Background: Aviation security work requires a high level of responsibility, sustained vigilance, and shift- and night-work schedules. However, studies evaluating the interrelationship between the psychosocial work environment, stress, and oral health indicators among aviation security personnel are limited, which was the rationale for this study. Aim: This study aimed to determine the relationship between oral health and some risk factors among aviation security personnel. Materials and Methods: An analytical cross-sectional study was conducted among 132 aviation security personnel. The psychosocial work environment was assessed using the Job Content Questionnaire (JCQ), perceived stress using the 10-item Perceived Stress Scale (PSS-10), and oral health-related quality of life using the 14-item Oral Health Impact Profile (OHIP-14). Self-rated oral health, oral health behaviors, and related risk factors were assessed using relevant items from the standard adult questionnaire provided in the World Health Organization’s Oral Health Surveys: Basic Methods (5th edition, 2013). Clinical oral examinations included the Decayed, Missing and Filled Teeth (DMFT) index, Simplified Oral Hygiene Index (OHI-S), Community Periodontal Index (CPI), and assessment of tooth wear. Statistical analysis was performed. Result: The mean age of the participants was 39.22±8.24 years. Psychological job demands were positively correlated with PSS-10 scores (r=0.248, p=0.004), PSS-10 scores with OHIP-14 scores (r=0.215, p=0.013), and OHI-S scores with CPI scores (r=0.568, p<0.001). Bruxism and tooth wear were identified in 67.4% and 91.7% of participants, respectively, and the number of teeth affected by wear was significantly greater among participants with bruxism (p<0.001). In multivariable analysis, higher PSS-10 scores (B=0.776; 95% CI: 0.337–1.214; p=0.001) and tobacco-use risk (B=4.679; 95% CI: 0.671–8.688; p=0.022) were associated with higher OHIP-14 scores. Conclusion Higher psychological job demands were associated with higher levels of perceived stress, while perceived stress was associated with poorer oral health-related quality of life. Oral hygiene status was associated with periodontal status, and bruxism was associated with tooth wear.

Background: Dental caries remains a major public health concern among children and adolescents in Mongolia. The mineral composition of drinking water-particularly fluoride and other essential minerals plays a crucial role in enamel mineralization and caries prevention. Fluoride directly influences the demineralization–remineralization balance of dental enamel and forms a temporary layer of fluid fluorapatite on the enamel surface when exposed to acids, thereby reducing the critical pH for dissolution and increasing acid resistance. In addition, fluoride inhibits the acid-producing metabolism of bacteria such as s.mutans within the biofilm and lowers biofilm acidity, thus slowing the rate of demineralization. Therefore, determining the relationship between population groups and water mineralization is essential for developing effective preventive strategies. Aim: To determine the severity and prevalence of dental caries among 5-, 12-, and 15-year-old children living in the 21 provinces of Mongolia and to evaluate the effects of selected minerals in drinking water (Ca, Mg, Cl, F) on dental caries. Materials and Methods: The study utilized oral examination data from a total of 421,970 children aged 0-17 years across 21 provinces and 321 soums in Mongolia. Sampling was conducted in Ulaanbaatar city (48.1%) and in all 21 rural provinces. Dental caries was assessed according to WHO criteria, and the effects of minerals in drinking water were analyzed using linear regression. Result: The average caries severity of primary teeth in 5-year-old children was 3.0-3.1 dft, which was higher than the caries severity of permanent teeth in 12- and 15-year-olds (1.54DMFdft–1.93 DMFT). Among 5-year-olds, boys had a slightly higher caries severity (3.17±3.52) compared to girls (2.92±3.40), while in the 12- and 15-yearold groups, girls showed higher caries severity than boys. Overall, 5566% of children had at least one carious tooth, and the prevalence among 5-year-olds was 63.5-66.2%. Linear regression analysis showed that fluoride (beta=–0.449, p<0.001) and magnesium (beta=–0.031, p<0.001) in drinking water had a statistically significant protective effect in reducing dental caries in both primary and permanent teeth. Conclusion The findings indicate that fluoride (F) and magnesium (Mg) in drinking water are important protective elements against dental caries, whereas calcium (Ca) and chloride (Cl) show no consistent association with caries experience.

