The pain experience and psychological adjustment to orthodontic treatment of preadolescents, adolescents, and adults David Ferry Brown, BBSc, PhD,* and Roger G. Moerenhout, MDSc** Wollongong and Melbourne, Australia Age-related changes in psychological measurements of pain and well-being were studied in patients undergoing full fixed appliance orthodontic treatment. A longitudinal series of four questionnaires was used to obtain measurements of these factors after the separation phase of treatment, banding (2 to 7 days after separation), the first adjustment visit (3 to 4 weeks after placement of full fixed appliances), and the second adjustment visit (3-4 months after banding was completed). The results suggest an interaction between the phases of treatment and reported pain and psychological well-being and significant differences in the response profiles of the adolescent age group (14 to 17 years) compared to the preadolescent (11 to 13 years) and adult groups (18 years and older). These findings did not appear to be due simply to group differences in the use of analgesics, class of malocclusion, or type of full fixed appliance used. The profile comparisons indicated that the adolescent age group generally reported lower levels of psychological well-being and higher levels of pain during the phases of treatment examined. Consistent with these results was the finding that the adolescents differed from the preadolescents and adults in the quality o! the pain experience reported during treatment. The results indicate an age difference in adjustment to fixed orthodontic therapy, which suggests that adolescents are more vulnerable to undesirable psychological effects of treatment. (AMJ ORTHODDENTOFACORTHOP1991;100:349-56.)
D u r i n g adolescence a person becomes extremely concerned about physical appearance, especially as it relates to the reaction of significant others, t Physical change, especially change deviating from notions of the ideal, assumes special importance during this period of development. 2 Considering that acceptability of occlusal condition has been shown to be significantly related to acceptability of a general physical appearance, 3 it is no surprise that adolescents form the largest age group seeking treatment to correct a socially unacceptable occlusal condition. Indeed, orthodontists have estimated that 80% of their patients seek their services out of concem for esthetics rather than for health and function. ~ However, patients often feel embarrassed or believe that they are being ridiculed by their peers because of the appearance of orthodontic appliances. 5"6This reaction to some forms of orthodontic therapy assumes special importance for the adoles-
*Department of Psychology, University of V~bllongong, Wollongong, New South Wales, Australia. **Departmentof Orthodontics,Universityof Melbourne. Melbourne, Victoria, Australia. 811124666
cent whose concept of self can be highly susceptible to peer opinions. 7 The peer group often serves as a point of reference and gives the adolescent another evaluation of self. g That there may be a relationship between the age of the patient and undesirable psychological effects of orthodontic treatment was shown in an earlY study b y Haynes. 9"~°Active orthodontic treatment appeai'ed to be discontinued much less frequently in patients 5 to 9 years of age (11.5%) than in patients of i5 years and older (79.9%). This finding caused Haynes to suggest that discontinuance of treatment may be due to essentially psychological and emotional factors. Pain from the appliance and the intrusion of treatment into the patient's daily social life were seen as major causes of discontinuance of treatment. Undesirable psychological effects of therapy do not appear to be a problem in adult orthodontic patients. In a survey of 33 adult patients between 18 and 58 years of age, Tayer and Burek'J found that nearly 74% indicated that they had initial fears concerning peer reaction to their treatment. However, Tayer and Burek concluded that fixed appliance therapy for the adult patient, although initially embarrassing, was soon ac-
349
350
Bro~ivl a n d Moerenhout
cepted and that negative concerns and fears were short lived. Similar findings were reported by Baum. 12 Where the younger patient is concerned, positive -psychological adjustment to treatment does not appear to be quite as apparent as in the adult. More than 50% of 218 patients less than 18 years of age and undergoing active appliance therapy or in full-time retention were reported to have experienced anxiety concerning treatment. ~3Anxiety increased significantly with the age of the patient and was reported more often by girls than by boys. In a study of 50 7- to 14-year-old boys and 50 6- to 14-year-old girls, Maj et al/4 found that 77% of the children reported a high degree of difficulty in psychological adjustment to the treatment. Forty-two percent of the sample reported that the appliance was painful. Distress was especially noted in the older children. However, Lewis and Brown, 15 in a study of 100 British children 9 to 18 years of age, found that only 25% reported that they were anxious about wearing orthodontic appliances. These authors concluded that the level of anxiety induced by appliance therapy was lower than that reported by Maj et al., perhaps because of increasing acceptance by peers. If the age of the patient is a significant factor affecting psychological adjustment to therapy, however, then the difference in the age range between these two studies confounds any direct comparison. While anxiety about wearing an orthodontic appliance may affect a person's psychological adjustment to treatment, the pain experience is also a contributing factor. Most of the discomfort associated with fixed appliances appears to be experienced during the initial 4-week adjustment period or coincides with appliance adjustment." After placement of a fixed appliance, only two of a sample of 30 patients 11 to 30 years of age reported no pain. ~6 There was a decreasing, although uneven, gradient of pain over the 16 days that followed placement of the appliance. During the first 5 days after placement, less discomfort was reported by the under16-year age group that by the over-16-year group. These findings may not be explained by a simple relationship between type of orthodontic appliance used and reported pain. In a study of patients undergoing active orthodontic therapy (69% with fixed appliances, 12.5% with removable appliances, and 18.5% with a combination of the two), there was no significant difference in reported pain intensity between the subjects wearing fixed appliances and those wearing removable appliances. ~7However, 28% reported a wish to discontinue appliance wear because of pain intensity, and 39% reported that the worst thing about appliance wear was the intensity of the pain. These research findings suggest that there may well
Am. J. Orthod. Dentofac. Onhop. October 1991
be a nonlinear relationship between age and psychosocial adjustment to fixed appliance therapy. However, the different age ranges in the various studies reviewed confound any direct comparative conclusions. The aim in the present study is to compare in a systematic manner the psychosocial adjustment of preadolescents, adolescents, and adults to fixed-appliance orthodontic therapy. METHOD
Subjects were patients of l I years or older who were candidates for orthodontic intervention with full fixed appliances. Specialist orthodontists practicing in the greater Melbourne area were asked to approach consecutive patients who were scheduled to undergo treatment within a 6-month period. A total of 76 patients accepted the invitation to participate in the study. Informed consent was obtained from the parents of juvenile patients and directly from the adult patients. PROCEDURE
