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ORIGINAL ARTICLE
Year : 2016  |  Volume : 14  |  Issue : 1  |  Page : 57-62

Assessment of the severity of malocclusion and orthodontic treatment needs among 16–24-year-old rural population of Dehradun, India: A cross-sectional study


1 Department of Public Health Dentistry, Uttaranchal Dental and Medical Research Institute, Dehradun, Uttarakhand, India
2 Department of Orthodontics and Dentofacial Orthopedics, Uttaranchal Dental and Medical Research Institute, Dehradun, Uttarakhand, India
3 Department of Orthodontics and Dentofacial Orthopedics, Maharishi Markandeshwar College of Dental Sciences and Research, Ambala, Haryana, India

Date of Web Publication15-Mar-2016

Correspondence Address:
Amit Rekhi
Department of Public Health Dentistry, Uttaranchal Dental and Medical Research Institute, Mazri Grant, Haridwar Road, Dehradun - 248 140, Uttarakhand
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2319-5932.178721

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  Abstract 

Introduction: Malocclusion is a developmental condition signifying a mal-relationship between the arches. It is classified into several types and manifest variably from person to person. Aim: To evaluate the severity of the malocclusion and orthodontic treatment needs in 16–24-year-old Indian young adults. Materials and Methods: A cross-sectional study was conducted among 660 subjects (352 males; 308 females) residing in rural areas of Dehradun, India. Clinical examinations were conducted using the dental esthetic index (DAI) to evaluate the extent of orthodontic treatment needs among the population. Results: The mean DAI score of the sample was found to be 31.08 ± 7.98. No gender-wise differences were found. Statistically significant differences were observed between the age groups. Diastema between males and females was the only component where differences were found to be statistically significant. Conclusion: Around 45.15% of the total sample had a highly desirable and mandatory orthodontic treatment need. Gender did not influence treatment need whereas age group was found to influence it.

Keywords: Dental aesthetic index, malocclusion, rural population, young adult


How to cite this article:
Rekhi A, Mehra A, Saini Y. Assessment of the severity of malocclusion and orthodontic treatment needs among 16–24-year-old rural population of Dehradun, India: A cross-sectional study. J Indian Assoc Public Health Dent 2016;14:57-62

How to cite this URL:
Rekhi A, Mehra A, Saini Y. Assessment of the severity of malocclusion and orthodontic treatment needs among 16–24-year-old rural population of Dehradun, India: A cross-sectional study. J Indian Assoc Public Health Dent [serial online] 2016 [cited 2020 Jan 21];14:57-62. Available from: http://www.jiaphd.org/text.asp?2016/14/1/57/178721


  Introduction Top


Malocclusion as a word literally means bad bite.[1] Malocclusion can be defined as an occlusion in which there is a mal-relationship between the arches in any of the planes or where there are anomalies in tooth position, number, form, and developmental position of teeth beyond normal limits.[2] Malocclusion is not a disease, but a developmental condition representing biological diversity. It is basically the clinically significant variations from normal morphology and range of growth. Malocclusion may be the result of a combination of minor variations from the normal and these combinations add on to produce a clinical problem.[3]

The factors responsible for malocclusion include genetic and environmental factors, or a combination of both along with various local factors such as adverse or deleterious oral habits [4] and anomalies in number, shape and developmental position of teeth and dentition. Malocclusion may affect periodontal health, causes dental caries and temporomandibular joint problems.[5]

Malocclusion is a chronic condition and therefore, treatment of malocclusion has been associated with a great degree of subjectivity and varied perceptions of treatment need.[3] Despite the inconsistent evidence regarding the affect of malocclusion on long-term psychosocial well-being, it has been observed that the facial features, including oral esthetics have a potential to influence self-perceived appearance,[6] especially during that phase of life involving intense social and affective interaction. For older adolescents and younger adults, physical attractiveness plays an important factor affecting social relationships and self-perception which in turn can affect the quality of life.[7],[8],[9]

Malocclusion ranks second among the common dental diseases in children and young adults, next to dental caries.[10] Developing countries like India face many challenges in rendering oral health care as the majority of the population resides in rural areas where oral health programs and preventive measures are far from satisfying needs.[11],[12] As there is a dearth of statistical data on malocclusions in this particular geographical area, this study was conducted to assess the severity of malocclusion and orthodontic treatment needs of 16–24-year-old adolescents and younger adults residing in the rural areas of Dehradun, India, using the dental aesthetic index (DAI).


