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ORIGINAL ARTICLE
Year : 2021  |  Volume : 19  |  Issue : 1  |  Page : 4-9

Assessment of the correlation between the perceived, desired, and normatively determined orthodontic treatment needs in a rural population of India


1 Department of Public Health Dentistry, Uttaranchal Dental and Medical Research Institute, Dehradun, Uttarakhand, India
2 Department of Public Health Dentistry, Institute of Dental Studies and Technologies, Ghaziabad, Uttar Pradesh, India
3 Department of Oral Pathology and Microbiology, Uttaranchal Dental and Medical Research Institute, Dehradun, Uttarakhand, India
4 Department of Dentistry, Atlas College of Health Sciences, Addis Ababa, Ethiopia

Date of Submission25-Mar-2020
Date of Acceptance08-Feb-2021
Date of Web Publication31-Mar-2021

Correspondence Address:
Jyoti Singh
Department of Public Health Dentistry, Uttaranchal Dental and Medical Research Institute, Majri Grant, Dehradun - 248 140, Uttarakhand
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiaphd.jiaphd_54_20

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  Abstract 


Background: The perception about what constitutes a pleasing smile varies from person to person. The problem of crooked teeth may not be perceived as an actual need for treatment by some, and may differ not only on an individual basis, but also from a geographic perspective. Aim: The aim of the study was to assess if orthodontic treatment needs correlated with the actual self-perception and desire for orthodontic treatment in a rural population and was there an influence of gender and age. Materials and Methods: The study population included 495 older adolescents and younger adults between the age group of 16–24 years, randomly selected from villages in Dehradun. They were asked about their desire for orthodontic treatment and evaluated through the esthetic component of Index of Orthodontic Treatment Need (IOTN-AC) and the Dental Aesthetic Index (DAI). Bivariate analyses using the Chi-square test were performed (SPSS software [version 17.0]) to test the influence of age and gender on desired, perceived, and normative needs. Associations between the different needs were tested using both simple and multiple logistic regression analysis. P < 0.05 was considered to be statistically significant. Results: Approximately 48.1% of the study population showed a desire for orthodontic treatment for their teeth. For perceived needs assessed through IOTN-AC, 11.91% indicated a definite need for orthodontic treatment. The DAI scores estimated the normative treatment needs with 25.86% indicating a mandatory need for orthodontic treatment. Gender and age differences influenced desired need (P = 0.017; P = 0.014) but had no relation with perceived (P = 0.269; P = 0.058) or normatively determined orthodontic treatment needs (P = 0.093; P = 0.087). Conclusion: Statistically significant association was observed between the normative needs and desire for orthodontic treatment. Gender and age differences influenced desired needs only.

Keywords: Desired needs, malocclusion, normative needs, orthodontic treatment needs, perceived needs


How to cite this article:
Rekhi A, Singh J, Dadu M, Singh S, Rai A, Rai V. Assessment of the correlation between the perceived, desired, and normatively determined orthodontic treatment needs in a rural population of India. J Indian Assoc Public Health Dent 2021;19:4-9

How to cite this URL:
Rekhi A, Singh J, Dadu M, Singh S, Rai A, Rai V. Assessment of the correlation between the perceived, desired, and normatively determined orthodontic treatment needs in a rural population of India. J Indian Assoc Public Health Dent [serial online] 2021 [cited 2021 Jun 13];19:4-9. Available from: https://www.jiaphd.org/text.asp?2021/19/1/4/312646




  Introduction Top


Well-aligned teeth and a pleasing smile reflect positively at all social levels while irregular or protruding teeth have an opposite effect.[1],[2] Dissatisfaction with one's dentofacial appearance, recommendations from a dentist, concern on the part of parents and the influence of schoolmates who wear braces are among the main factors directly involved in the demand for orthodontic treatment.[3]

The perception of beauty is not only just an individual preference, but also might have cultural and ethnic biases.[4],[5],[6] It has also been suggested that gender; socioeconomic background and age are factors playing a role in the self-perception of dental appearance.[7],[8]

Personal esthetic perceptions of the dentofacial complex and the associated psychosocial need are relevant to the consumers of orthodontic care.[9] Although dissatisfaction with dental appearance is broadly related to the severity of the occlusal irregularities,[1] there are differences in the recognition and evaluation of the dental features.[10] For this reason, professional opinions regarding evaluation of facial esthetics may not coincide with the perceptions and expectations of patients or lay people.[11],[12] However, subjective psychosocial perceptions play an important role in orthodontics, if the patient receives satisfactory treatment improving function and esthetics, might be more influenced by demand than by need.[13]

Malocclusion can be considered a public health problem due to its high prevalence and prevention/treatment possibilities. Therefore, the importance of patients' perceptions regarding orthodontic treatment cannot be underestimated. Hence, in systems of orthodontic care delivery where treatment priorities must be made, for financial or other reasons, or during counseling, the patient's perception is of great importance.

