not been

straightened according to whether or not dentists have ever said they need to be straightened

and by sex and race. The estimates are about the

Table A. Percent distribution of youths aged 12-17 years whose teeth need straightening (according

to parents), by whether or not dentists said so, according to sex

sex Yes No Not reported Yes No Not reported

Percent distribution Standard errors

Both sexes . . . . . . . . . . . . . . . . . . . 54.5 44.4 1.1 2.55 2.64 0.39

Male . . . . . . . . . . . . . . . . . . . . . . . . . . 55.8 42.5 1.7 3.73 3.76 0.69

Female, . . . . . . . . . . . . . . . . . . . . . . . 53.5 46.0 0.5 2.70 2.73 0.36

9
Table B. Percent distribution of youths aged 12-17 years whose teeth do not need straightening (according to parents), by whether or not dentists have said so, according to sex

Sex Yes No Not reported Yes No Not reported

Percent distribution Standard errors

Both sexes.........,.. . . . . . . . 0.7 99.2 0.1 0.10 0.11 0.05

Male . . . . . . . . . . . . . . . . . . . . . . . . . . 0.8 99.1 0.1 0.16 0.19 0,06

Female . . . . . . . . . . . . . . . . . . . . . . . . 0.6 99.2 0.2 0.17 0.18 0.07

same as the corresponding ones in table 20. The

average scores for white girls reported by their

parents to need their teeth straightened (7.6)

and for those who have been told by dentists

that their teeth need to be straightened (7.8) are

lower than the corresponding scores for white

boys–8.9 and 9.5, respectively. This suggests

that, when deciding whether or not children and

youths need orthodontic treatment, the parents

and dentists of white youths have one set of

standards in mind for girls and another, a slightly

lower one, for boys. On the other hand, apparently neither the parents nor the dentists of

black youths make such a distinction.

The average TPI per person for youths whose

teeth have been straightened is lower than that

for all other youths–4.l compared with 5.1

(table 22). The same difference occurs for all

sex-race groups except black females, where the

sampling variability is especially large. If, as

would seem likely, the TPI scores of youths who

have had orthodontic treatment were about the

same before they were treated as those of the

youths who have not had treatment but are

thought to need it, the average decrease in TPI

scores following treatment (about 4 points) is

convincing evidence of the effectiveness of

orthodontic correction.

Information from the youths. –The following

question was included on the

answered by the sample youths:

Do you think your teeth need

❑ Yes ❑ No ❑ Don’t know

questionnaire

straightening?

The estimates based on the answers to it are

shown in table 23. About 18 percent of the

10

youths whose teeth have not been straightened

answered “yes.” This is a fairly large increase

over the percentage that parents think need

orthodontic treatment. The percentages of both

boys and girls that think so are about the same.

The estimates show no consistent differences

associated with age, nor is there a significant

difference between the percentages of white and

black youths that think their own teeth need to

be straightened (table C).

As shown in table D, the scores for the youths

who answered “yes” are lower than the ones for

the youths whose parents or dentists reported a

need for straightening but, like the other scores,

they are within the 7-9 range, which is interpreted as “Severe handicap, treatment highly

desirable.” This indicates that, speaking generally, youths and their parents are not bad judges

of whether or not someone needs orthodontic

treatment.

The relation of a reported need for orthodontic treatment with ranges of TPI scores. –The

estimates in table E are the percentages of

youths of all races whose teeth were reported to

need straightening by parents, dentists, or the

youths themselves, according to ranges of TPI

scores. The ranges of scores are those which

Grainger found agreed well with the clinical

interpretation of TPI scores described earlier in

the section “Severity of Malocclusion. ”

Most youths whose teeth are thought to need

straightening by all three groups of respondents

are in the two highest treatment priority classifications, 7-9 and 10 or more. An estimated 54.0

percent of those who think their own teeth need

to be straightened and 59.0 percent of those

reported by their parents to need their teeth
Table C, Percent distribution of youths aged 12-17 by whether or not their teeth need to be straightened

(self-reported need), according to race and sex, with standard errors: United States, 1966-70

Self-reported need for tooth straightening

EIEIEiE

Standard errors

Race and sex Yes ] No I Don’t know

White Percent distribution

Bothsexes . . . . . . . . . . . . . . . . . . . . 1800 I 74.5 7.5

7.1

8.1

8.9

0.47 0.73 0.42

Male, . . . . . . . . . . . . . . . . . . . . . . . . . .

Female, . . . . . . . . . . . . . . . . . . . . . . . .

17.6 75.3

18.3 73.6

20.9 7.02

0.55

0.90

1.44

0.90

1.05

2.07

0.53

0.62

1.48

Black

Bothsexes . . . . . . . . . . . . . . . . . . . .

L

20.3 71.0

21.5 69.5

Male, . . . . . . . . . . . . . . . . . . . . . . . . . .

Female . . . . . . . . . . . . . . . . . . . . . . . . .

8.7

9.0

1.48

2.24

1.94

2.74

1.19

2.17

Table D, Average Treatment Priority Index (TPI) per person for youths aged 12-17, bywhether ornot their teeth

need tokstraightened (self-repotied need), race, andsex, with standard errors: United States, 1966-70

Race and sex

All races

Bothsexes . . . . . . . . . . . . . . . . . . . .

White

Doyou think your teeth need straightening?

Yes No Yes No Don’tknow

I

Don’tknow

Average TPI scores Standard errors

7.7 4.4 6.0

7.7 4.5 6.2

8.1 4.6 5.9

7.3 4.4 6.4

7.6 4.0 5.3

7.6 3.8 4.5

7.6 4.2 6.0

0.24 0.15 0.31

Bothsexes . . . . . . . . . . . . . . . . . . . .

Male, ., ., ., ..,,...,. . . . . . . . . . . .

Female . . . . . . . . . . . . . . . . . . . . . . . . .

Black

0.30 0.18 0.36

I I

0.34

0.33

0.17

0.21

0.36

0.52

Bothsexes . . . . . . . . . . . . . . . . . . . . 0.43 0.16 0.62

Male, .,, , .,, . . . . . . . . . . . . . . . . . . .

Female . . . . . . . . . . . . . . . . . . . . . . . . .

11
Table E. Percent distribution of youths aged 12-17 years by Treatment Priority Index (TPI), according to who

reported need for youths’ teeth to be straightened, with standard errors: United States, 1966-70

I II Treatment Priority Index Range

Need for straightening

Total

reported by:

o 1-3 4-6 7-9 ‘0 o 1-3 4-6 7-9

10

or more or more

Percent distribution I

Standard errors

Parents . . . . . . . . . . 100.0 1.8 16.4 22.8 22.9 36.1 0.44 1.77 2.26 1.63 3.11

Dentists . . . . . . . . . . 100.0 1.6 13.4 21.5 23.8 39.7 0.51 2.26 1.85 2.03 3.40

Youths . . . . . . . . . . 100.0 2.4 20.1 23.5 20.1 33.9 0.49 1.35 1.68 1.13 2.35

straightened have scores of 7 or more. The best

agreement between high scores and a reported

need for orthodontic treatment is, as would be

expected, for youths whose teeth dentists have

said need to be straightened. In that group 63.5

percent have scores of 7 or more (table E).

A high percentage of the youths reported by

either their parents or themselves as not needing

orthodontic treatment are in the lower treatment priority groups-O, 1-3, and 4-6. Of the

youths who according to their parents do not

need orthodontic treatment, 74.1 percent have

scores ranging from O through 6, and of those

who think their own teeth do not need to be

straightened 76.7 percent have scores in the

same range.

DISCUSSION

The conditions generally classified as malocclusion occur when various relations of the teeth

either deviate from the norms or are in disharmony with one another. The occlusion and

alignment of teeth range from what is considered optimal to very severe dislocations or

disharmonies that anyone would confidently

classify as malocclusion. But between those

extremes there is a broad, ill-defined area of

occlusal variations where arbitrary judgments

must be made in deciding how severe an occlusal

defect may be before it ought to be corrected.

Table F contains estimates of the number and

percentage of youths with occlusal defects that

were singled out because their nature or severity

probably indicates a need for treatment. It

seems reasonable to believe that the 10.2 million

youths (about 1 in every 2) with the listed

defects need at the least further orthodontic

evaluation and that a substantial number would

be considered by orthodontists as well asby the

youths themselves to need treatment. The same

youths may be included in more than one

category.

Some of the estimated 201,000 that have

impinging bites urgently need attention. This

condition occurs when the lower incisors make

contact with or bite into the soft tissue of the

palate. Impinging bites in youths 12-17 years

can be corrected only by orthodontic treatment.

Like the other conditions in the list, they may

interfere with biting or chewing. (NOTE .—The

number of youths with impinging bites is probably underestimated. Because the front part of

the palate is hard to see when the teeth are

closed together, it is often hard to determine

whether the lower teeth actually touch the

paIate or only seem to touch it, and, when in

doubt, the examining dentist was instructed not

to record an impinging bite as being present.

Many of the estimated 201,000 youths for

whom impinging bites were recorded had indentations on their palates caused by the lower

teeth and some had either inflamed or bleeding

palatal mucosa.)

Several differences between the estimates in

this report and those in the earlier one about the

occlusion of children aged 6-11 have already

12
Table F. Numkw nnd Dcromt of youths aged 12-17 and children aged 6.11 with high priority for orthodontic treatment, by specified malocclusion findings and race: United States, 1966.70 and

1963.65

Finding and race

Youths 12-17 years Children 6.11 years

Number

in

housands

Percent

~f those

Number

in

housands

Percant

of those

neasured

201 0.9 711 4.0

192

9

1.0

0.3

1.5

1.4

1.8

0.1

697

31

261

224

55

24

20

665

4.6

1.2

1.1

1.1

1.7

0.1

0.1

2.8

334

266

54

22

19

3

0.1

0.1

7,368 32.5

6,544

776

2,896

33.5

26.7

13.0

571

52

1,542

2.8

1.6

6.7

2,492

365

13.0

12.2

16.0

16.2

15.2

10.3

1,314

221

975

755

206

1,169

8.7

8.7

5,5

5,0

8.2

6,6

3,564

3,106

454

2,281

2230 11.7

1.4

2.3

1.2

10.1

8.0

1,147

20

443

211

244

1,672

7.6

0.8

2.5

1.4

9,6

9.4

42

54)9

229

300

1,783

1,611

166

8.4

5.5

0.9

0.8

1.2

1.471

201

142

121

15

9.7

7.9

0.8

0,8

0.6

201

153

36

13
been mentioned. At this point it seems appropriate to pursue the matter further and to suggest

what may have caused some of the differences.

The number and percent of youths and of

children with specified malocclusion findings are

compared in table F. It will be noticed that only

one condition, “tissue impingement,” is not as

common in youths as in children. The lower

estimate for youths suggests that many children

with impinging bites have orthodontic treatment

before age 12.

Many more youths (32.5 percent) than children (2.8 percent) have tooth displacement

scores of 7 or more, an increase undoubtedly

due in large part to the teeth that erupt as

children grow older. For example, 12-year-old

boys and girls average 4.0 and 2.8 more teeth,

respectively, than 1l-year-old children of the

same sex; and 13-year-olds average 5.7 and 3.8

more, respectively. Since, in general, the higher

the displacement score, the higher the TPI, a

greater percentage of youths (29.0) than children (14.2) also have high TPI scores.

Estimates of the prevalence of the remaining

occlusa.1 defects differ either not at all or only

slightly with age, which indicates that the

eruption of teeth after age 11 has little or no

effect on them. Then, too, it should be borne in

mind that youths who, when younger, had

occlusal defects may no longer have them owing

to orthodontic treatment.

It is worth additional comment that the

percentages of children and youths with openbites of 2 mm. or more are about the same.

Longitudinal studies have indicated that openbites in some children tend to improve spontaneously with advancing age. But the nearly equal

percentages of children and youths with severe

openbites suggest that spontaneous improvement of this defect may not occur as often as

some studies have,indicated.

In view of the high prevalence of crowded

teeth in U.S. children and youths, it might be

well to call attention to certain trends that have

taken place in the type of dental service children

receive and in the number and frequency of

dental visits they make. For it seems quite likely

that these trends have resulted in an increase in

the prevalence of malocclusion due to crowded

teeth.

There has been since 1958 only a small

increase in the average number of dental visits

by children aged 5-14 years-from 1.8 visits per

child to 2.0 per child in 1973.931° But of all

dental visits by children 5-14 years old, the

percentage for fillings declined from 50 in 1958

to 41 in 1964 and to 27 in 1971.9-11 Over the

same period the percentage of visits for extractions showed a smaller decline–from 12 to 9

percent.

As for the trend in the volume and frequency

of visits, proportionately more children are

visiting their dentists now than before, and

proportionately more are visiting them oftener.

From 1958 to 1969 the percentage of children

5-14 years old that had never visited a dentist

fell from 28 to 18, while the percentage with

visits during the past year rose from 48 to

59.12-18 By 1973 only 15 percent had never

visited a dentist, and 63 percent had visited one

within the past year.10

In short, the trends in dental services and

visits strongly suggest that the incidence of

tooth decay in children has been steadily falling

for the past decade or so, no doubt largely

because of the increase in the number of

communities that have added fluoride to their

water supplies. They further suggest that increasingly more children with decayed teeth

have them filled rather than extracted. If this is

true, increasingly more have had less room to

accommodate the teeth that erupt as they grow

older, a result that would increase the prevalence

of malocclusion due to crowded teeth.

Whereas the percentage of visits for fillings

and extractions has decreased, the percentage

for tooth straightening has more than doubled–

from 9 percent of all visits in 1958 by children

aged 5-14 years to 24 percent of all visits in

197l.g~l0 Thus it seems quite likely that increasingly more children have had their teeth

extracted not as a result of decay but as a part

of orthodontic treatment—that is, to provide

more room for the remaining teeth. Based on

the present survey findings, the estimated number of youths 12-17 years that have had “orthodontic extractions” is about 500,000. Comparable estimates for earlier years are not available.

The estimates in this report indicate that

there is a high prevalence of malocclusion in

14
U.S. youths aged 12-17 years. They further

indicate that the need for orthodontic treatment

is widespread and not exclusively associated

with any of the major demographic characteristics used to class the population. It is true for

youths as it was for children 6-11 years that

s~vere deviations of some occlusal components

such as overbites and openbites are associated

with race. But, perhaps more important, the

average TPI per person, excepting only that for

white girls whose families earn $15,000 or more

yearly, does not differ greatly according to age,

sex, race, family income, education of head of

household, or region of residence. The exception

noted for white girls in high-income families is

probably due to the large number of them who

have had orthodontic treatment.

Previous findings on U.S. adults aged 18-79,

U.S. children aged 6-11, and U.S. youths aged

12-17 have shown that the status of dental

health is closely associated with certain demobwaphic characteristics, especially family income

and educational attainment. For instance, the

average number of filled teeth per person increased from a low of 1.6 for youths whose

families have yearly incomes of $2,999 or less to

a high of 5.4 for those whose families have

incomes of $15,000 or morel 4 By contrast, the

average number of decayed and missing teeth

per person declined from 3.9 for youths in

families with the lowest incomes to 1.0 for those

in families with the highest. The same trends

also prevailed in both adults and children.1 SJ 6

The estimates in table 24 and figure 8 show

the close association that exists between the

receipt of orthodontic care and family income.

An estimated 107 per 1,000 youths of all

income groups were reported to have had their

teeth straightened. The number that have had

orthodontic treatment increases steadily with

rising family income from a low of about 20 per

1,000 of those whose families earn less than

$3,000 yearly to a high of about 290 per 1,000

of those whose families earn $15,000 or more.

Oddly enough, in families with the highest

incomes, the percentage of youths that have had

orthodontic treatment is the same as the percentage of all youths classified according to the

TPI as having either a “severe handicap, treatment highly desirable” or a “very severe handicap with treatment mandatory.”

300

250

200

50

0

All Under $3,000- $5,000- $7,000-$10,000-$15,000.

incomes $3,000 $4,999 $6,999 $9,999 $14,999 or more

FAMILY INCOME

Figure 8. Number per 1,000 youths reported to have had their

teeth straightened, by annual family income: United States,

1966-70.

Whether or not the teeth of children 6-11

years old had been straightened was also closely

associated with the yearly income of their

families.6

The cost of orthodontic treatment, compared

with that of other dental services, is high

because most cases require many visits spread

over a period of months or sometimes years. But

compared with the lifetime cost of all dental

services received by most Americans, orthodontic treatment is not as expensive as it

otherwise seems to be. This statement is true

because orthodontic services, unlike those for

other dental conditions (examinations and Xrays, cleanings, fillings, extractions and the like),

are rarely needed more than once during a

person’s lifetime.

To ease the burden of paying a substantial fee

for services all at one time, most orthodontists

require only a part of their fees when they begin

to treat new patients and the balance in monthly

installments during the expected period of treatment. Nevertheless, poor families still cannot

afford orthodontic treatment for those of their

children who need it, and many middle-income

families either cannot, or feel that they cannot,

afford it for theirs.

The cost of orthodontic services received by

the children of low-income families has undoubtedly been paid largely or wholly by

15
third-party programs. Most fees for orthodontic

treatment, however, are out-of-pocket expenses

borne entirely by patients or their families. For

example, 1 in 2 of the orthodontists responding

to a questionnaire mailed in 1974 by the

American Association of Orthodontists (AAO)

to its active and associate members indicated

that less than 10 percent of his practice was

funded by third-party programs, and only 1 in

100 indicated that his practice was funded more

than 50 percent by such programs.1 T If significantly more children from poor families are to

have the orthodontic treatment they need, funds

from third-party programs for orthodontists’

fees will have to be greatly increased.

It seems obvious that the cost of orthodontic

treatment is not the sole reason why many

youths who could benefit from having their

teeth straightened do not. Estimates shown

earlier indicate that about 1 in 3 youths has a

severe malocclusion and that an additional 1 in 5

has an occlusal defect, such as deep anterior

overbite, that should be clinically evaluated by

an orthodontist to determine whether it ought

to be corrected. Yet the parents of only about 1

in 10 think their children’s teeth need to be

straightened, and only about 1 in 5 youths

thinks his own teeth need to be straightened.

Many parents and youths are apparently either

unaware of the manifestations of malocclusion

or else of the benefit of having orthodontic

treatment when it is needed. It also seems

apparent that many dentists in general practice

do not recommend orthodontic consultations

for their patients as often as they should.