  Materials and Methods Top


A cross-sectional study was carried out among 16–24-year-old subjects selected from a rural population of Dehradun, Uttarakhand, India. The study protocol was approved by the Institutional Ethical Committee and a voluntary informed consent was obtained from each participant before the study. This study was carried out from the month of February to May 2015.

A pilot study was conducted among 68 subjects from 2 villages to check the feasibility of the methodology planned and for sample size estimation. A sample size of 660 was calculated to be satisfactory to detect an odd's 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 (DAI < 30), a type I error of 5%, a statistical power of 80% and allowance of 10% refusal.

A two-stage stratified cluster sampling technique with villages as the primary sampling unit was utilized. All subjects between 16 and 24 years, willing to participate and giving their consent were selected. Subjects with any structural abnormality in the teeth concerned and those who were undergoing or had undergone any orthodontic treatment previously were excluded. All readings were recorded on a specially prepared form based on World Health Organization's (WHO) Oral Health Survey-Basic Methods (1997).[13] The form consisted of demographic variables such as identification number, name, age and gender along with the DAI for recording the severity of malocclusion and orthodontic treatment needs.

All measurements were performed by a single calibrated examiner. The intra-examiner test was performed in the measurement of the DAI (kappa values 0.82). The data were entered into the Excel sheet (Micro Soft Office 2007) and then analyzed using the Statistical Package for Social Sciences (SPSS) version 17.0, (IBM 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 orthodontic treatment needs as determined by DAI.


  Results Top


Of the 660 subjects examined, 352 (53.3%) were males and 308 (46.7%) were females [Table 1]. The mean DAI score of the sample was found to be 31.08 ± 7.98 (range: 17–66). For males, the mean DAI score was 31.09 ± 7.92 and for females, it was 31.06 ± 8.05. For age-wise comparisons, the subjects were divided into two groups; 16–18 years (n = 282) and above 18 years (n = 378). The age group of 16–18 years had a mean DAI score of 32.52 ± 8.51 as compared to 30 ± 7.39 for the age group of 18 years above.
Table 1: Distribution of study population according to age and gender

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No gender-wise differences were found (P = 0.836). However, when the age-wise differences were seen, statistically significant differences were observed between the age groups (P = 0.004) [Table 2].
Table 2: Gender-wise and age-wise distribution of subjects according to dental esthetic index scores

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When the gender-wise distribution of the subjects was done based on the different components of the DAI, it was seen that diastema between males and females was the only component where differences were found to be statistically significant (P = 0.003) [Table 3].
Table 3: Gender-wise distribution of subjects according to different dental esthetic index characteristics

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Among age groups, crowding, largest anterior maxillary irregularity, anterior maxillary overjet, vertical anterior open-bite and antero-posterior molar relation were found to have statistically significant differences (P< 0.05) [Table 4].
Table 4: Age-wise distribution of subjects according to different dental aesthetic index characteristics

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It was seen that only 28 (4.24%) subjects had more than one tooth missing and around 36.36% (n = 240) subjects had crowding in at least one of the arches. Spacing of 2 mm was seen in 11.21% (n = 74) subjects and diastema of more than 1 mm was seen in 26.97% (n = 178) subjects. The irregularity of more than 2 mm was seen 37.58% (n = 248) and 44.55% (n = 294) of the subjects in maxillary and mandibular arches, respectively. Where overjet (>2 mm) in the maxilla was seen in 434 (65.76%) of subjects, mandibular overjet (>1 mm) was seen in a negligible 2.14% (n = 14) subjects. Same was the case with open bite (more than 1 mm) where only 2.73% (n = 18) subjects showed this trait. Overall, around 48.18% (n = 318) subjects did not show a normal molar relation.