Self-perception and consciousness of body image may increase with age,[14],[15] older adolescents and young adults are considered to be a relevant age group for the study of personal dental appearance perception. While there have been studies done on children and young adults in urban setup,[9],[16],[17] studies addressing the perception of malocclusion regarding the rural backdrop are lacking specially in a developing nation like India.

Hence, the need of the study is to assess the correlation between perceived, desired, and normatively determined orthodontic treatment needs based on gender and age among a rural population in India.


  Materials and Methods Top


The study protocol was approved by the Institutional Ethical Committee (No IEC/PA-003/2017 dated May 18, 2017) and voluntary consent was obtained from each participant before the study.

A cross-sectional study was carried out to assess the perceived, desired, and normative determined treatment needs among 16–24 year old subjects selected from the rural population of Dehradun district in India. A pilot study was conducted to check the feasibility of the methodology planned and for sample size estimation.

A pilot study was conducted to check the feasibility of the methodology planned and for sample size estimation. It was done on 74 subjects residing in two villages.

The sample size was determined by the following equation: N = Zα2 (p [1-p])/L2

Where, N = size of sample, Zα = critical value at 95% confidence level = 1.96, P = prevalence of highly desirable and mandatory orthodontic treatment indication, L = maximal permissible error = 5%.

A sample size of 495 was calculated to be satisfactory to detect an odds ratio of at least 2 considering the prevalence of desire for orthodontic treatment of 20% among those who were having “no” or “slight” orthodontic treatment need (Dental Aesthetic Index [DAI] <30), a Type I error of 5%, a statistical power of 80% and allowance of 10% refusal.

A stratified two-stage cluster sampling technique with villages as the primary sampling unit was utilized. Subjects with the presence of mixed dentition, any structural abnormality in the teeth concerned and those who were undergoing or had undergone any orthodontic treatment previously were excluded.

Three types of variables were assessed:

  • The desired need for orthodontic treatment was determined by asking the subjects if they felt that they needed any orthodontic treatment or rather would like to have their teeth straightened. The subjects answered “yes” or “no”
  • The perceived need for orthodontic treatment was assessed using the esthetic component of Index of Orthodontic Treatment Need (IOTN-AC).[18] In this, each subject was shown 10 colored photographs depicted in the AC of IOTN and the subject had to choose which of these photograph had the closest resemblance to their actual smile. This was done on a memory recall basis and the subjects were not allowed to check their smile in the mirror. The score of the photograph chosen was recorded. Here, a definite need of treatment is represented by photos 8–10, borderline need for treatment by photos 5–7 and no need for orthodontic treatment is represented by photos 1–4
  • The normative need for orthodontic treatment was determined using the DAI.[19] The DAI criteria help determines the dentofacial anomalies. The collection of data according to this criteria permits analysis to be made of each of the separate components of the index or grouped under anomalies of dentition, space, and occlusion. It is also possible to calculate standard DAI scores using the DAI regression equation whereby the measured components of the DAI are multiplied by their regression coefficients, the products then being added to the regression equation constant. The resultant sum is the standard DAI score.


The regression equation used for calculating standard DAI scores is as follows:

(missing visible teeth X 6) + (crowding) + (spacing) + (diastema X 3) + (largest anterior maxillary irregularity) + (largest anterior mandibular irregularity) + (anterior maxillary overjet X 2) + (anterior mandibular overjet X 4) + (vertical anterior open bite X 4) + (anteroposterior molar relation X 3) +13.

The severity of malocclusion on the basis of the DAI scores is shown in [Table 1].
Table 1: The severity of malocclusion on basis of the Dental Aesthetic Index scores

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All measurements were performed by a single calibrated examiner. The intra-examiner tests were performed in the measurement of the DAI. Reliable results were seen with kappa values of 0.82.

