[Oral health behavior and parental cognition of first-grade children in urban and suburban areas of Shanghai].

PURPOSE: To investigate oral health behaviors of first-grade school children and parents' cognition of oral health in urban and suburban areas of Shanghai, and to analyze and compare the differences between the two areas, so as to provide reference for formulating oral health intervention measures and oral health education. METHODS: A total of 3 312 first-grade school-aged children in Shanghai were included by cluster random sampling method. Relevant data were collected through questionnaire survey of parents' oral health and clinical oral examination of children. Chi-square test was used to compare the differences in oral health behaviors of children and parents' oral health cognition between urban and suburban area with SAS 9.4 software package. RESULTS: The proportion of children who brush their teeth more than twice a day in urban and suburban areas was 72.55% and 44.26%, and the proportion of children who brushed their teeth with fluoride toothpaste was 53.25% and 44.79%, respectively. Compared with the suburban area, the brushing habits of school-aged children in urban area were better, the difference was statistically significant(P＜0.05). In terms of medical habits, the proportion of children with no dental experience in urban and suburban areas was 26.99% and 44.08%, and the proportion of children with toothache in the past year was lower than that in the last dental visit, the difference was statistically significant (P＜0.05). In terms of parents' cognition and attitude towards oral health knowledge, parents in urban areas were more correct than those in suburban areas, with the average correct rate being 82.56% and 70.42%, and the difference was statistically significant (P＜0.05). CONCLUSIONS: There are regional differences in oral health behaviors of first-grade school children and parents' oral health knowledge between urban and suburban area in Shanghai. It is suggested that relevant government departments should strengthen oral health education and oral health behavior guidance for parents, and strengthen oral health investment in non-central urban areas.

Microbiota of preterm infant develops over time along with the first teeth eruption.

Objective: The temporal growth of the infant microbiome in the early years of life influences short- and long-term infant health. The aim of this longitudinal study was to investigate bacterial dynamics in the microbiome of preterm infants during tooth eruption. Methods: Saliva samples from normally delivered (n = 24) and preterm infants (n = 31) were collected 30 days after birth and after the eruption of two primary mandibular incisors. Based on Illumina MiSeq Sequencing of the 16S rRNA gene, the dynamic microbial changes of newborns at two-time points were investigated. Meanwhile, the Human Oral Microbiome Database was adopted for assigning taxonomy. Results: Using alpha and beta diversity analyses, different shift patterns of microbiome structures in preterm and healthy participants and bacterial diversity over time were observed. The relative abundance and shifts trend, along with the two lower primary central incisors eruption, of core oral flora varies in full-term and preterm groups, including Gemella spp., Rothia mucilaginosa, Veillonella atypica, etc. Several microorganisms colonize later in the oral microbiome development of premature babies, such as Gemella spp. In addition to teeth eruption, the growth of the saliva microbiome in preterm infants could be influenced by breastfeeding durations and birth weight. Conclusion: This study provided insights into how the oral microbiota changes during tooth eruption in preterm infants and how the colonization of the oral cavity with bacteria in preterm infants differs significantly from that in full-term infants.