A longitudinal series of four questionnaires was used for the data collection. Adult subjects and juvenile subjects and their parents were given both a verbal and a written explanation of the research study and instructions for completion of the questionnaire. The subjects were instructed to complete the first questionnaire (time 1) the morning after the separation phase of treatment. This questionnaire also contained a written explanation of the research study and the instructions for completion. The second questionnaire (time 2) was completed on the morning after initial banding. That was when at least one arch wire had been placed in the patients' orthodontic appliance to begin initial tooth movement. The third questionnaire (time 3) was completed on the morning after the first adjustment, and the final questionnaire was completed on the morning after the second adjustment (time 4). In summary, time 1 (TI) refers to 1 day after separation; time 2 (T2) to 1 day after banding, which was 2 to 7 days after separation; time 3 (T3) to 1 day after adjustment, which was 3 to 4 weeks after full fixed appliances had been placed; and time 4 (T4) to 1 day after adjustment, which was 3 to 4 months after banding was completed. Each participating orthodontist was asked to complete a 16-part treatment modality inventory for each of his or her patients volunteering to participate in the study. Information was collected on whether single or both arches ~ere receiving treatment, the type of initial arch wire (Multiflex, 0.012-inch stainless steel, 0.014inch stainless steel, nitinol, other), the type of appliance used (Begg, edgewise, other), whether extractions had been required, ratio of bonds to bands, the type (mod-
Volume 100 Number 4
ules, brass ligature, other), and the time of separation before banding. Information was also collected on any medication prescribed before placement of bands. Patients' dental malocclusion was recorded according to Angle's classification. ~s Demographic data on each patient were collected by means of the questionnaire at time 1 only. Subjects were instructed to complete the questionnaire on the morning after each ph.ase of treatment. The adult subjects and both the subjects and their parents in the case of the preadolescent and adolescent samples were instructed in completion of the questionnaires. The parents were instructed to assist the subjects in the completion of the questionnaire only if necessary. Included in each questionnaire was a version of the McGill Pain Questionnaire (MPQ). 19 The MPQ is a rating scale that measures intensity and quality of pain and has been shown to have high reliability and construct validity. Patients are asked to select, among 20 sets of pain descriptors, the words that best describe their pain experience at the present time. The pain descriptors in each set have been scaled from least to greatest pain intensity. This scale has been shown to be reliable when self-administered, as in the case of adults, or when administered by a second party, as in the case of parent to child. A subject's score is derived from the number of words chosen and the rank order of those words and is expressed as the total pain-rating index (PRI). The adjectives used as pain descriptors have been demonstrated to be suitable for children from 9 years of age on. 2° Children as young as 9 to 12 years were able to select a variety of pain descriptors from a given list, and no appreciable difference within this age range was found. 2° Further data were collected regarding any medication taken and location of the pain experience. The subject's psychological well-being was measured by a 20-item scale devised by Kammann and Flett. 2~ This scale is a measure of a person's current level of general happiness or sense of well-being and is negatively correlated with somatic complaints. A subject's well-being score is a summation of his or her responses to 20 adjectives describing psychological mood states. Subjects report how they feel at the present time by responding on a five-point scale from "not at all" to "all the time" to the adjectives describing their mood state. This scale has been reported to have high internal reliability (ct = 0.88) and construct validity. 2~ Changes in a subject's engagement in recreational and social activities were measured by a modification of an index developed for subjects undergoing orthognathic surgery. 22 This index comprised eight recreational activities (e.g., swimming, jogging, golf) and
Pain experience and psychological adjustment to treatment
351
eight social activities (e.g., working on hobbies, going to parties, visiting friends). The items covered activities commonly engaged in by the age groups sampled. The frequency of activities was measured in terms of "no participation" to "regular participation." A subject's activity score was a summation of the frequency of these activities over the past few weeks. RESULTS
Of the total sample, 79% (n = 60) completed all questionnaires. The subjects were classified into the following age groups: (1) a preadolescent group 11 to 13 years of age (n = 23); (2) an adolescent group, 14 to 17 years (n = 25); and (3) an adult group, 18 years and over (n = 12). The percentage breakdown of the sample (group 1, 38%; group 2, 42%; and group 3, 20%) was considered to be a fair reflection of the age ratio of patients normally seeking orthodontic treatment. Forty percent of the patients were men or boys, and 60% were girls or women. The internal reliability of the psychometric scales, as assessed by Cronbach's alpha, was never less than 0.85 for the pain scale and 0.74 for psychological wellbeing. Before differences between age groups could be tested, it was considered necessary to determine whether any significant relationships existed between certain confounding factors and the response variables of pain, psychological well-being, and recreational/social activities. Differences between various factors and the dependent variables over the time periods sampled were evaluated by repeated-measures analysis of variance. No significant differences were found for any of the response variables between male and female subjects, between the treatment mechanics groups, or between Angle classification groups at any of the time periods sampled. Differences between the age groups over the time periods sampled for the response variables of pain, psychological well-being, and recreational/social activities (Table I) were tested by profile analysis. -'3 Profile analysis tests whether the three age groups have identical patterns of highs and lows for the response variable over the phases of treatment. If there is no interaction between age group and phase of treatment for the response variable tested, the hypothesis of parallel profiles is accepted. The level of statistical significance was set at p --< 0.05. For each response variable, the profile of the preadolescents was first compared with that of the adults, and then the profile of these subjects was compared with the adolescent profile. This independent set of comparisons tests the hypothesis that orthodontic treht-
352
Brown attd Moerenhout
Am. J. Orthod.Dentofac.Orthop. October1991
Table I. Group means and standard errors for each response variable over the time periods sampled
After separation Mean Pain (PRI) Group I Group 2 Group 3 Psychological Well-b6ing Group 1 Group 2 Group 3 Recreational Activities Group I Group 2 Group 3 Social Activities Group 1 Group 2 Group 3
I
After banding
SE
Mean
8.87 15.44 9.97
2.09 2.77 2.27
1.71 1.30 1.63
I
First adjustment
SE
Mean
11.74 22.06 10.29
2.31 3.07 2.07
0.20 0.23 0.26
1.53 1.18 1.65
1.36 1.40 0.88
0.09 0.09 0.12
1.48 1.72 1.52
0.07 0.07 0.12
SE
Mean
8.61 11.32 10.08
1.77 2.42 1.82
7.72 ! 3.52 10.33
1.69 2.16 2.32
0.26 0.24 0.32
1.51 1.59 1.40
0.25 0.22 0.33
1.83 1.23 1.52
0.19 0.20 0.32
1.41 1.29 0.98
0.09 0.09 0.16
1.42 1.44 0.96
0.09 0.07 0.14
1.39 1.37 0.89
