Background: Speciality choice among graduating students is important for professional development and health workforce planning. Studies of medical graduates in the United Kingdom have reported that speciality preferences may change over time. Evidence concerning speciality choice among final-year dental students in Mongolia remains limited. Identifying students’ preferences and perceived influencing factors may inform curriculum development and career guidance. Aim: To identify the factors perceived to influence speciality choice among final-year dental students graduating from the School of Dentistry, MNUMS, in 2026. Materials and Methods: This cross-sectional questionnaire study included 111 of 136 eligible final-year students (81.6%). A questionnaire adapted from Svirko et al. (2013) collected demographic information, decision status, up to two preferred specialties, and ratings of nine potential influencing factors on a three-point Likert scale (strongly influenced=2, slightly influenced=1, not influenced=0). Descriptive statistics, Pearson’s chi-square test, and Spearman’s rank correlation coefficient were used, with statistical significance set at p<0.05. Result: Of the 111 respondents, 96 (86.5%) were female and 74 (66.7%) were aged 24–26 years. Sixty (54.1%) had not finalized their specialty choice, while 37 (33.3%) had made a definitive decision. Oral and Maxillofacial Surgery and Orthodontics were each mentioned by 48 respondents (43.2%), followed by Prosthodontics (25, 22.5%). Personal motivation and conviction had the highest mean rating (1.58/2.0), whereas family members’ decisions or traditions had the lowest (0.48/2.0). Teaching methodology and faculty attitudes/communication showed a strong positive correlation (Spearman’s ρ=0.72). The reported statistical results for sex-related comparisons require verification against the original dataset. Conclusion More than half of respondents had not finalized their specialty choice. Personal motivation received the highest perceived-influence rating, while family-related factors received the lowest. Teaching methodology and faculty attitudes/communication were strongly correlated. These findings may inform further evaluation of career guidance, training environments, and clinical learning opportunities. The single-institution, cross-sectional design limits generalizability and does not establish causality.

Background: Cerebral palsy (CP) is the most prevalent prenatal neurodevelopmental disorder, characterized by a group of permanent movement and postural syndromes resulting from early-stage brain injury. While prevalence varies globally (1.5 to 3.4 per 1,000 live births), the incidence in Mongolia is recorded at 1.89 per 1,000 live births. Although approximately one-third of children with CP are non-ambulatory, those classified within GMFCS Levels I, II, and III retain the ability to walk independently or with assistive devices. Quantitative gait analysis is essential for understanding motor impairments, optimizing treatment planning, and improving clinical prognosis. Aim: To determine the biomechanical characteristics of “Jump gait” in children with cerebral palsy. Materials and Methods: The study included 14 children aged 8–15 diagnosed with CP (GMFCS Level I) and a control group of 14 age-matched healthy children. Anthropometric data (age, sex, weight, height) were collected. Lower limb kinematics and kinetics were measured using a 3D optical motion capture system and force plates. Reflective markers were placed on specific anatomical landmarks to record gait cycles. Results: Comparative kinematic analysis revealed no significant difference in hip joint range of motion (ROM) between the CP and control groups. However, children with CP exhibited a significant reduction in knee ROM, specifically an inability to achieve full knee extension during the gait cycle. Regarding ankle kinematics, children with CP showed negative values (plantarflexion) during the initial heel strike phase, indicating a “Toe-walking” pattern. Statistical significance was observed in ankle ROM across all phases of the gait cycle. No statistically significant difference was found in the vertical ground reaction force (GRF) during the initial contact phase between the two groups. Conclusion The “Jump gait” pattern in children with CP is primarily characterized by restricted knee extension and excessive ankle plantarflexion rather than hip joint dysfunction. Quantifying these biomechanical deviations provides critical data for optimizing personalized rehabilitation and clinical interventions.

