How is orthodontic treatment need associated with perceived esthetic impact of malocclusion in adolescents?

Introduction

The purpose of this research was to evaluate the esthetic impact of orthodontic treatment need in adolescents.

Methods

This cross-sectional study was performed with 1172 adolescents aged 12 (n = 638) years and 15 (n = 534) years from Salvador, Bahia, Brazil. The esthetic impact was the following outcome variables: Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale. The normative orthodontic treatment need was assessed by the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) and by the Dental Aesthetic Index (DAI). Logistic regression models were adjusted, estimating crude odds ratio with the respective 95% confidence intervals. The variables with P ≤0.20 in the individual analyses were tested in multiple logistic regression models, remaining the variables with P ≤0.05.

Results

The results showed a statistically significant association for the esthetic impact (Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale) when assessing the normative orthodontic treatment need by the DAI ( P <0.05). However, there was no significant association between subjective esthetic impact and normative needs when using the IOTN-DHC ( P >0.05).

Conclusions

DAI was more associated with the adolescents’ esthetic concern than IOTN-DHC and should be the Index of Orthodontic Treatment Need to be selected to complement the patient’s self-perception.

Highlights

  • Normative orthodontic treatment need was assessed by the Dental Health Component of the Index of Orthodontic Treatment Need and by the Dental Aesthetic Index.

  • The subjects were adolescents (n = 1172), aged either 12 or 15 years.

  • Dental Aesthetic Index was better associated with adolescents’ esthetic concerns than Dental Health Component of the Index of Orthodontic Treatment Need.

Orthodontic treatment need is traditionally measured by normative epidemiologic indexes. The most commonly used indexes are the Dental Aesthetic Index (DAI), , recommended by the World Health Organization, and the Index of Orthodontic Treatment Need (IOTN). Because of their clinical features, the normative indexes might not reflect the actual expectation of patients , who seek orthodontic treatment when their quality of life is affected or when there is an impact on dental esthetics. ,

Patients’ self-perception has been studied to understand patients who are mostly affected by malocclusions in order to complement the clinical orthodontic diagnosis. Studies using self-perception indicators such as the Aesthetic Component of the Index of Orthodontic Treatment Need (IOTN-AC) , , and the Oral Aesthetic Subjective Impact Scale (OASIS) , , , , , are not yet unanimous regarding the relationship between clinical diagnosis and individual perception. Some authors affirm that the normative criteria overestimate individual perception, , and others , , , believe there is no difference in the assessment of orthodontic treatment need.

The clinical assessment of malocclusion is essential to the orthodontist, but self-perceived dental attractiveness and the subjective perception about malocclusion are the primary factors contributing to self-concept in adolescents. , The lack of evidence regarding the normative and subjective esthetic evaluation can be explained by the absence of studies evaluating the main orthodontic treatment need indexes exclusively. There are no reports about the strength of association of the most used normative (DAI and Dental Health Component of the Index of Orthodontic Treatment Need [IOTN-DHC]) and perceived (IOTN-AC and OASIS) epidemiologic instruments in the same evaluation.

Thus, this evaluation aimed to answer the following question: how is orthodontic treatment need associated with adolescents’ perceived esthetic impact of malocclusion? We hypothesized that, because the DAI is an esthetic index, it will have a stronger association with the perceived esthetic impact of malocclusion than the IOTN-DHC.

Material and methods

Subjects and study design

Approval from the Research Ethics Committee in Brazil was granted for the protocol and informed consent process of this study (no. 58301416.4.0000.5385).

This cross-sectional study included adolescents aged 12 years and 15 years from Salvador, Bahia, Brazil. The sample size was calculated, considering a 5% significance level, 90% test power, and 1.5 effect size, obtaining a minimum of 1054 patients. Probabilistic sampling was performed by conglomerates. The distribution of 12- and 15-year-old adolescents in each administrative district of Salvador was determined from information provided by the Municipal Secretary of Education. The sample was stratified according to the administrative district, and in the first phase, schools were selected using a simple randomization procedure. Similarly, in the second phase, adolescents were selected for the sample using a simple randomization procedure. The eligibility criteria were adolescents without current or previous orthodontic treatment and without physical or intellectual limitations that would prevent them from undergoing the examination. Adolescents with physical limitations, cleft lip, and palate, or any form of congenital craniofacial deformities were excluded from the study. Moreover, the sample was increased by 10% to compensate for possible dropouts, leading to a total of 1172 adolescents aged 12 years (n = 638) and 15 (n = 534) years.

A structured questionnaire was used to collect data on sex and age. The self-perception of orthodontic treatment need was determined by the IOTN-AC and by the OASIS. ,

The IOTN-AC was used to assess the self-perception of orthodontic treatment need using a dental attractiveness scale illustrated by 10 colored photographs presenting a decreasing and continuous attractiveness level, in which image 1 represented the most attractive dental arrangement and image 10 was the least attractive. The adolescents themselves performed the assessments, identifying the level of esthetic compromise in the scale images considered similar to their own smile. Images 1 to 4 were related to patients with no or little orthodontic treatment need (grades 1 and 2); images 5, 6, and 7 showed moderate orthodontic treatment need (grade 3); and images 8, 9, and 10 showed severe orthodontic treatment need (grades 4 and 5).

