|Year : 2022 | Volume
| Issue : 2 | Page : 67-73
Oral health-related quality of life of visually impaired children aged 7–18 years
Fitri Diah Oktadewi1, Indah Titien Soeprihati2, Lisdrianto Hanindriyo3
1 Preventive Dentistry and Promotive of Dental Health Study Program, Faculty of Dentistry, Gadjah Mada University, Yogyakarta, Indonesia
2 Department of Pediatric Dentistry, Faculty of Dentistry, Gadjah Mada University, Yogyakarta, Indonesia
3 Department of Preventive and Community Dentistry, Faculty of Dentistry, Gadjah Mada University, Yogyakarta, Indonesia
|Date of Submission||18-Feb-2022|
|Date of Decision||24-Apr-2022|
|Date of Acceptance||30-Apr-2022|
|Date of Web Publication||12-Jul-2022|
Fitri Diah Oktadewi
Dental Medicine Study Program, Faculty of Medicine, Jenderal Soedirman University, Jl Dr. Soeparno, Purwokerto Utara, Jawa Tengah 53122
Source of Support: None, Conflict of Interest: None
Background: Only few studies have examined the impact of dental health on the quality of life of visually impaired children. Objective: The purpose of this study was to assess the relationships between oral health outcomes, socio-economic status, and oral health-related quality of life (OHRQoL) in visually impaired children aged 7–18 years. Methods: This study was conducted in special schools in Yogyakarta and Central Java Province. This study involved 70 visually impaired schoolchildren (aged 7–18 years; boys, 55.7% and girls, 44.3%). To investigate the oral health outcomes of caries, oral hygiene, and dental trauma, the Decayed, Missing, and Filled Permanent/Primary Teeth (DMFT/dmft) Index, Oral Hygiene Index-Simplified (OHI-S), and Traumatic Dental Injury Index were used. The Child Oral Health Impact Profile-Short Form 19 questionnaire was used to determine OHRQoL. Results: The mean DMFT Index and OHI-S scores were 4.8 ± 2.743 and 1.94 ± 0.84, respectively. Of the respondents, 22.9% had dental trauma. The Spearman correlation test showed no correlations between the mean OHRQoL score and DMFT/dmft score, no correlations between the mean OHRQoL and dental trauma, and no correlations between the mean OHRQoL and socio-economic status (P = 0.672, P = 0.551, and P = 0.465, respectively). The OHI-S score correlated with the OHRQoL score for the socio-emotional well-being domain (P = 0.031, r=−0.258). Conclusion: In the visually impaired children in this study, poor oral hygiene resulted in decreased OHRQoL. However, oral hygiene showed no significant relationships with dental trauma and socio-economic level, and caries showed no significant relationships with dental trauma and OHRQoL in these children.
Keywords: Caries, OHRQoL, oral health, socioeconomic, visually impaired
|How to cite this article:|
Oktadewi FD, Soeprihati IT, Hanindriyo L. Oral health-related quality of life of visually impaired children aged 7–18 years. Sci Dent J 2022;6:67-73
|How to cite this URL:|
Oktadewi FD, Soeprihati IT, Hanindriyo L. Oral health-related quality of life of visually impaired children aged 7–18 years. Sci Dent J [serial online] 2022 [cited 2022 Aug 20];6:67-73. Available from: https://www.scidentj.com/text.asp?2022/6/2/67/350756
| Background|| |
Visually impaired children are among those with special needs. Visual impairment is divided into complete blindness and low vision. Visually impaired children have poorer oral health than those with normal vision. Previous research has indicated that visually impaired children had generally poor oral hygiene, with a sufficiently high prevalence of caries.,, Shewale et al. reported that visually impaired children could not visualize plaques on tooth surfaces, which result in poor oral hygiene maintenance and increased caries. Shetty et al. suggested that this may be related to visually impaired children’s decreased capacity to maintain oral hygiene as a result of a lack of motor-visual coordination. Without the supervision of their parents, most of these children brush their teeth only once a day. Another contributing factor may be these children’s lack of concern for their physical appearance.