Background: Allergic and atrophic forms of chronic rhinitis are common among the population, characterized by a chronic progressive course with a tendency toward increasing prevalence. Worldwide, allergic rhinitis affects approximately 10–40% of adults and 2–25% of children. According to a study conducted in Mongolia, the prevalence of allergic rhinitis among adults in Ulaanbaatar was reported to be 23.6%, with an increasing trend anticipated in the future. In allergic and atrophic rhinitis, structural alterations occur in the nasal mucosa, including disruption of the normal architecture of the pseudostratified epithelium and ciliated cells, accompanied by changes in goblet cell number and dysfunction of their activity, resulting in a complex pathological process. In otorhinolaryngology practice in Mongolia, there is a relative lack of studies investigating the ultrastructural changes of the nasal mucosa in allergic and atrophic rhinitis. Aim: To compare ultrastructural and histological changes of the nasal mucosa in allergic and atrophic rhinitis. Materials and Methods: Ethical approval was obtained from the Research Ethics Review Committee of the Mongolian National University of Medical Sciences at the meeting held on April 24, 2020 (Protocol No. 2020/З-04). Appropriate ethical permission was also obtained from the EMJJ ENT Hospital. Nasal mucosal tissue samples were collected from surgically resected specimens of patients aged 20–45 years diagnosed with allergic and atrophic rhinitis. The mucosal specimens were processed at the Institute of Biomedical Sciences of the Mongolian National University of Medical Sciences. Samples were fixed and dehydrated according to the protocol, coated with 100 Å gold, and examined using a scanning electron microscope (FEI Quanta FEG 250, USA). In addition, paraffin blocks were prepared, sectioned at 4 μm thickness, stained with Hematoxylin and Eosin, and analyzed histologically. Results: In allergic rhinitis, the pseudostratified epithelium was relatively preserved; however, disorganization of ciliated cells, partial loss of cilia, and goblet cell hyperplasia were observed. In contrast, atrophic rhinitis showed epithelial thinning, near-complete loss of ciliated structures, glandular atrophy, and submucosal fibrosis. Conclusion Allergic rhinitis is associated with relatively mild and predominantly functional mucosal alterations, whereas atrophic rhinitis demonstrates severe structural damage with irreversible impairment of mucosal protective function.

Background: Temporomandibular disorders (TMD) are the most common cause of non-dental orofacial pain and affect about one-third of adults. Population-based data obtained with standardized criteria are scarce in Mongolia, particularly outside the capital. Aim: To determine the prevalence of clinical signs of TMD and of examination-based Diagnostic Criteria for TMD (DC/TMD) diagnoses among residents of western Mongolia, and to compare them by sex and age group. Materials and Methods: This retrospective secondary data analysis utilized research data collected in 2020–2021 across Bayan-Ulgii, Govi-Altai, Zavkhan, Uvs, and Khovd aimags. A total of 520 participants were included in the analysis; participants aged from 16 to 71 years, with females accounting for 72.3%. Ethical approval for the secondary use of data was obtained in 2024. Diagnoses that can be established from the examination alone (IIa, IIIa–IIIc) were assigned. Differences were tested with chi-square and Fisher’s exact tests and logistic regression. The study was approved by the MNUMS Research Ethics Committee (№24/3-06) Results: At least one clinical sign was found in 87.1% of participants; deviation on opening (58.1%) and joint sounds (56.2%) were the most common. Muscle and joint pain on opening were found in 16.7% and 18.3%, and muscle and joint pain on palpation in 8.7% and 8.3%, respectively. An examination-based diagnosis was established in 21.5% (95% CI 18.2–25.3); disc displacement with reduction (14.4%) was the most common and Group III diagnoses were found in 8.3%. Pain on palpation at three or more muscle sites was found in only 3.3%. Compared with men, women more often had joint pain on opening (21.0% vs 11.1%; p=0.009) and muscle and joint pain on palpation, and had 2.5-fold higher odds of a Group III diagnosis (OR 2.50; 95% CI 1.02–6.15). Muscle pain on opening decreased with age (from 26.7% to 10.6%; p=0.036), whereas diagnoses did not differ by age group. Conclusions Most residents of western Mongolia had at least one clinical sign of TMD, mainly deviation on opening and joint sounds, and one in five had an examination-based DC/TMD diagnosis. Painful joint conditions were more common in women. The low prevalence of myofascial pain should be interpreted in light of limited standardization of palpation.

