Keywords
malocclusion - perceptions - oral health-related quality of life - Dental Aesthetic
Index - Index of Orthodontic Treatment Need
Introduction
An individual's personality is significantly shaped by how they perceive their appearance,
and when they present with malocclusion, especially anteriorly, negative social responses
are triggered which can lead to a poor self-image.[1]
[2] In fact, malocclusion could even be considered a physical disability as it restricts
a person's social relationships, and hence their opportunities.[3] As people inherently feel the need to belong and be accepted by their social network,
they are likely to be considerably affected if they do not meet the socially acceptable
appearance norms.[4] Even small deviations from the commonly held standards of appearance can influence
young adults in particular, leading to reduced self-esteem and a belief that they
are inferior to their peers.[1] Such a lack of self-confidence is also a critical issue in that it often affects
an individuals' quality of life (QoL) and prevents them from developing an effective
professional profile.[5]
The field of orthodontics tends to be subject to limited funding, and thus it must
often prioritize those patients with the greatest need for treatment. To this end,
sociodental indicators offer a way to determine the needs of individual patients.[3]
[6] In addition, orthodontic patients who do not need immediate treatment can avoid
the potential risks posed by unnecessary treatment by assessing their behavior and/or
motivation before the start of treatment.[3]
[6] For example, there is thus far a lack of evidence indicating that patients with
minor malocclusions would obtain significant benefit from orthodontic treatment in
terms of their dental function and oral health.[7]
Nevertheless, patients may request orthodontic treatment out of concern for their
appearance. In standard practice, assessing the need for orthodontic treatment is
generally based on several psychosocial factors as well as normative assessments through
the use of occlusal indices.[6] However, these methods are solely based on the perspective of the dental clinician,
bypassing the concerns of the patients themselves. Due to this gap between the perceptions
of what constitutes an acceptable dental appearance and whether orthodontic intervention
is required, traditional assessment methods have proven to be inadequate.[8]
[9]
[10]
For example the Dental Aesthetic Index (DAI) and Index of Orthodontic Treatment Need
(IOTN), which are considered conventional occlusal indices, can be used to assess
a malocclusion in terms of its aesthetic and anatomic characteristics. However, they
do not reflect how the malocclusion is causing a degraded self-image that is impacting
the patient's QoL regarding their well-being and daily functioning.[11]
Previous research has indicated that a patient's psychosocial well-being is strongly
related to how they perceive their dental aesthetic appearance. As psychosocial well-being
informs the patient's general health, problems with dental aesthetics, as perceived
by the patient, are an important factor, particularly as they predict a worsening
QoL in terms of oral health.[1]
[12] As a result, research attention has recently focused on the development of appropriate
psychometric tools to specifically measure a patient's oral health-related QoL (OHQoL).
One such tool, namely the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ),
was developed to measure to what extent the self-image of young adult orthodontic
patients is affected by their dental aesthetic appearance.[13] The PIDAQ has been shown to have good reliability and construct validity for adults
in international contexts concerning the association between psychosocial dimensions
and dental aesthetics (as perceived by the patient).[14]
[15]
[16]
[17]
[18] However, the literature revealed a limited number of studies that have explored
the impact of malocclusion on the psychosocial well-being of the affected individuals
and results are conflicted. In addition, how clinician-rated and self-rated malocclusion
levels differ in their impact is also unclear and should be further explored.
Thus, the aim of this study was to investigate the psychosocial impact of different
grades of malocclusion and self-rated orthodontic treatment need on a sample of young
adult dental patients attending a tertiary dental care facility in the Western Province
of Saudi Arabia.
Materials and Methods
This was a cross-sectional study at a public tertiary dental care facility in the
city of Al-Madinah Al-Munawwarah, Saudi Arabia. Data collection was conducted over
a period of 3 months (May 2021–July 2021) through a convenience sampling method. Ethical
approval was granted by Taibah University, College of Dentistry Research and Ethics
Committee (TUCDREC/04032021).
Study Sample
The sample included eligible young adult dental patients 18 to 30 years old who were
attending a dental screening appointment for further dental treatment and were able
to read and speak Arabic. Patients who studied/studying dentistry and those with a
history of orthodontic treatment and/or patients undergoing current orthodontic treatment
as well as patients with craniofacial deformity were excluded from the study.
