Orthodontic treatment need and perception: A comparative study between different socio-economic groups of patients

Inclusion criteria

• Subjects attending with one and/or both parents were included in the study.

Exclusion criteria

• Subjects attending alone were excluded from the study.

• Subjects whose parents had received orthodontic treatment were excluded from the study.

• Subjects who reported with craniofacial anomalies were excluded from the study.

In total, 45 subjects were excluded based on the selection criteria.

The parents were provided with a set of questionnaires according to their preferred languages (Bengali/Hindi/ English) for assertion and evaluation of SES and self-perception. Perceived treatment need was assessed by the parents themselves using IOTN aesthetic component (AC) score.

Normative treatment need of the subjects was determined by the clinician using the AC and Dental Health Component (DHC) of the IOTN, which was kept blind to the socioeconomic background of the subjects.

The IOTN is an internationally acknowledged scoring system for orthodontic treatment need, as perceived by the professionals and patients. The IOTN incorporates both a DHC (Brook and Shaw, 1989)^[8] and an AC (Evans and Shaw, 1987).^[9]

The DHC records various occlusal traits in five grades according to the severity and the need for orthodontic treatment (Brook and Shaw, 1989).^[8] Grades 1 and 2 represent no/little need for treatment, Grade 3 gives a borderline assessment, whereas Grades 4 and 5 represent a definite need for orthodontic treatment.

The AC has a scale of 10 color photographs representing different levels of dental attractiveness, with Grade 1 representing the most attractive and Grade 10 representing the least attractive (Evans and Shaw, 1987).^[9]

The parents (both in agreement with each other, wherever applicable) were asked to make a judgment about how severe they rated their child’s dental attractiveness.

For evaluation of the AC, the classification by Richmond et al. (1995)^[10] was used, where Grades 1–4 represented no or little esthetic need, Grades 5–7 borderline esthetic need, and Grades 8–10 represented a definite esthetic need for orthodontic treatment.

Self-perception of oral esthetics was assessed by subjects using the Oral Aesthetic Subjective Impact Scale (OASIS). This indicator was developed by Mandall et al.^[11]

The OASIS measures the impact of external influences in childhood by asking questions concerning the perceptions of others and themselves, as well as about their teeth. The subjects had to answer five questions on a 7-point Likert scale, and points awarded to all the questions were added to provide an overall oral esthetic impact score as perceived by each subject. This variable was dichotomized by the medians as positive self-perception (OASIS <18) and negative self-perception (OASIS >19).^[11]

Assessment of the SES

Kuppuswamy socioeconomic scale is the most widely used socioeconomic scale all over India. This scale has been endlessly revised over the years because the income categories in the scale lose their scoring following the change in the value of the rupee. Therefore, there is a need to update the scale as per the changes in consumer price index.^[12] The Kuppuswamy SES has included three parameters and each parameter is further classified into subgroups and scores have been allotted to each subgroup. The total score of Kuppuswamy SES ranges from 3 to 29.

The SES was calculated using modified Kuppuswamy scale updated for year 2018^[12].

This was mainly based on the occupation of the head of the family, education of the head of the family, and total monthly income of the family. Each variable was given a weight, the total of which established the socioeconomic weight. Cutoff points divided SES into five groups; lower, upper lower, lower middle, upper middle, and upper.

Reliability

To determine the method error (intraexaminer agreement), 40 subjects were reexamined 1 month after the initial examination (for subjects who started receiving the orthodontic treatment). Kappa values for the DHC and the AC were 0.92 and 0.76, respectively.

Statistical analysis

For statistical analysis, data were entered into a Microsoft Excel spreadsheet and then analyzed by SPSS (version 24.0; SPSS Inc., Chicago, IL, USA) and GraphPad Prism version 5.

Data had been summarized as percentages (frequencies) for categorical variables.

A Chi-squared test (χ² test) was done for statistical hypothesis test wherein the sampling distribution of the test statistic is a Chi-squared distribution when the null hypothesis is true.

The association between the AC scores of the IOTN, DHC, and the characteristics of the subjects was tested with Spearman’s correlation coefficient (rho). P ≤ 0.05 was considered as statistically significant.

Distribution of the data sample

In this study, a total of 212 subjects were taken, which included 125 (59.0%) female subjects and 87 (41.0%) male subjects [Table 1].

Distribution of socioeconomic group based on modified Kuppuswamy socioeconomic scale 2018 was found to be as follows: 20 (9.4%) subjects were in upper SES, 98 (46.2%) in upper middle SES, 62 (29.2%) in lower middle SES, 30 (14.2%) in upper lower SES, and 2 (0.9%) in lower SES [Table 1].

The percentage distribution of the DHC of the IOTN as scored by the clinician was found to be as follows: 10.8% of the subjects had no/little need of DHC, 24.5% of the subjects had borderline DHC, and 64.6% of the subjects had definite need of DHC [Table 1].

According to the clinician measured AC scoring, 52 (24.5%) subjects had definite need, 77 (36.3%) subjects had borderline, and 83 (39.2%) subjects had no/little esthetic need [Table 1].

On the other hand, parents AC scoring is as following, 48 (22.6%) subjects exhibited definite need, 70 (33.0%) subjects borderline, and 94 (44.3%) subjects no/little need [Table 1].

Oral esthetic self-perception had negative perception in 118 (55.7%) subjects whereas positive perception was found in 94 (44.3%) subjects as assessed by OASIS [Table 1].

The relationship between normative orthodontic treatment need (clinician-measured DHC and AC) and perceived treatment need (parent AC)

Severity of malocclusion as measured by DHC was found to be much higher in male subjects than in females.

About 93.1% of male subjects scored in borderline and definite need groups as measured by the clinician.