0.07 0.08 0.12
1.60 1.56 1.53
0.08 0.09 0.14
i.60 1.67 1.40
0.09 0.09 0.16
1.51 1.67 1.35
0.07 0.08 0.15
ment may be more traumatic for adolescents than for preadolescents and for adults. No significant difference was found between the pain profiles of the preadolescent and adult subjects. However, a significant difference (F = 3.54; df = 3,55; p = 0.02) was found when the pain profile of the adolescents was compared with the profiles of the preadolescent and adult subjects. The profile analysis indicated that there was an interaction between age group and reported pain over the phases of treatment. The level of the pain profile for the adolescents was significantly (F = 10.69; df = 1,57; p = 0.002) laigher after the banding phase when compared with the pain responses of the preadolescent and adult subjects. Further, X2 analyses indicated no significant association between the reported use of analgesics and age groups over the time periods sampled, suggesting that the difference in reported pain between the groups may not be simply a reflection of different usage of analgesics. No significant difference was found between the well-being profiles of the preadolescent and adult subjects. The well-being profile of the adolescents did sign!ficantly differ (F = 2.71; df = 3,55; p = 0.05) from the profiles of the preadolescent and adult subjects. The profile analysis indicatedan interaction between age groups and psychological well-being over the phases of treatment. The level of psychological wellbeing for the adolescents was significantly (F = 7.63; df = 1,57; p = 0.008) lower after the banding phase than the level of well-being observed in the preadolescent and adult subjects. Similar to the pain data, these
I
Second adjustment I
SE
results suggest an interaction between age group and psychological well-being over the phases of treatment and a difference in the adolescents' level of responses compared with those of the preadolescent and adult subjects. A small decrease in social and recreational activity between TI and T2 was seen in the adolescent group as compared with the preadolescents and adults, but this was not significant. The frequency of use for each of the 20 sets of pain descriptors was examined for each age group at the postseparation and postbanding phases of treatment. While the total pain score (PRI) on the MPQ is an indication of quantitative differences in reported pain, differences in the use of pain-descriptor sets indicates differences in the quality of the pain experience. Following the criterion set by Terezhalmy et al.,-'~4 the sig nificant frequency of use for each set of pain descriptors was set at greater than 50% of usage for each age group. With the use of this criterion, a profile description of the quality of the pain experienced by each age group can be made at the postseparation and postbanding phases. At the postseparation phase (Fig. 3), both the preadolescent and adult groups had a 9, 16 set profile, and the adolescent group had a 5, 9, 16, 18 profile. At the postbanding phase (Fig. 4), the preadolescent group had a 5, 9, 10, 16, 18 profile, the adult group showed a similar profile with the exclusion of set 18, and the adolescent group had a 4, 5, 6, 9, 10, 16, 17, 18, 20 profile. These subclasses of pain descriptors covered the
Volume I00
Pain experience and psychological adjustment to treatment
353
Number 4
23.00
-
22.00
2.00
--
/
20.00
18.00
:o
-
16.oo=
i
= 14,00
-1.00
--
12.00
10.00 8.00
X
I1 - 13year$ old
|
14 - 17 years old
$
18+ years old
6.00
I
I
TI
T2
I
"'/
"f/I TI
I
T3
I T2
I T3
//
T4 Phase o [ T r e a l m e n t
Phase of T r e a t m e n t
WELL-BEING
PAIN
Fig. 2. Mean psychological Well-being for each age group across phases of treatment.
Fig. 1. Mean pain level for each age group across phases of treatment.
*
90
II • 13 years old
o
14 - 17 years old
•
18 ÷ years old
o o
70
i o
~
6o 50
•
~ ~-.~
o 40
/,,
}
20
I 1
I T4
I 2
I 3
I 4
I 5
6
7
8
Subclasses
• = ~ 9 10 11 12 13 14 15 16 17 18
---I 20
of Paln Dcscr|ptors
TREATMENT
I'tlASE 1
Fig, 3. Percentage of each age group using subclasses of pain descriptors the day following the separation (T1) phase of treatment. Subclasses: 1, flickering-pounding; 2, jumping-shooting; 3, prickinglancinating; 4, sharp-lacerating; 5, pinching-crushing; 6, tugging-wrenching; 7, hot-searing; 8, tinglingstinging; 9, dull-heavy; 10, tender-splitting; 11, tiring-exhausting; 12, sickening-suffocating; 13, fearfulterrifying; 14, punishing-killing; 15, wretched-blinding; 16, annoying-unbearable; 17, spreading-piercing; 18, tight-tearing; 19, cool-freezing; 20, nagging-torturing.
354 Brown and Moerenhout
Am. J. Orthod. Dentofac. Orthop. October 1991 ,
11 - 13 ~ e a r s o l d
o
14 - 17 y e a r s o l d
•
IS + ~¢ars o l d
1°° T 9O
i
o
70
~
60
)
50
~g.
40 30 20
0
2
3
4
5
6
7
8
9
10 11 12 13 '/4
5 16 17 18 19 20
Subclasses of Pain Descriptors TREATMENT PHASE 2
Fig. 4. Percentage of each age group using subclasses of pain descriptors the day following the banding (1"2) phase of treatment. Subclasses: I, flickering-pounding; 2. jumping-shooting; 3, pricking/ancinating; 4, sharp-lacerating; 5, pinching-crushing; 6, tugging-wrenching; 7, hot-searing; 8, tinglingstinging; 9, dull-heavy; 10, tender-splitting; 11, tiring-exhausting; 12, sickening-suffocating; 13, fearfulterrifying; 14, punishing-killing; 15, wretched-blinding; 16, annoying-unbearable; 17, spreading-piercing; 18, tight-tearing; 19, cool-freezing; 20, nagging-torturing.
sensory (subclasses 1 to 10), evaluative (subclass 16), and miscellaneous (subclasses 17 to 20) dimensions of the pain experience defined by Melzack. 19 It is interesting to note that the affective dimension (subclasses 11 to 15) of the pain experience was not prominent in any of the profiles. All age groups tended to select pain descriptors from the sensory dimension. However, the adolescent group tended to use a greater number of sets from this dimension than did the other age groups; this is especially evident after the separation phase of treatment. DISCUSSION
The results indicate that the adolescents generally reported a higher level of pain (PRI) after all phases of treatment (Fig. 1). This difference is clearly noted after the banding phase. These pain indices were taken the day after the appliance-adjustment phases, which have been suggested as being associated with most discomfort after treatment." All groups reported some level of pain after the treatment-adjustment phases. After the banding phase, however, only the adolescents showed a higher level of pain intensity than that reported by Melzack 19for dental pain (mean pain level, 19.5). Fur-
thermore after the separation and banding phases of treatment, the adolescents showed greater use of descriptors from the sensory dimension in describing their pain. This is not surprising, considering the high correlation (r = 0.89) reported by Melzack between the number of descriptors chosen and the PRI score. The descriptor profiles are similar to other findings, suggesting that patients with acute pain tend to use more descriptors from the sensory dimension and fewer from the affective dimension than do patients with chronic pain. 2~ This was to be expected in view of the fact that the present pain measurements reflect the patient's reaction the day after the banding-adjustment phase of treatment and may not reflect a chronic pain condition. The higher level of pain (PRI) reported by the adolescent group did not appear to be due to a difference in treatment characteristics or to differences in the use of analgesics. It is possible, however, that levels of reported pain are confounded with, or mask, other affective reactions to treatment. Reported pain can often be a somatization of either anxiety or depression. 16 In this situation, reported pain may be the patient's attempt to translate feelings of anxiety or depression into a tangible physiologic problem.
