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 Table of Contents  
ORIGINAL RESEARCH
Year : 2018  |  Volume : 10  |  Issue : 3  |  Page : 115-120

Oral health-related quality of life and the index of orthodontic treatment need to evaluate the association of patients' self-perceived need and normative need toward orthodontic treatment


1 Department of Oral Pathology, Faculty of Dentistry, Melaka-Manipal Medical College, Malaysia
2 Department of Orthodontics, Faculty of Dentistry, Melaka-Manipal Medical College, Malaysia
3 Department of Community Medicine, Melaka-Manipal Medical College, Melaka, Malaysia
4 Department of Oral Medicine and Radiology, Faculty of Dentistry, Melaka-Manipal Medical College, Malaysia

Date of Web Publication14-Jun-2018

Correspondence Address:
Dr. Renjith George
Department of Oral Pathology, Faculty of Dentistry, Melaka-Manipal Medical College, Melaka
Malaysia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jioh.jioh_64_18

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  Abstract 

Aims: To assess oral health-related quality of life (OHRQoL) in patients with malocclusion and to measure the association of OHRQoL with orthodontic treatment need. Materials and Methods: The study sample comprised 290 participants aged 13 to 30 years, attending orthodontic clinics at the Faculty of Dentistry, Melaka Manipal Medical College (MMMC). The participants were asked to complete the Oral Health Impact Profile-14 (OHIP-14), after which clinical examinations were conducted to assess normative orthodontic treatment needs using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN). Results: A total of 290 adolescent and young adults participated in this study. The mean overall score for OHIP-14 was 11.8(±8.0). There was no significant association of oral health related quality of life (OHRQoL) between different age groups, gender, ethnicities and education levels. There was no significant association between age, gender, ethnicity, education level and orthodontic treatment need. Also, there was no significant association of OHIP-14 score between no treatment need and little treatment need. However, OHIP-14 score was significantly higher in borderline treatment need compared to no treatment need (6.06, 95% CI 1.07, 11.04), little treatment need (3.95, 95% CI 1.75, 6.16) while high treatment need had significantly higher OHIP-14 score than borderline treatment need (7.13, 95% CI 3.46, 10.80). Conclusion: Malocclusion has a significant negative impact on OHRQoL. There is a significant association in mean overall OHIP score when comparing high orthodontic treatment needs and with no treatment needs. This study did not find any significant association in orthodontic treatment needs in relation to age groups, gender, ethnicities and education level.

Keywords: IOTN, malocclusion, OHIP-14, oral health related quality of life, orthodontic treatment


How to cite this article:
George R, Samson RS, Soe HH, Donald PM, Hui WL, Ling PK, Saseendran K. Oral health-related quality of life and the index of orthodontic treatment need to evaluate the association of patients' self-perceived need and normative need toward orthodontic treatment. J Int Oral Health 2018;10:115-20

How to cite this URL:
George R, Samson RS, Soe HH, Donald PM, Hui WL, Ling PK, Saseendran K. Oral health-related quality of life and the index of orthodontic treatment need to evaluate the association of patients' self-perceived need and normative need toward orthodontic treatment. J Int Oral Health [serial online] 2018 [cited 2023 Jun 4];10:115-20. Available from: https://www.jioh.org/text.asp?2018/10/3/115/234521


  Introduction Top


The idea of oral health-related quality of life (OHRQoL) relates to the effect of oral well-being or illness on a person's daily routine, well-being, or overall satisfaction of life. This includes malocclusion, which has an impact not just on physical and economical satisfaction but can also affect quality of life by impairing the functions, outlooks, mutual relationships, socializing, self-confidence, and mental health.[1] The whole motive of performing a research on physical, social, and psychological significance of malocclusion on OHRQoL is that it enables to provide discernment on a person's impact on malocclusion and how it could possibly demand for orthodontic treatment. Therefore, OHRQoL may be thought out to be the best tool to assess whether a person needs orthodontic treatment or not and to evaluate its outcome.[2]