The data were entered into the Excel sheet (MS Office 2007) and then analyzed using the SPSS® software version 17.0 (SPSS Inc; Chicago, IL, USA). Bivariate analyses using the Chi-square test at 5% significance level were performed to test the influence of age and gender on desired, perceived and normative orthodontic treatment needs. Associations between the dependent variable, i.e., desire for orthodontic treatment need and two independent variables, i.e., perceived orthodontic treatment need and normative orthodontic treatment need, were tested using both simple and multiple logistic regression analysis. For the purpose of logistic regression, the independent variable of perceived orthodontic treatment need was dichotomized into “no/borderline need” (depicted by photos 1–7) and “definite need” (depicted by photos 8–10). The independent variable of normative orthodontic treatment need was dichotomized into “no or elective need” (DAI score <30) and “highly desirable and mandatory need” (DAI score >30). P < 0.05 was considered to be statistically significant.


  Results Top


Out of total sample of 495, 53.33% (264) were male and 46.67% (231) were female [Table 2].
Table 2: Distribution of the study subjects according to gender and age (groups of 16 to 18 years age; above 18 years age)

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Desired needs were found to be significantly (P = 0.017) more in females compared to males whereas, gender-wise differences were not found to be statistically significant in relation to the perceived needs (P = 0.269) and normative needs (P = 0.093) [Table 3].
Table 3: Distribution of subjects according to gender in relation to their desired, perceived (Index of Orthodontic Treatment Need - Aesthetic Component) and normatively determined needs (Dental Aesthetic Index) for orthodontic treatment

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Similarly, desired needs were found to be significantly (P = 0.014) more in 16–18 years of age group compared to more than 18 years whereas other age group differences were not found to be statistically significant in relation to the perceived needs (P = 0.058) and normative needs (P = 0.087) [Table 4].
Table 4: Distribution of subjects according to age groups in relation to their desired, perceived (Index of Orthodontic Treatment Need - Aesthetic Component) and normatively determined needs (Dental Aesthetic Index) for orthodontic treatment

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Based on the univariate and multivariate logistic regression analyses, the associations between the “desire” for orthodontic treatment and “normative” and “perceived” orthodontic treatment needs were calculated. It indicated that the odds of subjects with severe/handicapping malocclusion showing desire for orthodontic treatment were 8.63 times than that of subjects with no/borderline treatment need. When adjusted for age and gender, the odds ratio was found to be 9.26. Both adjusted and unadjusted odds ratio were found to be statistically very highly significant (P < 0.001) [Table 5].
Table 5: Univariate and multivariate logistic regression analyses considering associations between the desire for orthodontic treatment (dependent) and normative and perceived orthodontic treatment needs (independent)

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For perceived needs, the odds of subjects showing definite treatment need for desire of treatment were found to be 2.3 times than that of subjects showing no or borderline treatment need. When adjusted for age and gender, the odds ratio was found to be 2.2. Both adjusted and unadjusted odds ratio were found to be statistically not significant (P > 0.05) [Table 5].


  Discussion Top


The sample analyzed composed of older adolescents and younger adults aged between 16–24 years of age. This age group was selected since people of this age tend to be more socially aware and conscious about their appearance and looks than a comparatively younger school going population.

The comparison between the present and previously conducted studies is complicated, as the methods employed are different. Some studies have used the IOTN – Dental Health Component (IOTN-DHC)[9],[10],[20] to assess the normative treatment need instead of DAI which has been used in this study. Other studies have also used indices such as Standardized Continuum of Aesthetic Need component.[21] Oral Aesthetic Subjective Impact Scale[20],[22] or other questionnaires to assess the perceived needs instead of the IOTN-AC.

When gender-wise differences were seen for the desired orthodontic treatment need, females showed more desire as compared to males and these differences were found to be statistically significant. This is similar to a study conducted by Onyeaso and Arowojoln[22] whereas it is in contradiction to a study conducted by Marques et al.[23] It may be due to the fact that females tend to be more conscious about their appearances as compared to males and hence they reported a higher desire for orthodontic correction of their teeth.

The subjects in the age group of 16–18 years showed more desire toward orthodontic treatment whereas out of the subjects in the age group of 18 years and above, majority did not show a desire for the same. These differences were also found to be statistically significant, which is in contradiction to a study conducted by Marques et al.[23] Stenvik et al.[24] found that dissatisfaction with dental appearance and desire for orthodontic treatment decreased with increasing age, but more studies are required to assess age-related changes, which should be conducted longitudinally.

