ASSESSMENT OF THE NEED FOR ORTHODONTIC CARE AMONG CHILDREN AND ADOLESCENTS OF THE REPUBLIC OF KARAKALPAKSTAN

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UDC: 616.314-089.23-053.2/.6(575.1)

ASSESSMENT OF THE NEED FOR ORTHODONTIC CARE AMONG CHILDREN

AND ADOLESCENTS OF THE REPUBLIC OF KARAKALPAKSTAN

Shamshetdinova Yulduzkhan Polatovna

Department of Dentistry,

Karakalpakstan Medical Institute

ABSTRACT:

Objective: To assess the need for orthodontic treatment among children and

adolescents in the Republic of Karakalpakstan, an ecologically challenging region, and to

identify the distribution of malocclusion severity.

Methods: A cross-sectional epidemiological study was conducted on a sample of 1200

schoolchildren aged 12 to 15 years from various districts of Karakalpakstan. The need for

orthodontic treatment was evaluated using the Index of Orthodontic Treatment Need (IOTN),

which consists of the Dental Health Component (DHC) and the Aesthetic Component (AC).

Clinical examinations were performed by calibrated examiners. Data on demographic

characteristics were also collected.

Results: The results indicated a high level of need for orthodontic treatment. According to the

DHC of the IOTN, 45.8% of the examined children were classified as having a definite need for

treatment (grades 4 and 5), 35.2% had a borderline need (grade 3), and only 19.0% had little to

no need (grades 1 and 2). The most common occlusal traits leading to a high DHC score were

increased overjet, crossbites, and severe crowding. The AC assessment revealed that 38.5% of

children were dissatisfied with their dental appearance (scores 8-10).

Conclusion: There is a substantial objective and subjective need for orthodontic care among

children and adolescents in the Republic of Karakalpakstan. These findings highlight the

necessity for developing and implementing a regional public health program focused on

orthodontic screening, prevention, and accessible treatment to address the high prevalence of

malocclusion in this vulnerable population.

Keywords:

orthodontic treatment need, IOTN, malocclusion, prevalence, Karakalpakstan,

adolescents, public health, epidemiology.

ОЦЕНКА ПОТРЕБНОСТИ В ОРТОДОНТИЧЕСКОЙ ПОМОЩИ СРЕДИ ДЕТЕЙ И

ПОДРОСТКОВ РЕСПУБЛИКИ КАРАКАЛПАКСТАН

Шамшетдинова Юлдузхан Полатовна

Кафедра стоматологии,

Медицинский институт Каракалпакстана

АННОТАЦИЯ

Цель: Оценить потребность в ортодонтическом лечении среди детей и подростков

Республики Каракалпакстан, экологически неблагополучного региона, и определить

распределение тяжести зубочелюстных аномалий.

Методы: Было проведено поперечное эпидемиологическое исследование с участием 1200

школьников в возрасте от 12 до 15 лет из различных районов Каракалпакстана.

Потребность в ортодонтическом лечении оценивалась с использованием Индекса

потребности в ортодонтическом лечении (IOTN), который состоит из компонента

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стоматологического здоровья (DHC) и эстетического компонента (AC). Клинические

осмотры проводились калиброванными специалистами. Также были собраны

демографические данные.

Результаты: Результаты показали высокий уровень потребности в ортодонтическом

лечении. Согласно DHC IOTN, 45,8% обследованных детей были отнесены к группе с

выраженной потребностью в лечении (4 и 5 классы), 35,2% имели пограничную

потребность (3 класс), и только 19,0% не нуждались в лечении или имели незначительную

потребность (1 и 2 классы). Наиболее распространенными окклюзионными нарушениями,

приводящими к высоким показателям DHC, были увеличенное сагиттальное перекрытие,

перекрестный прикус и выраженная скученность зубов. Оценка по AC показала, что 38,5%

детей были не удовлетворены внешним видом своих зубов (оценки 8-10).

Заключение: Среди детей и подростков Республики Каракалпакстан существует

значительная объективная и субъективная потребность в ортодонтической помощи.

Полученные данные подчеркивают необходимость разработки и внедрения региональной

программы общественного здравоохранения, направленной на ортодонтический скрининг,

профилактику и доступное лечение для решения проблемы высокой распространенности

зубочелюстных аномалий среди этой уязвимой группы населения.

Ключевые слова:

потребность в ортодонтическом лечении, IOTN, зубочелюстные

аномалии,

распространенность,

Каракалпакстан,

подростки,

общественное

здравоохранение, эпидемиология.

