OBJECTIVETo investigate the acquaintance to orthodontics and possible factors that obstruct orthodontic treatment in middle school students in zones with different economic levels in Jiangjin, Chongqing.

METHODSThe students were randomly divided into four groups: A class from a junior high school in town (group 1), a class from a senior high school in town (group 2), a class from a junior high school in the countryside (group 3), a class from a senior high school in the countryside (group 4). The information was collected by questionnaire, and the statistical analysis of results was carried out by SPSS 17.0 software.

RESULTSSex made difference in the acquaintance to orthodontics treatment. Girls worried more about teeth extraction and pain that may occur during treatment than the boys. Students in the city had more access to related consultations compared to those in the countryside. Different economic conditions made much contribution to the proportion to go for orthodontics treatment in cities and rural areas. The evaluation from families and friends may affect patients' subjective estimation to themselves.

CONCLUSIONOrthodontists should learn more about student patiens from various aspects, and make different therapies according to their sexes, economic conditions of family, education levels, etc. Only so can orthodontists get better compliance from their patients.

Adolescent ; Female ; Humans ; Male ; Orthodontics ; Students

Objective:To study the expression of zonula occludens-1(ZO-1) in neonates with necrotizing enterocolitis (NEC) and to explore the effects of disialyllacto-N-tetraose (DSLNT), a compound extracted from human milk, on the intestinal barriers in rat model of NEC.Methods:(1) Human study: From Feb 2013 to Dec 2020, the pathological samples of ileum tissue from 21 neonates (12 patients with NEC and 9 with intestinal atresia) from Pathology Department of our hospital were collected. The expressions of ZO-1 in these samples were examined using immunohistochemistry (IHC) method. (2) Animal study: A total of 28 newborn rats were randomly assigned into control group ( n=8), NEC group ( n=10) and DSLNT+NEC group ( n=10). Experimental NEC model was established based on hypoxia (95%N 2 10 min) /cold exposure (4 ℃ 10 min) three times a day for consecutive 3 days. DSLNT+NEC group were fed with formula+DLSNT (300 μmol/L) during hypoxia/cold exposure. All the surviving rats were sacrificed at the end of the experiment (72 h) and the terminal ileum tissues were collected. Hematoxylin-Eosin (HE) staining was used to evaluate tissue damage and Western blotting was used to determine the expressions of ZO-1. (3) Cellular study: Bacterial lipopolysaccharide (LPS) was used to establish a cellular inflammation model in human intestinal epithelial cell lines (Caco-2) and DSLNT (300 μmol/L) was applied to this model. Thiazolyl blue assay was used to examine cell viabilities and immunofluorescence assay was used to detect ZO-1 expression. The effects of DSLNT on cell growth and tight junctions of Caco-2 cells were analyzed. Results:(1)Human study: The villi of mucous layer of the lesion were damaged in NEC patients. ZO-1 expressions at the epithelial junction of NEC patients were decreased compared with intestinal atresia patients and non-lesion intestines of NEC patients. (2)Animal study: Apical extrusion, necrosis and shedding of epithelial cell were seen at the lesions in NEC group. The expression of ZO-1 in NEC group was significantly lower than the control group and DSNLT+NEC group ( P<0.05).DSNLT+NEC group had higher survival rates (8/10 vs. 6/10) and lower ileum inflammatory pathological scores [2.0(1.0, 2.8) vs. 3.5(3.0, 4.0)] than NEC group. (3) Cellular study: Caco-2 cells exposed to LPS showed inhibited cell growth and decreased ZO-1 immunofluorescence staining. Caco-2 cells in the DSLNT+LPS group showed better viability than LPS group and were comparable with the control group. The expression of ZO-1 was significantly increased in the DSLNT+LPS group. Conclusions:Tight junction injury of the intestinal epithelial cell is an important characteristic of NEC. ZO-1 is a potential target for the prevention and treatment of NEC. DSLNT may protect the neonatal intestines by modulating the expression of ZO-1 and keeping tight junction integrity.

Malocclusion is a worldwide dental problem that influences the affected individuals to varying degrees. Many factors contribute to the anomaly in dentition, including hereditary and environmental aspects. Dental caries, pulpal and periapical lesions, dental trauma, abnormality of development, and oral habits are most common dental diseases in children that strongly relate to malocclusion. Management of oral health in the early childhood stage is carried out in clinic work of pediatric dentistry to minimize the unwanted effect of these diseases on dentition. This article highlights these diseases and their impacts on malocclusion in sequence. Prevention, treatment, and management of these conditions are also illustrated in order to achieve successful oral health for children and adolescents, even for their adult stage.
Child ; Humans ; Malocclusion ; epidemiology ; etiology ; prevention & control ; Prevalence ; Stomatognathic Diseases ; complications ; epidemiology ; prevention & control