Voh,me tO0
Number 4
The preadolescents and the adults showed a similar profile for psychological well-being over the phases o f treatment. Compared with the other age groups, the adolescent profile was characterized by lower wellbeing after the banding phase (Fig. 2). In view o f the high negative correlation ( - 0.84) reported between the well-being scale used in the present study and the Beck Depression Scale, low levels o f psychological wellbeing may well reflect a greater degree o f depression. 2~ These differences in psychological adjustment are consistent with the higher pain levels reported by the adolescents during the phases of treatment. The lower level o f well-being seen in the adolescent group at the 4-month treatment phase tends to suggest that this group may have long-term difficulty in adjustment. Although it is important to note that the mean well-being scores generally apepar within levels given for a normal adult population (mean = 1.43, SD = 1.08), the group scores do indicate relative differences in psychological adjustment to treatment. The poorer adjustment to treatment shown by the adolescent group m a y be due to their stage o f psychological development. Adolescents may seek orthodontic treatment out o f concern for their physical appearance. 3 However, the form o f treatment mechanics used in fixed-appliance orthodontic therapy has been shown to cause patients some concern. T M The higher levels o f pain and the lower levels o f psychological well-being reported by the adolescent group may suggest a more traumatic reaction to treatment than seen in the other age groups. It can be suggested that, perhaps because o f their critical period o f psychological development, adolescents find it more difficult to adjust to the initial effects o f fixed-appliance orthodontic therapy. Although the degree of this reaction to treatment does not warrant undue alarm, the results do suggest that further research is needed to examine whether psychological preparation, in the form o f brief counseling, may be o f benefit to some adolescent patients about to undergo fixed-appliance therapy. Although systematic changes were found between the pain and well-being profiles o f the age groups sampled, this study has certain limitations on the interpretation o f results. It may well be that the similarity in the profiles o f the preadolescents and adults is due to some parents assisting their children in the completion of the questionnaires. In this situation, the parents may project their own concerns regarding the immediate psychological effects o f treatment. If this had happened, then the indices for the preadolescents may have been confounded with adult responses. In this situation, however, greater heterogeneity than that observed might have been expected for the response measures within
Pah~ experience and psychological adjustment to treatment
355
the preadolescent group. It must also be noted that the pain descriptor profiles are based on previous research suggesting a cut-off point o f more than 50% o f subjects choosing a given word. These profiles may well change substantially, given a different cut-off criterion.
REFERENCES
1. Tierno MJ, Arts D. Responding to self-concept disturbance among early adolescents: a psychological view for educators. Adolescence 1983;18:577-84. 2. Schonfield WA. Inadequate masculine physique as a factor in personality development of adolescent boys. Psychosom Med 1950;12:49-54. 3. Brown DF, Spencer AJ, Tolliday PD. Social and psychological factors associated with adolescents' self-acceptance of occlusal condition. Community Dent Oral Epidemiol 1987;15:70-3. 4. Rosenberg M. Malocclusion and cranio-facial malformations: self-concept implications. Paper presented at the Workshop on Psychological Aspects of Craniofacial Malformation. Hilton Head, S.C., October 1974. 5. BreeceGL, Nieberg LG. Motivations for adult orthodontic treatment. J Clin Orthod 1986;10:166-71. 6. ShawWC, Meek SC, Jones DS. Nicknames, teasing, harassment and the salience of dental features among school children. Br J Orthod 1980;7:75-80. 7. Coleman E. Counselling adolescent males. Am Personnel Guidance J 1981;60:215-9. 8. Steinberg L, Silverberg SB. The vicissitudes of autonomy in early adolescence. Child Dev 1986;57:841-51. 9. Haynes S. Discontinuation of orthodontic treatment relative to patient age. J Dent 1974;2:138-42. 10. Haynes S. Discontinuation of orthodontic treatment in the General Dental Service in England and Wales, 1972-1979. Br Dent J 1982;152:127-9.
! 1. Tayer Btl, Burek MJ. A survey of adults' attitudes toward orthodontic therapy. AM J OR'roOD 1981;79:305-15. 12. Banm AT. The rationale for esthetic orthodontic treatment in the adult patient. AM J OR'roOD 1975;67:304-15. 13. Gosney MBE. An investigation into factors which may deter patients from undergoing orthodontic treatment. Br J Orthod 1985;12:133-8. 14. Maj G, Squarzoni Grilli AT, Belletti MF. Psychologic appraisal of children facing orthodontic treatment. AM J OR'rrtOD 1967; 53:849-57. 15. Lewis HG, Brown WAB. The attitude of patients to the wearing of a removable orthodontic appliance. Br Dent J 1973;134:8790. 16. Jones ML. An investigation into the initial discomfort caused by placement of an archwire. Eur J Orthod 1984;6:48-54. 17. Oliver RG, Knapman YM. Attitudes to orthodontic treatment. Br J Orthod 1985;12:179-88. 18. Angle EG. Treatment of malocclusion of the teeth: Angle's system. 7th ed. Philadelphia: SS White Dental Manufacturing Co, 1907. 19. Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain 1975;1:277-99. 20. Savedra M, Gibbons P, Tcsler M, Ward J, Wegner C. How do children describe their pain? A tentative assessment. Pain 1982;14:95-104. 21. Kammann R, Flett R. Affectometer 2: a scale to measure current level of general happiness. Aust J Psychol 1983;35:259-65.
356
Brown and Moerenhout
22. Lam T, Kiyak HA, Hohl T, West RA, McNeill RW. Recreational and social activities of orthognathic surgery patients. AM J OarlXOD 1983;83:!43-52. 23. Harris RJ. A primerofmultivariatestatistics. London:Academic Press, 1985:7-9. 24. Terezhalmy GT, Ross GR, Pelleu GB. The language of pain associated with temporomandibular joint myofascial pain dysfunction syndrome. J Dent Res 1981;60:398. 25. Burckhardt CS. The use of the McGill Pain Questionnaire in assessing arthritis pain. Pain 1984;19:305-14.