To assess the perceived esthetic impact of malocclusion, the OASIS was used. The OASIS includes 5 questions with 5 answer options on a 7-point Likert scale, and a higher OASIS score indicates a higher esthetic concern. , The results of the OASIS were completed with the perceived need for orthodontic treatment scored by the adolescents using the IOTN-AC. ,

The normative orthodontic treatment need was determined by the IOTN-DHC and by the DAI. The data were collected through clinical examination performed in the school environment, under natural light, using a World Health Organization probe. The researcher was calibrated, obtaining a weighted kappa higher than 0.97 for both normative indexes (IOTN-DHC and DAI).

The IOTN-DHC classifies malocclusions according to the severity of the occlusal characteristics in 5 grades: grades 1 and 2 represent no or little need, grade 3 shows moderate need, and grades 4 and 5 show a definite treatment need. The IOTN-DHC was dichotomized into no treatment need (IOTN grades 1 and 2) and treatment need (grades 3, 4, and 5). The DAI classifies malocclusion in 4 categories based on severity and treatment need: no malocclusion or mild change/no treatment need (DAI 1, 25), established malocclusion and/or optional treatment need (DAI 2, 26-30), severe malocclusion and/or highly desirable treatment need (DAI 3, 31-35), and debilitating malocclusion and/or mandatory treatment need (DAI 4, 36). The DAI was dichotomized into DAI 1 for no orthodontic treatment need and DAI higher or equal to 2 for orthodontic treatment need.

Statistical analysis

The self-perception of orthodontic treatment need was considered the outcome variable and dichotomized as without esthetic impact or with esthetic impact. To meet the analysis proposal, IOTN-AC was dichotomized as without esthetic impact (low self-perception of orthodontic treatment need; grades 1 and 2) or with esthetic impact (high self-perception of orthodontic treatment need; grades 3, 4 and 5). OASIS was dichotomized by the median of the scores as without esthetic impact (≤14) or with esthetic impact (>14). Dichotomization was used to discriminate adolescents who reported esthetic perception of malocclusion from adolescents who did not report such perceptions.

Descriptive analyses were performed, considering the outcome (IOTN-AC and OASIS) for the explanatory (independent) variables (IOTN-DHC and DAI, age, and gender). Multiple logistic regression was performed to detect possible associations between the independent variables and the self-perception of orthodontic treatment need (outcome). The crude odds ratios were estimated from the coefficients of the individual models of each variable, with their respective 95% confidence interval (CI). The variables with P ≤0.20 in the individual analyses were tested in multiple logistic regression models, maintained the variables with P ≤0.05. Then, the adjusted odds ratios were estimated in the multiple models. All analyses were performed using the SAS (SAS Institute Inc, Cary, NC, 2010) and R (R Foundation for Statistical Computing, Vienna, Austria) programs.

Results

Table I presents the data for perceived esthetic impact according to the IOTN-AC associated with the orthodontic treatment need, according to the IOTN-DHC. There was no association between the IOTN-AC and IOTN-DHC ( P >0.05). Table II shows the association of IOTN-AC with the orthodontic treatment need, diagnosed by the DAI. Adolescents with orthodontic treatment need according to the DAI were 2.62 (95% CI, 1.77-3.89) times more likely to perceive the esthetic impact assessed by the IOTN-AC ( P <0.05). In both cases, the perceived esthetic impact (IOTN-AC) was adjusted in the model for the age of 12 years.

Table I
Association between IOTN-AC and IOTN-DHC
Variables Categories n (%) IOTN-AC Crude OR (95% CI) P value Adjusted OR (95% CI) P value
Without esthetic impact With esthetic impact
Age 12 y 638 (54.4) 551 (86.4) 87 (13.6) 2.32 (1.53-3.51) <0.0001 2.32 (1.53-3.51) <0.0001
15 y 534 (45.6) 500 (93.6) 34 (6.4) Ref Ref
Gender Male 484 (41.3) 436 (90.1) 48 (9.9) Ref
Female 688 (58.7) 615 (89.4) 73 (10.6) 1.08 (0.73-1.58) 0.6993
IOTN-DHC No treatment need 256 (21.8) 236 (92.2) 20 (7.8) Ref
With treatment need 916 (78.2) 815 (89.0) 101 (11.0) 1.46 (0.89-2.41) 0.1004

OR, odds ratio; CI, confidence interval; Ref , Reference level of independent variables.

Reference level of outcome.

Table II
Association between IOTN-AC and DAI
Variables Categories n (%) IOTN-AC Crude OR (95% CI) P value Adjusted OR (95% CI) P value
Without esthetic impact With esthetic impact
Age 12 y 638 (54.4) 551 (86.4) 87 (13.6) 2.32 (1.53-3.51) <0.0001 2.12 (1.40-3.23) 0.0016
15 y 534 (45.6) 500 (93.6) 34 (6.4) Ref Ref
Gender Male 484 (41.3) 436 (90.1) 48 (9.9) Ref
Female 688 (58.7) 615 (89.4) 73 (10.6) 1.08 (0.73-1.58) 0.6993
DAI No treatment need 691 (59.0) 647 (93.6) 44 (6.4) Ref Ref
With treatment need 481 (41.0) 404 (84.0) 77 (16.0) 2.80 (1.90-4.14) <0.0001 2.62 (1.77-3.89) <0.0001
Only gold members can continue reading. Log In or Register to continue

Stay updated, free dental videos. Join our Telegram channel

Jan 9, 2021 | Posted by in Orthodontics | Comments Off on How is orthodontic treatment need associated with perceived esthetic impact of malocclusion in adolescents?

VIDEdental - Online dental courses

Get VIDEdental app for watching clinical videos