Cultural and Psychologic Influences on Treatment Demand H. Asuman Kiyak

Although epidemiologic studies of orthodontic treatment need in the US and other countries have consistently shown moderate to high need among 27% to 53% of children aged 8 to 17, treatment demand is far lower. In particular, ethnic minorities, males, and children in rural communities are less likely to seek treatment. Income and the ability to pay for treatment play an important role in parents' decisions to obtain orthodontic care for their children. Nevertheless, even when treatment is provided at low or no cost, differences are observed in children's perceptions of need, and their demand for treatment. This article discusses cultural and psychologic fac- tors that influence perceptions of need. The role of subjective and objective judgments of attractiveness in the development of body image and self- concept, and the subsequent impact of self-concept in treatment demand are discussed in the context of a model of personality development. In recommending and planning treatment, orthodontists should be aware of the child's self-appraisal, the parents' role in seeking treatment, as well as whether the parent's and child's expectations can be achieved through orthodontic intervention. (Semin Orthod 2000;6:242-248.) Copyright © 2000 by W.B. Saunders Company

O rthodontics has grown rapidly over the past 20 years as a dental specialty, not only

in the United States, but throughout the world. This is not surprising, given the reduction in caries prevalence in children and epidemiologic evidence from many countries that malocclusion is a universal problem. Nevertheless, there is a disparity in demand and access to or thodontic treatment in all countries from which data are available. For example, an analysis of the 1989- 1991 National Health and Nutrition Examina- tion Survey (NHANES III) in the US, using the Index of Treatment Need (IOTN) as an objec- tive measure of or thodontic need, found signif- icant malocclusion problems in children of di- verse ethnic backgrounds.~ This study is valuable

t~)om the Department of Oral and MaxiUofacial Surgery, Uni- versity of Washington, ,Seattle, WA.

Address correspondence to H. Asuman Kiyak, MA, PhD, De- pa,~ment of Oral and MaxiUofacial Surgery, Box 357134, Univer- sity of Washington, Seattle, WA 98195-7134.

Copyright ¢;) 2000 by V< B. Saunde~s Company 1073-8746/00/0604-0007510. 00/0 doi: 10.1053/sodo. 2000.19072

because of the large sample size (7,000) selected to represent a broad cross-section (150 million) of the American public. Among children aged 8 to 11, 51.5% of whites, 53.4% of African Amer- icans, and 27.3% of Mexican-Americans showed moderate-to-definite need for or thodontic care. Among children aged 12 to 17 in this same population, 42.4% of whites, 52.8% of African Americans, and 51.8% of Mexican Americans were determined by the IOTN to have this level of need. The reduced need among older white children was attributed to treatment received in the past; 10.5% had obtained it by age 8 to 11, 27.4% by age 12 to 17. In contrast, the finding that need remained constant in African Ameri- can children as they reached adolescence re- flects the lack of treatment in the interval. The increase in objectively assessed need among Mexican American children reflects both a lack of treatment and increased rates of malocclu- sion with growth. Less than 3% of these ethnic minority children had received care by age 17, compared with 27.4% of white children.

The NHANES III data also revealed differ-

242 Seminars in Orthodontics, Vol 6, No 4 (December), 2000: pp 242-248

Influences on Treatment Demand 243

ences by income status. Children whose families had incomes greater than $50,000 (1990 dollars) were twice as likely to receive t rea tment as those with incomes of $35,000 to $49,000, and 6 times more likely than those with incomes less than $20,000. Although many states provide Medicaid funding for low income children to obtain orth- odontic care, only a small p ropor t ion of chil- dren who qualify actually receive t reatment . Is this a reflection of differential access to orth- odontic t rea tment because of inability to pay, lack of awareness, or differences in perceived need by minority children and their parents, compared with white, non-Hispanic children?

The focus of this article is on cultural differ- ences in esthetic values and need for or thodon- tic intervention, psychologic factors that influ- ence the d e m a n d for t reatment , as well as access to care. Based on the data presented, a model will be p roposed to describe the deve lopment of body image and self-esteem, which in turn is hypothesized to influence t rea tment d e m a n d and cooperat ion.