Background: Conventional methods for assessing exposure to environmental tobacco smoke rely mainly on questionnaires and biomarkers with short half-lives, such as urinary cotinine. In contrast, oral mucosal pigmentation may represent a visible, non-invasive biomarker of chronic exposure. However, its clinical and policy relevance, as well as its validity for screening purposes, remain insufficiently established. Aim: To summarize the evidence on the association between exposure to environmental tobacco smoke and oral mucosal pigmentation and to assess some confounding factors. Materials and Methods: We synthesized findings from observational studies that examined the association between environmental tobacco smoke exposure and oral mucosal pigmentation across all age groups. International electronic databases, including PubMed, Embase, Web of Science, and Scopus, were searched. Data were extracted on exposure–response relationships, measurement instruments, anatomical distribution of pigmentation, confounding by physiological pigmentation, and biochemical validation. The quality of included studies was assessed using the Mixed Methods Appraisal Tool (MMAT). A narrative synthesis was conducted, focusing on the biological plausibility of the biomarker, standardization of measurement, and its potential implications for screening and tobacco control policy. Results: Thirteen observational studies from seven countries, involving a total of 3,284 participants, met the inclusion criteria. Four studies reported a statistically significant association between duration of exposure and severity of pigmentation, while one cohort study showed that urinary cotinine levels increased with age among children. The Gingival Pigmentation Index and the Dummett Oral Pigmentation Index were the most commonly used assessment tools; however, methodological heterogeneity limited direct comparability across studies. The anterior gingiva was the most frequently affected anatomical site. Only a limited number of studies adequately controlled for physiological pigmentation, and skin color was identified as an important confounding factor. The pooled odds ratio was 2.35; however, the certainty of evidence was low due to the observational nature of the included studies. Conclusion Oral mucosal pigmentation may serve as a potential biomarker of long-term exposure to environmental tobacco smoke. Nevertheless, standardized assessment protocols, adequate control for physiological pigmentation, and validation against “gold-standard” biomarkers are required. If validated, this marker could be used for rapid identification of high-risk groups and incorporated into tobacco control policies.

Background: Passive smoking among children remains a serious public health concern, particularly because children’s ability to avoid household environmental tobacco smoke exposure is limited when parents smoke. In recent years, increasing scholarly attention has been given to oral mucosal pigmentation as a potential clinical sign of long-term passive smoking in children. However, no previous study has synthesized the available evidence on this topic. Aim: This systematic review and meta-analysis aimed to evaluate the association between passive smoking and oral pigmentation in children. Materials and Methods: A systematic search was conducted in international electronic databases, including PubMed, Scopus, Web of Science, and the Cochrane Library, in accordance with PRISMA guidelines. Observational studies assessing the association between passive smoking and oral pigmentation among children aged ≤18 years were included. Methodological quality was assessed using the Mixed Methods Appraisal Tool (MMAT). A random-effects meta-analysis was performed, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Between-study heterogeneity was assessed using the I² statistic, and the certainty of evidence was evaluated using the GRADE approach. Results: Seven studies involving a total of 1,582 participants met the inclusion criteria. The meta-analysis demonstrated that passive smoking was significantly associated with an increased risk of oral pigmentation in children, with a pooled OR of 2.58 (95% CI, 1.35-4.95; p=0.004). Compared with children without exposure to passive smoking, those exposed to environmental tobacco smoke had an absolute risk increase of 17% (95% CI, 6.3%-23.9%). Subgroup analysis by assessment method showed a consistent effect among studies using the Gingival Pigmentation Index (GPI) (OR, 2.12; 95% CI, 1.58-2.84), whereas studies using the Dummett Oral Pigmentation Index (DOPI) showed a wider confidence interval (OR, 3.26; 95% CI, 0.68-15.54). According to the MMAT assessment, the included studies demonstrated adequate participant selection in 100% of cases, appropriate outcome measurement in 76.9%, and adequate control of confounding factors in 46.2%. Owing to the observational nature of the included studies, moderate heterogeneity, and the potential risk of confounding by physiological pigmentation, the certainty of evidence was rated as low according to GRADE. Conclusion Children exposed to environmental tobacco smoke had a significantly higher likelihood of oral mucosal pigmentation than unexposed children. These findings suggest that screening for oral mucosal pigmentation during pediatric oral examinations may serve as a non-invasive marker of passive smoking exposure and may provide visible clinical evidence to support counseling parents on smoking cessation and smoke-free household environments.