Owing to their poor vision, visually impaired children also have a poor sense of orientation, which affects their ability to determine directions and locomotor abilities, resulting in a high prevalence of dental trauma and increased risk of general trauma,, which in turn results from the decreasing orientation related to directions and their abilities. Children’s diverse oral health problems are directly related to annoyance and tooth pain, which ultimately affect children’s and their parents’ and families’ QoL., Oral health-related quality of life (OHRQoL) showed individual differences in terms of how each individual deals with their physical, psychological, and social functions in their daily lives, which affects their dental health statuses. The study showed that oral health condition was frequently related to socio-economic status, which may influence OHRQoL. The families of children with disabilities frequently have higher living costs for health treatment. They also experience other problems such as reduced working hours or quitting a job to take care of their family members with disabilities. Nursing care for children with disabilities, such as visually impaired children, requires three times higher cost than that for healthy children.
Previous research has established links among socio-economic level, oral health outcomes, and OHRQoL., The existing disparities in socioeconomic status have a detrimental effect on OHRQoL. Research on the OHRQoL of healthy children has advanced significantly, whereas that in children with specific needs, such as visually impaired children, remains severely constrained. Tagelsir et al. and Singh et al. conducted separate studies on visually impaired children using the Child-Oral Impact on Daily Performance questionnaire as their research instrument. Tagelsir et al. reported that the OHRQoL of visually impaired children had no significant relationship with their oral health statuses in terms of, for example, caries experience, Oral Hygiene Index-Simplified (OHI-S) score, and dental trauma. Singh et al. reported contradicting findings, claiming that strong relationships exist between caries exposure and dental trauma and the oral cavity health of visually impaired children. Those discrepancies in findings undoubtedly necessitate more investigations in comparable research subjects. The purpose of this study was to determine whether oral health outcomes are associated with parental socio-economic level and OHRQoL in visually impaired children.
| Materials and Methods|| |
Research design and population
This observational research was conducted using a cross-sectional research design from February to March 2020, with ethical approval from the Research Ethics Committee of the Faculty of Dentistry, Universitas Gadjah Mada (No. 00351/KKEP/FKG-UGM/EC/2020). The study population was composed of 127 visually impaired schoolchildren aged 7–18 years in Yogyakarta and Klaten. Data were obtained from the Department of Education, Youth, and Sports and Ministry of Religion of Yogyakarta in 2019. However, data from the research respondents, which comprised 70 visually impaired children from Yogyakarta City, Sleman, Bantul, and Klaten Regency, were collected using a purposive sampling method. The number of respondents was calculated using the formula of minimum samples for health research by considering the coefficient between the variables used in a previous study. The inclusion criteria for this research were as follows: visually impaired children (1) studying in special or inclusion schools, (2) with complete blindness or poor vision, (3) aged 7–18 years old, (4) living with their parents or families, and (5) with the consent of their parents to be involved in this research. The exclusion criteria were as follows: children (1) with mental retardation, (2) with other disabilities, (3) living in a special dormitory or orphanage, and (4) who were not cooperative. All respondents involved have obtained consent from parents.
Measurement and data analysis
The measurement consisted of three components: oral examination, parents’ socio-economic questionnaire, and the OHRQoL questionnaire. The oral examination was performed at the respondent’s school in 2 weeks. The respondents were examined by one examiner (the main researcher) assisted by a recorder (a dentist). The examination was conducted under adequate lighting from a headlamp. Infection control and waste disposal recommendations were followed up in accordance with the examination protocol. Once the examination was completed, the respondent was interviewed to assess OHRQoL. Parents’ socio-economic status questionnaire and informed consent form were sent and completed by the children’s parents before the examination.
Dental caries, oral hygiene status, and dental trauma were all assessed as oral health outcomes for the visually impaired children in this study. Dental caries was quantified using the Decayed, Missing, and Filled Permanent/Primary Teeth (DMFT/dmft) Index, and the following criteria were applied: (1) D/d = decayed tooth, tooth with cavity due to dental caries, or deterioration of restored tooth due to caries; (2) M/m = missing or removed tooth due to dental caries; and (3) F/f = filling or filled tooth due to caries that is in good condition. The DMFT/dmft Index was calculated by adding each component (D, M, and F, and d, m, and f) of deciduous teeth. The examination for caries was performed using a mouth mirror and an explorer with adequate lighting.
