Association between Child Abuse and Poor Oral Habits in Mongolian Adolescents.

(1) This study aimed to investigate the association between child abuse and oral habits in adolescents in Mongolia. (2) A cross-sectional survey was conducted with children and their caregivers in Ulaanbaatar, Mongolia. Parents of 770 children enrolled in two public schools in Ulaanbaatar, Mongolia, completed questionnaires regarding the physical and psychological abuse that their children were subjected to and the presence of poor oral habits (biting nails/lips/pens and bruxism). Multivariable Poisson regression models were fitted with adjustment for age, gender, age of the mother, parental education, family income level, birth order, and living status with grandparents. (3) Biting nails/lips/pens and bruxism were reported by 39.0% and 17.5% of the respondents, respectively. Biting nails/lips/pens was significantly associated with physical abuse but was not significantly associated with psychological abuse (prevalence ratio, PR [95% confidence interval, CI]: 1.44 [1.07-1.95] and 1.34 [0.98-1.83], respectively). However, bruxism was not associated with physical or psychological abuse (PR [95% CI]: 1.16 [0.77-1.77] and 1.04 [0.68-1.61], respectively). (4) Child abuse was associated with biting habits among Mongolian adolescents.

Perception and attitude of Mongolians on malocclusion.

Background/purpose: This study assessed the perception and attitude of Mongolians on malocclusion and compared the perceptions with researchers' perceptions on malocclusion, and this study aimed to determine factors influencing the self-perception of laypeople. Materials and methods: In addition, we evaluated the correlation between the subjective and objective perceptions of participants. In a random sample of 133 people (39.8% men and 60.2% women) aged 18-55 years, subjective perceptions were assessed using a questionnaire (oral aesthetic subjective impact scale), and objective perceptions were assessed using 10 intraoral frontal photographs of the aesthetic component of index of orthodontic treatment need (AC-IOTN) and six intraoral lateral photographs of the aesthetic component of lateral occlusion (AC-LO). Results: A significant association was observed between participants' self-perception and researchers' ratings (P < 0.001). The appearance of teeth was significantly correlated with participants' self-rating by using AC-IOTN and AC-LO. Most people (74%) believed that well-aligned teeth improve the overall facial appearance. Sex, monthly income, and education level significantly influenced the self-perception of participants on malocclusion. Conclusion: Patients' perception and attitude cannot be overlooked because they are some of the crucial aspects of the entire treatment.

Association between Smoking during Pregnancy and Short Root Anomaly in Offspring.

Short root anomaly (SRA) is a dental anomaly with short dental roots and its pathogenesis is poorly understood. This study investigated the association between maternal smoking during pregnancy and SRA in offspring. A survey was conducted on 558 children aged 8-16 years from two public schools in Ulaanbaatar, Mongolia. SRA was diagnosed using cases with a root-crown ratio of maxillary central incisors of ≤1.0. A questionnaire survey was conducted to assess maternal lifestyle habits. Multiple logistic regression was used to analyse the association between maternal smoking during pregnancy and SRA in offspring after adjusting for possible confounders. The prevalence of SRA in these children was 14.2%. Children whose mothers smoked from pregnancy to date were found to be 4.95 times (95% confidence interval [CI]: 1.65-14.79) more likely to have SRA than those whose mothers never smoked, after adjusting for possible confounders. Additionally, children whose mothers had been exposed to passive smoking during pregnancy were found to be 1.86 times (95% CI: 1.02-3.40) more likely to have SRA than those whose mothers had not been exposed to passive smoke. Our population-based study suggests that maternal and passive smoking exposure during pregnancy can affect tooth root formation in children.

Associations between Malocclusion and Oral Health-Related Quality of Life among Mongolian Adolescents.