Background: Mongolia ranks first in the world for liver cancer incidence and mortality, with more than 95% of cases associated with hepatitis B virus infection. Healthcare professionals are considered a priority group for vaccination. Aim: To investigate the level of hepatitis B virus immunization among dental specialist physicians. Materials and Methods: This retrospective, observational, analytical cross-sectional study was conducted with approval from the Research Ethics Committee of the Mongolian National University of Medical Sciences (MNUMS). We analyzed serum test data from 76 dentists officially registered in the Dentistry residency program during the 2025–2026 academic year, assessing hepatitis B virus infection status and immunization levels. Statistical analysis of quantitative data was performed using SPSS version 27. Results: Data from 76 dentists were analyzed. The mean age was 28.5±6.2 years; by age group, 70% (n=53) were aged 20–29 years, 22.3% (n=17) were 30–39 years, and 7.8% (n=6) were over 40 years (p<0.05). By sex, 13.2% (n=10) were male (p>0.05). Among the study participants, 97.4% were HBV-negative with a mean age of 28.2±5.3 years (Median: 27.0, IQR: 24.0–31.0), whereas 2.6% were infected; the mean age of infected physicians was 43.5±2.1 years (Median: 43.5, IQR: 42.0–45.0), indicating a high and statistically significant occurrence of HBV infection in the age group over 40 years (Fisher’s exact test, p=0.05). When classified by immunity level, 29.2% (n=19) had anti-HBs levels below 10 mIU/mL (insufficient), 24.6% (n=16) had anti-HBs levels of 10–99 mIU/mL (weak), and 46.2% (n=30) had anti-HBs levels above 100 mIU/mL (adequate immunity); however, no statistically significant association was observed between age groups and protective antibody levels (Fisher’s exact test, p=0.892). Conclusion Among participants, the prevalence of hepatitis B virus infection was 2.6%, vaccination coverage was 85.5%, and anti-HBs antibody titers were adequate in 46.2%.

Background: Although a considerable number of oral health studies have been conducted among children in Mongolia, most have focused on dental caries in school-aged children, and data on non-carious oral conditions in preschool children remain scarce. Aim: To determine the prevalence of oral mucosal, gingival and traumatic dental conditions among preschool children in Ulaanbaatar. Materials and Methods: In this cross-sectional pilot study, 686 children from six randomly selected kindergartens in Ulaanbaatar underwent oral examination in accordance with the World Health Organization (WHO) 2013 guidelines, using the WHO Oral Health Assessment Form for Children. The main outcomes were oral mucosal changes, including pigmentation, gingival bleeding, dental trauma and dental erosion. Analyses were restricted to the 598 children with complete records for these outcomes, and frequencies, percentages and Wilson 95% confidence intervals (CIs) were calculated using this common denominator (n=598). Results: Of the 598 children analysed, 86 (14.38%; 95% CI 11.80–17.42%) had at least one of the four main conditions. Dental erosion was observed in 74 children (12.37%; 95% CI 9.97–15.26%), confined to the enamel in 45 (7.53%) and extending into the dentine in 29 (4.85%). Oral mucosal changes were recorded in 10 children (1.67%; 95% CI 0.91–3.05%), gingival bleeding in 7 (1.17%; 95% CI 0.57–2.40%) and dental trauma in 1 (0.17%; 95% CI 0.03–0.94%), whereas oral mucosal pigmentation was observed in 64 children (10.70%; 95% CI 8.47–13.44%). Of the 86 children with findings, 85 (98.84%) attended two of the six participating kindergartens. Conclusion When dental caries was excluded, dental erosion was the most prevalent condition among preschool children, whereas oral mucosal changes, gingival bleeding and dental trauma were observed in a small proportion of children. The concentration of these findings in two of the six kindergartens may reflect local demographic and socioeconomic factors, as well as differences in examination and recording practices. Future studies should therefore standardise examination criteria in advance and include a larger number of kindergartens.