The OHI-S was used to assess oral hygiene. It comprised a combination of the debris and calculus indexes of the six selected tooth surfaces. The explorer was used to determine the amount of debris and calculus on the tooth surface. The surface area covered by debris was estimated by running the explorer’s side along the tooth surface being studied. The explorer was transferred from the incisal/occlusal to the gingival border. The amount of occlusal or incisal material was recorded after removal. By using the same explorer, the surface area covered by the subgingival and supragingival calculi was calculated. The OHI-S score was determined by multiplying the debris and calculus scores by the number of teeth examined. The OHI-S score ranges from 0 to 6.
Dental trauma was evaluated using the modified traumatic dental injury classification system of the World Health Organization. The criteria for tooth trauma of the anterior tooth were as follows: (1) tooth treated for dental trauma (treated injury); (2) trauma resulting in enamel fracture; (3) trauma resulting in enamel fracture to the dentin; (4) trauma resulting in damaged pulp; and/or (5) missing tooth caused by trauma. The dental trauma score was calculated in this study by adding the number of teeth with trauma.
Socio-economic status was determined using the questionnaire completed by the children’s parents. The questionnaire consisted of 10 question items covering parents’ education, parents’ occupation, family income, household expenses, and ownership of valuable properties such as houses, vehicles, and the number of family dependents. The response to each question was assigned a score of 1–4, with total scores ranging from 10 to 40. Parents’ socio-economic status was classified into three categories based on the obtained mean value and standard deviation as follows: high (≥30), average (20–29), and low (<20).
OHRQoL was measured using the Indonesian version of the Child Oral Health Impact Profile-Short Form 19 (COHIP-SF-19) questionnaire, which consists of 19 questions classified into three domains: oral health (5 items), functional well-being (4 items), and socio-emotional well-being (10 items). The validity test of the COHIP-SF-19 questionnaire was performed in 30 respondents and resulted in 13 valid question items with an alpha Cronbach value of 0.8013.
The answer to each question corresponded to five scoring criteria based on a Likert scale: never (5 points), almost never (4 points), sometimes (3 points), fairly often (2 points), and almost all the time (1 point). One question had a reversed scoring criterion [question no. 13 in [Table 1]]. The final OHRQoL score ranged from 13 to 65 points. The higher the final OHRQoL score, the better the respondent’s OHRQoL. The Spearman correlation test was used to analyze the data in this study.
|Table 1: Frequency distribution of the responses to the COHIP-SF-19 Questionnaire|
Click here to view
| Results|| |
[Table 2] shows the respondents’ characteristics, including age, sex, visual impairment type, parents’ socio-economic status, oral hygiene index, and presence of caries. In general, most respondents came from families with average socio-economic statuses (67.1%), categorized as having average oral hygiene (67.1%). The prevalence rate of dental trauma was 77.1%.
[Table 1] shows the frequency distribution of the responses to the questions in the COHIP-SF-19 questionnaire. Most respondents never experienced disturbances to oral health and functional and socio-emotional well-being due to oral cavity conditions, as demonstrated in most respondents’ answer of “Never” to the question items in each questionnaire domain. The positive question in the socio-emotional wellbeing domain related to self-confidence and oral health outcomes obtained a positive response of “Fairly often” from 40% of the respondents. After intense scrutiny, some questions were found to possibly require the respondents’ evaluation based on their visual ability, covering questions 2 (related to the oral health domain) and 7, 8, 9, 10, 11, and 13 (related to the socio-emotional well-being domain).
The Spearman test was used to examine the relationship between oral health outcomes and parents’ socio-economic level [Table 3]. The findings indicate a significant negative relationship between the presence of caries in visually impaired children and their parents’ socio-economic status.
|Table 3: Results of the Spearman correlation test between oral health outcomes and socio-economic status|
Click here to view
The relationship between oral health outcomes and OHRQoL in visually impaired children is shown in [Table 4]. The findings indicate a strong negative relationship between oral hygiene and OHRQoL in terms of socio-emotional well-being.