Are there enough orthodontists in the country to treat all those whose teeth need to be

straightened? Not if everyone with malocclusion

should seek treatment within a fairly short

period–an event that is, of course, not very

likely to happen. But the fact of the matter is

that recent demand for orthodontic treatment

has fallen far short not only of the need for

treatment but of the capacity of orthodontists

to provide treatment. In response to a question

asked during the AAO’S 1974 survey of its

membership, 39 percent of those responding ~

reported that they “need more work,” 56

percent that they were “moderately busy,” and

only 3 percent that they were “overIoaded.”

In 1976 approximately 6,450 members of the

AAO were living in the United States and

practicing orthodontics.18 An unknown number

of other orthodontists, who do not belong to

the AAO, also treat orthodontic patients. In

addition, some general practitioners and pedodontists provide orthodontic services for their

patients, treating perhaps as many as 1 in every

4 orthodontic patients , according to the AAO,

in certain sections of the country.1 g

The AAO is deeply concerned about what

may well be a growing oversupply of orthodontic specialists. The number entering practice

each year ranges between 320 and 350, an

increment that far exceeds the number of

orthodontists dying or retiring each year. Contributing to the AAO’S unfavorable manpower

projection is the declining U.S. birth rate, which

resulted in an estimated 3.1 million births in

1975 compared with 3.6 million in 1966.1 g~z”

And unless the demand for orthodontic treatment increases rapidly over the next few years,

the AAO’S projections on patient load indicate

that in 1982 most orthodontists will be working

at much less than their full capacity.1 T

SUMMARY

The estimates in this report are based on

findings of dental examinations conducted during 1966-70 on 6,768 youths, 90 percent of a

probability sample of 7,514 youths representative of approximately 22.7 million noninstitutionalized U.S. youths aged 12-17.

The distribution among youths of several

major components of occlusion was presented.

The components were:

Vertical overbite or overbite

Overjet of the upper or lower incisors

Posterior crossbite

Tooth displacement

Buccal segment relation

The prevalence and severity of malocclusion,

as they are measured by the Treatment Priority

Index (TPI), were also estimated. In addition,

the average TPI per person was examined to

determine whether occlusal status is associated

with various demographic characteristics such as

age, sex, race, and family income. Finally, the

relation of the occlusion of the youths’ teeth

with a reported need for orthodontic treatment

was briefly amdyzed.

16
Among the principal findings are the following:

1. Many more youths have vertical overbites

than openbites–94.8 percent as against 5.2.

An estimated 10.3 percent have severe

overbites measuring 6 mm. or more, and

3.4 percent have severe openbites measuring 1 mm. or more.

2. Most youths, about 98 percent of them,

have upper overjets, and about 15 percent

have severe overjets measuring 6 mm. or

more. The remaining youths have lower

overjets, but only about half of them or 0.9

percent of all youths, have severe overjets

measuring 1 mm. or more.

3. About 12 percent of the youths have at

least one premolar or molar in crossbite to

the lingual (toward the tongue) of the

opposing lower teeth, and about 5 percent

have at least one in crossbite to the buccal

(toward the cheek). About 13 percent of

the youths have no obviously displaced or

rotated teeth; about 38 percent have tooth

displacement scores of 3 or less, and the

remaining youths have scores of 4 or more.

4. About 54 percent of the youths have

neutroclusion, the anteroposterior relation

of the upper with the lower back teeth

characteristic of normal occlusion. About

32 percent have distoclusion, 14 percent

mesioclusion, and 1 percent an asymmetrical relation. Proportionately more black

(62 percent) than white youths (52 percent) have neutroclusion and proportionately more (19 percent compared with 13

percent) have mesioclusion. On the other

hand, more white (34 percent) than black

youths (18 percent) have distoclusion.

5. Consistent differences in the average TPI

per youth are not associated with age, sex,

race, family income, education of the head

of household, or geographic region. But the

average scores for white females from families with yearly incomes of $15,000 or

more, and for those whose parents or

guardians have 17 years of formal education or more, are significantly low.

6. According to classification by the TPI, 11

percent of the youths have normal occlusion, and 35 percent have only minor

manifestations of malocclusion. About 25

percent have definite malocclusion for

which treatment is considered to be elective. Scores for the remaining youths range

from 7 to 10 or more, with treatment

“highly desirable” for 13 percent (2.9

million) and “mandatory” for an additional

16 percent (3.6 million). Included among

those who urgently need further orthodontic evaluation are 201,000 whose lower

front teeth either contact the palate or bite

into it.

7. An estimated 10.2 million youths have

specified occlusal defects, such as large

anterior overbites or openbites, that should

be evaluated by orthodontists to determine

whether or not treatment is needed. The

youths include 201,000 whose lower front

teeth contact the palate or bite into it.

8. An estimated 107 per 1,000 youths, 2.4

million in all, have had their teeth straightened. The percentage that have ever had

orthodontic treatment increases steadily

with age, rising from 7.4 percent of those

12 years old to 13.3 percent of those 17

years old. More girls (11.8 percent) than

boys (9.6 percent) have had treatment. The

number ever treated is strongly associated

with family income, ranging from a low of

about 20 per 1,000 of those whose families

earn less than $3,000 yearly to a high of

about 290 per 1,000 of those whose

families earn $15,000 or more.

9. About 12 percent of the youths whose

teeth have not been straightened are

thought by their parents to need orthodontic treatment. More white females (13.3

percent) than white males (10.9 percent) or

black females (9.7 percent) or black males

(9.3 percent) are reported to need their

teeth straightened. The average TPI per

person for youths reported to need their

teeth straightened (8.2 ) is about twice as

high as that for comparable youths reported not to need their teeth straightened

(4.7). When asked whether they thought

their own teeth need to be straightened, an

estimated 18 percent of the youths

answered “yes.”

17
1National Center for Health Statistics: Plan and

operation of a health examination survey of U.S. youths

12-17 years of age. Vital and Health Statistics. PHS Pub.

No. 1000-Senes l-No. 8. Public Health Service. Washington, U.S. Government Printing Office, Sept. 1969.

‘National Center for Health Statistics: Plan and

initial program of the Health Examination Survey. Vital

and Health Statistics. Series l-No. 4. DHEW Pub. No.

(HRA) 74-1038. Health Resources Administration.

Washington, U.S. Government Printing Office, Nov.

1973.

3National Center for Health Statistics: Plan, operation and response results of a program of children’s

examinations. Vital and Health Stat&tics. PHS Pub. No.

1000-Series l-No. 5. Public Health Service. Washington.

U.S. Government Printing Office, Oct. 1967.

4Burlington Orthodontic Research Centre: Progress

Report No. 5. Faculty of Dentistry, University of

Toronto, 1960. (mimeographed)

5National Center for Health Statistics: The Orthodontic Treatment Priority Index. Vital and Health

Statktics. PHS Pub. No. 1000-Series 2-No. 25. Public

Health Service. Washington. U.S. Government Printing

Office, Dec. 1967.

6National Center for Health Statistics: An assessment

of the occlusion of the teeth of children 6-11 years,

United States. Vital and Health. Statistics. Series 1l-No.

130. DHEW Pub. No. (HRA) 74-1612. Health Resources

Administration. Washington. U.S. Government Printing

Office, Nov. 1973.

7Carlos, J.P.: Evaluation of indices of malocclusion.

Transactions of the Second F.D.I. Conference on Oral

Epidemiology, Epidemiological Assessment of Dentofacial Anomalies, Vol. 20, No. 4. Oct. 1969. pp.

606-615.

8Ast, D-B., CMOS, J.P., and Cons, N.C.: The Prevalence and characteristics of malocclusion among senior

high school students in upstate New York. Am. J.

Orthod. 51:437-445, June 1965.

9U.S. National Health Survey: Dental cue, volume of

visits, United States, July 195 7-June 1959. PHS Pub.

No. 584-1315. Public Health Service. Washington. U.S.

Government Printing Office, Apr. 1960.

1‘National Center for Health Statistics: Unpublished

data from the Health Interview Survey.

11 National Center for Health Statistics: Volume of

dental visits, United States, July 1963-June 1964. Vital

and Health Statistics. PHS Pub. No. 1000-Series 10-No.

23. Public Health Service. Washington. U.S. Government

Printing Office, Oct. 1965.

12 U.S. National Health Survey: Dental care, interval

and frequency of visits, United States, July 1957-June

1958. PHS Pub. No. 584-1314. Public Health Service.

Washington. U.S. Government Printing Office, March

1960.

13 National Center for Health Statistics: Dental visits,

volume and interval since last visit, United States, 1969.

Vital and Health Statistics. Series 1O-NO. 76. DHEW

Pub. No. (HSM) 72-1066. Health Services and Mental

Health Administration. Washington. U.S. Government

Printing Office, July 1972.

14National Center for Health Statistics: Decayed,

missing, and filled teeth among youths 12-17 years,

United States. Vital and Health Stattktics. Series 1l-No.

144. DHEW Pub. No. (HRA) 75-1626. Health Resources

Administration. Washington. U.S. Government Printing

Office, Oct. 1974.

15National Center for Health Statistics: Decayed,

missing, and fried teeth among children. Vital and

Health Statistics. Series 1l-No. 106. DHEW Pub. No,

(HSM) 72-1003. Health Services and Mental Health

Administration. Washington. U.S. Government Printing

Office, Aug. 1971.

16National Center for Health Statistics: Decayed,

missing, and filled teeth in adults. Vital and Health

Statistics. PHS Pub. No. 1000-Series 1l-No. 23. Public

Health Service. Washington. U.S. Government Printing

Office, Feb. 1967.

17The American Association of Orthodontists: Study

of the availability of orthodontists’ services. Am. J.

Orthod. 68(3):326-338, Sept. 1975.

18The American Association of Orthodontists: Personal communication.

1‘The American Association of Orthodontists: Personal communication,

2°National Center for Health Statistics: Vital Statistics of the United States, 1971, Vol. I, Natality. DHEW

Pub. No. (HRA) 75-1113. Health Resources Administration. Washington. U.S. Government Printing Office,

1975.

21 National Center for Health Statistics: Births, marriages, divorces, and deaths for 1975. Monthly Vital

Statistics Report, Vol. 24, No. 12. (HIL4) 76-1120.

Health Resources Administration. Rockville, Md., Mar.

4, 1976.

22 Nation~ Center for Health Statistics: Sample

design and estimation procedures for a national health

examination survey of children. Vital and Health Statistics. Series 2-No. 43. DHEW Pub. No. (HSM) 72-1005.

Health Services and Mental Health Administration.

Washington. U.S. Government Printing Office, Aug.

1971.

18
LIST OF DETAILED TABLES

Page

Table 1. Number and percant distribution of youths aged 12-17 by specified vertical overbite measurements, according to race

and sax, with standard errors of tha astimatas: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . 21

2. Numbar and percent distribution of youths aged 12-17 by specified openbite measurements, according to rata and sex,

with standard arrors of the astimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

3. Number and percent distribution of youths aged 12-17 by specified upper anterior overjet measurements, according to

race and sex, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . 23

4. Number and percant distribution of youths aged 12-17 by specified lower anterior overjet measuraments, according to

race and sax, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . 24

5, Number and parcant distribution of youths ages 12-17 by specified number of upper posterior teeth in buccal crossbite

relation, according to race and sex, with standard errors of the astimates: United States, 1966-70 . . . . . . . . . . . ’25

6. Number and parcent distribution of youths aged 12-17 by specified number of upper posterior teeth in lingual

crossbite relation, according to race and sex, with standard errors of the estimates: United States, 1966-70 . . . . . . 26

7. Number and percent distribution of youths aged 12-17 by specified tooth displacement scores, according to race and

sex, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

8. Number and parcant distribution of youths aged 12-17 by specified buccal segment ralation, according to race and sex,

with standard errors of the estimates: Unitad States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

9, Number and percent distribution of youths aged 12-17 by specified Treatmant Priority index (TPI ), according to race

and sex, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . 29

10. Number and percent distribution of youths agad 12-17 by specified Treatment Priority Index (TPI), according to age

and sax, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . 30

11, Number and percent distribution of youths aged 12-17 by specified casa severity, according to race and sex, with

standard arrors of theestimatas: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

12, Number and parcant distribution of youths aged 12-17 by specified Treatment Priority Index (TPI), according to type

of malocclusion syndrome, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . 33

13. Average Traatmant Priority Index (TPI) par youth, by race, sex, and age, with standard errors of the astimates: United

States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

14. Differences between actual and expectad average Treatment Priority Index (TPI) per youth for youths aged 12-17, by

sex, race, and annual family income, with standard errors of the astimates: United States, 1966-70 . . . . . . . . . . . 35

16. Differences between actual and axpected average Treatment Priority Indax (TPI ) per youth for youths aged 12-17, by

sex, race, and education of the head of household, with standard arrors of the astimates: United States, 1966-70 . . . 36

16. Differences between actual and expected average Treatment Priority Index (TPI ) par youth for youths aged 12-17, by

sex, race, and geographic region, with standard errors of the astimates: United States, 1966-70 . . . . . . . . . . . . . 37

17. Number and percent distribution of youths aged 12-17 by whethar or not it was reported that their teeth have bean

straightened, according to sex and age, with standard errors of tha estimates: United States, 1966-70 . . . . . . . . . 38

18. Number and percent distribution of youths agad 12-17 whose teeth hava not been straightenad by whather or not

parents thought the youths’ teeth need to be straightened, according to race, sex, and age: United States, 1966-70 39

19
Page

Table 19. Number and percent distribution of youths aged 12-17 whose teeth have not been straightened by whether or not

parents thought the youths’ teeth need to be straightened, according to rece and annual family income, with standard

errors of theestimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

20. Number of youths aged 12-17 whose teeth have not been straightened and the average Treatment Priority Index (TPI)

per youth, by race, sex, and whether or not parents thought the youths’ teeth need to be straightened, with standard

errors of theestimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

21. Number of youths aged 12-17 whose teeth have not been straightened and the average Treatment Priority Index (TPI)

per youth, by race, sex, and whether or not youths have been told by dentists that their teeth need to be

straightened, with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . 45

22. Number of youths aged 12-17 and average Treatment Priority Index (TPI) per youth, by race, sex, and whather or

not youths’ teeth have been streightened, with standard errors of the estimates: United States, 1966-70 . . . . . . . . 46

23. Number and percent distribution of youths aged 12-17 whose teeth have not been straightened, by whether or not they

thought their own teeth need to be straightened, according to sex and age, with standard errors of the estimates:

United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

24. Number of youths per 1,000 youths aged 12-17 whose teeth have been straightened, by sex and annual family income,

with standard errors of the estimates: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

20
Table 1. Number and percent distribution of youths aged 12-17 by specified vertical overbite measurements, according to race and

sex, with standard errors of the estimates: Unitad States, 1966-70

Vertical overbite in mm.

Estimated number of

youths in thousands . . . . . .

All measurements . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 .....................

1 .. . . .. .. . . . .. .. .. . .. .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 ,, .,... . . . . . . . . . . . . . .

5 ,. .,... . . . . . . . . . . . . . .

6mm. or more . . . . . . . . . . . . . .

Negative

o . . . . .

1 . . . . .

2 . . . . .

3 . . . . .

4 . . . . .

5 . . . . .

6 or more

. . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

,, ..,.. . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

+Fi Total 1 White Black

Both

Male Female

Both

Male Famale

Both

Male Female

sexes sexes sexas

22,144 11,175 10$69 19,063 9,648 9,415 2,972 1,467 1,505

Percent distribution

100.0

5.2

0.2

10.8

14.5

20.4

21.6

17.0

10.3

0.35

0.08

0.60

0.59

0.56

0.64

0.71

0.65

100.0

5.0

0.2

9.5

13.6

20.1

21.1

18.3

12.2

0.40

0.11

0.69

0.72

0.63

0.77

0.63

0.73

100.0

5.5

0.2

12.1

15.4

20.8

22.0

15.6

8.4

0.51

0.08

0.76

0.78

0.69

1.06

1.01

0.71

1Includes data for “other racas;’ which are not shown separately.

100.0

3.5

0.2

9.5

13.4

20.2

22.9

18.6

11.7T

100.0 100.0

3.5 3.5

0.2 0.2

8.1 10.9

12.4 14.4

19.8 20.7

22.2 23.5

20.0 17.2

13.8 9.6

Standard errors

0.23

0.07

0.62

0.64

0.63

0.63

0.83

0.77

0.34

0.10

0.68

0.79

0.67

0.78

0.77

0.86

0.42

0.05

0.87

0.82

0.79

1.15

1.21

0.83

t

100.0 100.0

16.3 14.5

0.5 0.5

18.7 18.3

22.0 21.8

21.2 21.9

13.2 13.6

6.7 7.2

1.4 2.2

2.15

0.35

1.56

1.04

0.97

1.83

1.13

0.34

2.14

0.39

1.70

1.81

1.88

2.65

1.76

0.53

100.0

18.0

0.6

19.1

22.1

20.5

12.8

6.2

0.7

2.68

0.44

2.21

1.94

1.23

2.13

1.16

0.38

NOTE: This table doas not include an estimated 149,000 youths with a lower overjet and a lower overbite.

21
Table 2. Number and percant distribution of youths aged 12-17 by specified openbite measurements, according to race and sex, with

standard errors of the estimates: United States, 1966-70

C)Denbite in mm.

Estimated number of

youths in thousands . . . . . ,

All measurements . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . .

6 or more . . . . . . . . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . .

6 ormore . . . . . . . . . . . . . . . .

Totell

-

Both

Male Female

sexes

22,144 11,175 10,969

100.0

94.8

1,8

1.1

1.2

0.5

0.2

0.2

0.2

0.35

0.19

0.11

0.14

0.11

0.04

0.06

0.05

100.0

95.0

1.7

1.1

1.2

0.4

0.2

0.2

0.2

0.40

0.26

0.17

0.18

0.12

0.04

0.09

0.07

100.0

94.5

1.9

1.1

1.2

0.6

0.3

0.2

0.2

0.51

0.23

0.17

0.20

0.16

0.09

0.06

0.08

W bite

TFBoth

Male Female

sexes

19,063 9,648 9,415

Percent distribution

100.0

96.5

1.4

0.9

0.7

0.2

0.1

0.1

0.1T

100.0 100.0

96.5 96.5

1.3 1.4

1.1 0.8

0.7 0.8

0.2 0.3

0.0 0.1

0.1 0.1

0.1 0.0

Standard erro)

1

0.23 0.34

0.19 0.26

0.12 0.19

0.09 0.12

0.07 0.09

0.03 0.02

0.05 0.05

0.03 0.05

0.42

0.29

0.15

0.15

0.10

0.05

0.05

0.03

8oth

sexes

2,972

100.0

83.8

3.9

2.2

4.4

2.3

1.2

1.1

1.1

2.15

0.92

0.41

0.86

0.77

0.34

0.35

0.29

Black

F

Male Female

1,467 1,505

100.0

85.5

3.4

1.4

4.7

1.9

1,2

1.2

0.7

2.14

1.00

0.49

1.17

0.76

0.31

0.55

0.36

100.0

82.0

4.3

3,0

4.2

2.6

1.3

1.0

1.6

2.68

0.98

0.71

0.94

1.00

0.65

0.35

0.58

1Includes data for “other races,” which are not shown separately.