Malocclusion digresses from the majority of medical and dental conditions in that it is “a set of dental conditions” rather than a disease, and orthodontic treatment does not cure a condition but rather amend variations within the existing condition. This has led to debate about defining the point at which the extent of variation means that orthodontic treatment is desirable.[3] It has been suggested that the majority of oral health measures created in dentistry are not material to orthodontic patients in light of the fact that most malocclusions are asymptomatic, which is identified as esthetically compromised rather than loss of function. Furthermore, the affected individual and their knowledge can see a malocclusion distinctively, and perception regarding their malocclusion may not be related to the existing severity. Consequently, when evaluating the impact of a malocclusion, it is critical to include the factors in a broad category that can imply on their perception on malocclusion. A few individuals with a serious malocclusion are happy with or are not bothered with their esthetics though others are worried even with some minor irregularities.[4],[5]

The demand on orthodontic treatment in dental clinics is evaluated using certain measures, for example, the index of orthodontic treatment need (IOTN). However, there is evidence that many adolescents with normative orthodontic treatment need evaluated using IOTN encounter no impacts on their OHRQoL.[1] Nevertheless, the assessment of IOTN alone to identify orthodontic treatment need might be cumbersome since a few patients who have no psychosocial requirement for the treatment would be seen as requiring treatment. Therefore, utilization of OHRQoL along with IOTN will provide a possibly valuable correlation. Oral health impact profile-14 (OHIP-14) can be utilized as a potential intermediary measure to evaluate their perceived oral health for deciding treatment.[1],[3],[6]

IOTN helps determine those who need orthodontic treatment to improve their dental health rather than cosmetic concerns. OHRQoL should be a part of the evaluation of oral health because clinical indicators such as IOTN cannot describe the satisfaction of patients' seeking treatment.[7],[8] While assessing the normative and perceived treatment needs, instead of dental health component (DHC) and esthetic component of IOTN, DHC and OHRQoL, respectively, can be considered. Considering the subjectivity of esthetic component of IOTN, replacing it with more objective OHRQoL will be legible.[9]

Past research investigating the correlation between malocclusions and OHRQoL, and in addition, the effect of orthodontic treatment on OHRQOL has been ambiguous. A few researchers found a solid correlation between malocclusion or orthodontic treatment need [10],[11] and OHRQoL, yet others mentioned that there is no significant association.[12],[13] This study is carried out to assess OHRQoL in young individuals aged ranging from 13 to 30 years who demanded for orthodontic treatment in the dental faculty of Melaka-Manipal Medical College (MMMC).


  Materials and Methods Top


A prospective study was carried after obtaining ethical approval from the Research Ethics Committee (Reference Number: MMMC/FOD/AR/B5/E C-2017) of the Faculty of Dentistry at MMMC, Melaka, Malaysia, over a time span of 9 months (March–December 2017). Participants in this study were adolescents and adults aged 13–30 years, attending the Orthodontic Clinic, Faculty of Dentistry, MMMC. The patients who requested for orthodontic treatment were included in this study. The participants were recruited at their first visit for orthodontic screening before starting treatment. Participants were informed about the nature of the study and the examination procedures and were assured of the confidentiality of the collected information. Participants with good general health were included in the study. Exclusion criteria were participants who required a surgical intervention, had chronic medical conditions, had completed orthodontic treatment, and had severe dental facial anomalies such as cleft lip and palate. This was to prevent possible confounding effects of these conditions on the participants' quality of life. All participants signed informed consent. The data collected included sociodemographic data (age, gender, ethnicity, and education level), IOTN, and OHIP-14. The participants were assessed with a questionnaire and a clinical evaluation of IOTN for the normative needs for orthodontic treatment. After screening, the sample comprised 290 patients (131 males and 159 females).

Outcome variable (oral health impact profile-14)

OHRQoL was measured using validated English and Malay language-translated version of the OHIP-14. It has been shown that the OHIP-14 has good reliability, validity, and precision.[4],[5] It is a self-reported questionnaire scored on a 5-point Likert scale that targets on the concerns one may have of their oral health status on their quality of life. The concerns are categorized as seven dimensions, namely functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and handicap. The responses are rated as follows: never = score 0, hardly ever = score 1, occasionally = score 2, fairly often = score 3, and very often or every day = score 4. The OHIP-14 scores can range from 0 to 56, which is calculated by summing the ordinal values for the 14 items. Domain scores can range from 0 to 8. Higher OHIP-14 scores indicate worse OHRQoL, and lower OHIP-14 scores indicate better OHRQoL. All participants were requested to complete the OHIP-14 questionnaires before any orthodontic treatment.