  Discussion Top


Malocclusion is the second most common of the dental diseases in children and young adults, next to dental caries in India.[10] The prevalence of malocclusion in India in similar age groups has been reported to vary from around 22% to 33%.[14] The urban-rural variations have not been widely compared. Several indices have been proposed in response to an external need for information on the prevalence of malocclusions and for methods to objectively quantify the severity of the various features of malocclusion.[15] These indices measure the severity of malocclusion; either as a deviation from normal/ideal occlusion or in terms of perceived treatment needs.[15] Even though there are various indices and measure available for assessing malocclusion, there has been no consensus as to which one is suitable to be used in a certain condition. Bellot-Arcís et al.[16] have stated that DAI and Index of Orthodontic Treatment Needs (IOTN) were more often used in cross-sectional studies where IOTN is used above all in child and adolescent populations, DAI is employed in the adolescent/adult group.

The DAI is a tool that helps identify treatment needs and prioritizes them according to objective and subjective aspects. Therefore, it allows better use of the limited resources available.[17],[18] The DAI was accepted by the WHO as an international cross-cultural index in the assessment of orthodontic treatment need and has been widely used since its development in 1986.[19]

The DAI establishes a list of occlusal traits or conditions which allow the observation of malocclusions based on their severity. This condition becomes reproducible and informs us about the population's orthodontic treatment needs.[20] It measures ten intraoral traits which are individually multiplied by a regression coefficient. These traits are: Missing visible teeth (incisor, canine, premolar), crowding in incisal segments (maxillary and mandibular), spacing in incisal segments (maxillary and mandibular), diastema, largest anterior maxillary irregularity, largest anterior mandibular irregularity, anterior maxillary overjet, anterior mandibular overjet, vertical anterior openbite and antero-posterior molar relationship. To calculate DAI score a formula has been used as: (Missing visible teeth × 6) + (crowding) + (spacing) + (diastema × 3) + (largest maxillary irregularity) + (largest mandibular irregularity) + (anterior maxillary overjet × 2) + (anterior mandibular overjet × 4) + (vertical anterior openbite × 4) + (antero-posterior molar relationship × 3) +13. According to resulting sum of the DAI score, the DAI scores were divided into the four categories based on their interpretation of severity of malocclusion. DAI scores of 25 and below represent normal or minor malocclusion with no treatment needed; 26–30 represent definite malocclusion with a treatment option considered elective; 31–35 represent severe malocclusion with treatment indicated as highly desirable; scores of 36 and higher represent very severe malocclusion with treatment considered mandatory.[13] This sample was selected considering the fact that 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 presence of lesser physiological wear, wasting diseases, and periodontal diseases in the teeth of such individuals positively affects the accuracy of the method.

The mean DAI score found in this study was 31.08 ± 7.98 which was higher than those found in studies by Baca-Garcia et al.[21] and Bernabé and Flores-Mir [17] in similar samples. A higher mean DAI score noticed among the study subjects might be attributed to the fact that this study was conducted in a rural area where differences in the type of food and nutritional status, lack of awareness about oral hygiene and unchecked oral habits exist as compared to an urban setup.[22],[23] The type of food and malnutrition may lead to disruptive eruptive patterns of teeth and inadequate development of oral structures. Furthermore, the tooth structure may be hypoplastic and hence more susceptible to dental caries. These factors may thus contribute in the development of malocclusion.[22]

When gender-wise comparisons were done, males showed higher orthodontic treatment needs but no statistically significant differences were observed, while studies conducted by Oshagh et al.,[24] Onyeaso and Arowojolu,[25] Baca-Garcia et al.[21] and Bernabé and Flores-Mir [17] found a significant difference by sex.[26] When the sample was divided into two age groups (16–18 years; above 18 years) and analyzed, significant differences were observed in the orthodontic treatment need.