NOTE: This table does not include an estimated 149,000 youths with a lower overjet and a lowar overbite.

22
Table 3. Number and percent distribution of youths aged 12-17 by specified upper anterior overjet measurements, according to race

and sex, with standard errors of the estimates: United States, 1966-70

Upper anterior

overjet in mm.

Estimated number of

youths in thousands . . . . . .

All measurements . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 ... ,.. . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . .

10ormore . . . .. m....... . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . .. . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . ..!... . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . .

10 ormore . . . . . . . . . . . . . . . .

Total ‘

II W bite I Black

M

Both

Male Female

Both

Male Female

Both

Male Female

sexes sexes sexes

22,293 11,267 11,026 19,183 9,727 9,456 2,996 1,479

100.0

2.5

0.1

3.9

17.6

28.6

20.1

12.3

6.9

3.5

1.8

1.1

1.6

0.18

0.04

0.31

0.67

0.54

0.50

0.37

0.25

0.22

0.15

0.12

0.10

100.0 I 100.0

2.7 2.3

0.1 0.1

3.4 4.5

16.0 19.3

27.7 29.5

20.6 19.6

13.4 11.1

7.4 6.3

3.7 3.3

1.9 1.8

1.1 1.0

2.0 1.2

0.28

0.06

0.26

0.61

0.71

0.59

0.59

0.34

0.26

0.18

0.19

0.18

0.23

0.05

0.61

0.94

0.55

0.77

0.54

0.45

0.35

0.24

0.18

0.15

Percent distribution

II

100.0 100.0

2.1 2.3

0.1 0.1

3.6 3.0

17.5 15.8

28.9 28.1

20.0 20.1

12.5 13.7

6.9 7.5

3.7 4.1

1.9 2.1

1.1 1.1

1.7 2.1

Standard errors

1

0.17 0.25

0.03 0.04

0.31 0.29

0.73 0.73

0.57 0.75

0.49 0.55

0.38 0.63

0.27 0.37

0.26 0.30

0.15 0.20

0.12 0.19

0.11 0.23

100.0

1.8

0.1

4.3

19.2

29.8

19.8

11.2

6.2

3.4

1.8

1.1

1.3

0.31

0.05

0.66

1.04

0.59

0.79

0.57

0.51

0.39

0.25

0.20

0.17

100.0

4.8

0.3

5.9

18.3

26.2

20.8

11.1

7.1

2.2

1.2

0.9

1.2

1.09

0.22

0.91

0.99

1.34

1.47

0.89

1.34

0.43

0.30

0.37

0.27

100.0

4.7

0.4

6.0

16.8

25.5

23.3

11.5

7.0

1.6

0.8

1.1

1.3

1.39

0.42

0.92

1.59

1.63

1.70

1.22

1.42

0.68

0.37

0.64

0.57

1,517

100.0

5.0

0.2

5.8

19.8

7.0

18.2

10.8

7.2

2.9

1.5

0.6

1.0

1.03

0.17

1.22

1.42

2.20

2.30

1.36

1.46

0.79

0.50

0.38

0.23

I Includesdata for “other races:’ which are not shown separately.

NOTE: This table includes an estimated 149,000 youths with a lower overiet and a lower overbite. Lower overbite was not measured

(appendix l).

–.

23
Table 4. Number and percent distribution of youths aged 12-17 by specifiad lower anterior overjet measurements, according to race

and sex, with standard errors of the estimates: United States, 1966-70

Lower anterior

overjet in mm.

Estimated number of

youths in thousands . . . . . .

All measurements . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 or more . . . . . . . . . . . . . . . .

Negative . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 or more . . . . . . . . . . . . . . . .

Total 1 II W bite I Black

Percent distribution

100.0

97.5

1.6

0.3

0.3

0.3

100.0

97.3

1.6

0.3

0.4

0.4

1

0.18 0.28

0.18 0.23

0.05 0.07

0.07 0.13

0.04 0.05

100.0

97.7

1.7

0.3

0.2

0.1

100.0

97.9

1.3

0.2

0.3

0.3

1 Includes data for ‘“other races,” which are not shown sePamtelY.

Standard errors

~

NOTE: This table includes an estimated 149,000 youths with a lower overjet and a lower overbite. Lower overbite was not measured

(appendix i).

24
Table 5, Number and percent distribution of youths aged 12-17 by specified number of upper posterior teeth in buccal crossbite

relation, according to race and sex, with standard errors of the estimates: United States, 1966-70

Number of upper

posterior teeth in

buccal crossbite

Estimated number of

youths in thousands . . . . . .

All measurements , , , , . . , . ,

0 .....................

1 . . . . . . . . .. . . . . . .. . . . .

2 ,. .,... . . . . . . . . . . . . . .

3 ,., . . . . . . . . . . . . . . . . . .

4 ,m . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7ormore . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 ... ,,. . . . .. . . .. .. . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . ... .,,,

5 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7ormore m . . . . . . . . . . . . . . .

Total 1

II W bite I

Black

Percent distribution

100.0

94.9

3.6

1.2

0.2

0.1

0.0

0.29

0.30

0.14

0.05

0.04

0.01

100.0

93.7

4.1

1.7

0.3

0.2

0.0

0.0

0.51

0.45

0.29

0.07

0.09

0.02

0.01

100.0

86.2

3.0

0.6

0.2

0.0

0.31

0.29

0.11

0.08

0.03

100,0

94.7

3.7

1.2

0.2

0.2

0.0

0.0

100.0

93.4

4.2

1.8

0.3

0.2

0.0

0.0

Standard errors

0.33

0.32

0.17

0.06

0.05

0.01

0.01

0.55

0.45

0.33

0.08

0.09

0.02

0.02

100.0

96.1

3.1

0.6

0.2

0.0

0.38

0.34

0.13

0.10

0.04

100.0

96.1

2.9

0.8

0.1

0.1

0.66

0.55

0.24

0.10

0.09

100.0 I 100.0

95.1

3.1

1.4

0.2

0.2

1.06

0.78

0.50

0.22

0.19

97.0

2.8

0.2

0.44

0.51

0.16

I Includes data for “other races,” which are not shown separately.

25
Table 6. Number and percent distribution of youths aged 12-17 by specified number of upper posterior teeth in lingual crossbite

relation, according to race and sex, with standard errors of the estimatas: United States, 1966-70

Number of upper

posterior teeth in

lingual crossbite

Estimated number of

youths in thousands . . . . . .

All measurements

o ............

1 . . . . . . .. . . . .

2 . . . . . . . . . . . .

3 . . . . . . . . . . . .

4 . . . . . . . . . . . .

5 . . . . . . . . . . . .

6 . . . . . . . . . . . .

7or more . . . . . . .

. . . . . . . . .

. . . . . . . . .

. . . . . . . . .

. . . . . . . . .

. . . . . . . . .

. . . . . . . ,.

. . . . . . . . .

. . . . . . . . .

. . . . . . . . .

0 . . . . . . . . . . . . . . . . . . .m.

1 . . . . .. .. . . . . . .. . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

6 ... ,.. . . . . . . . . . . . . . . .

7 or more . . . . . . . . . . . . . . . .

Both

sexes

22,284

100.0

B8.O

5.8

3.2

1.5

1.0

0.2

0.2

0.1

0.57

0.29

0.23

0.15

0.16

0.07

0.06

0.03

Total’

Male

11,264

100.0

89.1

6.1

2.5

1.1

0.8

0.2

0.2

0.0

0.67

0.50

0,25

0.17

0.18

0.08

0.09

0.02

Female

11,020

100.0

86.8

5.7

4.0

1.8

1.3

0.2

0.1

0.1

0.69

0.32

0.38

0.29

0.21

0.09

0.06

0.06

+FF+ White

Both

Male Female Both

sexes sexes

19,180 9,727 9,453 2,991

Percent distribution

100.0

88.3

5.8

3.1

1.4

1.0

0.2

0.2

0.0

100.0

~

89.3

6.0

2.4

1.1

0.7

0.3

0.2

0.0

Standard errors

0.59

0.30

0.26

0.17

0.17

0.08

0.06

0.03

0.71

0.48

0.29

0.22

0.18

0.10

0.10

0.02

100.0

87.4

5.5

3.7

1.8

1.2

0.2

0.1

0.1

0.80

0.39

0.41

0.33

0.25

0.10

0.06

0.05

100.0

85.3

6.7

4.4

1.7

1.5

0.1

0.2

0.1

1.18

0.75

0.51

0.39

0.34

0.09

0.14

0.14

Black

F

Male Female

1,476 1,514

100.0

87.7

6.6

3.2

1,1

1,2

0,2

1.82

1.65

0.75

0.32

0.43

0.17

100.0

83.0

6.7

5.6

2.3

1.7

0.2

0.2

0.3

1.67

1.21

0.68

0.57

0.52

0.18

0,22

0.28

1 Includes data for “other races” which are not shown separately.

26
Table 7, Number and percent distribution of youths aged 12-17 by specified tooth displacement scores, according to race and sex,

,with standard errors of the estimates: United States, 1966-70

Tooth displacement

scores

Estimated number of

youths in thousands . . . . . .

All measurements . . . . . . . . .

0 .....................

1 ., .,.,. . . .. . . . . .. . . .

2 ,. .,.... . . . . . . . . . . . . .

3 ,., ..., ... ,.. . . . . . . . .

4 ., .,.,., . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . .

6 ... .,.. . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 .,, ..., . . . . . . . . . . . . . .

9 ,, .,,,,, . ...,.., ... .,

10 . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . .

120rmore . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 ,., .,,. . . . . . . . . .. . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 . ...,.. . . . . . . . .m. m...

4 ,, . . . . . . . . . . . . . . . . . . .

5 ... ,.. . . . . . . . . . . . . . . .

6 ... ,.. . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 ., ..,... . . . . . . . . . . . . .

9

lo”::::::::::::::::::::

11 . . . . . . . . . . . . . . . . . . . .

120rmore . . . . . . . . . . . . . . . .

Both

sexes

22,670

100.0

13.4

5.2

11.7

7.2

11.8

8.5

9.7

6.3

6.7

5,1

4.2

2.8

7.4

Total 1

Male Female

11,470 j 11,200

100.0

13.6

5.2

12.0

7.1

11.9

9.0

9.7

6.4

6,5

4.5

4.3

2.7

7.1

i

1.32 1.44

0.36 0.51

0.51 0.65

0.42 0.44

0.49 0.88

0.40 0.53

0.50 0.63

0.37 0.46

0.32 0.44

0.43 0.33

0.30 0.35

0.24 0.32

0.65 0.53

100.0

13.2

5.2

11.3

7.3

11.7

8.1

9.7

6.2

6.9

5.7

4.0

3.0

7.7

1.39

0.46

0.53

0.60

0.54

0.55

0.53

0.50

0.56

0.69

0.40

0.33

0.94

+FF White

Both

Male Female

8oth

sexes sexes

19,534 9,914 9,620 3,020

Percent distribution

100.0

13.0

5.1

11.1

7.1

11.7

8.6

9.8

6.5

6.8

5.3

4.2

2.9

7.8

100.0

13.2

5.1

11.5

7.1

12.0

8.9

9.9

6.5

6.4

4.8

4.3

2.9

7.4

Standard errors

1

1.42 1.65

0.40 0.58

0.54 0.70

0.44 0.46

0.51 0.99

0.39 0.49

0.57 0.70

0.38 0.48

0.39 0.50

0.48 0.38

0.32 0.38

0.23 0.36

0.75 0.57

100.0

12.8

5.1

10.8

7.1

11.3

8.4

9.8

6.5

7.2

5.8

4.0

3.0

8.2

1.52

0.51

0.60

0.67

0.51

0.59

0.61

0.53

0.61

0.76

0.42

0.28

1.10

100.0

16.0

5.8

15.2

8.0

12.5

8.0

8.7

4.9

6.1

3.2

4.2

2.2

5.1

2.17

0.81

0.95

1.11

1.10

1.43

0.89

1.10

0.95

0.40

0.67

0.45

0.67

Black

--tMale Female

1,493 j 1,527

I00.0

-

16.3

5.8

15.5

7.2

11.0

9.8

8.5

5.5

6.9

2.1

3.7

2.1

5.5

3.00

0.88

1.83

1.51

1.64

2.33

1.09

1.07

1.80

0.61

1.05

0.51

0.83

100.0

15.8

5.6

14.9

8.7

13.9

6.3

8.9

4.4

5.2

4.4

4.7

2.4

4.8

2.23

1.05

0.87

1.00

1.72

1.15

1.50

1.27

1.28

1.01

0.80

0.78

0.91

1 Includes data for “other races,” which are not shown separately.

27
Table 8. Number and percent distribution of youths aged 12-17 by specified buccal segment relation, according to rata and sex, with

standard errors of the estimates: United States, 1966-70

8uccal segment

relation

Estimated number of

youths in thousands . . . . . .

All relations . . . . . . . . . . . .

Neutroclusion2 . . . . . . . . . . . . . .

Mesioclusion

Unilateral . . . . . . . . . . . . . . .

Bilateral . . . . . . . . . . . . . . .

Distoclusion

Unilateral . . . . . . . . . . . . . . .

Bilateral . . . . . . . . . . . . . . .

Mixed . . . . . . . . . . . . . . . . . .

Neutroclusion2 . . . . . . . . . . . . . .

Mesioclusion

Unilateral . . . . . . . . . . . . . . .

Bilateral . . . . . . . . . . . . . . .

Distoclusion

Unilateral . . . . . . . . . . . . . . .

Bilateral . . . . . . . . . . . . . . .

Mixed . . . . . . . . . . . . . . . . . .

Total 1

II White I

Black

Percent distribution

100.0

53.5

7,5

6.3

17.0

14.5

1.2

0.94

0.58

0.52

0.66

0.73

0.15

100.0

53.4

7.5

6.4

16.8

14.6

1.3

1.33

0.52

0.55

0.90

0.58

0.24

100.0

53.8

7.6

6.1

17.1

14.4

1.0

0.88

0.82

0.63

0.63

1.11

0.21

100.0

52.2

7.0

6.0

17.8

15.8

1.2

I 00.0

52.2

6.8

6.2

17.3

16.2

1.3

Standard errors

0.94

0.67

0.58

0.67

0.84

0.17

1.28

0.61

0.63

0.88

0.62

0.28

100.0

52.4

7.2

5.8

18.2

15.4

1.0

0.88

0.93

0.68

0.70

1.25

0.25

100.0

62.4

10.9

7.7

12.0

6.0

1.0

2.67

0.72

1.12

1.80

0.74

0.13

100.0

60.7

12.3

7.9

13.6

4.1

1.4

4.25

0.97

1.47

2.73

1.10

0.30

100.0

64.2

9.5

7.5

10.5

7.7

0.6

2.14

1.07

1.22

1.25

1.20

0.26

1 Includes data for ‘#Other races,” which are tIOt shown separately.

20nly youths with both right and left buccal segments scored normal are classified as havin9 neutroclusion.

28
Table9, Number andpercent distribution of youths aged 12-17 by specified Treatment Priority Index (TPl), according to race and

sex, with standard errors of the estimates: United States, 1966-70

Treatment Priority

Index

Estimated number of

youths in thousands . . . . . .

AIITPI . . . . . . . . . . . . . .

o . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . .. . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 ,,, ,,, ,,. . . . . . . . . . . . .

4 ,. . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . .

9 ., ..,.. . . . . . . . . . . . . . .

lo . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . .

12 . . . . . . . . . . . . . . . . . . . .

130rmore . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . .. .. . . . . . .

2 . . . . . . . . . . . . . . . . . . . . .

3 ,,, ..,,. . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . .

8 ,....., . . . . . . . . . . . . . .

9 .,,.,., . . . . . . . . . . . . . .

lo . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . .

12 . . . . . . . . . . . . . . . . . . . .

130rmore . . . . . . . . . . . . . . . .

Total 1

II White I

Black

Percent distribution

100.0

11.0

9.5

13.2

12.2

8.4

9.0

7.7

3.9

5.2

3.9

5.3

2.2

2.4

6.1

0.64

0.63

0.45

0.49

0.37

0.42

0.37

0.24

0.28

0.25

0.50

0.22

0.17

0.58

100.0

10.9

8.8

13.4

11,7

8.8

8.9

7.9

4.1

4.9

3.9

5.4

2.5

2.6

6.2

0.72

0.69

0.44

0.62

0.45

0.63

0.45

0.28

0.38

0.44

0.59

0.35

0.31

0.64

100.0

11.2

10.2

12.9

12.6

8.1

9.2

7.4

3.7

5.6

3.9

5.3

1.9

2.2

5.9

0.74

0.76

0.74

0.83

0.52

0.48

0.50

0.36

0.53

0.33

0.62

0.31

0.29

0.59

100.0

10.5

9.5

12.8

12.3

8.6

9.4

7.7

3.9

5.2

3.9

5.6

2.4

2.3

5.9

100.0

10.2

8.7

13.1

11.7

8.9

9.0

8.1

4.0

4.9

3.8

6.0

2.7

2.6

6.3

Standard errors

0.69

0.72

0.43

0.54

0.41

0.48

0.40

0.27

0.32

0.29

0.52

0.26

0.17

0.64

0.77

0.82

0.58

0.64

0.50

0.72

0.49

0.31

0.42

~ 0.45

0.65

0.36

0.29

0.73

100.0

10.7

10.2

12.5

12.9

8.4

9.8

7.3

3.8

5.4

4.0

5.4

2.0

2.1

6.5

0.84

0.83

0.78

0.93

0.54

0.53

0.57

0.39

0.63

0.45

0.65

0.36

0.29

0.64

100.0

14.7

9.6

15.7

11.6

7.2

6.8

7.0

3.5

5.2

3.5

3.5

1.6

2.8

7.3

1.21

0.98

0.99

0.73

0.84

0.82

0.55

0.77

0.59

0.52

0.63

0.42

0.62

0.70

100.0

15.0

8.9

15!5

12.0

8.6

8.4

6.3

4.0

5.4

4.2

1.9

1.5

2.3

6.0

2.06

1.11

1.56

1.40

1.01

1.42

0.64

0.80

0.83

0.71

0.52

0.69

0.86

0.83

100.0

14.3

10.3

16.8

11.2

5.9

5.2

7.7

3.1

5.0

2.8

5.1

1.6

3.4

8.6

0.85

1.38

1.73

1.75

1.04

0.73

0.92

0.97

0.97

0.51

1.07

0.51

0,83

0.96

1 Includes data for “other races,” which are not shown separately.

29
Table IO. Number and percent distribution of youths aged 12-17 by specified Treatment Priority Index (TPl), according to age and

sex, with standard errors of the estimates: United States, 1966-70

Treatment Priority

Index

Estimated number of

youths in thousands . . . . . .