Sample size calculation was performed using Epi Info Software v5.5.6 (U.S. Department
of Health and Human Services, Centers for Disease Control and Prevention, United States).
The calculation was based on a total population of 660 patients who visited the Dental
Hospital for their initial screening appointment during the study period (3 months)
and were eligible for inclusion in this study. Expected frequency was set at 17.8%
(frequency of moderate and severe malocclusion) and an acceptable margin of error
of 5%. A sample of 350 provided power of the study above 99.9%.
Research Instruments
Patients attending their first visit screening appointment were consecutively recruited
and introduced to the study. These screening appointments are usually conducted by
dental interns every day of the week during the morning clinical session. If they
agree to take part in the study, they were asked to sign a consent form. They were
then asked to complete the PIDAQ (Arabic language version), in addition to a brief
questionnaire that gathered their demographic details. The PIDAQ instrument comprised
23 items categorized into four sections, namely dental self-confidence (DSC; 6 items),
social impact (SI; 8 items), psychological impact (PI; 6 items), and aesthetic concerns
(AC; 3 items). The patients self-rated their responses on a 5-point Likert scale (0=not
at all, 1=a little, 2=somewhat, 3=strongly, 4=very strongly). Each subscale score
can be calculated separately and is obtained by summing the item scores. It is important
to note that unlike the rest of the PIDAQ domains, the DSC domain has a positive meaning
(i.e., the higher the score the less the impact), and hence, when calculating the
total PIDAQ score, the scores of the DSC domain were inverted.[13] A recent study has adapted, psychometrically tested, and validated the PIDAQ's Arabic
language version.[16]
After completing the questionnaire, the participants were asked to rate their malocclusion
level using the IOTN-AC. This instrument involved presenting 10 images depicting malocclusions
of the anterior teeth to patients and asking them to rank these according to how well
they match their own dental appearance on a scale of grade 1 (the best) to grade 10
(the worst).[19] Subsequently, the patient is categorized into one of three groups according to their
IOTN grading: AC grades 1–4 require no orthodontic treatment, AC grades 5–7 have a
moderate or borderline treatment need, and AC grades 8–10 have an immediate treatment
need. In the current study, the participants were also rated by the clinician using
the IOTN-AC grading index.
Finally, the clinician graded the malocclusion level of each participant using the
DAI. This index utilized 10 dentofacial anomaly parameters that assess the anterior
teeth regarding their clinical and aesthetic features. The DAI consists of 10 occlusal
traits related to dentofacial anomalies according to the three components of dentition,
spacing–crowding, and occlusion. Scores for each component were multiplied by a previously
reported weight and a constant was added to obtain a final DAI score for each participant.[20] Malocclusions were categorized into four grades regarding the recommendations for
orthodontic treatment and prioritization: grade 1 is a normal/minor malocclusion with
an absent or slight treatment need (DAI ≤ 25); grade 2 is a definite malocclusion
with a treatment need that is elective (26 ≤ DAI ≤ 30); grade 3 is a severe malocclusion
with a high treatment need (31 ≤ DAI ≤ 35); and grade 4 is a very severe malocclusion
with a compulsory treatment need (DAI ≥ 36).
The clinical examinations in this study were performed by the same orthodontist, who
received training and calibration in the use of the IOTN-AC and the DAI score dental
parameters. The calibration process was conducted before the study to guarantee reliable
data collection. Ten patients were examined twice, 1 week apart, by the same experienced
orthodontist to calculate the intra-examiner reliability. The results showed high
reproducibility with an intraclass correlation coefficient 0.90 for the IOTN-AC and
0.85 for the DAI.
Statistical Analysis
Descriptive statistics (means, standard deviation [SD], frequencies and percentages)
was used to describe the sample's sociodemographic characteristics, malocclusion levels,
and the mean PIDAQ scores. To test the impact of each demographic variable, self-rated
IOTN, clinician-rated IOTN and DAI on the PIDAQ scores, nonparametric statistics (Kruskal–Wallis
and Mann–Whitney) were used as the data did not follow a normal distribution when
the normality test was checked with the Shapiro-Wilk test. Multiple linear regression
analysis was used to test the influence of the aforementioned variables on the PIDAQ
scale and subscales. The significance level was set at p<0.05. SPSS 14.0 for Windows (SPSS Inc., Chicago, Illinois, United States) was used
for the statistical analysis. To test the internal consistency of the PIDAQ questionnaire,
Cronbach's α was calculated for the scale as a whole and for each individual domain.