|Table 4: Results of the Spearman correlation test between oral health outcomes and OHRQoL, and between socioeconomic status and OHRQoL|
Click here to view
| Discussion|| |
A correlation between oral hygiene and OHRQoL was found in the visually impaired children in this study. Worse oral hygiene and OHRQoL in the socio-emotional well-being domain were characterized by the following conditions: felt anxious, looked different, felt sad, lacked self-confidence, and bullied by friends, with the addition of even lost concentration in school due to oral health outcomes [Table 1]. The worse impacts of poor oral hygiene, such as bad breath and bleeding gums, can influence someone’s social and psychological aspects, resulting in reduced self-confidence and self-esteem, anxiety to socialize with others, feeling shy, and so forth., The inability of the visually impaired children to visualize plaques on teeth surfaces resulted in poor oral hygiene, which progressed to caries formation. The other factors were due to poor hand–eye coordination during toothbrushing and poor attention to physical appearance among visually impaired children. The toothbrushing training method implemented to sighted children generally uses visual perception by applying a disclosing agent to show dental plaques. This could not be applied to visually impaired children. The other difficulties related to plaque control include placing the toothpaste on the toothbrush and less appropriate toothbrushing techniques. Previous research has reported that of visually impaired children, 77% brushed their teeth without supervision and 60.5% had never visited a dentist.
In contrast, the dental caries and dental trauma experienced by visually impaired children do not correlate with their OHRQoL owing to several possibilities. Visually impaired children could not realize and detect the initial signs of oral cavity diseases such as caries, which hindered their prevention and treatment. The limited vision of visually impaired children decreases their attention and awareness of their performance. The COHIP-SF-19 questionnaire used in this research contained question items requiring the respondents’ evaluation by depending on their visual ability, resulting in their unfair judgment of the questionnaire. Individuals with limited visions showed limited facial expressions to the stimulus. This could result in lower response scores to the indicator of OHRQoL directly associated with physical performance. These findings confirm the suggestion of Tagelsir et al. to develop a questionnaire for the assessment of the OHRQoL of children with special needs, because none of the existing OHRQoL questionnaires has considered children with disabilities. The use of the DMFT/dmft index in this research might be the reason why no relationship was found between the presence of caries and OHRQoL. The DMFT/dmft index is limited in that it does not describe the severity or consequence of poorly treated caries, which can influence health in general and OHRQoL. As recognized, severe and untreated caries can affect children’s QoL, starting from feeling pain, inconvenience, unpleasant appearance, eating and sleeping disorders, and so forth.
Dental trauma was a severe problem experienced by the visually impaired children in this study. Although the prevalence of dental trauma is relatively high, this condition is still neglected. The prevalence rate of dental trauma among the visually impaired children in this study was 22.9%, close to those in previous studies, which ranged from 19% to 34.95%.,, The decreasing direction orientation and mobility abilities due to poor vision led to dental trauma in the visually impaired children., Poor visualization was the main factor that caused the high prevalence rate of dental fracture caused by trauma among the visually impaired children. However, owing to poor support, the children’s risk of dental collision or trauma during various activities increased. The dental trauma evaluation in this research was conducted on the anterior teeth, which, like those on the upper jaw, were considered to be the most frequently affected by trauma (90%) because of their position and less protection compared with the others. The anterior teeth, especially the incisors, play essential roles in dental functions such as esthetic, phonation, psychological aspects, and functional activities.
Socio-economic status showed no relationship with OHRQoL in the visually impaired children, possibly because of the other factors that might have had greater influences on the research results. The OHRQoL of the visually impaired children was also influenced by other prominent factors such as family relationship or support, self-maintaining pattern, social interactions, neighborhood, dependency, mental condition, and cultural status.,, These factors were not assessed in this study. Socio-economic level may influence an individual’s oral cavity condition. The findings of this study established a statistically significant negative correlation between the presence of caries and socio-economic level. This suggests that the higher the socioeconomic class of parents, the lower the incidence rate of caries in their visually impaired children and vice versa. Socio-economic variables such as income, educational level, and family composition all had effects on the prevalence of caries., The socio-economic level was a contextual factor that played an essential role in the evaluation of OHRQoL and influenced access to dental and oral health treatments.
The limitation of this research was that the respondents’ age range was still quite extensive, from 7 to18 years. It might have resulted in disparities in oral health knowledge and motor skills for dental health maintenance, hence impacting the research outcomes. In addition, this research did not include the characteristics of visually impaired children, such as type of blindness, the age at which they became blind, or their parents’ or caregivers’ involvement. It also requires the development of a measurement instrument for OHRQoL in visually impaired children by considering their characteristics in future research.
| Conclusion|| |
In conclusion, this research suggests that poor oral hygiene results in decreased OHRQoL in visually impaired children. However, oral hygiene showed no significant relationship with dental trauma and socio-economic level in the visually impaired children in this study, and caries showed no significant relationship with dental trauma and OHRQoL. Thus, oral health promotion and prevention should be emphasized as critical components of the QoL of visually impaired children. Furthermore, these findings showed the importance of developing an assessment tool for the OHRQoL of visually impaired children by considering their characteristics.