Background: The morphological characteristics of the alveolar bone thickness between the maxillary sinus and root ca nal tips of the premolars and molars is important for dental implant and orthodontic treatment. The hypotheses formulated were that there would be differences in the morphological characteristics of the alveolar bone at various tooth positions in the posterior maxilla and that age and sex would not influence the findings. This study may provide useful information for dental implant and mini-implant treatment, so as to help lead to successful treatment outcomes. Aim: To evaluate the vertical relationship between the maxillary sinus and molar teeth using cone beam computed tomography (CBCT). Materials and Methods: The study design was retrospective study. We selected 30 CBCT images that were taken in the Central Dental Hospital, Mongolian National University Medical Sciences (MNUMS), between 2021 and 2023. We collected all images according to the inclusion and exclusion criteria. We used Full CBCT (16cm*8cm) images using the target sampling method. The all CBCT images (85kW, 7mA) were obtained with HDX, WILL (DENTRI, Seoul, Korea) using OnDemand3D (CyberMed. Seoul. Korea). The vertical relationship between the maxillary sinus and the maxillary molars was classified into 5 categories according to Kwak’s classification. The study was approved by the Research Ethics Committee of MNUMS. Statistical analyses were done by IBM SPSS version 27 software. Results: A total of 202 maxillary premolars and molars were examined using CBCT images, and were taken in 30 patients. The patient group consisted of 12 men and 18 women with an average age of 26.87 years (range, 16–42 years). In the maxillary first premolars: Class I was 77.4%, Class II was 13.2%, Class V was 9.4%, Classes III and IV were not observed. In the maxillary second premolars: Class I was 44.8%, Class V was 37.9%, Class II was 17.2%. In the maxillary first molars: Class V was 62.3%, Class I was 24.4%, Class II was 6.7%, Class III was 4.4%, Class IV was 2.2%. In the maxillary second molars: Class V was 63.1%, Class I was 23.9%, Class II was 6.5%, Class III was 6.5%. When examining the distance from the apex of the root of the molars to the floor of the maxillary sinus, the distance between the root of the buccal side of the second molar was the smallest, 0.67±1.36mm, and the distance between the root of the first premolar was the furthest, 5.14±4.32mm (p<0.01). Conclusion Among the maxillary posterior teeth, the second molar was positioned closest to the floor of the maxillary sinus, whereas the first premolar was located at the greatest distance. Regarding the maxillary molars, Type V characterized by root protrusion into the floor of the maxillary sinus was the most frequently observed configuration. Conversely, for the premolars, Type I defined by a distinct separation from the sinus floor was the predominant anatomical relationship.

Background: Papillon-Lefevre Syndrome (PLS) is a rare genetic disorder, characterized by palmoplantar keratosis, aggressive periodontitis and premature edentulous primary and permanent dentition at a very young age. Additional symptoms and findings associated with PLS may include frequent pyogenic skin infections, abnormalities of the nails, and excessive perspiration. Case report The patient, who visited in the Central dental hospital was 3.6 years old. Pediatric dentist confirmed the diagnosis “PLS and chronic traumatic tongue ulcer” based on anamnesis and objective examination. Dental and tongue ulcer treatment was done once a week for 2 months. The recall system was carried out by 3 month intervals oral examination and 6 month intervals radiographic examinations under team of pediatric dentist, pediatrician and immunologist.