Cronbach's α for the scale was 0.86, thus indicating good internal consistency.
Results
The total number of participants who completed the questionnaires was 355 out of 400
participants who were invited to participate (88.75% response rate), of which 152
were males and 203 were females. The distribution of the sample's sociodemographic
characteristics, including age, sex, marital status, and self-rated and clinician-rated
malocclusion levels, is presented in [Table 1].
Table 1
Descriptive statistics showing demographics, self-rated malocclusion severity (IOTN),
and clinician-rated malocclusion severity (IOTN and DAI) of the sample
|
Variable
|
Subcategories
|
N (%)
|
|
Age
|
18–22
|
165 (45.5%)
|
|
23–26
|
109 (30.7%)
|
|
27–30
|
76 (21.4%)
|
|
Sex
|
Male
|
152 (42.8%)
|
|
Female
|
203 (57.2%)
|
|
Marital status
|
Single
|
292 (82.3%)
|
|
Married
|
45 (12.7%)
|
|
Divorced
|
9 (2.5%)
|
|
Engaged
|
9 (2.5%)
|
|
Self-rated IOTN
|
Mild malocclusion
|
292 (82.3%)
|
|
Moderate malocclusion
|
44 (12.4%)
|
|
Severe malocclusion
|
19 (5.4%)
|
|
Clinician-rated IOTN
|
Mild malocclusion
|
298 (83.9%)
|
|
Moderate malocclusion
|
39 (11.0%)
|
|
Severe malocclusion
|
18 (5.1%)
|
|
DAI
|
Minor malocclusion/no treatment needed
|
298 (83.9%)
|
|
Definite malocclusion/treatment elective
|
20 (5.6%)
|
|
Severe malocclusion/treatment highly desirable
|
15 (4.2%)
|
|
Very severe malocclusion/treatment mandatory
|
22 (6.2%)
|
Abbreviations: DAI, Dental Aesthetic Index; IOTN, Index of Orthodontic Treatment Need.
Overall, the total mean score (SD) for the PIDAQ in the current study was 37.02 (SD=24.16)
with the highest rating given to the dental self-consciousness domain (11.61, SD=7.37)
followed by the aesthetic attitude (10.20, SD=9), SI (7.63, SD=6.91), and PI (7.60,
SD=5.1) domains, respectively (see [Table 2]).
Table 2
Mean and SD for PIDAQ subscale and total scores
|
PIDAQ domain
|
Mean
|
SD
|
Range
|
|
Dental self-consciousness total score:
|
11.61
|
7.37
|
0–24 (24)
|
|
Social impact total score:
|
7.63
|
6.91
|
0–24 (24)
|
|
Psychological impact total score:
|
7.60
|
5.10
|
0–16 (16)
|
|
Aesthetic attitude total score:
|
10.20
|
9.00
|
0–28 (28)
|
|
PIDAQ total score
|
37.02
|
24.16
|
0–92 (92)
|
Abbreviations: PIDAQ, Psychosocial Impact of Dental Aesthetics Questionnaire; SD,
standard deviation.
[Table 3] displays the influence of different sociodemographic characteristics on the results
of the PIDAQ scores. While age and marital status did not show any significant effect
on PIDAQ scores, sex on the other hand did, where females were significantly more
impacted than males on all domains (p<0.0001).