AIITPI . . . . . . . . . . . . . . .

o . . . . . . . . . . . . . . . . . . . . . .

1 . . .. .. . . .. . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . . .

lo . . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . . .

12 . . . . . . . . . . . . . . . . . . . . .

130rmore . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . . .

lo . . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . . .

12 . . . . . . . . . . . . . . . . . . . . .

130rmore . . . . . . . . . . . . . . . .

12-17 years 12 years I 13 years

T

Both

Male

sexes

22,276 11,260

100.0

11.0

9.5

13.2

12.2

8.4

9.0

7.7

3.9

5.2

3.9

5.3

2.2

2.4

6.1

0.64

0.63

0.45

0.49

0.37

0.42

0.37

0.24

0.28

0.25

0.50

0.22

0.17

0,58

100.0

10.8

8.8

13.4

11.7

8.8

8.9

7.9

4.0

4.9

3.8

5.4

2.5

2.6

6.2

0.72

0.69

0.44

0.62

0.45

0.63

0.45

0.28

0.38

0.44

0.59

0.35

0.31

0.64

4

Female

Both

Male Female

Both

sexes

Male Female

sexes

11,016 3928 2,002 1,926 3,885 1,969 1,916

100.0

11.2

10.2

12.9

12.6

8.1

9.2

7.4

3.7

5.4

3.9

5.3

1.9

2.2

5.9

0.74

0.76

0.74

0.83

0.52

0.48

0.50

0.36

0.53

0.33

0.62

0.31

0.29

0.59

Percent distribution

100.0

10.6

7.1

13.0

12.3

7.4

10.4

9.3

4.3

4.2

4.1

6.1

2.1

2.4

6.4

100.0

~

11.5

8.2

14.2

11.0

8.7

10.2

9.3

4.3

3.0

4.2

5.3

2.6

3.2

4.8

100.0

9.6

6.0

11.9

13.7

6.6

10.7

9.4

4.4

5.5

4.0

6.9

1.6

1.6

8.0

Standard errors

1.17

0.81

0.90

1.21

0.99

0.81

1.15

0.55

0.67

0.82

0.74

0.38

0.44

1.14

1.40

1.08

1.31

1.34

1.02

1.12

1.42

0.63

0.77

0.91

1.00

0.64

0.58

1.21

1.56

1.18

1.18

1.86

1.43

1.32

1.52

0.93

1.06

1.32

1.11

0.50

0.59

1.24

100.0

12.1

10.0

12.2

12.3

9.5

8.5

6.4

4.1

5.2

3.7

4.4

2.1

1.7

7.8

1.10

1.05

0.95

0.92

0.62

1.08

0.90

0.53

0.65

0.49

0.65

0.29

0.35

1.16

100.0

11.0

10.1

12.7

12.2

9.6

8.8

6.5

4.8

4.9

4.4

3,8

2.1

0.8

8.1

1.39

1.70

1.08

0.86

0.84

1.43

0.83

0.89

0.76

0.79

0.94

0.62

0.44

1.60

100.0

13.2

9.9

11.7

12.4

9.4

8.2

6.4

3.3

5.6

2.9

5,0

2.0

2.6

7.5

1.81

1.27

1.55

1.72

1.17

1.52

1,36

0.61

1.22

0.47

0.80

0.41

0.75

1.23

30
Table IO, Number andpercent distribution of youths aged 12-17 by specified Treatment Priority Index

14 years

TFBoth Male Female

sexes

3,772 1,897 1,874

100,0

10.4

9.9

12,7

13.3

7.8

10.0

7,4

3.4

5.0

4,2

5,9

1,6

2.1

6.2

0.78

1.11

1.03

1.45

0.65

1,15

0.65

0.56

0.80

0.79

0.94

0.35

0.36

0.77

100.0

11.3

7.7

13.4

12,5

8.6

10.7

7.0

3.6

4.4

4.4

5.1

2.2

2.1

7.0

1.16

1.34

1,70

1.59

1.06

1.25

1.10

0.65

1.05

1.13

1.45

0.64

0.55

1.17

100.0

9.5

12.2

11.9

14,1

7.1

9.3

7.7

3.3

5.6

4.1

6.7

1.0

2.1

!5.4

1.00

1.73

1.41

2.53

0.99

1.81

1.02

0.71

1.04

1.14

1.38

0,33

0.59

0.84

sex, with standard errors of the estimates: United States, 1966-70—Con.

(TP I), according to age and

15 years I

16years I

17 years

T

Both Male

sexes

3,679 1,869

T

100.0 100.0

10.0 10.0

10.0 9.4

12.8 11.5

10.6 11.2

9.7 9.1

8.0 7.2

8.8 9.1

3.9 4.1

5.6 6.2

4.0 3.3

5.4 4.4

2.7 3.7

3.6 4.2

5.0 6.6

1.46

1.41

1.04

1.30

1.08

0.96

0.64

0.69

1.00

0.37

0.98

0.74

0.45

0.91

2.03

1.69

1.23

1.87

1.19

1.27

1.32

0.83

0.94

0.68

0.96

1.09

0.92

1.14

Female Both

Male Female Both Mele Female

sexes sexes

1,808 3,583 1,811 1,772 3,427 1,709

Percent distribution

100.0

9.9

10.7

14.1

10.1

10.4

8.8

8.5

3.7

4.8

4.7

6.4

1.7

2.9

3.3T

100.0 100.0

12.4 11.7

9.1 7.5

13.3 13.3

13.0 12.7

9.4 10.4

9.2 9.4

6.7 7.4

2.0 3.0

5.1 5.8

3.2 2.5

5.4 6.3

3.0 2.1

2.4 3.1

4.8 4.6

Standard errors

1.65

1.69

1.79

1.68

1.52

1.21

0.95

0.82

1.46

0.68

1.62

0.60

0.58

0.82

1.25 1.43

0.77 0.92

1.15 1.62

0.76 1.11

1.02 1.51

0.87 0.99

0.94 1.40

0.52 0.66

0.70 1.25

0.48 0.66

0.89 1.12

0.50 0.44

0.62 0.99

0.76 1.09

100.0

13.1

10.7

13.4

13.2

8.3

9.0

6.0

3.0

4.3

3.9

4.4

3.8

1.7

5.1

2.14

1.18

1.37

1.04

1.08

1.44

1.34

0.72

1.18

0.62

1.02

0.94

0.59

0.82

100.0

10.7

10.9

15.4

11.4

6.8

8.0

7.2

4.4

6.2

4.0

4.8

2.0

2.2

6.0

100.0

9.4

9.8

15.7

10.9

6.9

6.9

8.1

4.5

5.4

4.3

7.7

2.3

1.9

6.1

1.06 1.34

1.25 1.45

1.00 1.52

0.70 1.22

0.88 1.18

0.97 1.04

1.01 1.50

0.59 0.77

0.73 1.15

0.57 0.81

0.67 1.37

0.55 0.97

0.45 0.66

0.56 1.09

1,718

100.0

12.0

11.9

15.1

12.0

6.7

9.0

6.2

4.4

6.9

3.6

2.0

1.6

2.5

6.0

1.46

2.13

1.43

1.42

1.22

1.57

1.05

1.03

1.03

0.96

0.49

0.60

0.71

0.70

31
Tablell. Numbar and parcent distribution of youths aged 12-17 by specified case severity, according toraceand sex, with standard

errors of the estimates: United States, 1966-70

Specified case

severity

Estimated number of

youths in thousands . . . . . .

All cases . . . . . . . . . . . . . .

O (Normal occlusion) . . . . . . . . . . .

l-3 (Minor malocclusion) . . . . . . . .

4-6 (Definite malocclusion) . . . . . . .

7-9 (Severe malocclusion) . . . . . . . .

10 or more (Very severe

malocclusion ) . . . . . . . . . . . . .

0 (Normal occlusion) . . . . . . . . . . .

1-3 (Minor malocclusion) . . . . . . . .

4-6 (Definite malocclusion) . . . . . . .

7-9 (Savere malocclusion) . , . . . . . .

10 or more (Very severe

malocclusion ) . . . . . . . . . . . . .

Total 1 II White I

Black

TFl Both

Male Female

Both

Male Female

Both

sexes sexes

Male Female

sexes

22,277 11,260 11,017 19,173 9,723 9,450 2,990 1,476

T

100.0 100.0

11.0 10.8

34.8 34.0

26.2 25.7

13.0 12.8

16.0 16.7

0.64 0.72

0.89 0.95

0.75 0.81

0.39 0.53

Percent distribution

100.0

Ilm

100.0 100.0 100.0

11.2 10.5 10.2 10.7

35.8 34.5 33.6 35.7

24.6 25.8 26.0 25.5

13.0 13.0 12.7 13.2

15.4 16.2 17.5 14.9

0.74

1.50

1.13

0.65

1.42

Standard errors

0.69

1.08

0.82

0.45

_H_uJ2— _

1.24

0.77 0.84

1.04 1.66

0.89 1.23

0.60 0.76

100.0

14.7

36.9

21.0

12.2

15.2

100.0

15.0

36.4

23,3

13.5

11.8

1,514

100.0

14.3

37.3

18.8

11,0

18.6

J__

1.21 2.06 0.85

1.37 1.68 2.13

1.15 1.83 1.23

0.81 1.16 1.06

1.15 1.50 1.95

1 Incllscfasdata for “other races,” which are not shown separately.

32
Table 12, Number and percent distribution of youths agad 12-17 by spacified Treatment Priority Index (TPI), according to type of

malocclusion syndrome, with standard arrors of the estimates: United Statas, 1966-70

Treatment Priority

Index

Estimated number of

youths in thousands . . . . . . . .

AIITPI . . . . . . . . . . . . . . . .

o . . . . . . . . . . . . . . . . . . . . . . .

1 ,, .,.... . . . . . . . . . . . . .. .

2 ., ..,.. . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . . . .

9 ,, .,... . . . . . . . . . . . . . . . .

10 ormore . . . . . . . . . . . . . . . . . .

0 ... .,.. . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . .. .. . . . . . . . .

2 ,., . . . . . . . . . . . . . . . . . . . .

3 ,. .,..! . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . . . .

8 ,., .,.. . . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . . . .

10ormore . . . . . . . . .. o.. . . . . .

Type of malocclusion syndrome

Tooth displacement Anterior

Normal

Maxillary Maxillary Over- Open- Lower Upper

expansion

Mixed’

collapse bite bite overjat overjet

12,099 2,657 4,017 1,167 860 34 1,154 285

Percent distribution

100.0

20.3

17.4

24.3

22.4

15.6

.92

0.91

0.73

0.88

0.77

22.7

18.7

9.7

13.3

11.5

24.1

1.66

1.35

0.87

1.14

1.41

2.19

21.0

14.8

4.7

11.5

6.7

41.3

1.08

1.09

0.57

1.01

0.88

1.67

100.0

7.3

11.3

3.0

8.5

12.6

57.3

100.0

7.1

20.0

16.4

19.4

7.6

29.5

Standard errors

1.71

2.51

1.03

1.62

2.04

3.22

1.72

3.08

3.36

1.53

0.95

2.46

100.0

9.1

90.9

9.97

9.97

100.0

26.7

25.5

18.4

6.1

5.1

18.2

1.83

3.24

1.89

1.12

0.93

3.75

100.0

39.8

5.8

9.6

1.2

4.2

39.4

5.81

2.32

4.57

1.24

2.78

6.60

1TWO or more TPI components of equally high weight.

33
Table 13. Average Treatment Priority Index (TPI) per youth, by race, sex, and age, with standard errors of the estimates: United

States, 1966-70

Sex and age

Bothsexes 12-17 years . . . . . . . . . . . . . . . . . . . . . . . .

12 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . .. m...... . . . . . . . . . . . . . . . . . . . . . .

14years m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Male12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12Years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..O

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..OO

17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

=lF=l=

Average TPI

5.0

5.2

5.1

5.0

5.1

4.8

4.9

5.1

5.0

5.1

5.1

5.4

4.9

5.2

4.9

5.5

5.1

4.9

4.8

4.6

4.6

5.1

5.4

5.1

4.9

5.1

4.8

5.1

5.2

5.2

5.2

5.1

5.5

4.9

5.4

4.9

5.6

5.0

4.7

4.8

4.6

4.8

4.9

4.5

4.9

5.5

5.0

5.1

4.2

4.6

4.1

4.2

4.8

5.0

5.3

4.5

5.1

4.9

5.6

6.1

4.9

5.0

3.9

Standard errors

0.14

0.23

0.16

0.18

0.24

0.18

0.15

0.14

0,23

0.19

0.19

0.30

0.19

0.19

0.16

0.27

0.23

0.23

0.28

0.22

0.20

0.16

0.26

0.16

0.19

0.27

0,20

0.14

0.15

0,27

0.18

0.21

0.31

0.23

0.20

0.18

0.30

0.27

0.25

0.30

0.26

0.19

0.13

0,26

0.30

0.37

0.33

0.35

0,55

0.22

0.36

0.54

0.60

0.63

0.49

0.62

0.21

0.30

0.42

0,73

0.63

0.60

0.71

1 Includes data for ~J~ther racas,” which are nOt shown separately.
Table 14. Differences between actual and expected average Treatment Priority Index (TPI) per youth foryouths aged 12-17, bysex, race, andannualfamilv

income, with standard errors of the estimates: United States, 1966-70

Both sexes Males Femalas IIBoth

Male Female

;exes

Race and annual

family income

*

Actual I

Ex- Difpacted ference

Actual I

Ex- 1

Difpected ference

1 1

Average TPI Average TP I Average TPI Standard errors

Allracesl . . . . . . . . . . 5.0 5.1 0.14

Lessthan$3,000 . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . .

$16,0000 rmore . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

White . . . . . . . . . . . . . .

Lessthan $3,000 . . . . . . . . . .

$3.000-$4,999 . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . .

$7,000.$9,999 . . . . . . . . . . .

$10,000.$14,999 . . . . . . . . . .

$15,0000rm0re . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

Black . . . . . . . . . . . . . .

Less than $3,000

$3,000-$4,999 . ::::::::::

$5,000-$=,999 . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . .

$16,0000rmore . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

4.9 0.14 0.16

0.21

0.32

0.20

0.30

0.30

0.20

0.35

0.18

0.27

0.37

0.26

0.31

0.31

0.19

0.29

0.21

0.31

0.41

0.51

0.83

1.25

2.96

1.72

... ... ... ... ... ...

0.1

-0.1

-0.1

0.1

0.2

-0.3

0.1

...

5.4

5.2

4.8

5.3

4.6

4.0

5.1

4.9

4.9

5.0

4.9

4.9

4.9

4.9

4.9

...

0.5

0.2

-0.1

0.4

-0.3

-0.9

0.2

...

0.19

0.22

0.17

0.22

0.23

0.22

0.25

0.16

0.33

0.23

0.26

0.22

0.22

0.35

0.44

0.15

5.3

5.1

4.9

5.2

5.0

4.4

5.2

5.1

5.0

5.0

5,0

5.0

5.0

5.0

5.0

...

0.3

0.1

-0.1

0.2

0.0

-0.6

0.2

...

0.6

0.2

-0.1

0.2

-0.2

-0.6

-0.2

...

5.2

5.0

5.0

5.2

5.3

4.8

5.2

5.2

5.7

5.2

5.1

5.2

5.3

4.8

5.0

4.6

5.1

5.1

5.1

5.1

5.1

5.1

5.1

...

0.27

0.25

0.20

0.22

0.24

0.22

0.24

0.13

0.18

0.26

0.30

0.68

0.72

1.81

1.34

0.45

0.28

0.30

0.21

0.23

0.34

0.35

0.22

0.31

0.29

0.58

0.92

0.52

3.65

1.81

5.7

5.3

4.9

5.3

4.9

4.4

4.9

4.9

5.1

5.1

5.0

3.1

5.1

5.0

5.1

...

5.2

5.2

5.2

5.2

5.2

5.2

5.2

...

0.5

0.0

-0.1

0.1

0.1

-0.4

-0.2

.. .

5.7

5.4

4.7

5.3

4.6

4.0

4.8

5.1

4.9

4.9

4.9

4.9

4.9

4.9

4.9

...

0.8

0.5

-0.2

0.4

-0.3

-0.8

-0.1

...

4.7

4.6

4.8

4.8

5.2

4.3

6.6

4.9

4.9

4.8

4.8

4.8

4.9

4.9

-0.2

-0.3

0.0

0.0

0.4

-0.6

0.7

4.5

4.3

4.7

4.6

5.0

5.0

8.3

4.7

4.6

4.6

4.6

4.6

4.6

4.7

-0.2

-0.3

0.1

0.0

0.4

0.4

1.6

4.9

5.0

4.9

5.1

5.2

3.4

6.9

5.1

5.2

5.0

5.1

4.8

5.2

5.1

-0.2

-0.2

-0.1

0.0

0.4

–1 .6

1.8

I [n~ludes data for “other races,” which are not shown Separately.

35
Table 15. Differences between actual andexpacted average Treatment Priority Index (TP1) Der VOuth forvouthsaqsd 12-17 .bvsex, race, and education of

the haad”of household, with standard erro~ of the astimates: “United Statas, 196;-70

Both sexes Male Female I I

Race and education

of head of household

Actual I

Ex- 1

Difpected ference

Actual I

Ex- 1

Difpacted ference

Actual I

Ex- 1

Difpected ference

Average TP i Average TP I Average TP I

Allracesl . . . . . . . . . . 4.9 4.8

Noneorless than 5years . . . . . .

5-7 years . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . .

9-n yeara . . . . . . . . . . . . . .

12 years . . . . . . . . . . . . . . .

13-15years . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . .

17years0rm0re . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

White . . . . . . . . . . . . . .

Naneorlessthan5 years . . . . . .

5-7years . . . . . . . . . . . . . .

8yeara . . . . . . . . . . . . . . .

9-n years . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . .

13-15years . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . .

17years0rm0re . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

Black . . . . . . . . . . . . . .

Nmseorless than 5years . . . . . .

5-7years . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . .

9-n years . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . .

13-15years . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . .

17yearsormore . . . . . . . . . .

Unknown . . . . . . . . . . . . . .

... ... 5.0 ... ... ... ... 0.14 0.13 0.16

5.3

5.2

5.0

5.2

4.9

4.6

4.6

4.3

5.6

5.0

5.0

5.0

4.9

4.9

4.9

4.9

4.9

5.0

4.9

...

0.3

0.2

0.1

0.3

0.0

–0.3

-0.3

-0.7

0.7

...

5.1

5.1

4.7

5.0

5.2

4.8

4.7

4.6

6.0

5.1

5.0

5.0

5.0

5.0

5.0

5.0

5.0

5.0

5.0

...

0.1

0.1

-0.3

0.0

0.2

-0.2

-0,3

-0.4

1.0

...

5.6

5.2

5.2

5.3

4.5

4.4

4.4

3.9

5.2

4.6

4.9

4.9

4.8

4.8

4.9

4.8

4.8

4.9

4.8

...

0.7

0.3

0.4

0.5

-0.4

-0.4

-0.4

-1.0

0.4

...

1.2

0.8

0.3

0.6

-0.4

-0.4

-0.4

-1.0

0.5

...

0.47

0.23

0.24

0.17

0.18

0.34

0.22

0.30

0.38

0.15

0.62

0.34

0.20

0.15

0.21

0.39

0.29

0.24

0.55

0.34

0.38

0.22

0.19

0.49

0,36

0.43

0.66

0.18

0.72

0.40

0.38

0.26

0.21

0.49

0.37

0.39

0.75

0.22

0,82

0.15

5.7

5.5

5.0

5.2

4.8

4.6

4.6

4.3

5.8

4.8

4.6

4.3

5.2

4.8

5.7

4.1

3,8

4,9

4.9

5.0

5.0

5.0

5.0

5.0

5.0

5.0

5.0

5.0

...

0.7

0.5

0.0

0.2

-0.2

-0.4

-0.4

-0.7

0.8

...

5.4

5.5

4.8

5.1

5.2

4.9

4.7

4.7

6.3

4.6

5.1

5.1

5.1

5.1

5.1

5.1

5.1

5.1

5.1

...

0.3

0.4

-0.3

0.0

0.1

-0.2

-0.4

-0.4

1.2

...

6.0

5.6

5.1

5.4

4.4

4.4

4.4

3.8

5.3

5.0

4.8

4.8

4.6

4.8

4.8

4.8

4.8

4.6

4.8

...

0.57

0.26

0.24

0.20

0.19

0.34

0.23

0.31

0.37

0.13

0.59

0.40

0.21

0.19

0.23

0.39

0.29

0.28

0.92

0.22

4.8

4.8

4.8

4.8

4.6

4.7

4.6

4.8

5.0

-0.2

-0.5

0.4

0.0

0.9

-0.6

-0.8

0.1

-0.1

4.4

4.3

4.1

4.5

5.6

4.1

4.5

2.7

4.7

4.5

4.5

4.5

4.6

4.6

4.6

4.5

4.6

4.8

-0.1

-0.2

-0.4

-0.1

1.0

-0.5

0.0

-1.9

-0.1

4.6

4.3

6.5

5.0

5.7

4.1

2.5

10.7

5.0

5.1

5.0

5.0

5.0

5.1

4.8

5.0

5.3

5.1

-0.5

-0.7

1.5

0.0

0.6

-0.7

-2.5

5.4

-0.1

0.37

0.28

0.54

0.25

0.42

0.90

1.13

2.25

0,82

0.58

0.43

0.38

0.42

0.47

0.96

0.25

0.47

1.67

0.33

5.65

1.34

0.36

0.73

1.11

1.68

0.90

1.21

1 Includes data for “other races,” which are not shown separately.

36
Table 16. Differences between ectual and expected average Treatment Priority index (TPI) per youth for youths aged 12-17, bysex, race, and geographic

region, with standard errors of the estimates: United States, 1966-70

Male Female IIBoth

Male Female

sexes

Both sexes

Race and region

Actual I

Ex- 1Difpacted ference E&4& Actual

Expected

Difference

I I

Average TP I Average TP I Average TP I Standard errors

5.1

4.8

5.5

5.3

4.8

5.2

Allracesl . . . . . . . . . .

Northcmt . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . .

west . . . . . . . . . . . . . . . . .

White . . . . . . . . . . . . . .

Northeast . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . .

81ack . . . . . . . . . . . . . .

Northeast . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . .

west . . . . . . . . . . . . . . . . .

IT

5.0 ... ...

4.8 5.0 -0.1

5.3 5.0 0.5

5.2 5.0 0.2

4.7 5.0 0.2

... ... 4.9 ... ... ... ...

4.8

5.1

5.2

4.6

4.9

4.9

4.9

4.9

4.9

.. .

-0.1

0.2

0.3

-0.3

...

0.19

0.46

0.16

0.47

0.16

0.21

0.44

0.27

0.46

0.15

0.18

0.49

0.13

0.52

0.18

0.19

0.52

0.13

0.53

0.21

0.41

0.41

0.35

1.49

5.1

5.1

5.1

5.1

...

-0.3

0.4

0.2

-0.3

... 5.1 / ... I ...

L

4.8 5.1 -0.3

5.3 5.1 0.2

5.5 5.1 0.4

4.7 6.1 -0.4

4.9 ... ...

4.8

5.0

5.4

4.6

5.1

4.9

4.9

4.9

4.9

...

-0.1

0.1

0.5

-0.3

...

0.18

0.50

0.18

0.49

0.13

0.19

0.49

0.30

0.49

0.22

—

0.62

0.66

0.32

0.38

4.8

5.5

5.6

4.8

4.6

5.2

5.2

5.2

5.2

...

-0.4

0.3

0.4

-0.4

...

5.3

6.0

4.6

5.2

5.1

5.1

5.1

5.0

0.2

0.9

-0.5

0.2

0.45

0.40

0.16

0.79

4.5

5.6

4.3

4.7

4.6

4.7

4.6

4.6

-0.1

0.9

-0.3

0.1

1 lncl”de~ data for ,+~ther races,” which are nOt reported sePa~tetY.

37
Table 17. Number and percent distribution of ycmths aged 12-17 bywhethercwnm itwasrepcmted that their teeth have been straighten~, a=Ordingto sex and

age, with standard errors of the estimates: United States, 1966-70

Sex and aga

Estimated number ofycwthsinthmmands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B0thsexes12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15yaars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Male12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female 12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Bothsexas12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Male12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17year5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Percent distribution

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

. . .

...

.. .

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

. ..

10.7

7.4

9.5

10.4

10.6

13.5

13.3

9.6

6.0

9.7

10.2

9.4

12.8

10.0

11.8

8.7

9.3

10.6

11.9

14.1

16.7

0,68

1.37

0.61

1.41

0.B9

1.17

1.58

0.71

1.32

1.26

1.41

0.6B

1.37

1.91

0.83

1.94

1.15

1.82

1.57

1.65

2.24

B9.2

92.5

90.5

89.4

B8.4

86.5

86.7

90.3

93.8

90.3

89.4

90.6

87.2

90.0

88.2

Standard errors

91.3

90.7

89.4

8B.1

85.9

83.3

0.69

1.41

0.61

1.42

0.89

1.17

1.66

0.72

1,43

1.26

1.41

0.86

1.37

1.91

0.83

1.94

1.15

1.82

1.57

1.65

2.24

0.1

0.1

0.0

0.2

0.0

0.0

0.0

0.1

0.2

0.0

0.4

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.03

0.12

0.00

0.15

0.0

0.0

0.0

0.06

0.24

0.00

0.31

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

38
Toble 18. Number and percent distribution of youths aged 12-17 whose teeth have not been straightened by whether or not parents thought the youths’ teeth

need to restraightened, according torace, sex, and age: United States, 1966-70 -

Race, sex, and age

Parents reported need

fortooth straightening

Estimated number ofyOuths in thousands . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Total 1

87.4 0.3

0.2

0.2

0.0

0.6

0.3

0.6

0.4

8othsexes12-17years, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

11.6

14.6

11.6

12.6

11.6

10.6

7.7

10.6

13.0

12.2

10.4

10.6

10.5

5.9

12.8

0.7

84.4

87.1

86.8

86.8

88.7

91.1

88.1

85.9

86.8

88.9

86.8

88.9

92.0

86.5

0.8

1.1

0.6

0.8

0.4

0.6

Malc12.17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9

0.2

0.2

0.0

1.1

0.2

0.9

0.2

0.9

0.8

0.7

1.4

0.4

1.2

Femele12.17vears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.6

100.0

100.0

100.0

100.0

100.0

100.0

. . .

16.4

11.1

14.8

13.1

10.7

9.6

62.8

87.3

84.7

86.7

88.5

80.0

0.1

0.2

0.0

0.0

0.4

0.4

0.7

1.4

0.5

0.2

0.4

0.0

0.16

Totalq Standard errors

Bothsexes12.17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.45 0.47 0.13

12ycars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13ycwa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14yeiws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

l(iycar s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.17

0.87

0.78

1.03

0.81

0.87

0.47

1.28

1.02

0.81

1.10

0.75

0.69

0.55

0.11

0.11

0.00

0.34

0.16

0.48

0.26

0.31

0.35

0.19

0.48

0.18

0.32

0.24

.. .

. ..

.. .

. ..

...

Male12-17ycars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .

1.64

1.48

1.18

1.69

1.18

1.13

0.67

1.75

1.23

1.48

1.32

1.38

1.19

1.90

1.54

1.23

1.64

1.16

1.14

0.68

1.64

1.48

1.48

1.25

1.30

1.32

0.17

0.16

0.00

0.67

0.17

0.86

0.05

0.15

0.17

0.00

0.00

0.26

0.37

0.43

0.35

0.22

0.92

0.25

0.61

0.12

0.38

0.60

0.28

0.16

0.27

0.00

. ..

.. .

. ..

..

...

...

Female12-17vears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .

. ..

. ..

...

. ..

. ..

. . .

1 ln~lud~~ data for “other races: which are not shown separately.

39
Table 18. Number and percent distribution of youths aged 12-17 whose teeth have not been straightened by whether or not parents thought the youths’

taeth need to be straightenad, according to race, sex, and aga: United States, 1966-70–Con.

Race, sex, and age

II Parents reported need

for tooth straightening

Estimated number ofyouths in thousands . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

W bite

Bothsexes12.17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Percent distribution

100.0 12.0 86.9 0.3 0.8

0.8

1.2

0.4

1.0

0.3

0.7

0.9

0.9

0.9

0.4

1.7

0.2

1.4

0.6

100.0

100.0

100.0

100.0

100.0

100.0

100.0

15.7

12.7

12.7

11.6

10.7

7.8

10.9

83.2

85.9

66.8

86.6

88.7

90.7

67.7

0.2

0.2

0.0

0.7

0.3

0.7

0.5

0.2

0,2

0.0

1,3

0.2

1.0

0.2

Male12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

100.0

100.0

100.0

100.0

100.0

100.0

100.0

13.4

12.9

9.5

11.2

10.9

6.7

13.3

85.5

86.0

90.1

85.6

88.7

90.9

Female12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.9

100.0

100.0

100.0

100.0

100.0

100.0

...

_

...

...

...

...

,..

...

...

18.2

12.6

16.1

12.1

10.5

9.1

80.6

,85.7

63.5

87.7

66.6

90.4

0.2

0.2

0.0

0.0

0,4

0.4

0.6

1.5

0.4

0.2

0,4

0.0

0.17

16years . ,. . . .

17years . . . . . .

Standard errors

Both sexes 12-

12years . . . . . .

13years . . . . . . .

0.53

1.25

0.98

0.93

1.15

0.79

0.72

0.55

0.59 0.16

1.38

1.15

0.93

1.25

0,66

0.74

0.72

0.13

0.14

0.00

0,40

0.19

0.56

0,31

0.36

0.39

0.11

0.56

0.17

0.36

0.26

1.47

1.70

1.37

1.81

1.48

1.31

0.76

1.73

1.78

1.40

1.83

1.47

1.46

0.76

0.20

0.19

0.00

0.78

0.21

1.00

0.06

0.48

0.41

0.11

1.08

0.17

0.72

0.13

.. .

.. .

. . .

. . .

. ..

. ..

. . .

2.02

1.51

1.86

1.52

1.35

1.16

1.89

1.79

1.64

1.44

1.24

1.32

0.18

0.21

0,00

0.00

0,31

0.45

0.46

0.64

0.27

0.19

0.32

0.00

.. .

. . .

.. .

. ..

. . .

.. .

40
Tablo 18. Number and percent distribution of youths aged 12-17 whose teeth have not been straightened by whether or not parents thought the youths’ teeth

need to be straightened, according to race, sex, and age: United Statest 1966-70—Con.

Race, sex, and age

Parents reported need

for tooth strai~htening

Percent distribution

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

. . .

. ..

. ..

. ..

.. .

. ..

. ..

,.

. ..

. ..

. ..

..

.

. .

. .

.. .

.

.. .

...

9.5

=

8.7

6.o

12.2

13.0

10.5

6.9

9.3

10.7

9.0

16.5

7.8

8.7

1,2

9.7

6.7

3.0

8.0

18,2

12.1

12.2

1.12

1.98

1.57

2.62

1.80

3.16

2.30

1.62

4.62

2.16

4.20

3.19

3.45

1.18

1.33

—

3.17

2.05

2.12

2.72

4.17

4.69

89.9

90.8

93.5

86.3

87.o

88.8

93.1

90.0

88.4

91.0

81.6

92.2

89.7

96.7

89.9

93.3

96.o

90.9

81.8

87.9

87.8

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

Standard errors

1.18

2.04

1.77

2.64

1.80

3.36

2.30

1.67

4.72

2.16

4.42

3.19

4.09

1.18

1.34

3.17

2.74

1.76

2.72

4.17

4.69

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.6

0.5

0.5

1.5

0.0

0.8

0.0

0.7

1.0

0.0

1.9

0.0

1.8

0.0

0.4

0.0

1.0

1.1

0.0

0.0

0.0

0.31

0.46

0.53

0.83

0.00

0.70

0.00

0.58

0.92

0.00

1.37

0.00

1.43

0.00

0.26

0.00

1.04

1.04

0.00

0.00

0.00
Tabla 19. Number and parcent distribution of youths aged 12-17 whose teeth have not been straightened bv whether cmnot parents

thought the youths’ teeth need to be straightened, according to race and annual family income, with standard errors of the

estimates: United States, 1966-70

Race and annual

family income

Estimated number

ofyouths in thousands . . . . . . . . . . . . . . . . . . . . . .

Total 1

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$8,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . ..OO . . . . . .

White

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999

$10,000-$14,999” ::::::::::: :::;;;::;::::;;::;;

$15,0000rmora . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - . - .

Black

Allincomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$8,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

II Parents reported need for tooth

Total

20,151

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

100.0

straightening

E

2,344 17,602

11.6

11.3

9.2

10.2

12.4

14.7

11.3

10.0

12.0

12.6

9.3

10.6

12.5

14.8

11.6

9.8

9.5

9.1

9.1

8.6

11.7

11.0

5.8

11.0

Percent distribution

87.4

88.0

90.3

89.2

85.8

84.5

87.0

89.2

86.9

86.B

90.1

88.8

85.7

84.4

86.6

89.3

89.9

90.0

90.6

90.8

B7.5

89.0

94.2

89.0

59

0.3

0.1

0.2

0.2

0.7

0.1

0.6

0.0

0.3

0.2

0.2

0.2

0.7

0.1

0.6

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

Not

reported

146

0.7

0.6

0.3

0.4

1.1

0.7

1.1

0.8

0.8

0.4

0.4

0.4

1.1

0.7

1.2

0.9

0.6

0.9

0.3

0.6

0.8

0.0

0.0

0.0

1Includes data for “Othar races,” which are tIOt shown separately.

42
Table 19. Number and percent distribution of youths aged 12-17whose teeth have not been straightened bywhether or not parents

thought the youths’ teeth need to be straightened, according to race and annual family income, with standard errors of tha

estimates: United States, 1966-70 –Con.

Race and annual

family income

Total 1

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan $3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$8,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000.$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rm0re . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

White

All incomes, . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.essthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000.$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Black

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000.$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000.$14,999. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Parents reported nead for tooth

straightening

Total

Yes No Don’tknow Not

reported

Standard errors

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

0.45

1.31

1.10

1.14

0.89

1.18

1.13

1.82

0.53

1.97

1.47

1.20

0.96

1.24

1.14

2.04

1.12

1.73

1.69

2.37

3.59

2.56

5.34

6.10

0.47

1.41

1.06

1.27

1.00

1.27

1.19

1.77

0.59

2.03

1.49

1.35

1.06

1.32

1.23

1.98

1.18

1.89

1.86

2.44

3.49

2.56

5.34

6.10

0.13

0.12

0.13

0.13

0.49

0.08

0.33

0.00

0.16

0.20

0.19

0.15

0.52

0.08

0.34

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

0.16

0.37

0.22

0.18

0.27

0.39

0.39

0,54

0.17

0.39

0.28

0.20

0.28

0.41

0.41

0.65

0.31

0.56

0.30

0.55

0.81

0.00

0.00

0.00

I Includes data for “other races: which are not shown separately.

#

43
Table 20. Number of youths aged 12-17 whose teeth have not been straightened andtheaverage Treatment Priority lndex(TPl) per

youth, by race, sex, and whether or not parents thought the youths’ teeth need to restraightened, with standard errors of the

estimates: United States, 1966-70

t

Parents reported

Total 1

need for tooth

Both

straightening Male Female

sexas

Estimated number of

youths in thousands . . . . . . 19,999 10,213 9.786

All youths . . . . . . . . . . . . .

Yes . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . .

Don’t know . . . . . . . . . . . . . . .

Notreported . . . . . . . . . . . . . . .

Allyouths . . . . . . . . . . . . .

Yes . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . .

Don’tknow . . . . . . . . . . . . . . .

Notreported . . . . . . . . . . . . . . .

1

White

Both

Male Female

Both

sexes sexes

16$70 8,710 8,259 2,928

Average TP I

Black

Male I

Female

1,441 I 1,486

I Standard errors

s

0.15 0.15 0.18

0.34 0.44 0.34

0.14 0.13 0.17

1.04 1.76 2.31

1.36 1.55 1.69

1 Includes data for ‘#other races,” which are not shown SePara@lY.

- min

44
Table 21. Number of youths agad 12-17 whose teeth have not been straightened andtheaverage Treatment Priority lndex(TPl) per

youth, byrace, sex, and whether or not youths have been told by dentists that their teeth need to restraightened, with standard

errors of the estimates: United States, 1966-70

Dentists have said

teeth need to be

straightened

Estimated number of

youths in thousands . . . . . .