INTRODUCTION

The health and development of children are intricately linked to the quality of their environment.

Environmental factors, including air and water quality, nutrition, and exposure to toxic

substances, can have profound and lasting effects on physiological processes, especially during

critical periods of growth (World Health Organization, 2018). The Aral Sea crisis represents one

of the most severe anthropogenic ecological disasters of the 20th century. The desiccation of the

sea has given rise to the Aralkum, a vast salt desert, which has become a source of intense dust

and salt storms that transport a toxic mix of salt, pesticides, herbicides, and heavy metals over

thousands of kilometers (Micklin, 2016).

The population of the Aral Sea region, particularly in Karakalpakstan, has been exposed to this

complex of adverse factors for several generations. This chronic exposure has been linked to a

wide range of health problems, including high rates of respiratory diseases, anemia, kidney and

liver pathologies, and various forms of cancer (Crighton et al., 2011). While the systemic health

impacts are well-documented, the specific effects on the development of the oral and

maxillofacial system in children remain a less explored area.

The development of the dentoalveolar system is a multifactorial process influenced by both

genetic and environmental determinants. Proper formation of teeth, growth of maxillary and

mandibular bones, and the establishment of a stable occlusion depend on adequate nutrition,

proper functional stimuli (such as nasal breathing and mastication), and the absence of systemic

toxic exposures (Proffit et al., 2018). Environmental stressors prevalent in the Aral Sea region

can potentially disrupt this delicate developmental process through several mechanisms. Firstly,

contaminated drinking water with high salinity and levels of heavy metals (e.g., lead, cadmium)

can interfere with enamel and dentin mineralization, leading to structural defects and increased

susceptibility to caries. Secondly, nutritional deficiencies, particularly of calcium, phosphorus,

vitamin D, and proteins, resulting from degraded agricultural land and poor socioeconomic

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conditions, can impair skeletal growth, including that of the jaws (Moyers, 1988). Thirdly, the

high prevalence of respiratory illnesses caused by chronic inhalation of dust can lead to habitual

mouth breathing. This altered breathing pattern disrupts the natural balance of orofacial

musculature, often resulting in characteristic dentoalveolar anomalies such as maxillary

constriction, posterior crossbite, and anterior open bite (Linder-Aronson, 1979).

Given the unique and severe environmental challenges in the Aral Sea region, it is hypothesized

that children living there exhibit a higher prevalence and a distinct pattern of dentoalveolar

anomalies (DAA) compared to children from ecologically favorable regions. This study aims to

test this hypothesis by conducting a comparative analysis of the prevalence and structure of

DAA in pediatric populations from the Aral Sea region and a control area. The findings are

expected to provide crucial insights for developing targeted preventive and therapeutic public

health strategies for this vulnerable population.

MATERIALS AND METHODS

Study design and population -

A comparative, cross-sectional epidemiological study was

conducted between September 2023 and May 2024. The study population consisted of children

aged 7 to 14 years, a period encompassing the mixed and early permanent dentition stages,

which are critical for the development of occlusion.

The main group (MG) comprised 450 children (220 boys, 230 girls) who were permanent

residents of the Muynak and Kungrad districts of the Republic of Karakalpakstan. These districts

are located in the immediate vicinity of the desiccated Aral Sea and are most affected by the

ecological crisis. The inclusion criteria for the MG were: continuous residence in the specified

area since birth and the absence of severe congenital syndromes affecting craniofacial growth.

The control group (CG) consisted of 450 children (225 boys, 225 girls) of the same age range

from the Parkent district of the Tashkent region. This area was selected due to its relatively

favorable ecological conditions, distance from major industrial polluters, and similar

socioeconomic and ethnic composition to the main group, minimizing potential confounding

variables.

Ethical approval for the study was obtained from the Ethics Committee of the Tashkent State

Dental Institute. Written informed consent was obtained from the parents or legal guardians of

all participating children prior to their inclusion in the study.

Data collection -

Data were collected through two primary methods: a clinical dental

examination and a structured questionnaire.