Table 3
Comparison of mean PIDAQ subscale and total scores among different sociodemographic
variables
|
Variable
|
Subcategories
|
DSC,
mean (SD)
|
p-Value
|
SI,
mean
(SD)
|
p-Value
|
PI, mean (SD)
|
p-Value
|
AC, mean (SD)
|
p-Value
|
Total PIDAQ, mean (SD)
|
p-Value
|
|
Age
|
18–22
|
12.0±7.5
|
0.134
|
7.4±7.1
|
0.724
|
7.9±5.1
|
0.652
|
9.5±8.7
|
0.437
|
36.7±15.9
|
0.302
|
|
23–26
|
12.1±7.3
|
7.6±6.5
|
7.5±5.0
|
10.4±8.9
|
37.1±14.9
|
|
27–30
|
10.1±7.1
|
8.2±6.5
|
7.3±5.3
|
11.3±9.7
|
40.1±17.5
|
|
Sex
|
Male
|
10.1±7.1
|
0.001[a]
|
6.0±6.3
|
0.000[a]
|
6.0±4.5
|
0.000[a]
|
8.0±8.3
|
0.000[a]
|
33.2±15.2
|
0.000[a]
|
|
Female
|
12.7±7.4
|
8.8±7.1
|
8.8±5.2
|
11.8±9.1
|
40.7±15.8
|
|
Marital status
|
Single
|
11.8±7.4
|
0.411
|
7.6±6.9
|
0.942
|
7.5±5.1
|
0.118
|
9.9±8.9
|
0.550
|
36.8±15.8
|
0.341
|
|
Married
|
10.1±7.1
|
7.8±7.0
|
7.2±5.3
|
11.0±9.9
|
40.0±17.2
|
|
Divorced
|
11.2±8.2
|
6.9±6.7
|
8.9±2.7
|
10.4±8.6
|
39.0±17.0
|
|
Engaged
|
13.6±6.4
|
8.8±7.1
|
11.2±4.7
|
14.0±7.6
|
44.4±14.2
|
Abbreviations: AC, aesthetic concern; DSC, dental self-confidence; PI, psychosocial
impact; SI, social impact.
a Statistically significant.
[Table 4] displays the influence of different self-rated and clinician-rated malocclusion
levels on the results of the PIDAQ score. For both the self-rated and clinician-rated
IOTN, it was found that participants with moderate and severe malocclusions were significantly
more impacted on all domains including the PIDAQ total score (p<0.0001 and p<0.001) except the DSC domain which showed that individuals with mild malocclusion
levels were more effected than those with moderate and severe malocclusions (p<0.0001).
Table 4
Comparison of mean PIDAQ subscale and total scores among different self-rated and
clinician-rated malocclusion severity levels
|
Variable
|
Subcategories
|
DSC,
mean (SD)
|
p-Value
|
SI,
mean (SD)
|
p-Value
|
PI,
mean (SD)
|
p-Value
|
AC,
mean (SD)
|
p-Value
|
Total PIDAQ, mean (SD)
|
p-Value
|
|
Self-rated IOTN
|
Mild
|
13.3±7.03
|
0.000[a]
|
6.7±6.4
|
0.000[a]
|
6.9±5.0
|
0.000[a]
|
8.6±8.2
|
0.000[a]
|
35.5±15.4
|
0.000[a]
|
|
Moderate
|
6.89±5.8
|
12.0±6.8
|
10.8±5.0
|
17.3±7.9
|
46.9±14.8
|
|
severe
|
4.6±5.5
|
12.3±9.3
|
10.9±4.3
|
18.9±9.4
|
46.7±17.3
|
|
Clinician-rated IOTN
|
Mild
|
12.9±7.1
|
0.000[a]
|
6.9±6.5
|
0.000[a]
|
7.2±5.1
|
0.009[a]
|
8.8±8.4
|
0.000[a]
|
35.9±15.1
|
0.000[a]
|
|
Moderate
|
8.1±6.9
|
11.0±6.7
|
9.7±4.4
|
17.5±8.5
|
46.2±17.0
|
|
Severe
|
6.8±7.2
|
12.5±9.2
|
8.7±5.3
|
16.9±9.7
|
44.9±20.3
|
|
DAI
|
Minor malocclusion
|
12.7±7.3
|
0.000[a]
|
7.0±6.5
|
0.001[a]
|
7.0±5.0
|
0.000[a]
|
8.9±8.3
|
0.000[a]
|
35.5±14.8
|
0.000[a]
|
|
Definite malocclusion
|
10.2±6.5
|
9.0±7.3
|
11.0±4.1
|
14.9±9.0
|
45.1±16.6
|
|
Severe malocclusion
|
10.7±8.0
|
11.0±8.6
|
10.6±5.1
|
16.3±9.2
|
48.7±20.2
|
|
Very severe malocclusion
|
6.8±6.7
|
13.3±8.0
|
10.3±4.9
|
18.9±10.0
|
49.3±17.6
|
Abbreviations: AC, aesthetic concern; DSC, dental self-confidence; PI, psychosocial
impact; SI, social impact.