Ethnic Differences in US Populations

One of the problems in distinguishing ethnic differences f rom socioeconomic disparities is the high correlation between these 2 variables. At least in the Uni ted States, ethnic minorit ies on average are more disadvantaged in terms of income and educat ion than is the majority white populat ion. It is therefore impor tan t to compare populat ions that have been matched on socio- economic status (SES) but differ in ethnicity. Previous research by the author offers such com- parisons and suggests that ethnicity may influ- ence percept ions of attractiveness and need for t reatment, even when controll ing for SES.

In the first study, adults aged 18 to 60 (aver- age age = 30) who were residents of a low- income housing project in a major US city and who qualified for free or reduced fee dental services part icipated in a study examining dental behaviors, attitudes, and esthetic preferences. 2 Respondents included 46 US-born Caucasians and 50 Pacific Asians who had immigra ted to the US within the past 3 years. In this manner , SES was held constant, but cultural influences dif- fered between the US-born whites and recent immigrants whose health behaviors and atti- tudes had been shaped by their native culture

(in this case, Chinese, Vietnamese, and Lao- tian).

Esthetic preferences were assessed with line drawings of female facial profiles that matched the subject 's ethnicity but were manipula ted to represent varied maxil lo-mandibular relation- ships, f rom normal occlusion to vertical excess or deficiency, a retrusive or protrusive mandible or maxilla, and bimaxilla~ y protrusion or retru- sion. Another set of drawings mainta ined the same face but varied dental occlusion (ie, nor- mal, anter ior diastema, anter ior crowding, and crossbite). Research subjects rated each of the 9 profiles and each of the 4 occlusal conditions on a 5-point attractiveness scale, then selected the "most attractive" and "least attractive" faces within their racial group (all interviews and questionnaires were presented in the partici- pant ' s native language which was English, Chi- nese, Vietnamese, or Laotian).

Mthough the drawing of the normal profile was rated most positively by whites, Asians as- signed a higher value to bimaxillary retrusion; in fact, 42% selected this face as most attractive. The white patients also rated bimaxillary retru- sion favorably, but prefer red vertical deficiency in their choice of the most attractive profile. In general, Asian adults used the more positive range in rating profiles than did whites, suggest- ing a greater tolerance of faces outside the "ideal" range of attractiveness. The higher pref- erence shown by Asians for bimaxiIlary retrusion may reflect a novelty effect, or a preference for faces outside their own cultural norms. How- ever, when these ratings were compared with each subject 's own occlusal states, as measured by the T rea tmen t Priority Index (TPI), no cor- relations emerged. Nei ther the individual's over- all need for t rea tment nor specific type of mal- occlusion was associated with facial preferences in the Asian or white samples. It is noteworthy that almost twice as many white adults in this study were found to have clinically significant malocclusion than were Asians, particularly on ratings of overbite (24% v 12% respectively).

A subsequent study examined knowledge and t rea tment expectat ions of 75 middle class chil- dren (mean age 10.85 years) undergoing phase I orthodontics, and those of their parents. 3 Addi- tional data (unpublished) increased the sample size to 84 and the ethnic minori ty sample to 22% of the total. Among other variables, children

244 H. Asuman Kiyak

were asked to rate a series of facial drawings that varied in occlusion, from normal to anterior crowding or diastema, overbite, overjet, and open bite. Ethnic differences again emerged; white children evaluated faces with anterior crowding, diastema, overjet and overbite less fa- vorably than did ethnic minority children.

These observed differences in both studies are noteworthy. That is, by selecting white and ethnic minority research subjects from the same population, and by testing for income and edu- cational similarity, comparisons could be made between ethnic groups independent of SES. In both cases, ethnic minorities appeared to be more tolerant of dental appearance and occlu- sion that was outside the range of "ideal" than were whites. These findings are consistent with studies of body image in young women. Whites have generally been found to be more con- cerned about their body image than African American and Asian American young women. In particular, white women show greater dissatisfac- tion with their weight and more discrepancy between their self versus ideal weight than does the latter group. 5,6 Researchers have attributed this to greater susceptibility to social pressure and narrower definitions of acceptable physical appearance in white American culture.