Am. J. Orthod. Dentofac. Orthop. October 1991
26. Elton D, Stanley G, Burrows G. Psychological control of pain. London: Grune & Stratton, 1983:25-45. Reprint requests to: Dr. David Ferry Brown Department of Psychology University of Wollongong P.O. Box 1144 Wollongong, New South Wales 2500, Australia
BOUND VOLUMES AVAILABLE TO SUBSCRIBERS Bound volumes o f the AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTtIOPEDICS are available to subscribers (only) for the 1991 issues from the Publisher, at a cost o f $48.00 ($62.36 Canada and $59.00 international) for Vol. 99 (January-June) and Vol. I00 (July-December). Shipping charges are included. Each bound volume contains a subject and author index and all advertising is removed. Copies are shipped within 60 days after publication o f the last issue in the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact M o s b y - Y e a r Book, Inc., Circulation Department, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; telephone (800)325-4177, ext. 4351. S u b s c r i p t i o n s m u s t be in force to qualify. B o u n d v o l u m e s a r e not a v a i l a b l e in p l a c e o f a r e g u l a r J o u r n a l s u b s c r i p t i o n .
D u r i n g adolescence a person becomes extremely concerned about physical appearance, especially as it relates to the reaction of significant others, t Physical change, especially change deviating from notions of the ideal, assumes special importance during this period of development. 2 Considering that acceptability of occlusal condition has been shown to be significantly related to acceptability of a general physical appearance, 3 it is no surprise that adolescents form the largest age group seeking treatment to correct a socially unacceptable occlusal condition. Indeed, orthodontists have estimated that 80% of their patients seek their services out of concem for esthetics rather than for health and function. ~ However, patients often feel embarrassed or believe that they are being ridiculed by their peers because of the appearance of orthodontic appliances. 5"6This reaction to some forms of orthodontic therapy assumes special importance for the adoles-
*Department of Psychology, University of V~bllongong, Wollongong, New South Wales, Australia. **Departmentof Orthodontics,Universityof Melbourne. Melbourne, Victoria, Australia. 811124666
cent whose concept of self can be highly susceptible to peer opinions. 7 The peer group often serves as a point of reference and gives the adolescent another evaluation of self. g That there may be a relationship between the age of the patient and undesirable psychological effects of orthodontic treatment was shown in an earlY study b y Haynes. 9"~°Active orthodontic treatment appeai'ed to be discontinued much less frequently in patients 5 to 9 years of age (11.5%) than in patients of i5 years and older (79.9%). This finding caused Haynes to suggest that discontinuance of treatment may be due to essentially psychological and emotional factors. Pain from the appliance and the intrusion of treatment into the patient's daily social life were seen as major causes of discontinuance of treatment. Undesirable psychological effects of therapy do not appear to be a problem in adult orthodontic patients. In a survey of 33 adult patients between 18 and 58 years of age, Tayer and Burek'J found that nearly 74% indicated that they had initial fears concerning peer reaction to their treatment. However, Tayer and Burek concluded that fixed appliance therapy for the adult patient, although initially embarrassing, was soon ac-
349
350
Bro~ivl a n d Moerenhout
cepted and that negative concerns and fears were short lived. Similar findings were reported by Baum. 12 Where the younger patient is concerned, positive -psychological adjustment to treatment does not appear to be quite as apparent as in the adult. More than 50% of 218 patients less than 18 years of age and undergoing active appliance therapy or in full-time retention were reported to have experienced anxiety concerning treatment. ~3Anxiety increased significantly with the age of the patient and was reported more often by girls than by boys. In a study of 50 7- to 14-year-old boys and 50 6- to 14-year-old girls, Maj et al/4 found that 77% of the children reported a high degree of difficulty in psychological adjustment to the treatment. Forty-two percent of the sample reported that the appliance was painful. Distress was especially noted in the older children. However, Lewis and Brown, 15 in a study of 100 British children 9 to 18 years of age, found that only 25% reported that they were anxious about wearing orthodontic appliances. These authors concluded that the level of anxiety induced by appliance therapy was lower than that reported by Maj et al., perhaps because of increasing acceptance by peers. If the age of the patient is a significant factor affecting psychological adjustment to therapy, however, then the difference in the age range between these two studies confounds any direct comparison. While anxiety about wearing an orthodontic appliance may affect a person's psychological adjustment to treatment, the pain experience is also a contributing factor. Most of the discomfort associated with fixed appliances appears to be experienced during the initial 4-week adjustment period or coincides with appliance adjustment." After placement of a fixed appliance, only two of a sample of 30 patients 11 to 30 years of age reported no pain. ~6 There was a decreasing, although uneven, gradient of pain over the 16 days that followed placement of the appliance. During the first 5 days after placement, less discomfort was reported by the under16-year age group that by the over-16-year group. These findings may not be explained by a simple relationship between type of orthodontic appliance used and reported pain. In a study of patients undergoing active orthodontic therapy (69% with fixed appliances, 12.5% with removable appliances, and 18.5% with a combination of the two), there was no significant difference in reported pain intensity between the subjects wearing fixed appliances and those wearing removable appliances. ~7However, 28% reported a wish to discontinue appliance wear because of pain intensity, and 39% reported that the worst thing about appliance wear was the intensity of the pain. These research findings suggest that there may well
Am. J. Orthod. Dentofac. Onhop. October 1991
be a nonlinear relationship between age and psychosocial adjustment to fixed appliance therapy. However, the different age ranges in the various studies reviewed confound any direct comparative conclusions. The aim in the present study is to compare in a systematic manner the psychosocial adjustment of preadolescents, adolescents, and adults to fixed-appliance orthodontic therapy. METHOD
Subjects were patients of l I years or older who were candidates for orthodontic intervention with full fixed appliances. Specialist orthodontists practicing in the greater Melbourne area were asked to approach consecutive patients who were scheduled to undergo treatment within a 6-month period. A total of 76 patients accepted the invitation to participate in the study. Informed consent was obtained from the parents of juvenile patients and directly from the adult patients. PROCEDURE