a Statistically significant
This was also the case with the DAI where it was found that those with minor malocclusions
showed significantly higher dental self-consciousness scores than those with definite,
severe, and very severe malocclusions (p<0.0001). However, for all other domains, it was found that the more severe the malocclusion
(i.e., higher treatment need), the greater the impact (p<0.001 and p<0.0001).
[Table 5] displays the linear regression model analysis which revealed that sex, age, self-rated
IOTN, and DAI were significant predictor variables of PIDAQ scores (p<0.05). However, clinician-rated IOTN was not significant at p=0.929. The analysis revealed an intermediate R-value (0.431) and that the model is capable of explanation of 18.6% of the variance
of PIDAQ values. Durbin–Watson and multicollinearity analyses revealed no serial correlation
in the model (i.e., Durban–Watson value between 1.5 and 2.5, and tolerance values
of more than 0.8 for all variables).
Table 5
Multiple linear regression analysis for the association of total PIDAQ score and independent
variables
|
Dependent variable
|
Independent variables
|
Unstandardized coefficients
|
Standardized coefficients
|
t
|
Sig.
|
95.0% confidence interval for B
|
|
B
|
Std. error
|
Beta
|
Lower bound
|
Upper bound
|
|
Total PIDAQ score[a]
|
(Constant)
|
3.997
|
6.311
|
|
0.633
|
0.527
|
−8,414
|
16.409
|
|
Self-rated IOTN[b]
|
4.461
|
1.611
|
0.149
|
2.769
|
0.006
|
1.293
|
7.629
|
|
Clinician-rated IOTN
|
0.164
|
1.857
|
0.005
|
0.089
|
0.929
|
−3.488
|
3.817
|
|
Age
|
0.458
|
0.219
|
0.102
|
2.093
|
0.037
|
0.028
|
0.888
|
|
Sex[c]
|
6.343
|
1.585
|
0.197
|
4.003
|
0.000
|
3.227
|
9.460
|
|
DAI[d]
|
0.430
|
0.098
|
0.264
|
4.389
|
0.000
|
0.237
|
0.622
|
Abbreviations: DAI, Dental Aesthetic Index; IOTN, Index of Orthodontic Treatment Need.
Note: Dependent variable: PIDAQ scores.
a As PIDAQ increases, psychosocial impact of malocclusion increases.
b As Self -rated IOTN increases, need for treatment increases.
c Sex: 0=boy, 1=girl.
d As DAI increases, need for treatment increases.
Discussion
Over the past four decades there has been increasing interest in patient-centered
outcome studies especially when evaluating OHQoL. This has been stressed by the World
Health Organization as an area of interest and is considered as one of the factors
that resulted in an increase in QoL research across many fields including the dental
field. As more and more OHQoL studies are conducted, it has become apparent that factors
such as oral health, malocclusion, and treatment can significantly affect a patients'
QoL.[21] Although the impact of malocclusion on the OHQoL is well documented, there is still
conflicting evidence about the impact of malocclusion on the psychosocial well-being
of an individual and how clinician-rated and self-rated malocclusion levels differ
in their impact. The current study evaluated the impact of self-rated and clinician-rated
malocclusion levels on the psychosocial well-being of a young adult population using
the Arabic version of the PIDAQ instrument which has been previously cross-culturally
adapted and validated for an Arabic-speaking population.[16]
The mean PIDAQ score obtained for the study sample was 37.8±15.76, which, when compared
with previous studies including those with a similar population sample, is considered
low indicating a low impact of malocclusion on the psychosocial well-being of the
participants.[14]
[22]
[23] This could be due to the fact that the majority of the sample had a mild malocclusion
(as rated by the IOTN) or no treatment need (as rated by the DAI), which may have
resulted in lower psychosocial impacts.