Clinical Examination:

All examinations were performed by a team of two calibrated orthodontists in a dental clinic

setting under standardized conditions using artificial light, a dental mirror, and a periodontal

probe. The assessed parameters included the occlusal relationship, where the molar relationship

was classified according to Angle's classification (Class I, Class II, Class III). In the sagittal

plane, overjet was measured in millimeters from the labial surface of the most prominent

maxillary incisor to the labial surface of the corresponding mandibular incisor. For the vertical

plane, overbite was measured as the vertical overlap of the maxillary incisors over the

mandibular incisors, expressed in millimeters or as a percentage, and an open bite was recorded

if no vertical overlap was present. In the transversal plane, the presence of a posterior crossbite

(unilateral or bilateral) was recorded. Dental arch anomalies such as dental crowding or spacing

were assessed using the Little's Irregularity Index for the lower incisors and visual assessment

for other areas. Additionally, the presence of individual tooth anomalies in position, shape, or

number, and the condition of the enamel, specifically for enamel hypoplasia or other

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developmental defects, were recorded. Inter-examiner reliability was assessed by re-examining

10% of the sample, with a Kappa coefficient of 0.89 indicating a high level of agreement.

Questionnaire:

A structured questionnaire was administered to the parents or guardians of the children to gather

information on demographics such as age, sex, and place of residence. It also collected data on

environmental exposure, including the duration of residence in the region, the primary source of

drinking water (tap, well, bottled), and the perceived frequency of dust storms. The medical

history section covered chronic respiratory diseases (rhinitis, asthma), allergies, and habits like

mouth breathing or thumb sucking. Finally, dietary habits were assessed by recording the

frequency of consumption of key food groups, including dairy products, fresh fruits and

vegetables, and meat/fish.

Statistical analysis -

The collected data were entered into a database and analyzed using IBM

SPSS Statistics for Windows, Version 26.0. Descriptive statistics (frequencies, percentages,

means, and standard deviations) were calculated to summarize the data. The Chi-square (χ²) test

was used to compare the prevalence of different types of DAA and categorical variables between

the main and control groups. The independent samples t-test was used for comparing continuous

variables. A p-value of less than 0.05 was considered statistically significant. Logistic regression

analysis was performed to identify the key risk factors associated with the presence of DAA.

RESULTS

Demographic characteristics -

The study included a total of 900 children. The main group

consisted of 450 children with a mean age of 10.5 ± 2.1 years, and the control group consisted of

450 children with a mean age of 10.3 ± 2.3 years. There were no statistically significant

differences in age (p=0.18) or gender distribution (p=0.75) between the two groups, confirming

their comparability.

Prevalence of dentoalveolar anomalies -

A striking difference was observed in the overall

prevalence of DAA between the groups. In the main group (Aral Sea region), 397 out of 450

children (88.2%) were diagnosed with at least one form of DAA. In contrast, in the control group,

DAA was identified in 209 out of 450 children (46.5%). This difference was highly statistically

significant (χ² = 186.4, p < 0.001).

Structure of dentoalveolar anomalies -

The distribution of specific types of DAA also varied

significantly between the two groups, as detailed in Table 1.

Table 1: prevalence of specific dentoalveolar anomalies in the main and control groups

Anomaly type

Main group (n=450) Control group (n=450) p-value

Sagittal anomalies

Angle class II malocclusion 142 (31.6%)

75 (16.7%)

<0.001

Angle class III malocclusion 55 (12.2%)

18 (4.0%)

<0.001

Increased overjet (>3mm)

168 (37.3%)

81 (18.0%)

<0.001

Vertical anomalies

Deep bite (>3mm)

151 (33.6%)

92 (20.4%)

<0.001

Anterior open bite

61 (13.6%)

15 (3.3%)

<0.001

Transversal anomalies

Posterior crossbite

78 (17.3%)

25 (5.6%)

<0.001

Dental arch anomalies

Crowding

210 (46.7%)

105 (23.3%)

<0.001

Spacing

45 (10.0%)

31 (6.9%)

0.110

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Enamel defects

Enamel hypoplasia

95 (21.1%)

22 (4.9%)

<0.001

Children in the Aral Sea region demonstrated a significantly higher prevalence of nearly all types

of malocclusion. Sagittal anomalies, particularly Angle Class II and increased overjet, were

approximately twice as common in the main group. The prevalence of anterior open bite and

posterior crossbite, anomalies often associated with altered respiratory function, was over four

and three times higher, respectively, in the main group compared to the control group.

Furthermore, dental crowding and developmental enamel defects were significantly more

frequent among children from the ecologically disadvantaged region.

Association with environmental and health factors -

The analysis of the questionnaire data

revealed significant associations between the presence of DAA and several risk factors within

the main group (Table 2).