A longitudinal series of four questionnaires was used for the data collection. Adult subjects and juvenile subjects and their parents were given both a verbal and a written explanation of the research study and instructions for completion of the questionnaire. The subjects were instructed to complete the first questionnaire (time 1) the morning after the separation phase of treatment. This questionnaire also contained a written explanation of the research study and the instructions for completion. The second questionnaire (time 2) was completed on the morning after initial banding. That was when at least one arch wire had been placed in the patients' orthodontic appliance to begin initial tooth movement. The third questionnaire (time 3) was completed on the morning after the first adjustment, and the final questionnaire was completed on the morning after the second adjustment (time 4). In summary, time 1 (TI) refers to 1 day after separation; time 2 (T2) to 1 day after banding, which was 2 to 7 days after separation; time 3 (T3) to 1 day after adjustment, which was 3 to 4 weeks after full fixed appliances had been placed; and time 4 (T4) to 1 day after adjustment, which was 3 to 4 months after banding was completed. Each participating orthodontist was asked to complete a 16-part treatment modality inventory for each of his or her patients volunteering to participate in the study. Information was collected on whether single or both arches ~ere receiving treatment, the type of initial arch wire (Multiflex, 0.012-inch stainless steel, 0.014inch stainless steel, nitinol, other), the type of appliance used (Begg, edgewise, other), whether extractions had been required, ratio of bonds to bands, the type (mod-
Volume 100 Number 4
ules, brass ligature, other), and the time of separation before banding. Information was also collected on any medication prescribed before placement of bands. Patients' dental malocclusion was recorded according to Angle's classification. ~s Demographic data on each patient were collected by means of the questionnaire at time 1 only. Subjects were instructed to complete the questionnaire on the morning after each ph.ase of treatment. The adult subjects and both the subjects and their parents in the case of the preadolescent and adolescent samples were instructed in completion of the questionnaires. The parents were instructed to assist the subjects in the completion of the questionnaire only if necessary. Included in each questionnaire was a version of the McGill Pain Questionnaire (MPQ). 19 The MPQ is a rating scale that measures intensity and quality of pain and has been shown to have high reliability and construct validity. Patients are asked to select, among 20 sets of pain descriptors, the words that best describe their pain experience at the present time. The pain descriptors in each set have been scaled from least to greatest pain intensity. This scale has been shown to be reliable when self-administered, as in the case of adults, or when administered by a second party, as in the case of parent to child. A subject's score is derived from the number of words chosen and the rank order of those words and is expressed as the total pain-rating index (PRI). The adjectives used as pain descriptors have been demonstrated to be suitable for children from 9 years of age on. 2° Children as young as 9 to 12 years were able to select a variety of pain descriptors from a given list, and no appreciable difference within this age range was found. 2° Further data were collected regarding any medication taken and location of the pain experience. The subject's psychological well-being was measured by a 20-item scale devised by Kammann and Flett. 2~ This scale is a measure of a person's current level of general happiness or sense of well-being and is negatively correlated with somatic complaints. A subject's well-being score is a summation of his or her responses to 20 adjectives describing psychological mood states. Subjects report how they feel at the present time by responding on a five-point scale from "not at all" to "all the time" to the adjectives describing their mood state. This scale has been reported to have high internal reliability (ct = 0.88) and construct validity. 2~ Changes in a subject's engagement in recreational and social activities were measured by a modification of an index developed for subjects undergoing orthognathic surgery. 22 This index comprised eight recreational activities (e.g., swimming, jogging, golf) and
Pain experience and psychological adjustment to treatment
351
eight social activities (e.g., working on hobbies, going to parties, visiting friends). The items covered activities commonly engaged in by the age groups sampled. The frequency of activities was measured in terms of "no participation" to "regular participation." A subject's activity score was a summation of the frequency of these activities over the past few weeks. RESULTS
Of the total sample, 79% (n = 60) completed all questionnaires. The subjects were classified into the following age groups: (1) a preadolescent group 11 to 13 years of age (n = 23); (2) an adolescent group, 14 to 17 years (n = 25); and (3) an adult group, 18 years and over (n = 12). The percentage breakdown of the sample (group 1, 38%; group 2, 42%; and group 3, 20%) was considered to be a fair reflection of the age ratio of patients normally seeking orthodontic treatment. Forty percent of the patients were men or boys, and 60% were girls or women. The internal reliability of the psychometric scales, as assessed by Cronbach's alpha, was never less than 0.85 for the pain scale and 0.74 for psychological wellbeing. Before differences between age groups could be tested, it was considered necessary to determine whether any significant relationships existed between certain confounding factors and the response variables of pain, psychological well-being, and recreational/social activities. Differences between various factors and the dependent variables over the time periods sampled were evaluated by repeated-measures analysis of variance. No significant differences were found for any of the response variables between male and female subjects, between the treatment mechanics groups, or between Angle classification groups at any of the time periods sampled. Differences between the age groups over the time periods sampled for the response variables of pain, psychological well-being, and recreational/social activities (Table I) were tested by profile analysis. -'3 Profile analysis tests whether the three age groups have identical patterns of highs and lows for the response variable over the phases of treatment. If there is no interaction between age group and phase of treatment for the response variable tested, the hypothesis of parallel profiles is accepted. The level of statistical significance was set at p --< 0.05. For each response variable, the profile of the preadolescents was first compared with that of the adults, and then the profile of these subjects was compared with the adolescent profile. This independent set of comparisons tests the hypothesis that orthodontic treht-
352
Brown attd Moerenhout
Am. J. Orthod.Dentofac.Orthop. October1991
Table I. Group means and standard errors for each response variable over the time periods sampled
After separation Mean Pain (PRI) Group I Group 2 Group 3 Psychological Well-b6ing Group 1 Group 2 Group 3 Recreational Activities Group I Group 2 Group 3 Social Activities Group 1 Group 2 Group 3
I
After banding
SE
Mean
8.87 15.44 9.97
2.09 2.77 2.27
1.71 1.30 1.63
I
First adjustment
SE
Mean
11.74 22.06 10.29
2.31 3.07 2.07
0.20 0.23 0.26
1.53 1.18 1.65
1.36 1.40 0.88
0.09 0.09 0.12
1.48 1.72 1.52
0.07 0.07 0.12
SE
Mean
8.61 11.32 10.08
1.77 2.42 1.82
7.72 ! 3.52 10.33
1.69 2.16 2.32
0.26 0.24 0.32
1.51 1.59 1.40
0.25 0.22 0.33
1.83 1.23 1.52
0.19 0.20 0.32
1.41 1.29 0.98
0.09 0.09 0.16
1.42 1.44 0.96
0.09 0.07 0.14
1.39 1.37 0.89
0.07 0.08 0.12
1.60 1.56 1.53
0.08 0.09 0.14
i.60 1.67 1.40
0.09 0.09 0.16
1.51 1.67 1.35
0.07 0.08 0.15