International Comparisons

Epidemiologic data from other countries using objective measures such as the IOTN are con- sistent with the NHANES III data reported in the introduction. For example, 35% of children aged 9 to 10 have been found to need some form of orthodontic intervention in Denmark, 7 27% to 36% of children aged 9 to 15 in England and Wales, 8 40% of Japanese children aged 15 to 18, '-~ 38% of Turkish children aged 6 to 10,1° and 49% of this same age group in Israel. n Treatment need varies from a low of 27% in some segments of the UK population to 53% in some US pop- ulations. Despite this evidence of significant ob- jective need for treatment, there have been few studies that have examined perceptions of need among children and their parents internation- ally. In US studies, perceived need has been found to be higher in females than in males, greater among whites than among ethnic minor- ities, more among those in urban settings and in

high SES groups. 12,13 In contrast, actual clinical need has been found to be greater for males, and equal across socioeconomic strata and loca- tion. 1~

Cross-cultural differences may also exist in percept ions of attractiveness. For example, Class I is considered to be the most attractive dental occlusion a m o n g white Americans, Class III the least. However, treatment demand is higher among those with Class II than with Class III malocclusion. 14,1-~ In contrast, in a study conducted in Singapore, young Asian respon- dents rated Class III malocclusion as more at- tractive than Class II and those with the former condition were less likely to seek treatment than those with the latter. 16

Patient Demand for Care

Denmark represents a useful model in which to examine the impact of patient and parental de- cision-making when barriers to access are re- moved. Since 1973, the Child Dental Health Service in Denmark has screened for or thodon- tic need and recommended treatment for ap- proximately one third of these children (consis- tent with their epidemiologic data that 35% have severe to moderate need for treatment). Be- cause of the national health benefits available to children under age 18, most of those referred can obtain treatment at no cost if they so desire. Nevertheless, many do not follow through on recommendat ions for orthodontic care. In an interesting follow-up of 841 Danes who had been screened 15 years earlier but had not received treatment during chi ldhood or adolescence, Helm et al found that only 10% had subse- quently sought care? 7,1s Another 20% had not obtained treatment but perceived a need; these respondents also reported that their lack of treatment had affected their social interactions and body image during adolescence, especially if the malocclusion was severe (ie, overjet greater than 7 ram). These data are useful in describing the impact of not seeking treatment; the major- ity of patients do not subsequently seek it when costs must be covered out-of-pocket, whereas a minority of patients perceive that their lack of follow-up has affected their quality of life in adulthood.

Influences on Treatment Demand 245

Psychologic Aspects of Appearance To what extent does physical appearance affect one ' s quality of life, and which is more impor- tant, subjective percept ions or objective ratings by peers or strangers? A substantial body of re- search suggests that physical attractiveness is an asset and leads to positive halo effects and a self-fulfilling prophecy that "what is beautiful is good." Perkins and Lerner m found that facial attractiveness ratings by self and others are the best predic tor of psychosocial funct ioning in ad- olescents (mean age = 11.8). This supports their earlier study of sixth graders, in which they found that children who were independent ly rated as high in physical attractiveness also re- ceived more favorable competence and behavior ratings by their teachers than did children who were judged by others to be less attractive. 9° Even in children as young as preschool age, physical attractiveness can affect teachers ' judg- ments. In another study, preschool teachers rated their students as socially compe ten t or dysfunctional. ~1 An independen t sample of adults unfamiliar with these children also rated photos of these children in terms of aggression, attractiveness, and social competence . The re- searchers found a high correlat ion between the 2 groups in ratings; both teachers and indepen- dent adult raters consistently evaluated the less attractive children as less socially competent . A meta-analysis of 113 empirical studies of attrac- tiveness and competence in children and adults found a consistent trend, that attractive people are perceived to be more compe ten t than less attractive targets, and that these percept ions are related to objective measures of competence by independen t evaluators who know the target persons. 92 However, this relationship holds only for children, not for adults. It may suggest that attractive children have a built-in advantage as they interact with the world outside their nu- clear family. They are given more at tention and help in learning new skills than less attractive children. Nevertheless, as they mature , they must show real skills and knowledge that are gained through their own initiative, regardless of the help they have or have not received f rom others.