Al[ youths . . . . . . . . . . . . .

Yes, . . . . . . . . . . . . . . . . . . .

No, . ., .,, . . . . . . . . . . . . .

Not reported . . . . . . . . . . . . . . .

Allyouths . . . . . . . . . . . . .

Yes . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . .

Notreported . . . . . . . . . . . . . . .

Total 1

TFBoth Male Female

sexes

9,999 10,213 9.786

5.1

8.7

4.9

4.8

Both

sexes

16,970

White I

Black

Average TP I

Standard errors

m

4.8

9.7

4.7

3.7

0.12

IL

0.21

1.19 2.16

0.14 0.24

0.91 1.49

5.1

9.5

4.9

3.8

0.22

0.90

0.22

1.97

1Includes data for “other races: which are not shown separately.

45
Table 22. Number of youths aged 12-17 and average Treatment Priority Index (TPI) per youth, byrace, sex, andwhetheror not the

youths' teeth have been straightend, with standard errors of the estimates: United States, 1966-70

Reported tooth

straightening

Estimated number of

youths in thousands . , . . . .

All youths . . . . . . . . . . . . .

Yes . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . .

Not reported . . . . . . . . . . . . . . .

Allyouths . . . . . . . . . . . . .

Yes . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . .

Notreportad . . . . . . . . . . . . . . .

Total 1 II White I Black

TFl Both

Male Female

Both

Male Female

Both

sexes sexes

Male Female

sexes

22,170 11,196 10,974 19,094 9,676 9,418 2,961 1,459 1,502

Average TPI

1-5.0 5.1

4.1 4.5

5.1 5.2

5.8 5.8 %33%!15

Standard errors

3.9

4.6

0.21

0.12

0.21

6.4

5.1

0.22

4.85

0.22

1 includes data for “other races,” which are not shown separately.

46
Table 23. Number andpercent distributionsIf ycmths aged 12.17whose teeth have nOtbeen straightened bywhether OrnOtthey thOught their 0wnteethneedt0

restraightened, according tOsexand age, with standard errOnOf the estimates: United States, 1966-70

Self-reported need

for tooth straightening

Sex and age Totall

Yes NO Don’t know Not

reported

18.3 73.9

.

71.6

73.7

74.2

74.8

74.0

75.6

74.7

8othsexes 12-17 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100.0 7.6 0.2

100.0

100.0

100.0

100.0

100.0

100.0

100.0

20.1

17.6

17.8

19.0

19.6

15.5

17.9

8.2

8.4

7.8

5.9

6.3

8.8

7.3

0.1

0.3

0.2

0.3

0.1

0.1

Male12-17yeara . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1

100.0

100.0

100.0

100.0

100.0

100.0

100.0

19.4

16.7

17.2

19.6

20.4

13.9

18.8

74.4

74.9

76.8

74.5

71.8

76.7

73.1

6.2

8.0

6.8

5.9

7.6

9.4

7.9

0.4

0.2

0.2

Femsde12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.2

20.9

18.6

18.4

18.3

18.8

17.3

0.43

100.0

100.0

100.0

100.0

100.0

100.0

. . .

68.6

72.3

72.6

75.2

76.3

74.4

10.4

8.9

8.8

5.9

4.9

8.1

0.2

0.2

0.2

0.6

—

0.2

0.08

Standard errors

Bothsexes12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.68 I 0.45

12Vears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14yeara . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17yearc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.14

1.03

0.81

1.05

0.98

1.43

0.51m

1.36 0.s4

1.44 1.02

1.53 0.92

1.29 0.76

1.79 1.23

1.91 1.09

0.66 0.48

1.83 1.07

1.57 1.12

1.96 0.94

2.07 1.0s

2.76 2.02

2.71 1 .B6

0.94 0.62

0.0s

0.20

0.12

0.16

0.12

0.10

0.08

. .

..

. .

..

. .

..

Male12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

1.29

1.46

1.76

1.77

1.68

1.49

0.87

0.00

0.36

0.17

0.00

0.24

0.00

0.10

. .

..

..

. .

..

. ..

Female12-17years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

L

2.14 1.33

2.02 1.46

2.57 1.67

2.26 0.92

1.66 1.03

1.96 1.27

2.12

1.38

1.64

1,89

1.57

2.11

—

0.18

0.17

0.17

0.33

0.00

0.22

..

. .

...

. ..

...

...

1 ,nclude* d~~~for ##0th8r races,” which are not shown separatelvo

47
Table 24. Number of youths per 1000 youths aged 12-17whose teeth have been straightened, bysexand annual family income, with

standard errors of the estimates: United States, 1966-70

Annual family income

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

All incomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lessthan$3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$6,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,(300.$14,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -.

Unknown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Both sexes I

Male Female

Number per 1,000 youths

T

107.0 96.4

19.9 21.0

34.5 34.1

63.4 47.5

99.7 75.8

136.0 128.2

291.5 271.8

154.5 147.8

Standard errors

6.90

4.52

5.73

6.36

7.71

16.10

29.93

29.16

7.21

10.25

7.13

11.08

9.48

17.95

28.55

37.52

117,8

18.9

34.9

78.8

127.6

143.3

313.3

162.3

8.35

10,25

9.34

8.29

13,22

18.24

39.45

41.29

48
APPENDIX I A

ASSESSMENT OF OCCLUSION AND TRAINING

OF EXAMINERS

On the form used to record dental findings on

sfimplc youths examined during 1966-70, a

recorder either wrote down the measurements

obtained for various occlusal components or

circled printed values corresponding to the

measurements. The examination documents

were reviewed daily for completeness and legibility. The form was processed on an IBM Optical

hlark Page Reader, Model I, which entered the

examination data directly on punchcards.

After the data recorded on the forms had

been put on punchcards, they were transferred

to magnetic tape. As the final step in data

processing, an edit program was used to search

for impossible codes and inconsistencies. Each

record that failed an edit was printed out for

review. A correction was made by the survey’s

dental advisers.

Proceduresfor Assessmentof Occlusion

1. Buccal segment relation.–This assessment

describes the anterior-posterior relation of the

teeth in the lower arch with the teeth in the

upper arch. Nfost often the score is based on the

relation of the permanent upper and lower first

molars. When the permanent molars were

absent, not fully erupted, or misshaped because

of extensive decay or fillings, the primary molars

or the permanent canines and premolas

wtm used to determine the buccal segment

relation. For assessment purposes, the position

of the upper cuspid is regarded in the same way

that the position of the mesiobuccal cusp is

when the upper first molar is present.

With the teeth resting together, the right and

left sides are assessed separately. To enable a

right-angle view of the area, a mouth mirror may

be used. The schematic drawings that foIlow

serve as a scoring guide.

A. Permanent molars.-Buccal Aspect–Right

Side

1.

2.

3.

4.

Mesial severe (more than cusp-to-cusp

mesial).—A m&ial positioning of the

lower molar beyond a cusp-to-cusp

deviation.

Mesial moderate (cusp-to-cusp mesial

or less).—A mesial positioning of the

lower molar resulting in a cusp-to-cusp

relation.

Normal. -Normal relation, mesiobuccal

cusp of upper molar in the buccal

groove of the lower molar.

CD@ CIKxK?

Distal moderate (cusp-to-cusp distal or

less).–A distal positioning of the lower

49
molar resulting in a cusp-to-cusp relation.

m+4’

‘t t

5. Distal severe (more than cusp-to-cusp

distal).–A distal positioning of the

lower molar beyond a cusp-to-cusp

deviation.

B. Primary molars.–The assessment is made

by observing the position of the distal

surface of the primary lower second molar

in relation toprimary upper

matic drawing

scoring guide.

7

Ant. !mm+ Ant. -3mm

the distal surface of the

second molar. The schethat follows serves as a

Buccal Aspect— Right Side

9

Fl:sh

10

Post. -3mm Post. 3mm+

Primary 1. Lower is anterior to upper by 3 mm. or

more.

Primsry 2. Lower is snterior to upper but less than 3

mm.

Primsry 3. Lower is flush with upper.

Primary 4. Lower is posterior to upper but less than

3 mm.

Primary 5. Lower is posterior to upper by 3 mm. or

more.

2. Posterior Crossbite.–This is a measure of

buccal-lingual deviation in the bicuspid and

molar areas. Both primary and permanent teeth

are included in the appraisal. To simplify the

assessment it is assumed that the upper tooth

has deviated. The entire tooth must be deviated,

not merely rotated, as far as or beyond a

cusp-to-cusp relation (see drawings below). The

scores that are recorded are the number of upper

teeth in buccal crossbite and the number in

lingual crossbite. The totals are entered on the

form in the designated spaces.

Buccsl Crossbite Normal Lingual Crossbite

&Htip ‘ingu Buccal

3-4. Incisor relation.–This assessment is

made only when the permanent central incisors,

at least one upper and one lower, are present

and fully erupted. When fully erupted permanent central incisors are not present, a mark is

made in the “not applicable” space on the form.

A.

B.

Upper anterior overjet or lower anterior

overjet.—With the teeth occluding, the

distance from the most anterior labial

surface of a permanent lower incisor to

the most anterior labial surface of an

upper incisor is measured with a Boley

gauge. The measurement is made parallel

to both the occlusal and the midsagittal

planes. The measurements are rounded to

the nearest whole millimeter and recorded

in the appropriate box (“overjet” for

overjet of the upper incisors and “mandibular protrusion” for overjet of the lower

incisors). Since upper overjet and lower

overjet are mutually exclusive, N.A. (not

applicable) is marked for the one not present. An edge-to-edge bite is recorded as

O-O for the mandibular protrusion box,

N.A. for the overjet box, N.A. for overbite, O-Ofor openbite, and code 3 for the

incisor vertical relation.

Anterior overbite or openbite.—The

measurement, in millimeters, of the vertical overlap of the incisal edges of the

upper incisors (overbite) or the vertical

space between the incisal edges of the

upper and lower incisors (openbite) is

made with a Boley gauge.

50
When overlapping is present, a pencil mark

is made on the permanent lower right or

left central incisor to indicate the extent

of overlap. The distance from the incisal

edge to the pencil mark is measured,

rounded to nearest whole millimeter, and

entered on the form in the “overbite”

space.

When openbite is present, the vertical

space separating the incisd edges of the

upper and lower central incisors is measured and that measurement is entered on

the examination form in the “openbite”

space.

When lower overjet occurs with anterior

crossbite, N.A. is marked for openbite,

overbite, and the vertical incisal relation.

When it is difficult to measure upper or

lower overjet, edge-to-edge bite, or anterior crossbite because of the presence of

rotated or displaced anterior teeth, the

examiner uses his judgment to select the

set of measurements and codes that best

describe the vertical and horizontal incisor

relations. When indicated, the condition is

described on the examination form under

“Remarks.”

C. Incisor vertical relation.–This assessment

is made in conjunction with the overbite

or openbite measurement. When lower

overjet is measured, the most applicable

box is checked for item 18.

The appropriate code number is marked to

describe the location of the line on the lower

incisor (the incisal third, 0-1/3; the middle third,

1/3-2/3; the gingival third, 2/3-3/3). If the line

would appear on tissue below the gingival

margin of the lower incisor or if the lower

incisors are in contact with the soft tissue of the

palate [impinging overbite (E)] , it is coded as

Tis or Imp. oh., respectively.

If an openbite is present, the code number 1,

2, or 3 is marked to correspond with the

measurement recorded for openbite.

5. Malaligned teeth.–A count is made of the

number of teeth rotated about 45° or displaced

about 2 mm. from a presumed ideal alignment.

Next, a count is made of the number of teeth

rotated more than 45° or displaced more than 2

mm. from the ideal. In the upper arch, anterior

teeth are counted before posterior teeth. The

same procedure is repeated for the lower teeth.

The totals for each segment are entered in the

appropriate spaces on the form.

Calculation of Treatment Priority Index

Figure I reproduces a form on which the

examination data are entered to calculate the

Treatment Priority Index (TPI). Directions for

its use follow:

1. Observe the first molar relation and place a

check mark in the column heading that

applies.

2. On the left-hand margin circle the appropriate measurement for the horizontal incisor

relation. If this measurement is 2-4 mm., it

is considered normal with weight zero.

3. On the left-hand margin also circle the

appropriate score for vertical incisor relation and for tooth displacement. An upper

incisor overbite from zero to two-thirds is

considered normal with weight zero. Displacement scores of O and 1 are discarded

with weight zero.

4. Find the appropriate weights for the first

three items at the intersection of the row

and column and enter them in the column

on the right.

5. Transpose the constant for the designated

column to the right.

6. Circle the appropriate scores for posterior

crossbite, and transpose the weights to the

right-hand column.

7. Add up the right-hand column to obtain

the Treatment Priority Index.

Training Examiners

Each of the 6,757 sample youths who received dental examinations during 1966-70 was

examined by one of seven dentists. The dentists

included two senior examiners, designated 1 and

2, who trained and supervised the other examiners, designated 3-7.

Sample youths were not assigned randomly or

equally to the various examiners. At most survey

51
—

(6) Distoclusion N (7) hlesioclusion

e

u

t

r

0

FIRST

MOLAR RELATION

u

=

s~

$

u

.-

:

—.

~.(j

1.4

1.0

.6

.4

.2

Syndrome

Type

u

0

v

.-$

.

.

Weights

Choose appropriate column

mm

9+

(1) Upper Overjet 9

2.0

1.4

1.0

.6

.4

.2

3.4

2.5

1.8

1.1

.6

.3

5.4

4.0

2.8

1.8

1.0

.4

.

.4

1.0

1.8

2.8

4.0

5.4

—

4.8

2.4

.9

—

2.4

4.8

7.9

.2

.4

.9

1.2

1.8

2.4

3.1

4.1

4.9

9.3

6.9

4.8

3.0

1.7

.8

1o+

10+

8.0

5.1

2.9

1.3

1.3

5.9

4.8

3.0

1.7

.8

5.4

4.0

2.8

1.8

1.0

.4

3.4

2.5

1.8

1.1

.6

.3

Retrognathism

.2

.4

.6

1.0

1.4

2.0

—

2.9

1.5

.5

.3

.6

1.1

1.8

2.5

3.4

—

3.8

2.0

.7

.8

1.7

3.0

4.8

6.9

9.3

1.3

2.9

5.

8.0

10+

1o+

—

8.0

4.1

1.5

.8

1.7

3.0

4.8

6.9

9.3

—

6.2

3.2

1.1

.3

.6

1.1

1.8

2.5

3.4

3.8

2.0

.7

.2

.4

.6

1.0

1.4

2.0

2.9

1.5

.5

.4

1.0

1.8

2.8

4.0

5.4

—

4.8

2.4

.9

J. o

(2) Lower OverJet 1

2

3

3+

Prognathism

Overbite

(3) Overbite in Bite 5 crown Y thirds 3/3+

Uc

Eo 2/3-3/3

6.2

3.2

1.1

.-

:5 0-2/3

Et’

n

NORMAL

s Score O <2 1.5

2.9

4.9

2.0

3.8

6.3

3.2

6.2

10+

4.1

8.0

1o+

3.2

6.2

1o+

2.4

4.8

7.9

2.0

3.8

6.3

1.5

2.9

4.9

2-4 Openbite

(4) Openblte in

mm.

4+

2

3

4

5

6

w

.1

.2

.3

.5

.7

1.0

1.3

1.7

2.0

.1

.3

.5

.8

1.1

1.5

1.9

2.5

3.0

.3

.7

1.2

~8

3.9

4.9

6.2

7.7

.4

1.1

1.9

3.0

4.3

5.9

7.7

9.7

1o+

.3

.7

1.2

1.9

2.8

3.9

4.9

6.2

7.7

.2

.4

.9

1.2

1.8

2.4

3.1

4.1

4.9

G

.1

.3

.5

1:;

1.5

1.9

2.5

3.0

z

.1

.2

.3

.5

.7

1.0

1.3

1.7

2.0

~ Count teeth rotated

about 45°0r dis.

;: placed about 2 mm.

an

Is distoclusion

and/or posterior

Crossbite max.

gu to buccal

u“ Count teeth rotated

.cZ >45°0r displaced

g: more than 2mm x 2

PRESENT

/

YES \

.— ~

Max. Max.

?xpansion Collapse

;yndrome Syndrom

F Total (O, 1 no

3 score) ;

.

9

9+

;ONSTANT 5.17

_

_ll_

2.7:

.

1’.. —

1.5(

_

4

0.2: 1.50 5.17

8)&Od MAX. TO No.

O,EZC BUCCAL —

‘c n*- Weight 01.11 .6 al:c:

.~aMAX. TO No. 1

011[ 21 2

:5:% LINGUAL

Weight o .3 1.0 2.?

iUM OF WEIGHTS IS TREATMENT PRIOR

5 6 7 more

2.2 —3.5 —

5.0 —6.9 T

4[ 51 6 Imore

4.2 6.5 9.4 10

FY INDEX

Figure 1. Calculating form for deriving the Treatmant Priority index.

locations youths were examined by only one either 1 or 2 or, as occurred at two locations, by

dentist–3, 4, 5, 6, or 7. At 14 of 40 locations, both 1 and 2. Thus the senior dentists examined

however, a small subsample was examined by relatively few sample youths. The number and

52
percent distribution of youths examined by each

dentist follow:

Number of

Percent

Dentist

distribution of

sample youths

sample youths

examined

examined

7 dentists ,,, ,,. . 6,757 100.0

1 . . . . . . . . . . . . . 236 3.5

2 . . . . . . . . . . . . . 302 4.5

3 . . . . . . . . . . . . . 1,055 15.6

4 . . . . . . . . . . . . . 448 6.6

5 ., ,0.,,. . . . . . 1,689 25.0

6 . . . . . . . . . . . . . 1,472 21.8

7 ,. 0,,.., . . . . . 1#555 23.0

Most examinations completed by the senior

dentists resulted from a planned series of replicate examinations. As a rule, the findings of the

senior dentists were included in the sample

youth’s examination record, and the findkgs of

the dentists with whom the senior dentists were

paired were kept separate. The primary aim of

the replicate examinations was to correct any

examiner divergence from the accepted examination procedures.

Throughout the replicate examinations, the

senior dentist completed his examination first,

while the other dentist was absent, and dictated

his findings to a trained recorder. Then the other

dentist completed his examination, and the

senior dentist recorded the findings. Appreciable

interexaminer differences as well as any procedure that diverged from the accepted one were

discussed and, if indicated, either resolved or

corrected while the sample youth was still

present. The findings originally recorded by the

examiner were not altered.