ment may be more traumatic for adolescents than for preadolescents and for adults. No significant difference was found between the pain profiles of the preadolescent and adult subjects. However, a significant difference (F = 3.54; df = 3,55; p = 0.02) was found when the pain profile of the adolescents was compared with the profiles of the preadolescent and adult subjects. The profile analysis indicated that there was an interaction between age group and reported pain over the phases of treatment. The level of the pain profile for the adolescents was significantly (F = 10.69; df = 1,57; p = 0.002) laigher after the banding phase when compared with the pain responses of the preadolescent and adult subjects. Further, X2 analyses indicated no significant association between the reported use of analgesics and age groups over the time periods sampled, suggesting that the difference in reported pain between the groups may not be simply a reflection of different usage of analgesics. No significant difference was found between the well-being profiles of the preadolescent and adult subjects. The well-being profile of the adolescents did sign!ficantly differ (F = 2.71; df = 3,55; p = 0.05) from the profiles of the preadolescent and adult subjects. The profile analysis indicatedan interaction between age groups and psychological well-being over the phases of treatment. The level of psychological wellbeing for the adolescents was significantly (F = 7.63; df = 1,57; p = 0.008) lower after the banding phase than the level of well-being observed in the preadolescent and adult subjects. Similar to the pain data, these
I
Second adjustment I
SE
results suggest an interaction between age group and psychological well-being over the phases of treatment and a difference in the adolescents' level of responses compared with those of the preadolescent and adult subjects. A small decrease in social and recreational activity between TI and T2 was seen in the adolescent group as compared with the preadolescents and adults, but this was not significant. The frequency of use for each of the 20 sets of pain descriptors was examined for each age group at the postseparation and postbanding phases of treatment. While the total pain score (PRI) on the MPQ is an indication of quantitative differences in reported pain, differences in the use of pain-descriptor sets indicates differences in the quality of the pain experience. Following the criterion set by Terezhalmy et al.,-'~4 the sig nificant frequency of use for each set of pain descriptors was set at greater than 50% of usage for each age group. With the use of this criterion, a profile description of the quality of the pain experienced by each age group can be made at the postseparation and postbanding phases. At the postseparation phase (Fig. 3), both the preadolescent and adult groups had a 9, 16 set profile, and the adolescent group had a 5, 9, 16, 18 profile. At the postbanding phase (Fig. 4), the preadolescent group had a 5, 9, 10, 16, 18 profile, the adult group showed a similar profile with the exclusion of set 18, and the adolescent group had a 4, 5, 6, 9, 10, 16, 17, 18, 20 profile. These subclasses of pain descriptors covered the
Volume I00
Pain experience and psychological adjustment to treatment
353
Number 4
23.00
-
22.00
2.00
--
/
20.00
18.00
:o
-
16.oo=
i
= 14,00
-1.00
--
12.00
10.00 8.00
X
I1 - 13year$ old
|
14 - 17 years old
$
18+ years old
6.00
I
I
TI
T2
I
"'/
"f/I TI
I
T3
I T2
I T3
//
T4 Phase o [ T r e a l m e n t
Phase of T r e a t m e n t
WELL-BEING
PAIN
Fig. 2. Mean psychological Well-being for each age group across phases of treatment.
Fig. 1. Mean pain level for each age group across phases of treatment.
*
90
II • 13 years old
o
14 - 17 years old
•
18 ÷ years old
o o
70
i o
~
6o 50
•
~ ~-.~
o 40
/,,
}
20
I 1
I T4
I 2
I 3
I 4
I 5
6
7
8
Subclasses
• = ~ 9 10 11 12 13 14 15 16 17 18
---I 20
of Paln Dcscr|ptors
TREATMENT
I'tlASE 1
Fig, 3. Percentage of each age group using subclasses of pain descriptors the day following the separation (T1) phase of treatment. Subclasses: 1, flickering-pounding; 2, jumping-shooting; 3, prickinglancinating; 4, sharp-lacerating; 5, pinching-crushing; 6, tugging-wrenching; 7, hot-searing; 8, tinglingstinging; 9, dull-heavy; 10, tender-splitting; 11, tiring-exhausting; 12, sickening-suffocating; 13, fearfulterrifying; 14, punishing-killing; 15, wretched-blinding; 16, annoying-unbearable; 17, spreading-piercing; 18, tight-tearing; 19, cool-freezing; 20, nagging-torturing.
354 Brown and Moerenhout
Am. J. Orthod. Dentofac. Orthop. October 1991 ,
11 - 13 ~ e a r s o l d
o
14 - 17 y e a r s o l d
•
IS + ~¢ars o l d
1°° T 9O
i
o
70
~
60
)
50
~g.
40 30 20
0
2
3
4
5
6
7
8
9
10 11 12 13 '/4
5 16 17 18 19 20
Subclasses of Pain Descriptors TREATMENT PHASE 2
Fig. 4. Percentage of each age group using subclasses of pain descriptors the day following the banding (1"2) phase of treatment. Subclasses: I, flickering-pounding; 2. jumping-shooting; 3, pricking/ancinating; 4, sharp-lacerating; 5, pinching-crushing; 6, tugging-wrenching; 7, hot-searing; 8, tinglingstinging; 9, dull-heavy; 10, tender-splitting; 11, tiring-exhausting; 12, sickening-suffocating; 13, fearfulterrifying; 14, punishing-killing; 15, wretched-blinding; 16, annoying-unbearable; 17, spreading-piercing; 18, tight-tearing; 19, cool-freezing; 20, nagging-torturing.
sensory (subclasses 1 to 10), evaluative (subclass 16), and miscellaneous (subclasses 17 to 20) dimensions of the pain experience defined by Melzack. 19 It is interesting to note that the affective dimension (subclasses 11 to 15) of the pain experience was not prominent in any of the profiles. All age groups tended to select pain descriptors from the sensory dimension. However, the adolescent group tended to use a greater number of sets from this dimension than did the other age groups; this is especially evident after the separation phase of treatment. DISCUSSION
The results indicate that the adolescents generally reported a higher level of pain (PRI) after all phases of treatment (Fig. 1). This difference is clearly noted after the banding phase. These pain indices were taken the day after the appliance-adjustment phases, which have been suggested as being associated with most discomfort after treatment." All groups reported some level of pain after the treatment-adjustment phases. After the banding phase, however, only the adolescents showed a higher level of pain intensity than that reported by Melzack 19for dental pain (mean pain level, 19.5). Fur-
thermore after the separation and banding phases of treatment, the adolescents showed greater use of descriptors from the sensory dimension in describing their pain. This is not surprising, considering the high correlation (r = 0.89) reported by Melzack between the number of descriptors chosen and the PRI score. The descriptor profiles are similar to other findings, suggesting that patients with acute pain tend to use more descriptors from the sensory dimension and fewer from the affective dimension than do patients with chronic pain. 2~ This was to be expected in view of the fact that the present pain measurements reflect the patient's reaction the day after the banding-adjustment phase of treatment and may not reflect a chronic pain condition. The higher level of pain (PRI) reported by the adolescent group did not appear to be due to a difference in treatment characteristics or to differences in the use of analgesics. It is possible, however, that levels of reported pain are confounded with, or mask, other affective reactions to treatment. Reported pain can often be a somatization of either anxiety or depression. 16 In this situation, reported pain may be the patient's attempt to translate feelings of anxiety or depression into a tangible physiologic problem.