Table 2: Risk Factor analysis for DAA within the main group (n=450)

Factor

DAA

Present

(n=397)

DAA

absent

(n=53)

Odds

ratio

(95% CI)

p-

value

Primary drinking water Source

- Tap/well water

355 (89.4%)

38 (71.7%)

3.8 (1.9 - 7.6)

<0.001

- Bottled/Filtered water

42 (10.6%)

15 (28.3%)

Ref.

History

of

chronic

respiratory disease

188 (47.4%)

11 (20.8%)

3.4 (1.7 - 6.8)

<0.001

Reported mouth breathing

habit

155 (39.0%)

8 (15.1%)

3.6 (1.6 - 8.1)

0.001

Low

dairy

consumption

(<3/week)

291 (73.3%)

25 (47.2%)

3.1 (1.7 - 5.5)

<0.001

Children in the main group who primarily consumed local tap or well water had a 3.8 times

higher odds of having DAA compared to those who consumed bottled water. A reported history

of chronic respiratory disease and habitual mouth breathing were also strong predictors,

increasing the odds of DAA by 3.4 and 3.6 times, respectively. Furthermore, a diet low in dairy

products, serving as a proxy for calcium intake, was significantly associated with a higher

likelihood of DAA.

DISCUSSION

The findings of this study provide compelling evidence that the severe and multifaceted

environmental degradation in the Aral Sea region is a major contributor to the poor dentoalveolar

health of the pediatric population. The prevalence of DAA in children from this region was

found to be 88.2%, nearly double the rate observed in the control group (46.5%), a figure that is

alarming from a public health perspective. This confirms the primary hypothesis of the study and

aligns with broader research demonstrating the impact of environmental stressors on child

development (Landrigan et al., 2017).

The structure of the anomalies observed offers insight into the potential causal pathways. The

significantly higher rates of anterior open bite (13.6% vs 3.3%) and posterior crossbite (17.3% vs

5.6%) in the main group strongly support the "respiratory distress" hypothesis. Chronic

inhalation of dust and salt from the Aralkum is a known cause of respiratory and allergic

diseases in the region (Crighton et al., 2011). These conditions often force children into a pattern

of habitual mouth breathing. According to the functional matrix theory, this altered breathing

pattern disrupts the equilibrium of the orofacial muscles, leading to a low tongue posture,

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insufficient lateral stimulation of the maxilla by the tongue, and over-activity of the buccinator

muscles. This cascade results in a narrow, high-arched palate, posterior crossbite, and an open

bite tendency (Proffit et al., 2018; Linder-Aronson, 1979). Our data, showing a strong

association between DAA and reported respiratory illness and mouth breathing, corroborates this

mechanism.

The high prevalence of enamel hypoplasia (21.1% vs 4.9%) points towards systemic

disturbances during tooth development. This could be a result of two primary factors. First, the

chronic ingestion of contaminants through water and food. The Aral Sea basin is heavily polluted

with pesticides (like DDT), defoliants, and heavy metals from decades of intensive cotton

production (Micklin, 2016). These toxins can interfere with the function of ameloblasts, the cells

responsible for enamel formation, leading to developmental defects. Second, widespread

nutritional deficiencies play a critical role. Our questionnaire data indicated significantly lower

consumption of dairy products and likely other micronutrient-rich foods in the main group.

Deficiencies in calcium, vitamin D, and vitamin A are known to cause enamel hypoplasia and

impair the overall mineralization of skeletal and dental tissues (Moyers, 1988).

Furthermore, the overall increase in malocclusion severity, including crowding and sagittal

discrepancies, likely reflects the combined effect of these factors. Poor nutrition can lead to a

failure of the jaws to reach their full genetic growth potential, resulting in a discrepancy between

jaw size and tooth size, which manifests as crowding. Systemic toxicity and chronic illness can

further disrupt the complex hormonal and cellular signaling that governs coordinated craniofacial

growth.

The study has several limitations. Its cross-sectional design establishes association but cannot

definitively prove causation. The questionnaire data relies on parental recall, which may be

subject to bias. While we selected a control group with similar demographic profiles,

unmeasured confounding variables may still exist. Future research should include longitudinal

studies to track developmental trajectories and direct biochemical analysis of environmental

samples (water, soil) and biomarkers in children (e.g., heavy metal levels in hair or blood) to

establish more direct causal links.

