Introduction: Hearing loss is an important public health issue that negatively affects children’s speech, cognitive development, academic performance, and social interaction. Even mild hearing impairment may lead to adverse developmental outcomes. However, data on hearing loss among primary school children in Mongolia remain limited. Goals: To determine the prevalence, type, and severity of hearing loss among primary school students in Ulaanbaatar and to assess associated socio-demographic factors. Material and Method: A school-based cross-sectional study was conducted among 1,254 primary school students. Hearing screening was performed using pure-tone audiometry following a standardized protocol. Students who failed the screening were referred for confirmatory diagnostic audiometry. Hearing loss was classified as mild (21–35 dB), moderate (36–50 dB), and severe (≥50 dB). Socio-demographic data were collected using a structured questionnaire. Statistical analysis data were analyzed using RStudio software. Descriptive statistics were used to summarize participant characteristics. Associations between hearing loss and independent variables were examined using chi-square tests and logistic regression analysis. Variables with p<0.20 in univariate analysis were included in the multivariable logistic regression model. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported, and p<0.05 was considered statistically significant. Ethical considerations: The study protocol was approved by the Institutional Ethics Committee (Approval No. 2024/3 06). Written informed consent was obtained from parents or legal guardians, and assent was obtained from participating students prior to data collection. Results: Of the 1,254 students, 116 (9.2%) required further evaluation, and hearing loss was confirmed in 23 students (1.8%). Most cases were mild in severity. Paternal education level was significantly associated with hearing loss (p=0.028), whereas no significant associations were observed for sex or household income. Conclusion The prevalence of hearing loss among primary school students in Ulaanbaatar was 1.8%, with most cases being mild and unilateral. These findings highlight the importance of implementing regular school-based hearing screening programs and improving parental awareness of children’s hearing health.

Background: Hearing loss among adolescents remains an important public health concern, as even mild degrees of hearing impairment can adversely affect cognitive development, academic performance, and social interaction. In Mongolia, evidence on the prevalence of hearing loss among school-aged children is limited, providing the rationale for conducting this study. Aim: To determine the prevalence, type, and severity of hearing loss and to assess associated demographic factors among middle and high school students in Ulaanbaatar, Mongolia. Materials and Methods: A school-based cross-sectional study was conducted during 2024–2025 among 1,803 students from 18 general education schools across nine districts of Ulaanbaatar. Hearing screening was performed using pure-tone audiometry according to a standardized protocol, and students who failed the initial screening underwent confirmatory audiometric testing. Hearing loss was classified as mild (21–35 dB), moderate (36–50 dB), or severe (≥50 dB). Demographic information was collected from parents or guardians using a structured questionnaire. Data were analyzed using R software. Associations were assessed using the chi-square (χ²) test, with p<0.05 considered statistically significant. Result: Among the students screened, 7.4% were identified as requiring further evaluation, and hearing loss was confirmed in 2.3%. Parental educational level was significantly associated with hearing loss, while no significant differences were observed by sex. Conclusion The prevalence of hearing loss among middle and high school students in general education schools in Ulaanbaatar was 2.3%, with no significant difference by sex. Most identified cases were mild and unilateral, highlighting the need for regular school-based hearing screening and strengthened parental health education. The association between parental educational level and hearing loss suggests the importance of addressing social determinants, and further studies are warranted to explore additional risk factors such as the use of personal listening devices.

Background: Anterior open bite involving the anterior dentition associated with skeletal Class III malocclusion is a severe dentofacial deformity resulting from discrepancies in vertical and sagittal relationships of the maxilla and mandible. In adult patients, orthodontic treatment alone is insufficient to achieve satisfactory outcomes; therefore, combined orthodontic and orthognathic surgical treatment is required. Case Presentation: A 21-year-9-month-old female patient presented with a chief complaint of mandibular prognathism. Clinical and radiographic examinations revealed anterior open bite involving the anterior dentition associated with skeletal Class III malocclusion. The treatment was carried out in three phases. Presurgical orthodontic treatment was performed to achieve dental decompensation, followed by orthognathic surgery. Le Fort I osteotomy was performed to reduce the vertical height by 3 mm and advance the maxilla by 5 mm, while bilateral sagittal split osteotomy (BSSO) was performed to set back the mandible by 9 mm. Post-surgical orthodontic treatment was performed using temporary anchorage devices (TADs) to provide stable anchorage, allowing precise control of tooth movement, and intermaxillary elastics were used to refine occlusion. As a result, facial profile, skeletal relationships, and occlusion were improved, with stable outcomes achieved. Diagnosis: Extraoral examination revealed a mandibular facial profile, increased height of the lower third of the face, normal facial midline at the nose, and a 1.5 mm leftward deviation at the chin. Lip position was -6 mm for the upper lip and -2 mm for the lower lip relative to the nasolabial angle. The angle between the cheekbones and the lips was 55.5°. Conclusion Combined orthodontic and orthognathic surgical treatment provides effective and stable outcomes in terms of esthetics, function, and occlusal stability in adult patients with anterior open bite associated with skeletal Class III malocclusion.