On the contrary, 86.4% of females reported in the borderline and definite need groups. Association of gender and DHC was statistically significant (P = 0.0348).

Comparison of normative treatment need (clinician-measured AC) with perceived treatment need showed the former to be most critical of malocclusions. The clinician allocated more subjects to the borderline and definite need categories (60.8%) than parents (P = 0.0001) [Table 2].

There was a significant correlation between DHC and the clinician-rated AC of the IOTN (Spearman’s correlation coefficient, rho: 0.581, P < 0.001).

Orthodontic treatment need and SES

Association of SES group and DHC group was not found to be statistically significant (P = 0.3958) which represents the severity of malocclusion to be distributed homogeneously throughout the socioeconomic group.

The role of SES of the parent does not seem to affect the normative (clinician-measured AC) and perceived treatment need (parent AC) (P = 0.3447) (P = 0.8372) [Table 3].

OASIS and gender, age

The self-perception of the subjects as measured by the OASIS scale is not influenced by the socioeconomic status which means that familial income, occupation of the parent, and education have little role to play with the perception of the malocclusion (P = 0.8800) [Table 4].

Oral esthetic self-perception as measured by the OASIS did not show any difference across the three age groups and between genders (P = 0.2315), (P = 0.495).

Normative orthodontic treatment need

The severity of malocclusion as measured by DHC was much higher in male subjects than in females.

However, Badran et al. (2010)^[18] found that 65% of the females reported in the borderline and definite need groups compared to 51.1% males. No association was found between gender and DHC grades as per study conducted by Doğan et al. (2010).^[19]

This seems to suggest that males seek orthodontic treatment only when their malocclusion is severe. This may be a reflection of sex role stereotyping, wherein society places a greater emphasis on the importance of physical attractiveness in females, compared to males (Shaw et al., 1991).^[20]

According to the clinician’s findings, 64.6% had a definite orthodontic treatment need (DHC), while 24.5% of the subjects had a severe esthetic need (AC).

The DHC of the IOTN was higher than the AC of the IOTN when recorded by the clinician (Spearman’s correlation coefficient, rho: 0.581, P < 0.001). The reason for this difference is the registration of two different attributes: The DHC is based on occlusal characteristics, whereas the AC determines treatment need purely on esthetic grounds (Brook and Shaw, 1989).^[8]

Comparison of normative and perceived treatment need

The clinician allocated more subjects to the borderline and definite need categories (60.8%) than parents which is higher than the value found by Hamdan (2004).^[17]

Similarly, Badran (2010)^[18] suggested that subjects in their study were less critical in their esthetic evaluation (AC score) than the examiner, which corresponds with many other studies (Evans and Shaw, 1987; Shaw et al., 1991; Burden and Pine, 1995; Kerosuo et al., 2004; Abu Alhaija et al., 2005).^[21]

The relationship between orthodontic treatment need and socioeconomic groups

In the current study, socioeconomic status of the parents did not seem to affect their perception of dental appearance. Normative treatment need and perceived treatment need have been uniform throughout the different socioeconomic groups (P = 0.3447 and P = 0.8372).

The Indian subcontinent is home to people with a wide range of socioeconomic status. With a staggering population of 1.36 billion (2019), the variation in the different socioeconomic strata is obvious. Attempts have been made over the years to classify these strata of which the modified Kuppuswamy scale has been used in this study. Thus, although similar findings have been reported in some studies such as Platia and Khanna (2016),^[22] Doğan et al. (2010),^[19] Christopherson et al. (2009),^[2] Kerosuo et al. (2004),^[6] and Bergström et al. (1998),^[23] the findings reported here are unlike the others because of the price sensitivity prevalent across the different socioeconomic strata of Indian population. The perception of orthodontic treatment need remains analogous regardless of the higher qualification and high-income parents which may be due to the lack of awareness among the people regarding the dental malocclusion and its negative impact on the psychosocial well-being.

Devi et al. (2009)^[24] reported that familial SES is not a determinant in children’s satisfaction with dental appearance. Likewise, children with different SES demonstrate that they have almost completely the same approach toward braces. Burden (1995)^[25] and Burden and Pine (1995)^[26] found the role of peer groups to be more important for determining orthodontic treatment than social class or sex.

One study stated that the influence of SES on perceived and normative orthodontic treatment need remains unclear.^[27]

Self-perception and age, gender

In this study, oral esthetic self-perception as measured by the OASIS did not show any difference across the three age groups and between genders (P = 0.2315).

This finding is in unison with the studies which suggest that the perceived need was not influenced by sex.^[28,29]

Marques et al. (2009)^[13] did not find any significant associations between esthetic impact and gender, age group, or self-esteem. This suggests that adolescents perceive the psychosocial effect of malocclusion in a homogeneous fashion.

However, other studies have found that females are stricter with regard to the self-perception of facial esthetics than males.^[12,30,31] These differences may be explained by differences in study designs, measures, age groups, and populations.

Self-perception and socioeconomic groups

In this study, association between OASIS group and socioeconomic status was not statistically significant (P = 0.8800).

This seems to suggest that self-perception of appearance is uniform among different SES groups.

To the best of our knowledge, no comparison has been attempted before to report the association between self-perception as measured by OASIS scale and SES.

Limitations of the study

The present study has limitations such as:

• The subjects were selected from among the parents who reported to the Department of Orthodontics and Dentofacial Orthopedics, of Guru Nanak Institute of Dental Sciences and Research, Kolkata. Hence, they may not be the representative of the general population. The findings can only be applied to the subjects seeking orthodontic treatment. A large population comprising different demographic areas would have resulted in equal distribution of subjects in the socioeconomic groups.

• We must also pay attention before generalizing these results, as cultural variances between various study samples may influence perceptions of esthetics and treatment need.