To what extent does dental appearance influ- ence self and social j udgmen t s of attractiveness? The majority of Americans believe that dental

appearance is "vet y important" in social interac- tions. 2~ Studies conducted in the US and the UK have found that children with a normal dental appearance are j udged by peers to be bet ter looking and more desirable as friends; such chil- dren are also j udged by teachers as more com- pe ten t and more intelligent. 24,25 Specific types of malocclusions have been found to be more sus- ceptible to social stigma, including those in the anter ior region such as crowding, overjet greater than 6 mm, and deep bite greater than 7 mm. 26,27 A US study found that oveIjet is the most significant predic tor of or thodont ic de- mand, especially in children referred for treat- m e n t by their parents. 2s

It is not surprising that a desire to improve one ' s appearance is a pr imary reason for seeking or thodont ic a n d / o r surgical intervention. ~9-32 Parental suppor t for or thodontics often emerges f rom their hope that the child will conform to society's ideals of facial attractiveness. As a re- suit, their decision is based less on the severity of the malocclusion, and more on a generalized desire to improve the child's dental esthetics and self-esteem. Sometimes these parental ex- pectations are u n r e a l i s t i c . :<27,~°--~2 A recent study compar ing parents and children in the US and Turkey suggests that or thodont ic expectations may differ both across cultures and between par- ents and children. 32 Using a quest ionnaire com- parable to the one used by Tung and Kiyak with 84 child-parent pairs, 3 the researchers inter- viewed 35 children referred for reduced fee or thodont ic care at Ankara University and their parents, as well as 42 child-parent pairs in a public dental clinic in Seattle. A 1B-item mea- sure of t rea tment expectat ions was adminis- tered, represent ing 4 factors: oral function, self- image (primarily esthetic), social interactions, and health.

Significant differences emerged across the 3 groups for bo th parents and children. Parents in all 3 groups expected the greatest improvement in esthetics but Turkish parents rated this signif- icantly higher. They also expected more im- p rovement in their child's social life and general heal th after or thodontics than did the other 2 groups. Similarly, Turkish children expected more benefits f rom orthodontics, especially in the areas of oral function, esthetics and social interactions, than did the o ther 2 groups. Differ- ences were also observed between middle and

246 H. Asuman Kiyak

low SES samples, such that both parents and children in the public health clinic expected more social benefits f rom orthodontics. It is dif- ficult to determine whether these expectations are based on a real understanding of the changes that orthodontics can produce or if it is wishful think- ing on the part of these children and their par- ents that such a dental intervention can have far-reaching effects.

Impact of Appearance on Self-Concept and Self-Esteem

Personality theorists f rom Freud 33 to Erikson, 34 as well as psychologists who have focused on cognitive deve lopment such as Piaget -~5 have em- phasized the role of body awareness in the de- ve lopment of self-concept. At the same time, o ther people ' s qualitative reactions and re- sponses to our appearance influence the devel- o p m e n t of body image and self-esteem. Of course, physical appearance is not the only fac- tor that determines our self-identity or others ' reactions to the self, especially as the child ma- tures. Academic and athletic achievements, the ability to interact with peers, teachers, and oth- ers all come to play an increasingly impor tan t role in our self-esteem. Tha t is one reason why most measures of self-esteem are mult idimen- sional; body image represents just one dimen- sion. This may also explain why most studies of psychologic reactions to or thodontics and or- thognathic surgery have found improvements in self and others ' ratings of the pat ient 's dental- facial appearance , but not in overall self-esteem and social c o m p e t e n c e ? 6,37

Another impor tan t step in the deve lopment of self-esteem is the child's internalization of others ' j udgmen t s of his or her attractiveness. In a longitudinal study of adolescents followed for 1 year, self-esteem and anxiety were associated with the child's subjective assessment of his or her own physical attractiveness, not with objec- tive appraisals by teachers and p e e r s Y Children who underra te their own facial attractiveness have been found to score lower on measures of self-esteem than children who rate themselves at or above others ' ratings. -~9

It is not surprising that adults are also j udged on the basis of their physical attractiveness more than other factors when the rater has had no pr ior contact with the individual. Suppor t for

this conclusion comes f rom a study in which a sample of white undergraduates were given ma- nipulated data on hypothetical job applicants, varying the ethnicity, appearance, and speech style of these applicants, and asking judges to rate them for their acceptability for a particular job. 4° The best predic tor of judges ' ratings was appearance , followed by speech style. Not sur- prisingly, ratings of likeability and desirability as a dating par tner are greater when the target person is physically attractive. In another study, undergradua te students were asked to rate vid- eo taped images of same-aged persons on these characteristics. 41 Physical attractiveness was a sig- nificant predictor of preferences. An even more specific indicator, facial beauty, was the best de- te rminant of ratings of likeability and desirability as a dating partner. This is noteworthy, given that judges had no personal familiarity with the target subjects.