Malocclusion may affect oral health-related quality of life (OHR-QoL), however, the previously detected associations were affected by confounding factors. We hypothesized that there is indeed an association between OHR-QoL and malocclusion and investigated in a population-based study of 420 Mongolian adolescents mean age: 12.6 (standard deviation (SD) = 1.09) years from two secondary schools, located in an urban and a suburban area. We randomly selected two classes from each school. The Index of Orthodontic Treatment Need (IOTN) was used to assess malocclusion. OHR-QoL was assessed using the Child Perceptions Questionnaire (CPQ). Multivariate analysis was used to determine whether malocclusion had an independent effect on OHR-QoL. Overall, the existence of any type of malocclusion was not significantly associated with CPQ results. However, increased overjet was significantly associated with oral symptoms (coefficient: 0.66, 95% CI: 0.14-1.19), functional limitations (coefficient: 0.62, 95% CI: 0.17-1.08), and social well-being (coefficient: 0.50, 95% CI: 0.06-0.93). Deep bite was also significantly associated with oral symptoms (coefficient: 0.54, 95% CI: 0.23-0.84) and functional limitations (coefficient: 0.45, 95% CI: 0.19-0.72). Although malocclusion per se was not significantly associated with OHR-QoL, specific types of malocclusion, i.e., increased overjet and deep bite, were associated with OHR-QoL.

Association between maternal education and malocclusion in Mongolian adolescents: a cross-sectional study.

OBJECTIVE: Malocclusion is a highly prevalent condition, affecting 20-60% of adolescents worldwide. Although its treatment is often expensive and unaffordable for disadvantaged individuals, few studies have examined the relationship between malocclusion and socioeconomic status. We investigated the prevalence of malocclusion among Mongolian adolescents and its association with maternal education in a community-based sample in Mongolia. DESIGN: Cross-sectional study. SETTINGS: 2 large secondary schools with different backgrounds in Ulaanbaatar, Mongolia. PARTICIPANTS: Complete dental casts of 557 randomly recruited Mongolian schoolchildren aged 11-16 years were evaluated using the Dental Health Component of the Index of Orthodontic Treatment Need to dichotomise orthodontic treatment requirements. Exclusion criteria were the presence of orthodontic treatment history and absence of maternal educational status. Questionnaires were administered to caregivers to assess socioeconomic status. Poisson regression analysis was performed to examine the association between malocclusion and maternal educational status. RESULTS: The prevalence of malocclusion requiring orthodontic treatment among all adolescents was 35.2% (95% CI 31.2 to 39.2). In the unadjusted analysis, the prevalence ratio (PR) for malocclusion was higher (PR=1.46; 95% CI 0.96 to 2.20) among adolescents of mothers with a high educational background than among those of mothers with a low educational background. After adjusting for covariates, the PR remained significantly higher (PR=1.72; 95% CI 1.06 to 2.82) among adolescents of mothers with a high educational background. Other socioeconomic status variables, including family income and the educational level of the father, showed no association with malocclusion. CONCLUSIONS: These findings suggest that malocclusion requiring orthodontic treatment in adolescents is more prevalent among children of mothers with high levels of education. Further studies are needed to clarify the behavioural factors and environmental circumstance that contribute to this.

Effect of angiotensin II receptor blocker on experimental periodontitis in a mouse model of Marfan syndrome.