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: Sleep is a complex neuropsychological, biological, and physiological process essential to human health. Obstructive Sleep Apnea (OSA) is a highly prevalent disorder worldwide. In Asian countries, 12–40% of the population, and in the United States, 35.8% of the population are estimated to be at high risk for OSA. In Mongolia, however, there is limited research on the prevalence of OSA, which led to the initiation of this study. Aim: To determine the prevalence and risk level of OSA among the Mongolian population. Materials and Methods: A total of 1,405 individuals aged 18 and older from the clinical Mon-Timeline cohort study were assessed using the Berlin Questionnaire (BQ). The BQ evaluates three categories: snoring and witnessed apneas, daytime sleepiness, and high blood pressure and obesity. Individuals who met criteria in any two of the three categories were classified as being at high risk for OSA. Data on educational attainment and lifestyle behaviors were collected using the Food Frequency Questionnaire and the Global Physical Activity Questionnaire. Statistical analysis was performed using Student’s t-test, Pearson’s chi-square test (χ²), and ANOVA. Results: The mean age of participants was 42 ± 14.3 years, and 42.5% were male. A total of 24.3% (n=341) were found to be at high risk for OSA. The risk increased with age: 6.7% in individuals under 30, 28.3% in those aged 30–50, and 39.4% in those over 50. Participants at high risk for OSA tended to be older and more physically inactive. Additionally, 41.7% of all participants reported snoring, and 39.3% of those stated that their snoring disturbed others. Conclusion A significant portion (24.4%) of the Mongolian population is at high risk for OSA. These individuals are more likely to be older and physically inactive. The high prevalence of snoring and associated disturbances suggests a need for increased awareness, early detection, and age-targeted prevention strategies in Mongolia.

BACKGROUND OF STUDY: For the past 10 years, accidents and trauma are ranking third in the cause of Mongolian population’s death. Russian scientists have defined that skull and brain trauma comprise of 40% of the total traumas and is one of the serious injuries that have damaging effect to the health. Defining its creation, injury period, death cause in the leading direction of science of forensic medicine in our country are still the urgent issues. Nowadays little research which studied case mortality due to accident and trauma has been studied, this became background of our research work. PURPOSE OF STUDY: To study cause and peculiarity of pathology of case mortality due to brain trauma, in the condition of our country and to consider the result. OBJECTIVE OF STUDY: To study the cause, some risks of head injury. To define pathology of case mortality due to head injury. MATERIAL AND METHODOLOGY: We did retrospective study in 555 case material of an autopsy of case mortality of head injury of forensic medicine and research department of national institute of forensic science. Statistical work out was done by Microsoft excel and extensive index. RESULT OF STUDY: 84.5% (n=459) is male and 15.5% (n=86) is female out of our 555 involved cases and the gender ratio is 5:1. The most or 81% of the research participants had head injuries due to hitting with firm and dull stuffs and 15.9% head injury as a result of traffic accident follows in the second place. To analyze from the characteristics of mortality, 93% is subarachnoid hemorrhage, subdural, epidural hematoma, 64% is brain tissue injury were detected. CONCLUSION: Young manhood men mortality that has head injury resulted from the firm and dull things occupies most of the percentage in our research. The head injury can lead to the mortality of his ordinary process.

INNOVATION DENT • VOL. 3 • No.1 • Mar 2017 35 Background Odontogenic infection is defined as most dangerous inflammatory diseases in dental practice, it is believed that the cause of tooth decay disease and its complications currently a major cause of oral infections, or bacterial infection of the main sources of these diseases. Methods Between 2010-2011, odontogenic cellulitis in 21 patients were studied for aerobic and anaerobic bacteria by the Clinic bacterial laboratory in NCCD. Results 21 patients participated, were 10 men and 11 women with odontogenic cellulitis. Aerobic bacteria only were recovered in 3 (14%), anaerobic bacteria were recovered 8 (38%), mixed aerobic and anaerobic bacteria were recovered in 10 (48%). Conclusion A certain percentage of aerobic and anaerobic bacteria in odontogenic cellulitis shows simple space infection caused by aerobic bacteria, other complication of odontogenic cellulitis and multiple spaces infection caused by anaerobic and mixed bacterial infection. During dontogenic cellulitis determined high percentage of anaerobic and mixed bacterial infection, thus is our study have shown detection of anaerobic bacterial infection is important clinical significance in dental practice.

Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.
Animals ; Bias (Epidemiology) ; Birds ; Far East ; Geese* ; Lakes ; Mastication* ; Mongolia ; Phthiraptera* ; Population Density ; Prevalence

Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.
Animals ; Bias (Epidemiology) ; Birds ; Far East ; Geese* ; Lakes ; Mastication* ; Mongolia ; Phthiraptera* ; Population Density ; Prevalence