The results did not show any significant association between PIDAQ scores and marital
status, which is contradictory to previous studies that found that those who are married/in
a relationship showed higher DSC scores, whereas those who were single were significantly
impacted in the SI and PI domains.[15] The reason for the contradictory results may be due to the small number of participants
who were married compared with those who were single in the current study sample,
which one would expect considering that the majority of the participants were between
the ages of 18 and 26.
Similarly, age did not show significant association with the PIDAQ scores, which agrees
with several studies.[16]
[18] The age intervals used for the current study were not completely equal, where the
first group was 18 to 22 (5 years) while the other two groups were 22 to 26 (4 years)
and 27 to 30 (4 years), which may be a contributing factor for the lack of association.
However, this interval was used following previous studies to enhance comparability.[16]
With regard to gender, the results revealed that females were significantly more impacted
on all domains than males. This is not a rare finding as several studies have reported
that malocclusion might have significantly more psychosocial impact on females compared
with males. Studies that have examined the association between aesthetics and gender
have concluded that women are generally more demanding with regard to beauty and aesthetics,
more affected by what they consider facial and corporal aesthetic defects, and more
critical in general regarding everything related to aesthetics.[1]
[5]
[18]
[24]
[25]
As for the effect of malocclusion on the psychosocial well-being of the sample, our
study confirms that the more severe the malocclusion is, the higher the impact on
all domains including the PIDAQ total score, with the exception of the DSC domain
which showed a negative correlation. While previous studies have reported that higher
orthodontic treatment need resulted in higher negative psychosocial impacts and a
worse QoL compared with those who have no treatment need, it is unclear why this does
not apply to the DSC domain in the current study.[22]
[26] One explanation could be that those with low need for treatment have malocclusions
that are not severe enough to cause impacts on the psychological, social, and aesthetic
domains however, resulted in them being more aware and specific about the appearance
of their teeth.
Multiple linear regression analysis showed that sex, age, self-rated IOTN, and DAI
were predictors associated with psychosocial impacts confirming the results of previous
studies that psychosocial impacts of dental aesthetics are multifactorial and are
influenced by measures of normative orthodontic treatment need as well as subjective
aspects.[18]
[27] The regression models' global fit was summarized using the R2 values, which reflect to what extent the proportion of the PIDAQ's scale variability
can be attributed to a linear combination of the explanatory variables selected in
this study. The results showed that the explanatory variables explained around 18.6%
of the overall PIDAQ scale variation. However, the interpretation of the results based
on the R2 values demands some degree of caution as a significant portion of the variability
can be due to unidentified variables or inherent variability in the data. In other
words, caution must be used in assessing how significant the independent variables
are in predicting the self-perceived psychosocial impact of dental aesthetics for
young adults, and the individual patient's psychological and clinical aspects must
also be taken into account.
On interpreting the results of the present study, it is important to highlight its
limitations. Although the PIDAQ scale was psychometrically tested and cross-culturally
adapted for a Saudi population, little is known about the stability of the scale over
time and could be a study objective of future projects. In addition, the study was
single-centered and hence, generalizability of the results should be considered with
caution. However, the sample size was considered sufficient to overcome the selection
bias. It is also important to note that the majority of the participants had malocclusions
that were considered mild or no need for treatment, this could be because both the
AC of IOTN and the DAI may not adequately capture all malocclusion traits and hence
it may prove beneficial to include more detailed means of measuring malocclusion.
Nevertheless, perceived dental and facial aesthetics is multifactorial and might be
affected by other variables that were not examined in the study whether in the past
or how aesthetically demanding their current social status is (e.g., lifestyle, careers,
etc.), which could be an interesting area for future research.
Conclusion
Perceived psychosocial impact of dental aesthetics is directly related to severity
of malocclusion (self-rated and clinician-rated) for all domains of the PIDAQ with
the exception of the DSC domain. Age, sex, self-rated IOTN, and clinician-rated DAI
are significant predictors of the total PIDAQ score. Clinicians should consider the
impact of malocclusion and certain demographic characteristics on the psychosocial
well-being of an individual when determining the orthodontic treatment need.