The authors would like to thank the respondent participants, school representatives, and participants’ parents for their assistance and participation in this study.
Financial support and sponsorship
This study was undertaken with funding support from the Faculty of Medicine, Jenderal Soedirman University.
Conflicts of interest
The authors have no conflicts of interest to declare.
| References|| |
Pascolini D, Mariotti SP. Global estimates of visual impairment: 2010. Br J Ophthalmol 2012;96:614-8.
Prashanth ST, Bhatnagar S, Das UM, Gopu H. Oral health knowledge, practice, oral hygiene status, and dental caries prevalence among visually impaired children in Bangalore. J Indian Soc Pedod Prev Dent 2011;29:102-5.
] [Full text]
Parkar S, Patel N, Patel N, Zinzuwadia H. Dental health status of visually impaired individuals attending special school for blind in Ahmedabad city, India. Indian J Oral Sci 2014;5:73. [Full text]
Solanki J, Gupta S, Arora G, Bhateja S. Prevalence of dental caries and oral hygiene status among blind school children and normal children, Jodhpur City: A comparative study. J Adv Oral Res 2013;4:1-6.
Shewale A, Gattani D, Dhengar Y, Gudadhe B, Meshram S. Oral health status of visually disabled individuals attending blind schools in Nagpur city. Int J Appl Res 2017;3:224-6.
Shetty V, Hegde AM, Bhandary S, Rai K. Oral health status of the visually impaired children—A South Indian study. J Clin Pediatr Dent 2010;34:213-6.
Reddy K, Sharma A. Prevalence of oral health status in visually impaired children. J Indian Soc Pedod Prev Dent 2011;29:25-7.
] [Full text]
Bhat N, Agrawal A, Nagarajappa R, Roy SS, Singh K, Chaudhary H, et al
. Teeth fracture among visually impaired and sighted children of 12 and 15 years age groups of Udaipur city, India—A comparative study. Dent Traumatol 2011;27:389-92.
Debnath A, Srivastava BK, Shetty P, Eshwar S. New vision for improving the oral health education of visually impaired children—A non-randomized control trial. J Clin Diagnostic Res 2017;11:29-32.
Akhter R, Hassan NMM, Martin EF, Muhit M, Smithers-Sheedy H, Badawi N, et al
. Caries experience and oral health-related quality of life (OHRQoL) of children and adolescents with cerebral palsy in a low-resource setting. BMC Oral Health 2019;19:15.
Papaioannou W, Oulis CJ, Latsou D, Yfantopoulos J. Oral health-related quality of life of Greek adults: A cross-sectional study. Int J Dent 2011;12:146-50.
Kumar S, Kroon J, Lalloo R. A systematic review of the impact of parental socio-economic status and home environment characteristics on children’s oral health related quality of life. Health Qual Life Outcomes 2014;12:41.
Desriyani Y, Nurhidayah I, Adistie F. Burden of parents in children with disability at SLB Negeri Cileunyi. NurseLine J 2019;4:21-30.
Piovesan C, Abella C, Ardenghi TM. Child oral health-related quality of life and socioeconomic factors associated with traumatic dental injuries in schoolchildren. Oral Health Prev Dent 2011;9:405-11.
Paula JS, Leite ICG, Almeida AB, Ambrosano GM, Pereira AC, Mialhe FL. The influence of oral health conditions, socioeconomic status and home environment factors on schoolchildren’s self-perception of quality of life. Health Qual Life Outcomes 2016;10:1-8.
Bof de Andrade F, Drumond Andrade FC. Socioeconomic inequalities in oral health-related quality of life among Brazilians: A cross-sectional study. Dent J 2019;7:9.
Tagelsir A, Khogli AE, Nurelhuda NM. Oral health of visually impaired schoolchildren in Khartoum state, Sudan. BMC Oral Health 2013;13:33.
Singh A, Dhawan P, Gaurav V, Rastogi P, Singh S. Assessment of oral health-related quality of life in 9–15 year old children with visual impairment in Uttarakhand, India. Dent Res J (Isfahan) 2017;14:43-9.
World Health Organization. Oral Health Surveys: Basic Method. 5th ed. Geneva: World Health Organization; 2013. p. 42-3.