Voh,me tO0
Number 4
The preadolescents and the adults showed a similar profile for psychological well-being over the phases o f treatment. Compared with the other age groups, the adolescent profile was characterized by lower wellbeing after the banding phase (Fig. 2). In view o f the high negative correlation ( - 0.84) reported between the well-being scale used in the present study and the Beck Depression Scale, low levels o f psychological wellbeing may well reflect a greater degree o f depression. 2~ These differences in psychological adjustment are consistent with the higher pain levels reported by the adolescents during the phases of treatment. The lower level o f well-being seen in the adolescent group at the 4-month treatment phase tends to suggest that this group may have long-term difficulty in adjustment. Although it is important to note that the mean well-being scores generally apepar within levels given for a normal adult population (mean = 1.43, SD = 1.08), the group scores do indicate relative differences in psychological adjustment to treatment. The poorer adjustment to treatment shown by the adolescent group m a y be due to their stage o f psychological development. Adolescents may seek orthodontic treatment out o f concern for their physical appearance. 3 However, the form o f treatment mechanics used in fixed-appliance orthodontic therapy has been shown to cause patients some concern. T M The higher levels o f pain and the lower levels o f psychological well-being reported by the adolescent group may suggest a more traumatic reaction to treatment than seen in the other age groups. It can be suggested that, perhaps because o f their critical period o f psychological development, adolescents find it more difficult to adjust to the initial effects o f fixed-appliance orthodontic therapy. Although the degree of this reaction to treatment does not warrant undue alarm, the results do suggest that further research is needed to examine whether psychological preparation, in the form o f brief counseling, may be o f benefit to some adolescent patients about to undergo fixed-appliance therapy. Although systematic changes were found between the pain and well-being profiles o f the age groups sampled, this study has certain limitations on the interpretation o f results. It may well be that the similarity in the profiles o f the preadolescents and adults is due to some parents assisting their children in the completion of the questionnaires. In this situation, the parents may project their own concerns regarding the immediate psychological effects o f treatment. If this had happened, then the indices for the preadolescents may have been confounded with adult responses. In this situation, however, greater heterogeneity than that observed might have been expected for the response measures within
Pah~ experience and psychological adjustment to treatment
355
the preadolescent group. It must also be noted that the pain descriptor profiles are based on previous research suggesting a cut-off point o f more than 50% o f subjects choosing a given word. These profiles may well change substantially, given a different cut-off criterion.
REFERENCES
1. Tierno MJ, Arts D. Responding to self-concept disturbance among early adolescents: a psychological view for educators. Adolescence 1983;18:577-84. 2. Schonfield WA. Inadequate masculine physique as a factor in personality development of adolescent boys. Psychosom Med 1950;12:49-54. 3. Brown DF, Spencer AJ, Tolliday PD. Social and psychological factors associated with adolescents' self-acceptance of occlusal condition. Community Dent Oral Epidemiol 1987;15:70-3. 4. Rosenberg M. Malocclusion and cranio-facial malformations: self-concept implications. Paper presented at the Workshop on Psychological Aspects of Craniofacial Malformation. Hilton Head, S.C., October 1974. 5. BreeceGL, Nieberg LG. Motivations for adult orthodontic treatment. J Clin Orthod 1986;10:166-71. 6. ShawWC, Meek SC, Jones DS. Nicknames, teasing, harassment and the salience of dental features among school children. Br J Orthod 1980;7:75-80. 7. Coleman E. Counselling adolescent males. Am Personnel Guidance J 1981;60:215-9. 8. Steinberg L, Silverberg SB. The vicissitudes of autonomy in early adolescence. Child Dev 1986;57:841-51. 9. Haynes S. Discontinuation of orthodontic treatment relative to patient age. J Dent 1974;2:138-42. 10. Haynes S. Discontinuation of orthodontic treatment in the General Dental Service in England and Wales, 1972-1979. Br Dent J 1982;152:127-9.
! 1. Tayer Btl, Burek MJ. A survey of adults' attitudes toward orthodontic therapy. AM J OR'roOD 1981;79:305-15. 12. Banm AT. The rationale for esthetic orthodontic treatment in the adult patient. AM J OR'roOD 1975;67:304-15. 13. Gosney MBE. An investigation into factors which may deter patients from undergoing orthodontic treatment. Br J Orthod 1985;12:133-8. 14. Maj G, Squarzoni Grilli AT, Belletti MF. Psychologic appraisal of children facing orthodontic treatment. AM J OR'rrtOD 1967; 53:849-57. 15. Lewis HG, Brown WAB. The attitude of patients to the wearing of a removable orthodontic appliance. Br Dent J 1973;134:8790. 16. Jones ML. An investigation into the initial discomfort caused by placement of an archwire. Eur J Orthod 1984;6:48-54. 17. Oliver RG, Knapman YM. Attitudes to orthodontic treatment. Br J Orthod 1985;12:179-88. 18. Angle EG. Treatment of malocclusion of the teeth: Angle's system. 7th ed. Philadelphia: SS White Dental Manufacturing Co, 1907. 19. Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain 1975;1:277-99. 20. Savedra M, Gibbons P, Tcsler M, Ward J, Wegner C. How do children describe their pain? A tentative assessment. Pain 1982;14:95-104. 21. Kammann R, Flett R. Affectometer 2: a scale to measure current level of general happiness. Aust J Psychol 1983;35:259-65.
356
Brown and Moerenhout
22. Lam T, Kiyak HA, Hohl T, West RA, McNeill RW. Recreational and social activities of orthognathic surgery patients. AM J OarlXOD 1983;83:!43-52. 23. Harris RJ. A primerofmultivariatestatistics. London:Academic Press, 1985:7-9. 24. Terezhalmy GT, Ross GR, Pelleu GB. The language of pain associated with temporomandibular joint myofascial pain dysfunction syndrome. J Dent Res 1981;60:398. 25. Burckhardt CS. The use of the McGill Pain Questionnaire in assessing arthritis pain. Pain 1984;19:305-14.
Am. J. Orthod. Dentofac. Orthop. October 1991
26. Elton D, Stanley G, Burrows G. Psychological control of pain. London: Grune & Stratton, 1983:25-45. Reprint requests to: Dr. David Ferry Brown Department of Psychology University of Wollongong P.O. Box 1144 Wollongong, New South Wales 2500, Australia
BOUND VOLUMES AVAILABLE TO SUBSCRIBERS Bound volumes o f the AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTtIOPEDICS are available to subscribers (only) for the 1991 issues from the Publisher, at a cost o f $48.00 ($62.36 Canada and $59.00 international) for Vol. 99 (January-June) and Vol. I00 (July-December). Shipping charges are included. Each bound volume contains a subject and author index and all advertising is removed. Copies are shipped within 60 days after publication o f the last issue in the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact M o s b y - Y e a r Book, Inc., Circulation Department, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; telephone (800)325-4177, ext. 4351. S u b s c r i p t i o n s m u s t be in force to qualify. B o u n d v o l u m e s a r e not a v a i l a b l e in p l a c e o f a r e g u l a r J o u r n a l s u b s c r i p t i o n .