Background: In the revised ICD-11 and DSM-5-TR, Prolonged Grief Disorder (PGD) has been officially recognized as a distinct mental disorder. This condition is characterized by a grief reaction following the death of a close person that persists beyond the expected period (more than 12 months for adults in DSM-5-TR; more than 6 months in ICD-11), significantly impairing quality of life, social functioning, and psychological stability. To assist in the early detection and diagnosis of PGD, researchers at Weill Cornell Medicine, New York developed the Prolonged Grief Disorder–13, revised (PG-13-R) self-report measure in 2020, based on the diagnostic criteria of ICD-11 and DSM-5-TR. Although this instrument has been translated and validated in several languages, no validated Mongolian version has been available, forming the rationale for this study. Aim: To examine the psychometric properties—including reliability and validity—of the Mongolian version of the Prolonged Grief Disorder-13, revised (PG-13-R) scale. Materials and Methods: Permission to use the PG-13-R was obtained from the original author (H.G. Prigerson) in November 2024. The study proposal and methods were reviewed and approved by the Academic Council of the University of Humanities (Approval No. A/19), adhering to ethical research guidelines. The translation process followed international recommendations, including forward translation, back-translation, and expert review by linguists. A pilot test was conducted to ensure clarity of each item. The main study included 442 participants (81.9% female; mean age = 41.8±12.4 years) who had experienced bereavement at least six months prior to participation. Results: The Mongolian version of the PG-13-R demonstrated excellent internal consistency (Cronbach’s α = 0.92; McDonald’s ω = 0.93). The split-half correlation was r = 0.87, indicating high internal correlation. The test–retest reliability was strong, with an Intraclass Correlation Coefficient (ICC) of 0.82 (item ICCs ranging from 0.55 to 0.88), confirming temporal stability. The Content Validity Index (CVI) was 0.89, indicating good content validity. Regarding criterion and convergent validity, the Mongolian PG-13-R showed statistically significant negative correlations with the WHOQOL- BREF subdomains (physical health, psychological, social relationships, and environment) and moderate positive correlations with HADS anxiety and depression scores, consistent with theoretical expectations. Factor analysis results indicated that the data were suitable for analysis (KMO=0.93; Bartlett’s test p<0.001). A single factor with eigenvalue >1 emerged, explaining 62.1% of the total variance, with factor loadings ranging from 0.63 to 0.87, consistent with the original structure. Conclusion The Mongolian version of the PG-13-R scale exhibited a stable one-factor structure and demonstrated strong reliability and validity. It is a psychometrically sound and effective tool for assessing prolonged grief among the Mongolian population.

Background: The capital city of Mongolia, Ulaanbaatar is not only one of the coldest capitals in the world but has also become one of the most polluted cities in recent years due to the prolonged effects of severe cold. According to the World Health Organization (WHO), the most harmful air pollutant to human health is PM2.5. These fine particulate matters can penetrate the human body through the respiratory tract, causing various changes in the body and the oral cavity. Aim: Relationship between dental caries, gingivitis and periodontal status and PM2.5 air pollutant levels among 12 years old children in different areas of Ulaanbaatar. Materials and Methods: The study population consisted of 190 children aged 12 years old, who were selected from high and low level areas with air pollutant PM2.5 in Ulaanbaatar city, Mongolia. We obtained informed consent No.24-25/10-1 of the Ethical Committee, MNUMS. The oral examination of every child was done according to WHO recommendation (2013). We determined the prevalence of dental caries and mean DMFT score, and the prevalence of gingivitis, and CAL score. Statistical analysis was done by the SPSS 29 software. Results: The prevalence and mean DMF/t score of dental caries were 96% аnd 5.37±2.75 among children living in the high level area of the PM2.5 air pollutant; and 91% and 5.39±3.95 in the low level area, respectively (p<0.01). The prevalence of gingivitis was 23.2% among all children; 25.2% among children living in the high level area of the PM2.5 air pollutant and 20.5% in the low level area. The CAL score was 1.89±0.89 mm in the high polluted area and 1.94±0.77 mm in the low polluted area (p<0.001). Conclusion The prevalence of dental caries and gingivitis and the mean DMFT and CAL score among children living in air polluted areas were higher than low polluted areas.