Liu HY, Chen CC, Hu WC, Tang RC, Chen CC, Tsai CC, et al
. The impact of dietary and tooth-brushing habits to dental caries of special school children with disability. Res Dev Disabil 2010;31:1160-9.
Marya CM. A Textbook of Public Health Dentistry. India: Jaypee Brothers Medical Publisher; 2011. p. 190-2.
Munot H, Avinash A, Kashyap N, Baranwal R, Kumar B, Sagar MK. Prevalence of traumatic dental injuries among visually impaired children attending special schools of Chhattisgarh. J Indian Soc Pedod Prev Dent 2017;35:209-15.
] [Full text]
Azwar S. Penyusunan Skala Psikologi Edisi 2 (The Development of Psychological Scale 2nd ed.). 2nd ed. Yogyakarta: Pustaka Pelajar; 2018.
Karamoy Y, Darwita RR, Maharani DA. Assessing oral health related quality of life among 12 years old aged children: Validation of COHIP-SF Indonesian Version. Cakaradonya Dent J 2014;6:678-744.
Azodo CC, Osazuwa-Peters N, Omili M. Psychological and social impact of halitosis: A review. J Soc Psychol Sci 2010;3:74.
Buunk-Werkhoven Y, Dijkstra-le Clercq M, Verheggen-Udding E, de Jong N, Spreen M. Halitosis and oral health-related quality of life: A case report. Int J Dent Hyg 2012;10:3-8.
Reddy JM, Ganapathy DM. Oral hygiene status among visually handicapped. Drug Invent Today 2019;11:1559-63.
Mohd-Dom TN, Omar R, Malik NA, Suiman K, Rahmat N. Self-reported oral hygiene practices and periodontal status of visually impaired adults. Glob J Heal Sci 2010;2:184-91.
Priyadarshini P, Pushpanjali K, Anitha S. Assessment of oral health status among visually impaired children. J Dent Oro-facial Res 2015;11:3-6.
Bolat N, Doğangün B, Yavuz M, Demir T, Kayaalp L. Depression and anxiety levels and self-concept characteristics of adolescents with congenital complete visual impairment. Turk Psikiyatri Derg 2011;22:77-82.
Ramazani N, Rezaei S. Evaluation of the prevalence of clinical consequences of untreated dental caries using PUFA/pufa index in a group of Iranian children. Iran J Pediatr 2017;27:e5016.
Leal SC, Bronkhorst EM, Fan M, Frencken JE. Untreated cavitated dentine lesions: Impact on children’s quality of life. Caries Res 2012;46:102-6.
Agrawal A, Bhatt N, Chaudhary H, Singh K, Mishra P, Asawa K Prevalence of anterior teeth fracture among visually impaired children, India. Int J Dent Clin 2013;24:664-8.
El-Kalla IH, Shalan HM, Bakr RA. Impact of dental trauma on quality of life among 11-14 years schoolchildren. Contemp Clin Dent 2017;8:538-44.
] [Full text]
Adigun K, Oluleye TS, Ladipo MM, Olowookere SA. Quality of life in patients with visual impairment in Ibadan: A clinical study in primary care. J Multidiscip Healthc 2014;7:173-8.
Kamelska AM, Mazurek K. The assessment of the quality of life in visually impaired people with different levels of physical activity. Phys Cult Sport Stud Research 2015;67:31-41.
Amedo AO, Adade S, Koomson NY, Osae EA. Influence of visual impairment on the quality of life: A survey of patients reporting at the low vision centre of the eastern regional hospital of Ghana. J Ophthalmic Sci 2016;1:1-13.
Sankeshwari RM, Ankola AV, Tangade PS, Hebbal MI. Association of socio-economic status and dietary habits with early childhood caries among 3- to 5-year-old children of Belgaum city. Eur Arch Paediatr Dent 2013;14:147-53.
Tanaka K, Miyake Y, Sasaki S, Hirota Y. Socioeconomic status and risk of dental caries in Japanese preschool children: The Osaka Maternal and Child Health Study. J Public Health Dent 2013;73:217-23.
Peter E, Baiju RM, Sreela LS, Varghese NO, Varughese JM. Does socioeconomic status and family type influence oral health-related quality of life in individuals with malocclusion? J Indian Orthod Soc 2018;52:89-93. [Full text]
[Table 1], [Table 2], [Table 3], [Table 4]