This study found a low frequency (4.2%) of individuals with at least one missing tooth. This was similar to studies conducted in Spanish [21] (3.7%) and Nigerian [27] populations (3.5%). Crowding in incisal segments in at least one arch was reported in 36.4% of the subjects which was quite similar to those reported in a study on Nigerians [25] (33.6%) but was much less as compared to a Spanish [21] (76.3%) and a Peruvian population [17] (90.6%). The prevalence of midline diastema (27%), in this study, was higher to that reported in earlier studies by Nainani and Relan [28] (9.86%), Kaur et al.[12] (15.65%) but lesser than adolescents of Ibadan, Nigeria [25] (37%).

The frequency of the sample with largest anterior irregularity >2 mm in both the maxillary and mandibular arches was found to be 37.58% and 44.55%, respectively. This was found to be higher as compared to studies carried out in Peruvian population (24% and 36.7%),[17] Spanish population (22.4% and 35.1%)[21] and Nigerian population (17.2% and 22.4%).[27] Age wise comparisons between the two groups showed a statistically significant difference in case of both crowding in arches and irregularity in the maxilla. Jenny et al.[29] have suggested that inheritance differences in tooth size and arch size may be one reason for differences in DAI scores because the DAI includes measurements of the most relevant orthodontic traits that affect dental esthetics, such as crowding. The antero-posterior molar relationships showed that 48.2% subjects did not have a normal cuspal relation, which were similar to Peruvian [17] (52.1%) and Spanish [21] young adults (43.3%) but much higher than Nigerians [27] (16.2%).

Gender-wise differences were found to be significant for only the midline diastema where the rest of the traits had no significant relations. A study conducted by Shivakumar et al.[30] in an Indian population had also found significant differences in the case of midline diastema and missing teeth. On the other hand, age-wise comparisons revealed a significant difference (P< 0.05) in the case of maxillary overjet and openbite. The age, race, the level of expectations (probably affected by their culture), and socioeconomic status of each population might contribute to such findings.[22],[31]

It has been emphasized in several studies [31],[32] that a disadvantage of the DAI is the lack of recording about certain features, which may be a strong indication of treatment need like midline discrepancy, increased overbite, or buccal crossbite; it has to be kept in mind that the DAI identifies certain occlusal features, which constitute esthetic impairment. Therefore, this index could overestimate treatment need in some cases, but it has the advantage of being simple and less time consuming, with high reliability and requires less professional knowledge of occlusal traits as compared to other indexes.[33],[34],[35] For all these reasons, the DAI may be considered the most appropriate.

An epidemiological analysis of the major oral health problems in India has evidenced a lack of data related to malocclusion in a young adult population based in a rural setup. The assessment of the severity of the malocclusion in relation to orthodontic treatment need would be important to policy makers and orthodontists with implications on the provision of care and the use of limited resources. It may also help in assessing the appropriate resources required, such as materials, manpower, facilities and time.

Limitations

Although the study has successfully revealed the extent and severity of malocclusion, a limitation of the study could be the fact that only a single index (DAI) was used to assess the parameters. Other popular indices such as the IOTN-Dental Health Component could also be used and then the results compared to form a common consensus. A larger sample can also be included from various rural areas in different regions to facilitate comparison and generalization of the findings.

Recommendations

This epidemiological study has revealed the extent of dental problems, and this may help to plan out the appropriate preventive measures to the population in need. Since malocclusion develops over time, school-based oral health educational programs should be established where the development of any malocclusion can be checked at an early age and thus will not manifest when the person grows older. It is recommended that regular dental services along with oral health education as well as community preventive programs should be developed to reduce the risk of further oral disease occurrence. Health services will need to be tailored to suit the particular rural region. Reinforcement of dental health education could be implied to children from teachers and parents education. Also, nongovernmental organizations and dental teaching institutions/hospitals in the vicinity should be motivated to provide sufficient manpower, dental education and treatment services for the oral well-being of this rural population.


  Conclusion Top


Around 45.15% of the total sample had severe to very severe malocclusion indicating a highly desirable and mandatory orthodontic treatment need. Gender-wise differences were not found to be significant however the differences between the age groups showed statistical significance. In this population, malocclusion was characterized by a relatively low frequency of missing teeth, mandibular overjet and open bite.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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



 

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