To indicate the level of agreement on the TPI

and its component measures, interexaminer differences are shown in table L The direction of

disagreement that occurred is shown by positive

or negative numbers. A positive number indicates that findings of the senior dentists were

higher than those of the other dentists, and a

negative number indicates the opposite.

The replicated TPI scores of the senior dentists and of the other dentists were exactly the

stime for about 27 percent of the examinations.

Further, about 55 percent of the scores differed

by no more than 1.0. Agreement on the component measures of the TPI ranged from a high

of about 95 percent for buccal crossbite to a low

of 24 percent for tooth displacement. But of the

replicated tooth displacement scores, only about

54 percent differed by more than 1.0.

The data do not indicate that the senior

dentists tended to assign either generally higher

or lower scores than the other dentists. Three of

the distributions in table I have a higher percentage of positive than of negative scores, while the

reverse is true for the four other distributions.

The percentage of positive scores for openbite

was much higher than the percentage of negative

scores, but only 11 of the sample youths had

openbites.

The results of the replicate examinations

indicate that the level of examiner agreement

was not as high during the survey of youths as it

was during the survey of children.G The lower

level of agreement during the survey of youths is

at least partly due to the fact that the variability

of tooth displacement scores, and therefore of

TPI scores, is greater among youths than among

children. For instance, about 26 percent of U.S.

youths aged 12-17 have tooth displacement

scores greater than 7, but orLIy about 2 percent

of children 6-11 have scores that high. And

about twice as many youths (25.1 percent) as

children (11.4 percent) have TPI scores greater

than 7. Thus there is a greater probability of

wider examiner disagreement occurring for these

two measures during the examinations conducted on youths than during those conducted

on children.

FORTRAN Program for Computing TPI Scores

TPI scores may be computed by using either

the manual calculating form (figure I) or the

computer program printed below, which closely

follows the arithmetic of the form. Another

computer program, which appears in an earlier

publication,5 has a printing error in statement

20; it produces somewhat different results than

the following program.

The subroutine TPIS is called from a main

program which reads in the data and prints the

results. Input is as follows:

A. Set-up and title card

Col. 1 punch 1 if congenitally lost

tooth scores are to be included

53
Table 1. Percent “distribution of interexaminer differences in the Treatment Priority Index (TPI) and its components

on replicate dental examinations: Health Examination Survey, 1966-70

Difference in score

(senior dentist minus other dentist)

Mean difference . . . . . . . . . . . . . . .

Standard deviation of the difference . . . . .

Number of replicate examinations . . . . . .

Ail replicate examinations . . . . . . .

-60r less . . . . . . . . . . . . . . . . . . .

-!5 . . . . . . . . . . . . . . . . . . . . . .

-4 . . . . . . . . . . . . . . . . . . . . . .

-3 . . . . . . . . . . . . . . . . . . . . . .

-2 . . . . . . . . . . . . . . . . . . . . . .

-1 . . . . . . . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . . .

6ormore . . . . . . . . . . . . . . . . . .

TPI

0.22

2.73

391

100.0

3.1

1.5

1.3

4.6

10.0

13.3

26.3

15.1

8.7

6.4

3.8

2.1

3.8

Component score

I I I I

--i

Posterior

Upper Tooth

crossbite Over- Openanterior displacebite bite

Lingual Buccal

overjetl ment

0.10

0.67

399

100.0

—

—

—

0.5

3.2

89.7

3.0

1.3

1.3

0.8

0.2

-0.02

0.29

399

-0.06

0.79

384

-0.03

0.78

375

Percent distribution

100.0

—

—

—

—

0.5

3.0

94.7

1.3

0.5

—

—

—

100.0

—

—

0.3

0.3

3.1

18.2

60.7

15.4

1.6

0.5

—

—

100.0

—

0,3

1.9

17.9

62.7

16.3

0.8

0.3

—

—

F

0.94 2.67

11 408

100.0

9.1

9.1

36.4

45.4

100.0

1.5

1.5

4.4

7,6

11.8

11,5

24.0

10.3

12.0

6.4

3.7

1.2

4.2

‘Too few youths with a Ioweroverjet measurement were included in thereplicate examinations topermit an assessmentof the

interexaminer agreement for the component score.

in the calculations. If not,

leave blank.

Col. 2-4 blank

Col. 5-80 any alphanumeric message or

title

B. Punching format for cards

Col. 1,2 upper anterior overjet in mm

Col. 3 lower anterior overjet in mm

Col. 4 overbite in crown thirds

Col. 5 openbite in mm

Col. 6

COL 7

Col. 8

Col. 9, 10

Col. 11, 12

Col. 13, 14

number of congenitally missing

incisors

distoclusion score

mesioclusion score

number of teeth in posterior

crossbite maxilla to buccal

number of teeth in posterior

crossbite maxilla to lingual

tooth displacement score

C. End of file card (’99’ ;n COI. 1,2)

54
1

c

10

c

4

5

6

7

8

:

c

c

c

c

c

c

;

c

c

c

c

1

5

6

7

8

9

10

11

16

17

18

19

c

c

PGM TO CALL SUBROUTINE TPIS

READS ORTHODONTIC TREATMENT DATA

DIMENSION IDAT(10), NAME(19)

COMMON/LABEL/ TAB(5,4)

READ (5, 1) MSK, (NAME(L), L=1,19)

FORMAT (Al, 3X, 19A4)

WRITE (6, :00) (NAME(L), L=1,19)

FORMAT (t . 19A4)

FROM MARK SENSE CARDS .

READ (5, 3)- (IDAT(L), L=1,1O)

FORMAT (12, 611, 312)

IF (IDAT(1) - 99) 10, 8, 8

99 IN FIRST 2 COLS DF OATA CARD CALLS STOP

IF (MSK) 5,5,4

SET FLAG IF CONGENIATALLY LOST TEETH ARE TO BE USEO.

M=l

GO TO 6

M=O

T = 0.0

CALL TPIS (IOAT, T, M)

WRITE (6, 7) IDAT, T

FORMAT (1X, 1013, F8.2)

GO TO 2

STOP

.EO FROM

ASSEMBLE

ROS, 1,

I PALATE

ENO

SUBROU”

THIS

THIS

MEAS

MEAS

MEAS

MEAS

4 Is

MEAS(4) lNCISbR OPENBITE iN”MM ‘-

MEAS(5) NO. OF CONGEN. MISSING INCISORS O, 1, 2, 3

MEAS(6) OISTOCCLUSION SCOREO-4

MEAS (7) MESIOCCLUSIONSCOREO-4

MEAS(8) POST XBITE, MAX TO BUC

MEAS(9) POST XBITE, MAX TO LING

MEAS(10) TOOTH DISPLACEMENT COUNT

DIMENSION MEAS(10), A(10)

COMMON/LABEL/ TAB(5,4)

OO1J=1,1O

A(J)=MEAS(J)

K = MEAS(6) + MEAS(7) + 1

H = TAB(K,4) + ((A(1) - A(2) - 3.0)**2) ● TAB(K,l)

IF (H-1O.O) 3, 3, 2

H = 10.0

IF (A(4) - 1.0) 9, k, 4

IF (A(4) - 2.0) 5, 6, 6

A(4) = 1.0

GO TO 9

IF (A(4) - 4.0) 7, 8, 8

A(4) = 2.0

GO TO 9

A(4) = 3.0

V = ((A(3) - A(4) - 1.5)**2) ~TAB(K,2)

IF (V -10.0) 11, 11, 10

v = 10.0

X = ((A(8)**2) * 0.14) + ((A(9)**2) * 0.26)

IF (X - 10.0) 13, 13, 12

x = 10.0

0 = (/4(lo)**2)* TAB(K,3)

IF (D - 10.0) 15, 15, 14

0 = 10.0

TPI = H + V + X+ D

IF (MS) 19, 19, 16

IF (A(5)) 19, 19, 17

B = A(5) + 7.0

IF (B-TPI) 19, 19, 18

TPI = B

RETURN

END

BLOCK DATA

COMMON/LABEL/ TAB(5,4)

THE TAB ARRAY IS INITIALIZE BY COLUMNS

DATA TAB/ 0.31, 0.19, 0,11, 0.07, 0,04,

1 0.67, 0.49, 0.39, 0.31, 0.24,

2 0.12, 0,08, 0,05, 0.03, 0,02,

3 0.27, 1.50, 2.72, 3.95, 5.17/

ENO

MAIN

:D BY

2, 3

.

MAIN

55
APPENDIX II

DEMOGRAPHIC AND SOCIOECONOMIC TERMS

Age. –The age recorded for each youth was

the age at last birthday on the date of examination. The age criterion for inclusion in the

sample was defined as age at time of interview.

Since the examination usually took place 2 to 4

weeks after the interview, some of those who

were 17 years old at the time of the interview

had become 18 years old before they were

examined. There were 23 such cases. In the

adjustment and weighting procedures used to

produce national estimates, these 23 were included in the 17-year-old group.

Race. –The race classification recorded by

observation was confirmed whenever possible by

comparison with the race classification on the

youth’s birth certificate. Race was recorded as

“white,” “ black,” or “other.” The last category

included American Indian, Chinese, Japanese,

and all races other than white or black. Mexican

persons were included with “white” unless

definitely known to be American Indian or of

race other thzin white. Blacks and persons of

mixed black and other parentage were recorded

as “black.”

Family income. –The income recorded was

the total income received during the past 12

months by the head of the household and all

other household members related to the head by

blood, marriage, or adoption. This income was

the gross cash income (excluding pay in kind,

e.g., meals, living quarters, or supplies provided

in place of cash wages) except in the case of a

family with its own farm or business, in which

case net income was recorded. Also included in

the family income figure were allotments and

other money received by the family from a

member of the Armed Forces whether he was

living at home or not.

Education of head of household.–The highest

grade that had been completed in school was

recorded. The only grades counted were those

that had been completed in a regular graded

school where persons were given formal education–either public or private school, either day

or night school, and either full-time or part-time

attendance. A “regular” school is one that

advances a person toward an elementary or high

school diploma or a college, university, or

professional school degree. Education in vocational, trade, or business schools outside the

regular school system was not counted in determining the highest grade of school completed.

Geographic regz”on.–For purposes of stratification, the United States was divided into four

broad geographic regions of approximately equal

population. These regions, which correspond

closely to those used by the U.S. Bureau of the

Census, were as follows:

Re@”on

Northeast . . . .

South . . . . . .

Midwest . . . . ..

West . . . . . . .

States Included

Maine, Vermont, New Hampshire, Massachusetts, Connecticut, Rhode Island, New York,

New Jersey, and Pennsylvania

Delaware, Maryland, District of

Columbia, West Virginia, Virginia, Kentucky, Tennessee,

North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi, Louisiana,

and Arkansas

Ohio, Illinois, Indiana, Michigan, Wisconsin, Minnesota,

Iowa, and Missouri

Washington, Oregon, California, Nevada, New Mexico, Arizona, Texas, Oklahoma, Kansas, Nebraska, North Dakota,

South Dakota, Idaho, Utah,

Colorado, Montana, Wyoming,

Alaska, and Hawaii

56
The Survey Design

The sample designs

grams, or Cycles I-III,

tion Survey have been

APPENDIX Ill

STATISTICAL NOTES

for the first three proof the Health Examinasimilar, in that each has

been a multistage, stratified probability sample

of clusters of households in land-based segments.

The successive elements for this sample design

are primary sampling unit (PSU), census enumeration district (ED), segment (a cluster of households), individual household, eligible youth,

and finally, the sample youth.

The 40 sample areasand the segments utilized

in the design of Cycle III were the same as those

in Cycle II. Previous reports describe in detail

the sample design used for Cycle II and in

addition discuss the problems and considerations

given to other types of sampling frames and

whether or not to control the selection of

siblings.8’z2

Requirements and limitations placed on the

design for Cycle III, similar to those for the

design for Cycle II, were that:

1. The target population be defined as the

civilian, noninstitutional population of the

United States, including Alaska and Hawaii,

in the age range of 12 through 17 years,

with the special exclusion of children residing on reservation lands of the American

Indians. The latter exclusion was adopted

as a result of operational problems encountered on these lands in Cycle I.

2. The time period of data collection be

limited to about 3 years for each cycle and

the length of the individual examination

within the specially constructed mobile

examination center be between 2 and 3

hours.

3.

4,

5.

Ancilkuy data be collected on specially

designed household, medical history, and

school questionnaires, and from copies of

birth certificates.

Examination objectives be related primarily

to factors of physical and intellectual

growth and development.

The sample be sufficiently large to yield

reliable findings within broad geographic

regions and population density groups as

well as within age, sex, and limited socioeconomic groups for the total sample.

The sample was drawn jointly with the U.S.

Bureau of the Census, beginning with the 1960

decennial census list of addresses and the nearly

1,900 PSU’S into which the entire United States

was divided. Each PSU is either a standard

metropolitan statistical area (SMSA), a county,

or a group of two or three contiguotis counties.

These PSU’S were grouped into 40 strata, with

each stratum having an average size of about 4.5

million persons. Stratification was accomplished

so as to maximize the degree of homogeneity

within strata with regard to the population size

of the PSU’S, degree of urbanization, geographic

proximity, and degree of industrialization. The

40 strata were then classified into four broad

geographic regions of 10 strata each and then

within each region, cross-classified by four population density classes and classes of rate of

population change from 1950 to 1960. Using a

modified Goodman-Kish controlled-selection

technique, one PSU was drawn from each of the

40 strata.

Generally, within each PSU, 20 census enumeration districts were selected, with the probability of selection of a particular ED proportional to its population in the age group 5-9

57
years in the 1960 census, which by 1966

approximated the target population’ for Cycle

III. A similar method was used for selecting one

segment (a smaller cluster of households) in each

ED. Because of the approximately 3-year time

interval between Cycle II and Cycle III, the

Cycle III sampling frame was updated for new

construction and to compensate for segments

where housing was partially or totally demolished to make room for highway construction or

urban redevelopment. Each of the resulting 20

segments within a PSU was either a bounded

area or a cluster of households (or addresses).

All youths in the appropriate age range who

resided at the address visited were eligible for

inclusion in the sample. Operational considerations made it necessary to reduce the

number of prospective examinees at any one

location to a maximum of 200. When the

number of eligible youths in a particular

location exceeded this number, the “excess”

eligible youths were deleted from the sample

through a systematic sampling technique.

Youths who were not selected as sample youths

in the Cycle III sample, but who had been

examined in Cycle II, were scheduled for examination if time permitted and will be included in

special longitudinal analyses. In addition, a twin

who was deleted from the Cycle III sample was

also scheduled for examination, as in Cycle II, to

provide data on twins for future analysis. These

data are not included in the report as part of the

national probability sample of youths.

The sample was selected in Cycle III, as it had

been for the children in Cycle II, to contain

proportional representation of youths from

families having only one eligible youth, two

eligible youths, and so on, so as to be representative of the total target population. However,

since households were one of the elements in the

sample frame, the number of related youths in

the resulting sample is greater than would have

resulted from a design that sampled youths

12-17 years without regard to household. The

resulting estimated mean measurements or rates

should be unbiased, but their sampling variabilities will be somewhat greater than those from a

more costly, time-consuming, systematic sample

design in which every kth youth would be

selected.

The total probability sample for Cycle III

included 7,514 youths representative of the

approximately 22.7 million noninstitutionalized

U.S. youths of 12-17 years. The sample contained youths from 25 different States, with

approximately 1,000 in each single year of age.

The response rate in Cycle III was 90 percent,

with 6,768 youths examined out of the total

sample. These examinees closely represented the

population from which they were drawn with

respect to age, sex, race, region, population

density, and population growth in area of

residence. Hence it appears unlikely that nonresponse could bias the findings appreciably.

Reliability

The methodological strength of the survey

derives especially from its use of scientific

probability sampling techniques and highly

standardized and closely controlled measurement processes. This does not imply that statistics from the survey are exact or without

error. Data from the survey are imperfect for

three major reasons: (1) Results are subject to

sampling error, (2) the actual conduct of a

survey never agrees perfectly with the design,

and (3) the measurement processes themselves

are inexact even though standardized and controlled.

Of the total sample, 746 were not examined.

Findings for nonexamined youths were imputed

by attributing to them the characteristics of

comparable examined youths. The specific procedure used consisted in inflating the sampling

weight for each examined person to compensate

for nonexamined sample persons at the same

survey location and in the same age-sex group.z

It is impossible, of course, to be certain that the

average number of, for instance, makdigned

teeth per person is the same for the examined

and the nonexamined groups.

Only 11 examined sample youths did not

receive a dental examination. Thus, dental findings were recorded for 6,757 youths who are

classified in table II by age and sex; the

estimated U.S. population aged 12-17 years is

shown in table III by age, race, and sex.

Dental findings for the 11 youths were

supplied by forming pools of examined youths

58
Table 11. Number of sample youths who received a dental

examination, by age and sex: Health Examination Survey,

1966-70

Age Mala Female

12-17 years . . . . . . . . . . . . .

12years, . . . . . . . . . . . . . . . . .

13years . . . . .. m........ . . .

14years . . . . . . .. m........ .

15years . . . . . . . . . . . . . . . . . .

16years . . . . . . . . . . . . . . . . . .

17years . . ..m. .o . . ..m . . . . .

Numberof

sample youths

T

3,538 3,219

642 545

625 582

618 586

612 503

554 535

487 468

Table ill, Estimated number of noninstitutionalized civilian youths

aged 12.17 years, byrace, sax, andaga: United States, 1966-70

Whita Black

Age Total 1

Male I Female Male Female

I

Number in thousands =i:Em 12yeers .,....... ,

I Includes data for “’other races;’ which are not shown 5eParatelY.

with demographic characteristics that matched

those of the unexamined youths. One youth was

randomly selected from each of the 11 pools,

and the missing measurements were assumed to

be the same as those recorded for the randomly

selected, examined youths.

At the close of the survey there were 349

sample youths whose occlusal status had not

been fully recorded. When a sample youth’s

record had only one occlusal measurement

missing, the measurement was imputed. The

imputed value was randomly selected from a

pool of the records of youths with occlusal

characteristics the same as or similar to those of

the youths with the missing measurements.

Sampling and Measurement Error

Several references have been made in this

report to efforts to evaluate both bias and the

variability of the measurement techniques. The

probability design of the survey makes possible

the calculation of sampling errors. Traditionally,

the role of the sampling error has been the

determination of how imprecise the survey

results may be because they come from a sample

rather than from all elements in the universe.

