Jiahan Peng

Recurrence remains a significant challenge following the treatment of Severe Early Childhood Caries (S-ECC). This study aimed to identify candidate recurrence-related biomarkers for S-ECC and elucidate their potential pathogenic mechanisms. Through metagenomic sequencing of supragingival plaque from 32 children at one month post-treatment, we identified Leptotrichia hofstadii as one of the potential biomarkers for S-ECC recurrence (AUC = 0.8438 for the sequencing set and AUC = 0.75 for the validation set). In vitro dual-species biofilm assays using crystal violet staining and Confocal Laser Scanning Microscopy (CLSM) demonstrated that L. hofstadii promotes early-stage S. mutans colonization and extracellular polysaccharide (EPS) formation through contact-dependent synergistic interactions. Scanning electron microscopy revealed that L. hofstadii may function as a spatial scaffold within dual-species biofilm. Furthermore, this synergy significantly accelerates environmental acidification, leading to earlier attainment of the critical demineralization threshold (pH 5.5). At the transcriptional level, carbohydrate metabolism-related pathways were upregulated in dual-species biofilm, including starch and sucrose metabolism, PTS and ABC transporters. Additionally, the fruA gene, which degrades fructan in EPS was downregulated in the dual-species biofilm compared with S. mutans monoculture. These findings suggest that L. hofstadii facilitates a cariogenic microenvironment by enhancing the metabolic activity of S. mutans biofilms. Collectively, this study identifies L. hofstadii as a potential biomarker for S-ECC recurrence prediction and provides preliminary insights into possible interspecies mechanisms, offering valuable clues for future research into targeted preventive strategies.

The differences in microbiota between periodontitis and health have been extensively studied; however, knowledge about how the microbiota shifts from shallow to deep periodontal pockets remains limited despite its clinical importance in disease progres-sion and management. Patients diagnosed with stage III periodontitis commonly pre-sent varied probing depths (PD) within the same oral cavity, reflecting localized disease severity. This study aims to analyze the microbiome of subgingival plaques at various PDs in periodontitis patients. Subgingival plaques were collected from sixteen healthy subjects (health group) and periodontal pockets of sixteen stage III periodontitis pa-tients (PD 0–3 mm, PD 4–5 mm and PD 6–9 mm groups). A total of 64 subgingival plaque samples underwent 16S rRNA gene sequencing. The PD 6–9 mm group exhib-ited significantly higher alpha diversity than the health group, and distinct subgingival microbial community structures were observed in periodontitis patients, regardless of probing depth. The relative abundance of specific genera differed notably between health and periodontitis states; Corynebacterium and Cardiobacterium decreased, whereas Schaalia increased in shallow pockets (PD 0–3 mm) of periodontitis relative to the health group. Co-occurrence network analysis on the species level revealed that the PD 4–5 mm group had the most complex interspecies interactions, followed by the PD 6–9 mm and PD 0–3 mm groups. These findings indicate significant variations in mi-crobial diversity, composition, and interspecies interactions associated with periodon-tal health and periodontitis severity, highlighting their potential relevance for clinical diagnosis and targeted therapeutic strategies.

Background/Aim: The aim of this study was to investigate the impact of traumatic dental injury (TDI) on oral health‐related quality of life (OHRQoL) of preschool children, and further inform public oral health care policies and strategies for this age group TDI patients. Materials and Methods: This retrospective and cross‐sectional study was conducted in the Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China. It included 314 children aged from 2 to 5 years, with 90 children diagnosed with TDIs and 224 without TDIs. Parents or primary caregivers completed questionnaires, and the responses were gathered for statistical analysis to evaluate the impact of TDIs. The OHRQoL was assessed using the Early Childhood Oral Health Impact Scale (ECOHIS). Results: The total ECOHIS score and the scores for the 13 individual items were significantly higher in children with TDIs compared with those without TDI ( p < 0.001). In the child impact section, eating and masticatory function were the most severely affected (40%), while most of parents experienced strong feelings of self‐blame in the family impact section (61.1%). A positive correlation was observed between the number of injured teeth and the total ECOHIS score ( p = 0.001), while the time elapsed since TDI indicates a negative correlation with the total ECOHIS score ( p < 0.001). Additionally, children with severe TDIs had higher ECOHIS scores than those with mild TDIs, indicating a greater impact on OHRQoL ( p = 0.006). In contrast, tooth discoloration, the caregiver's relationship to the child, caregiver education level and the position of the affected teeth did not significantly influence the total ECOHIS score ( p > 0.05). Conclusions: TDIs have a significant impact on OHRQoL in preschool children, highlighting the need for greater societal attention. Strengthening preventive and proper treatment measures for TDIs, along with enhancing health education programs, is strongly recommended.