In this study, it appeared that the age and gender of the patients did not influence the perception of their own dentition. The female and male subjects of both age groups had the tendency to score their dental appearance more favorably and allocate themselves toward the more attractive end of the scale. When self-perceived orthodontic treatment need was evaluated by means of the AC of IOTN, only 11.91% subjects self-scored as presenting a definite need for orthodontic treatment. For gender-wise distribution, no statistically significant differences were observed in relation to the perceived needs which were similar to findings reported in a study by Bernabé and Flores-Mir.[9] Converse findings were seen in studies by Onyeaso and Arowojoln,[22], Oshagh et al.,[25] Aikins et al.[26] and Abu Alhaija et al.[27]

When age-wise comparisons were done, no statistically significant differences were found for perceived needs. Similar findings were observed in some other studies.[9],[25],[26] However, this is in contradiction with a study conducted by Abu Alhaija et al.[27] where significant differences were found when age groups were compared for the perceived need for treatment. Disease does not always negatively affect subjective perceptions of well-being, and even when it does, its impact depends on expectations, preferences, material, social, and psychological resources and more importantly, socially and culturally derived values.[28],[29] What is considered aesthetically pleasing in one culture will often not match that which is thought of as esthetically pleasing in another.[30] Thus, the lack of perceived need in the population evaluated might be due to the fact that this rural population probably does not have the same notions of beauty as their British peers, where the index was developed.

The univariate and multivariate analysis did not show any association between the self-perceived needs and the desire for orthodontic treatment. This was opposed by findings from other studies.[22],[23] It does not imply that perception and desire do not correlate. It may be due to certain limitations of the IOTN-AC index where only a fixed set of 10 photographs is shown and any other malocclusion conditions if present in an individual, makes it difficult for him to indicate the correct photograph score and the results can be skewed. It might be that patients could not estimate the malocclusion and subsequently could not classify the teeth in any of these grades. Further, it is likely that the IOTN-AC is not sensitive enough to account for all types of malocclusion as Class III, open bite, crossbite, and scissors bite.[16]

For normatively determined treatment needs, 45.25% of subjects in this study presented with highly desirable and mandatory treatment need according to the calculated DAI scores. When gender wise comparisons were done, men showed higher normative needs, but no statistically significant differences were observed, which was supported by those of previous studies conducted by Oshagh et al.[25] and Onyeaso and Arowojoln[22] In spite of conducting a thorough literature search, no study could be found in which age-wise differences were seen in relation to DAI scores. However, findings were in agreement to other studies,[25] which had used IOTN-DHC for the assessment of normative treatment needs and contradictory to some.[26]

Univariate and multivariate analysis between normatively determined needs and desire for orthodontic treatment revealed a statistically significant association between the two. Similar findings were also observed in studies conducted by Marques et al.[23] and Onyeaso and Arowojoln[22] The need of showing desire for orthodontic treatment was higher for those subjects who were assessed with severe/handicapping malocclusion. Thus, normatively determined orthodontic treatment need occurs as a significant predictor for desire for orthodontic treatment.

While esthetic indices help determine the perceptive component in treatment planning, they do come with certain limitations. Such indices are highly subjective and what one may feel pleasing might not look the same to the other. These indices may also be interpreted differently among the clinicians, patients, and their parents or guardians.[31],[32] We also must keep in mind that studies were conducted in populations where the difference in ethnic origins, socioeconomic status,[23] and education level[9] may influence the results and thus these can be potential limitations which should be considered and addressed in future studies.

Orthodontic problems should not be looked only through the clinical point of view but also have a public health perspective related to them, especially the preventive and interceptive aspects. This is truer for a rural community where access to dental care is anyway limited and people may ignore orthodontic issues. This in turn makes it more essential to address this issue and spread awareness about the same in this segment of the population.

For successful treatment, the opinion of the orthodontist should also correlate with what the patient actually wants out the procedure. Where a discrepancy exists, the patient should be educated appropriately and a consensus should be reached else patient's compliance may become an issue leading to unsuccessful outcomes. Hence, it is imperative that the desired, perceived, and normative needs of the patient should all be assessed before outlining the procedure for treatment. All forms of needs go hand-in-hand and it is better to modify one rather than ignore it to achieve the best clinical results.


  Conclusion Top


Gender- and age-wise differences influenced desire for orthodontics treatment but had no relation with perceived or normatively determined orthodontic treatment needs. Statistically significant association was observed between the normative needs and desire for orthodontic treatment. In summary, further studies are required to improve our understanding of normative and self-perceived need for orthodontic treatment, especially in developing countries where different factors than those reported in North American and European countries could be influencing the demand and delivery of orthodontic care. It may even be necessary to use more than one index in an epidemiological study to gather all the required information.

Financial support and sponsorship

All the armamentarium used for data collection was taken from the Department of Public Health Dentistry, Uttaranchal Dental and Medical Research Institute, Dehradun.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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