Index of orthodontic treatment need – Dental health component

On completion of OHIP-14, clinical examinations were conducted to assess normative orthodontic treatment needs using the DHC of the IOTN. There are five main traits for DHC in IOTN which are missing teeth, overjet, cross-bite, displacement of contact points, and overbite.[4],[5] Only the highest scoring trait was used to assess the treatment need. The treatment needs of the patients were categorized as Grade 1 (no treatment need), Grade 2 (little treatment need), Grade 3 (borderline need), and Grade 4 and 5 (high treatment need).

Statistical analysis

Microsoft Excel 2013 was used for data entry and SPSS version 12 (SPSS Inc, Chicago, IL, USA) for data analysis. Descriptive statistics such as mean, standard deviation, and range for quantitative variables and frequency and percentage for categorical variables were calculated. Independent t-test and one-way ANOVA were performed to determine OHIP-14 score between different age groups, gender, ethnicities, and education levels. Chi-square test was performed to determine the association between age, gender, ethnicity, level of education, and orthodontic treatment need. One-way ANOVA and post hoc analysis were used to determine the association between the OHIP-14 and the orthodontic treatment need (IOTN), and finally, multiple linear regression was done to find the relationship between orthodontic treatment need and OHIP-14 after adjusting other covariates. All statistical tests were two-sided and the level of significance was set at 0.05.


  Results Top


A total of 290 adolescents and young adults participated in this study. [Table 1] shows that 29 (10%) participants were aged between 13 and 17 years and 261 (90%) were aged 18 years and above. Male and female participants were 131 (45.2%) and 159 (54.9%), respectively. The corresponding participants for Malay, Chinese, Indian, and other ethnicities were 103 (35.5%), 121 (41.7%), 57 (19.7%), and 9 (3.1%), respectively. On the other hand, participants with primary education level were 2 (0.7%), secondary education level were 68 (23.5), and tertiary education level were 220 (75.9).
Table 1: Sociodemographic characteristics of the participants (n=290)

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[Table 2] shows the IOTN grades for the participants, of which 23 (7.9%) of them belonged to Grade 1 (no treatment needed), 124 (42.8%) in Grade 2 (little treatment need), 93 (32.1%) in Grade 3 (borderline treatment need), and 50 (17.2%) in Grade 4 (high treatment need).
Table 2: Orthodontic treatment need by measuring the index of orthodontic treatment need score among patients attending orthodontic clinic of Melaka-Manipal Medical College (n=290)

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The mean overall score for OHIP-14 was 11.8 (±8.0) as shown in [Table 3]. Among all the seven domains of OHIP-14, handicap (1.1 [±1.4]) and social disability (1.1 [±1.6]) domains had the least impact of malocclusion on the OHRQoL. However, psychological discomfort had the highest impact with a mean of 2.8 (±2.0).
Table 3: Oral health-related quality of life among patients attending orthodontic clinic of Melaka-Manipal Medical College (n=290)

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[Table 4] shows the OHRQoL in relation to gender, age, ethnicity, and education level. There was no significant difference of OHRQoL between different age groups, gender, ethnicities, and education levels.
Table 4: Oral health-related quality of life in relation to gender, age, ethnicity, and education level among patients attending the orthodontic clinic, Melaka-Manipal Medical College

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[Table 5] shows the association between age, gender, ethnicity, education level, and orthodontic treatment need. There was no significant association between age, gender, ethnicity, education level, and orthodontic treatment need.
Table 5: Association between age, gender, ethnicity, education level, and orthodontic treatment need among patients attending the orthodontic clinic, Melaka-Manipal Medical College

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[Table 6] and [Table 7] show the association between the OHIP-14 and the orthodontic treatment need using post hoc analysis. The assumption of homogeneity of variances was violated as assessed by Levene's test for equality of variances (P = 0.001). The OHIP-14 score had statistically significant difference for different groups of orthodontic treatment needs, Welch's F (3, 77.89) = 36.72, P < 0.001. The mean OHIP-14 score had a gradual increase from no treatment need group (6.7 ± 8.2) to little treatment need (8.8 ± 6.0), borderline treatment need (12.8 ± 6.3), and high treatment need group (19.9 ± 8.7). Games-Howell post hoc analysis revealed that there was no significant difference of OHIP-14 score between no treatment need and little treatment need. However, OHIP-14 score was significantly higher in borderline treatment need compared to no treatment need (6.06, 95% confidence interval [CI] 1.07, 11.04) and little treatment need (3.95, 95% CI 1.75, 6.16), while high treatment need had significantly higher OHIP-14 score than borderline treatment need (7.13, 95% CI 3.46, 10.80).
Table 6: Association between the oral health impact profile-14 and the index of orthodontic treatment need