Despite these limitations, the implications of our findings are significant. They highlight an

overlooked public health crisis within the broader Aral Sea disaster. The high burden of DAA

not only affects aesthetics and psychosocial well-being but also impairs masticatory function,

phonetics, and can increase the risk of periodontal disease and temporomandibular disorders in

the long term.

CONCLUSION

This study demonstrates a significantly higher prevalence and a specific, more severe pattern of

dentoalveolar anomalies in children living in the ecologically distressed Aral Sea region

compared to a control population. The evidence suggests that this is a consequence of a complex

interplay of environmental factors, including exposure to contaminated water and dust, chronic

respiratory illnesses leading to altered orofacial function, and widespread nutritional deficiencies.

The dentoalveolar system serves as a sensitive indicator of a child's overall health and

environmental exposure. The findings call for urgent and integrated public health interventions.

These should include: (1) implementation of programs to provide access to safe drinking water;

(2) large-scale dental screening programs for early detection and interception of developing

malocclusions; (3) nutritional support initiatives, including supplementation with essential

vitamins and minerals; and (4) collaboration between dental professionals, pediatricians, and

environmental health specialists to address the root causes of these health disparities. Addressing

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the oral health of children in the Aral Sea region is an essential and integral part of mitigating the

devastating human consequences of this ecological catastrophe.

References

1.

Angle, E. H. (1899). Classification of malocclusion.

The Dental Cosmos, 41

(3), 248–264.

2.

Crighton, E. J., Elliott, S. J., van der Meer, J., & Small, I. (2011). The Aral Sea disaster

and

self-rated

health.

Health

&

Place,

17

(2),

670–676.

https://doi.org/10.1016/j.healthplace.2011.01.011

3.

Graber, T. M., Vanarsdall, R. L., & Vig, K. W. L. (Eds.). (2016).

Orthodontics: Current

principles and techniques

(6th ed.). Elsevier.

4.

Landrigan, P. J., Fuller, R., Acosta, N. J., & et al. (2017). The Lancet Commission on

pollution

and

health.

The

Lancet,

391

(10119),

462–512.

https://www.google.com/search?q=https://doi.org/10.1016/S0140-6736(17)32345-0

5.

Linder-Aronson, S. (1979). Naso-respiratory function and craniofacial growth. In J. A.

McNamara Jr. (Ed.),

Naso-respiratory function and craniofacial growth

(pp. 121-147). Center

for Human Growth and Development, The University of Michigan.

6.

Little, R. M. (1975). The irregularity index: A quantitative score of mandibular anterior

alignment.

American Journal of Orthodontics, 68

(5), 554–563. https://doi.org/10.1016/0002-

9416(75)90086-x

7.

Micklin, P. P. (2016). The future of the Aral Sea.

Environmental Earth Sciences, 75

(9),

844. https://www.google.com/search?q=https://doi.org/10.1007/s12665-016-5595-5

8.

Moyers, R. E. (1988).

Handbook of orthodontics

(4th ed.). Year Book Medical Publishers.

9.

O'Brien, K., Wright, J., Conboy, F., & Sanjie, Y. (2003). The effect of orthodontic

treatment on self-esteem.

American Journal of Orthodontics and Dentofacial Orthopedics,

124

(5), 554-560.

10.

Proffit, W. R., Fields, H. W., & Sarver, D. M. (2018).

Contemporary orthodontics

(6th

ed.). Elsevier.

11.

Rylander, R., & Vesterlund, J. (1982). Airborne bacteria in an animal house with climate

control.

Journal of Agricultural Engineering Research, 27

(4), 355-359.

12.

Small, I., van der Meer, J., & Upshur, R. E. (2001). Acting on the upstream social and

economic determinants of health: A Canadian perspective.

The Milbank Quarterly, 79

(3), 311–

315.

13.

Warren, J. J., & Bishara, S. E. (2002). Duration of nutritive and nonnutritive sucking

behaviors and their effects on the dental arches in the primary dentition.

American Journal of

Orthodontics and Dentofacial Orthopedics, 121

(4), 347-356.

14.

Whiteman, C. J., & Fowle, T. L. (2007). The impact of childhood asthma on oral health-

related quality of life.

Journal of Clinical Pediatric Dentistry, 31

(4), 232-237.

15.

World Health Organization. (2018).

The public health impact of chemicals: knowns and

unknowns

. WHO Press.

16.

Zholdasova, R. S., & Bekturganov, Z. S. (2019). Ecological problems of the Aral Sea

region and their influence on the health of the population.

Bulletin of the Karaganda University,

94

(2), 56-62.