Marfan syndrome is an autosomal dominant disease characterized by aneurysm and dilatation of the aortic root, tall stature, and ectopia lentis. These manifestations reflect excessive signaling of transforming growth factor beta (TGF-ß). Moreover, cases are frequently associated with severe periodontitis, which is a chronic inflammation of the gingiva, periodontal ligament, and alveolar bone. Recently, angiotensin II receptor blockers (ARBs) were discovered to be an effective drug class that can prevent aortic aneurysm and dilation in Marfan syndrome by inhibiting TGF-ß signaling. To investigate the effect of ARB on the progression of periodontitis, the application of a potent ARB, telmisartan, was examined in a mouse model of Marfan syndrome (MgΔ). Six-week-old male heterozygous MgΔ and wild-type mice were challenged with Porphyromonas gingivalis, which causes chronic periodontitis, with and without telmisartan application. After infection, alveolar bone resorption was measured by micro-computed tomography (µCT), and inflammatory cytokine levels were examined. Infection of Porphyromonas gingivalis induced alveolar bone resorption in both MgΔ and wild-type mice. The amount of resorption was significantly larger in the former than the latter. Immunoarray and enzyme-linked immunosorbent assay (ELISA) analyses demonstrated that interleukin-17 (IL-17) and tumor necrosis factor alpha (TNF-α) levels were significantly higher in infected MgΔ mice than infected wild-type mice. Telmisartan treatment significantly suppressed the alveolar bone resorption of infected MgΔ mice. Telmisartan also significantly decreased levels of TGF-ß, IL-17, and TNF-α in infected MgΔ mice to levels seen in infected wild-type mice. This study suggests that ARB can prevent the severe periodontitis frequently seen in Marfan syndrome.

Dilated capillaries, disorganized collagen fibers and differential gene expression in periodontal ligaments of hypomorphic fibrillin-1 mice.

The periodontal ligaments (PDLs) are soft connective tissue between the cementum covering the tooth root surface and alveolar bone. PDLs are composed of collagen and elastic system fibers, blood vessels, nerves, and various types of cells. Elastic system fibers are generally formed by elastin and microfibrils, but PDLs are mainly composed of the latter. Compared with the well-known function of collagen fibers to support teeth, little is known about the role of elastic system fibers in PDLs. To clarify their role, we examined PDLs of mice under-expressing fibrillin-1 (mgR mice), which is one of the major microfibrillar proteins. The PDLs of homozygous mgR mice showed one-quarter of the elastic system fibers of wild-type (WT) mice. A close association between the elastic system fibers and the capillaries was noted in WT, homozygous and heterozygous mgR mice. Interestingly, capillaries in PDLs of homozygous mice were dilated or enlarged compared with those of WT mice. A comparable level of type I collagen, which is the major collagen in PDLs, was expressed in PDL-cells of mice with three genotypes. However, multi-oriented collagen fiber bundles with a thinner appearance were noted in homozygous mice, whereas well-organized collagen fiber bundles were seen in WT mice. Moreover, there was a marked decrease in periostin expression, which is known to regulate the fibrillogenesis and crosslinking of collagen. These observations suggest that the microfibrillar protein, fibrillin-1, is indispensable for normal tissue architecture and gene expression of PDLs.

Marfan syndrome and its disorder in periodontal tissues.

Elastic system fibers are composed of two distinct elements, elastin, which is an amorphous component crosslinked in the core, and microfibril, localized in the periphery of elastin. As microfibrillar proteins, fibrillins, microfibril-associated glycoproteins (MAGPs), latent TGF-beta-binding proteins (LTBPs), microfibril-associated proteins (MFAPs), and fibulins are known. Fibrillin-1 is a major microfibrillar protein and characterized by calcium binding EGF-like (cbEGF) domain. Association between fibrillin-1 and TGF-beta is a recent topic of this field and this interaction is known to inactivate and target TGF-beta action. FBN1 encoding fibrillin-1 is a responsible gene for Marfan syndrome type 1 (MIM #154700), characterized by increased height and long limbs, ectopia lentis, and cardiovascular disorders, such as mitral valve prolapse and aortic dilation and regurgitation. Animal models suggest that the abnormal TGF-beta signaling is underlying as the pathogenesis of these conditions. Besides skeletal, ocular and cardiovascular conditions, severe periodontitis is frequently seen in affected patients. To clarify the unknown function of elastic system fibers in the periodontal ligament (PDL), PDL-cells were isolated from a Marfan syndrome type 1 patient who was with the severe periodontitis and had a mutation in one of the cbEGF domain of fibrillin-1. These results suggested that wild-type fibrillin-1 was required for the normal cell alignment and tissue architecture of PDLs. Evidences are now accumulated to suggest that fibrillin-1 is one of the molecule involved in the interaction between cell and extracellular matrix.