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Table 7: Post hoc analysis of Oral Health Impact Profile-14 and Index of Orthodontic Treatment Need

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Multiple linear regression was done, and model fit was assessed. The results showed that there were linearity, independence of residuals, homoscedasticity, no evidence of multicollinearity, and the assumption of normality being met. The multiple linear regression model was statistically significant with F (10, 279) = 11.927, P < 0.001, and R2 for the overall model was 29.9% with an adjusted R2 of 27.4%. There was no significant difference of OHIP-14 score between little and no treatment need; however, borderline treatment need (b = 6.19, 95% CI 3.06, 9.32) and high treatment need (b = 13.38, 95% CI 9.96, 16.80) had significantly higher OHIP-14 score compared to no treatment need as shown in [Table 8].
Table 8: Multiple linear regression analysis of association between orthodontic treatment need and oral health-related quality of life

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  Discussion Top


This cross-sectional study was conducted among individuals ranging from 13 to 30 years of age who wished to undergo orthodontic treatment to the dental clinic of Faculty of Dentistry, MMMC, to assess the quality of life using the OHIP-14 in subjects.

Majority of the participants in this study were females (54.9%) compared to males, which agreed to the previous studies done by Feu et al.[1] and Locker et al.[12] This shows that females tend to be unhappy with their dental appearance and are more self-conscious.[14],[15] About 90% of the participants were above the age of 18 years, and 270 participants out of 290 had tertiary level of education, which explains the fact that self-awareness and self-esteem increase with education.[16],[17]

OHIP-14 was mainly developed for people of older age category, but it has been found to be useful in assessing quality of life for orthodontic needs by many authors such as Masood et al.,[16],[18] Navabi et al.,[19] and Bernabé et al.[20] Hence, it was used to assess the malocclusion-related OHRQoL in the current study. Among the 290 participants, only 50 (17.2%) of them needed orthodontic treatment (Grade 4 and 5) after performing IOTN and all these participants had higher score of OHIP-14 compared to the ones not requiring orthodontic treatment. Studies done by Dimberg et al.,[21] Choi et al.,[22] and Simões et al.[23] showed that severe malocclusion can have deteriorating effect on the OHRQoL. The current study also showed that malocclusion affected some domains of OHRQoL such as psychologic discomfort (2.8 ± 2) and physical pain (1.9 ± 1.6), which was in line with the studies done by Masood et al.[16],[18] and Chen et al.[24]

Participants above the age of 18 years and with tertiary level of education had higher OHIP-14 score compared to the ones below 18 years with primary or secondary education. Since this study was done in Melaka, Malaysia, OHIP-14 scores of three main ethnic groups such as Malay, Chinese, and Indian were also studied and the values were almost close to 12.

The mean OHIP-14 score had a gradual increase from no treatment need group (6.7 ± 8.2) to little treatment need (8.8 ± 6.0), borderline treatment need (12.8 ± 6.3), and high treatment need group (19.9 ± 8.7). This proves that there is a definite negative impact on OHRQoL with respect to malocclusion.[25] Although this value is way lesser than the highest achievable score of OHIP-14 which is 56, the dental care provider must be cautious while treating such patients since their main concern toward orthodontic treatment may be to enhance their esthetics rather than improving their oral function and health.[1],[26],[27] Therefore, the use of OHIP-14 can be a very useful tool to provide information on the priorities which the patient may have toward treatment to deliver maximum patient satisfaction.


  Conclusion Top


Malocclusion has significant negative impact on OHRQoL. There is a significant association between mean overall OHIP score and high orthodontic treatment need (Grade 4 and 5) and no treatment need (Grade 1). This study did not find any significant association in orthodontic treatment needs in relation to age groups, gender, ethnicities, and education level.

Acknowledgment

We acknowledge Prof. Dr. Abdul Rashid Hj Ismail, Dean of the institution for his kind guidance and support throughout the study, Assoc. Prof. Dr. Priti Mulimani, Head of the department of Orthodontics and the research committee of Faculty of Dentistry, Melaka-Manipal Medical College for their contribution.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]


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