Implications for Orthodontic Treatment Demand

This discussion suggests the deve lopment of a model of pat ient demand for or thodont ic treat- ment . As presented in Figure 1, the earliest in- fluences on a child's body awareness are a par- ent or o ther caregiver's physical and emotional interactions with the child. As the child's world expands, teachers and peers respond to his or her physical appearance. These messages may reinforce each other and the child's subjective assessment, or may conflict with the child's own perceptions. By integrat ing these appraisals (and in some cases, by ignoring objective judg- ments) , the child develops a cognitive represen- tation of the self, a body image. As discussed earlier, ethnic and cross-cultural factors also play a role in the deve lopment of a body image (Fig 1).

Although body image has been shown in this article to represent an impor tan t c o m p o n e n t of self-concept (or self-identity), it is not the sole factor. Especially as the child reaches adoles- cence, his or her accomplishments in academics and athletics, as well as social competence (eg, ability to play well with peers, showing appropri- ate classroom behaviors) have a significant im- pact on others ' reactions to the child. These responses f rom others in turn influence the child's self-concept and self-esteem (ie, one ' s

Influences on Treatment Demand 247

Figure 1. Psychologic influ- ences on orthodontic treat- ment demand.

assessment o f self-worth). To the e x t e n t that a

chi ld holds h imse l f o r he r se l f in h igh regard ,

t he re is g rea te r se l f -acceptance and a desire to

main ta in the status quo. For such ch i ld ren , an

o r thodon t i s t ' s r e c o m m e n d a t i o n or a pa r en t ' s

e n c o u r a g e m e n t to ob ta in o r t h o d o n t i c t r e a t m e n t

may be fut i le because the chi ld is satisfied with

his or h e r appea rance , no m a t t e r how far outs ide

the r ange o f " ideal" or even n o r m a l his denta l -

facial fea tures may lie. In such cases, if the ch i ld

is f o r ced by paren t s to receive t r ea tmen t , coop-

e ra t ion d u r i n g active t r e a t m e n t and a d h e r e n c e

to long- t e rm t r e a t m e n t r e c o m m e n d a t i o n s may

suffer.

In contrast , for many ch i l d r en whose self-

accep tance is no t very high, the desi re to c h a n g e

one or m o r e c o m p o n e n t s o f se l f -concept may be

great. Those who can ident i fy the i r ma locc lus ion

or p o o r den tofac ia l d i s h a r m o n y as the source o f

the i r dissatisfaction are m o r e h ighly mo t iva t ed

to ob ta in o r t h o d o n t i c t r e a t m e n t and are be t t e r

risks for long- te rm c o o p e r a t i o n and a d h e r e n c e

to t r e a t m e n t p ro tocol . It b e h o o v e s the or th-

odont i s t to r ecogn ize these d i f ferences , to iden-

tify ch i l d r en who a t t end the init ial o r t h o d o n t i c

consul t willingly versus those who are c o e r c e d by

paren ts or o t h e r c o n c e r n e d adults, as well as

those whose own and whose paren t s ' mot ives are

unreal is t ic and incons i s t en t with the type o f mal-

occ lus ion p resen ted . This requ i res an h o n e s t

discussion with the child, pe rhaps with the par-

e n t l i s ten ing bu t n o t pa r t i c ipa t ing in the session.

Q u e s t i o n i n g the chi ld a b o u t his or h e r areas o f

sat isfaction with the face and o t h e r aspects o f the

self, mot ives for and c o n c e r n s abou t t r ea tment ,

and w h e t h e r o r n o t the chi ld unde r s t ands his or

h e r responsibi l i t ies d u r i n g each phase o f treat-

m e n t can p r e v e n t fa i lure in the case o f ch i l d r en

who are u n p r e p a r e d or, m o r e impor tant ly , those

who have few intr insic mot ives for seek ing or th-

odon t i c in te rven t ion .

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