The task of presenting sampling errors for a

study of the type of the Health Examination

Survey is complicated by at least three factors:

(1) measurement error and “pure” sampling

error are confounded in the data—it is not easy

to find a procedure that will either completely

include both or treat one or the other separately, (2) the survey design and estimation

procedure are complex and accordingly require

computationally involved techniques for the

calculation of variances, and (3) thousands of

statistics come from the survey, many for

subclasses of the population for which there are

small numbers of sample cases. Estimates of

sampling error are obtained from the sample

data and are themselves subject to sampling

error, which may be large when the number of

cases in a cell is small or, occasionally, even

when the number of cases is substantial.

Estimates of approximate sampling variability

for selected statistics used in this report are

included in the detailed tables. These estimates

have been prepared by a replication technique

that yields overall variability through observation of variability among random subsamples of

the total sample. The method reflects both

“pure” sampling variance and a part of the

measurement variance.

In accordance with the usual practice, the

interval estimate for any statistic may be considered the range within one standard error of the

tabulated statistics with 68-percent confidence

or the range within two standard errors of the

tabulated statistic with 95-percent confidence.

Expected Values

In tables 14-16, the actual mean Treatment

Priority Index (TPI) per person for each of

59
various demographic variables is compared with

the expected value. The computation of expected values was done as follows:

Suppose it is estimated that in a subgroup

there are Ni persons in the ith age group (i-1,

2, . . . . 7; sum of iV#l). Suppose it is

estimated that the mean TPI per person for

the United States in the ith age-sex group is

Xi. Then the expected mean TPI for the

subgroup is

Comparison of an actual value for, say, a

region, with the expected value for that region is

undertaken o~ the assumption that a meaningful

statement can be made that holds, in some

average way, for all persons in the region. This

may or may not be true. The specified region

may have higher values for younger youths and

lower values for older youths than the values

found in other regions. In that case, an average

comparison will obliterate one or both of these

differentials. In arriving at the general conclusions expressed in the text, an effort was made

to consider all of the specific data, including

data not presented in this report; but it must be

recognized that balancing such evidence is a

qualitative exercise rather than a quantitative

one. The standard error of the difference between an actual and expected value may be

approximated by the standard error of the

actual value.

Small Numbers

In some tables, magnitudes are shown for cells

for which sample size is so small that the

sampling error may be several times as great as

the statistic itself. Obviously in such instances

the statistic has no meaning in itself; it merely

indicates that the true quantity is small. Such

numbers have sometimes been included to convey an impression of the overall story of the

table.

Tests of Significance

Tests of significance for percent and mean

statistics were performed in two ways. The first

was to determine if the difference between two

estimated averages was equal to or greater than

two times the standard error of the difference.

The test assumes, in accordance with usual

practice, that a 68-percent confidence interval

ranges within one standard error of the tabulated statistics and that a 95-percent confidence

interval ranges within two standard errors. The

latter is used as the level of significance in this

report. An approximation of the standard error

of the difference d = A! - y of two statistics x

and y is given by the formula

where SX and SY are standard errors, respectively, of x and y.

For example, table 13 shows that the average

TPI is 5.2 for white males aged 12 and 5.4 for

white males aged 17; the corresponding standard

errors are 0.27 and 0.20, respectively. The

formula yields a standard error of the difference

of Sd = .3360. Since the observed difference

(d= 0.2) is less than twice the standard error of

the difference, it may be concluded that the

mean TPI for white males aged 12 is not

significantly lower than that for white males

aged 17.

The second test was to determine whether the

difference between the estimated actual and

expected values was at least two times the

standard error of the actual value. For example,

for females from families with less than $3,000

yearly income, the difference between the actual

and expected mean TPI scores is 0.5 (table 14),

and the standard error of the actual value is

0.21. Since the difference is more than twice the

standard error, it is statistically significant.

The criterion for significance among geographical regions was more stringent than that

for the other demographic characteristics. To

determine whether the difference between estimated averages for youths in any two of the

four geographic regions was siamificant, the

difference was required to be at least 2.5 times

the standard error.

000

60
APPENDIX IV

THE RELATION BETWEEN TPI SCORES AND

ORTHODONTISTS’ RATINGS OF THE SEVERITY

OF MALOCCLUSION

The Division of Health Examination Statistics

conducted a special study in 1967 to find out

how well orthodontists’ appraisals of the severity of malocclusion in children agree with the

levels of severity indicated by the Treatment

Priority Index (TPI). The study was made

possible by the cooperation of the American

Association of Clrthodontists; the Bureau of

Dental Health, New York State Department of

Health; and thirty practicing, Board-qualified

orthodontists who personally took part in the

study. The National Center for Health Statistics

is especially grateful to Dr. J. A. Saltzman, a

former president of the American Association of

Orthodontists, for his interest in the study and

his support of it.

The clinical judgments used in developing the

estimating equation of the TPI were made by

two orthodontists who examined casts of the

teeth of 375 twelve-year-old children residing in

three Canadian communities.s The present

study was undertaken in 1967 in an attempt to

answer the following questions: How well do

TPI scores reflect the severity of malocclusion

present in youths 15-18 years old? Are the

weights and constants developed to measure the

severity of malocclusion in the Canadian children also suitable for measuring the severity of

malocclusion in the U.S. population which,

unlike that of the three Canadian communities,

is composed of children of many races and with

many ethnic backgrounds? And, lastly, how well

do the clinical judgments of two orthodontists,

staff members of the same orthodontic research

project, represent the judgments of U.S. orthodontists, who are trained in many schools and

practice in various parts of the country?

To begin to answer those questions, plaster

casts of the teeth of some 1,400 youths were

borrowed by the Division of Health Examination Statistics from the New York Bureau of

Dental Health. The youths had been randomly

selected from a sampling frame comprising all

students enrolled during 1963 in grades 10

through 12 in the public senior high schools of

upstate New York. The schools were stratified

according to their location—metropolitan or

nonmetropolitan-and the students were sampled to represent the populations enrolled in

both gTOUpS of schools.g

Impressions of the sample students’ teeth

were taken and the bites were registered in wax.

Pretreatment casts were obtained for most of

those who either had received orthodontic treatment or were receiving it at the time of the

study. The final study group consisted of 1,413

youths, 96.6 percent of the total sample.

After plaster casts of the impressions had

been poured and finished, they were examined

independently by two practicing, Boardqualified orthodontists. Each was instructed to

take certain measurements on the casts and to

record them. Following his examination of each

set of casts, he was asked to make the clinical

judgment whether or not the youth’s malocclusion was so severe that he would be eligible for

orthodontic treatment under the State-aid-tocount y dental rehabilitation program. When the

judgm-ents of the two orthod&tists

they jointly reexamined the set of

differed,

casts in

61
question, and discussed the case until they came

to an agreement.

When the casts were made available for the

present study, they were randomly numbered

and laid out. One or the other of the dental

advisers of the Division of Health Examination

Statistics measured each set of casts, and the

occlusal components that are needed to calculate the TPI scores were recorded. In all, 1,379

casts were measured by the two advisers, and

-114 of them were measured by both advisers.

The measurements were sent to Dr. Robert M.

Grainger, who calculated the TPI scores.

Arrangements were made through the American Association of Orthodontists for 30 practicing, Board-eligible orthodontists from 15

States to examine the casts. The casts were laid

out on tables in a large room at the site of the

Association’s annual meeting in 1967. The following instructions had previously been sent to

the orthodontists that participated in the study.

1. Examine each set of casts quickly but

carefully to determine the degree of handicapping malocclusion that is present.

2. Base your appraisal on how severely health,

function, and esthetics may be impaired.

Only the seriousness of the problem and

the urgency of treatment, not the difficulty

or cost of correction, should enter into

your judgment.

3. Express your judgment of the degree of

handicap by assigning a number from O

through 10. A suggested interpretation of

the scale is shown below:

Scale of

severity Interpretation

o Virtually classic normal occlusion

1 Minor variations for which treatment need is slight

2

3

4 Definite malocclusion but treatment

is a matter of choice

5

6

7 Severe handicap for which treatment is highly desirable

8

9

10 Very severe malocclusion for which

treatment is mandatory

Before each orthodontist began to examine

the study casts, one of the Division’s dental

advisers reviewed and discussed with him the

instructions he was to follow. He then was asked

to practice the procedure by grading 28 casts

randomly removed from the study casts. Finally,

he examined about 50 study casts and graded

the severity of malocclusion that, in his judgment, each represented. The severity rating he

assigned to each set of casts was written down

by a recorder.

The casts were assigned to each orthodontist

in such a way that half of them were graded by a

second orthodontist and the other half by a

third orthodontist. For example, orthodontist 1

started with cast 1 and finished with cast 50. A

second orthodontist graded casts 51 through

100, and a third one graded casts 25 through 75.

Thus, when the last orthodontist had graded the

casts assigned to him, there were 30 sets of

replicated measurements.

After all data for the study had been collected, they were transferred to a magnetic tape.

The information on the tape included the

following: the severity scores of the 30 orthodontists (two for each of 1,379 casts), the TPI

scores based on the two dental advisers’ measurements (one score for each of 1,265 casts and

two scores for each of 114), and codes indicating whether or not the malocclusion of each

of the 1,379 youths was so severe that he would

have been eligible for treatment under the New

York State dental rehabilitation program, if he

had met certain other requirements.

Correlation coefficients were computed for

the paired orthodontists’ ratings and for the

replicated TPI scores. The coefficients for the

orthodontists’ ratings ranged from a low of 0.41

to a high of 0.85, with the median 0.69. The

coefficient for the replicated TPI scores was

0.85.

The number and percent distributions of the

62
30

26

10

6

0

t — Orthodontists’ ratings

--- TPI scores

‘\

‘.

‘\

‘\

\\

‘\

‘\

‘.

01 2345678 9

DIFFERENCES

NQTE.-Tho two TPI scores recorded for om set of caws

,lllh!w,l lIV -13.

50

t

— Orthodontists’ ratings

,%,

., . --- TPI scores

,.LY -..

.-.--->------ I

o 1-3 4.0 7-9 10

RATINGS AND TPI SCORES1

lTPI scores larger than tO am included with score s.+10.

Figure I I 1. Percent distribution of average orthodontists’ ratings

and of TPI scores of 1,379 casts by specifiad intervals: Health

Examination Surveyr 1967.

differences between the paired orthodontists’

ratimzs and of the differences between the

Figure 11. Percent distribution of the differences between 1,379 replicated TPI scores are shown in figure II. A

paired orthodontists’ ratings and between 114 replicated TPI comparison of both the data and the correlation

scores, according to the size of the differences. coefficients suggests that TPI scores are more

❑ Orthodo”tists,rati”gs

~ TP,,cores

99.4

100

90 -

ao

70

60

50

40 -

30

20

10

0

10 10

or

more

aa.3

7-10 7-1o

or

4-10 4-1o 1.10

or

more

RATINGS ANO TPI SCORES

1-1o

or

more

100.0

0.10 0-10

or

more

Figure IV. Percent of 182 children classified .in 1962 New York study as having severe handicapping malocclusions, according to

specified rangesof the severity ratings of orthodontists and of TPI scores: Health Examination Survey, 1967.

63
highly reproducible than orthodontists’ severity

ratings. About one-third of the replicated TPI

scores, but only about one-fifth of the replicated

orthodontists’ ratings, were exactly the same.

Furthermore, about two-thirds of the scores, but

only about one-half of the ratings, differed by

no more than one point. The average difference

between the replicated TPI scores was 1.4, or

0.4 less than that between the replicated orthodontists’ ratings.

The percent distributions both of the averages

of all paired orthodontists’ ratings and of all TPI

scores are shown in figure III. The averages of

the two orthodontists’ ratings for each cast were

used because they are generally more representative of orthodontic opinion than an individual orthodontist’s ratings.

Correlation of the TPI scores with the average

of the orthodontists’ ratings gave a coefficient of

0.62. The coefficients for the scores with the

individual orthodontists’ ratings were 0.57 and

0.55. The smallness of the differences between

the coefficient for the scores with the average

ratings and the median coefficient for the paired

orthodontists’ ratings (0.69 minus 0.62) suggests

that orthodontists can reproduce other orthodontists’ ratings little better than the TPI can.

In the earlier New York study, 204 sample

youths (14.4 percent) were found to have

malocclusions so “handicapping” that the

youths would have been eligible for treatment

under the dental rehabilitation program. The

present study included casts of the teeth of 182

of those youths. Figure IV shows the orthodontists’ severity ratings and the TPI scores that

were recorded for the 182 casts. It will be seen

that 56 percent of the TPI scores were 10 or

more—upward of twice the percentage the

orthodontists graded 10. On the other hand,

75.8 percent of all casts graded 10 by the

orthodontists, but only 65.4 percent of the ones

with TPI scores of 10 or more, were those of the

eligible youths (table IV).

In summary, the findings indicate that the

clinical judgments of orthodontists of the severity levels of malocclusion represented by plaster

casts of the teeth of youths are correlated

almost as highly ~th TPI scores recorded for

the same casts as they are with replicated ratings

by other orthodontists. They further suggest

Table IV, Number and percent distribution of 1,379 casts by

orthodontic treatment approved (New York), according to

specified ranges of severity ratings of orthodontists and of

Treatment Priority Index (TP I) scores: Health Examination

Survey, 1967

Malocclusion severity

scale

Orthodontists’ ratings

Total . . . . . . . . . . . . . . .

o . . . . . . . . . . . . . . . . . . . . . . .

1-3 . . . . . . . . . . . . . . . . . . . . . .

4-6 . . . . . . . . . . . . . . . . . . . . . .

7-9

10 . . . . . . . . . . . . . . . . . . . . . .

TP I scores

Total . . . . . . . . . . . . . . .

o .......................

1-3 . . . . . . . . . . . . . . . . . . . . . .

4-6 . . . . . . . . . . . . . . . . . . . . . .

7-9 . . . . . . . . . . . . . . . . . . . . . .

10ormore . . . . . . . . . . . . . . .

Orthodontic treatment

approved (New York )

EE

Number

364

2

5

43

223

91

182

o

3

21

56

102

2,394

230

738

899

498

29

1,197

31

670

354

88

54

EE

Percent

distribution

. . .

0.9

0.7

4.6

30.9

75,8

. . .

~

0,0

0.4

5.6

38.9

65.4

. . .

99.1

99.3

95.4

69.1

24.2

. . .

~

100.0

99.6

94.4

61.1

34.6

that dentists who have been carefully and

uniformly taught to measure the occlus~ variables used to calculate TPI scores can reproduce

each other’s scores better than orthodontists can

reproduce the severity ratings of other orthodontists. And, finally, the Treatment Priority

Index, compared with the severity ratings of the

orthodontists, more efficiently identified the

casts found in the earlier New York study to

represent very severe “handicapping” malocclusion. That is, 86 percent of those casts were

given both TPI scores and orthodontists’ ratings

of 7 or more, and 98 percent were given both

scores and ratings of 4 or more. But of the casts

found not to represent very severe malocclusion,

only 11.9 percent had TPI scores of 7 or more

and only 41.4 percent had scores of 4 or more.

On the other hand, 22.0 percent of the same

casts were graded 7 or more by the orthodontists and 59.6 percent were graded 4 or more.

64
Thus it would seem that the TPI is at least as of malocclusion, and using it instead of orthoaccurate as orthodontists’ judgments are in dentists’ judgments would result in fewer “false

screwing a large population for very severe cases positives.”

000

65

* U. S. GOVERNMENT PRRiTD?JG OFFICE , 1977 0 - 229-553
Series 1.

Series 2.

Series 3.

Series 4.

Series 10.

VITAL AND HEALTH STATISTICS PUBLICATIONS SERIES

Formerly Public Health Service Publication No. 1000

Programs and Collection fiocedures. –Reports which describe the general programs of the National

Center for Health Statistics and its offices and divisions, data collection methods used, definitions, and

other material necessary for understanding the data.

Data Evaluation and Methods Research. –Studies of new statistical methodology including experimental

tests of new survey methods, studies of vital statistics collection methods, new analytical techniques,

objective evaluations of reliability of collected data, contributions to statistical theory.

Analytical Studies. –Reports presenting analytical or interpretive studies baaed on vital and health

statistics, carrying the analysis further than the expository types of reports in the other series.

Documents and Committee Reports. –Final reports of major committees concerned with vital and

health statistics, and documents such as recommended model vital registration laws and revised birth

and death certificates.

Data from the Health Interview Suruev. –Statistics on illness: accidental iniuries; disability; use of

hospikl, med@l, dental, and other se~ices; and other health-related topics, b&ed on data collected in

a continuing national household iriterview survey.

Series 11. Data from the Health Examination Survey. –Data from direct examination, testing, and measurement

of national samples of the civilian, noninstitutionalized population provide the basis for two types of

reports: (1) estimates of the medically defined prevalence of specific diseases in the United States and

the distributions of the population with respect to physical, physiological, and psychological characteristics; and (2) analysis of relationships among the various measurements without reference to an

explicit ftite:universe of persons.

Series 12. Data j+om the Institutionalized Population Surveys. –Discontinued effective 1975. Future reports from

these surveys will be in Series 13.

Sm.es 13. Data on Health Resources Utilization. –Statistics on the utilization of health manpower and facilities

providing long-term ewe, ambulatory care, hospital care, and family planning services.

Series 14. Data on Health Resources: Manpower and Facilities. –Statistics on the numbers, geographic distribution, and characteristics of health resources including physicians, dentists, nurses, other health occupations, hospitals, nursing homes, and outpatient facilities.

Series 20. Data on Mortality. –Various statistics on mortality other than as included in regular annual or monthly

reports. Special analyses by cause of death, age, and other demographic variables; geographic and time

series analyses; and statistics on characteristics of deaths not available from the vital records, based on

sample surveys of those records.

Series 21. Data on Natality, Marriage, and Divorce. –Various statistics on natality, marriage, and divorce other

than as included in regular annual or monthly reports. Special analyses by demographic variables;

geographic and time series analyses; studies of fertility; and statistics on characteristics of births not

available from the vital records, based on sample surveys of those records.

.

Series 22. Data j%om the National Mortality and Natality Sumeys. –Discontinued effective 1975. Future reports

from these sample surveys based on vital records will be included in Series 20 and 21, respectively.

Series 23. Data j+om the National Survey of Family Growth. –Statistics on fertility, family formation and dissolution, family planning, and related maternal and infant health topics derived from a biennial survey of

a nationwide probability sample of ever-married women 1544 years of age.

For a list of titles of reports published in these series,write to: Scientific and Technical Information Branch

National Center for Health Statistics

r Public Health Service, HRA

Rockville,Md. 20S57

/