Oral fungal homeostasis is closely related to the state of human health, and its composition is influenced by various factors. At present, the effects of long-term soil heavy metal exposure on the oral fungi of local populations have not been adequately studied. In this study, we used inductively coupled plasma–mass spectrometry (ICP-MS) to detect heavy metals in agricultural soils from two areas in Gansu Province, northwestern China. ITS amplicon sequencing was used to analyze the community composition of oral buccal mucosa fungi from local village residents. Simultaneously, the functional annotation of fungi was performed using FUNGuild, and co-occurrence networks were constructed to analyze the interactions of different functional fungi. The results showed that the species diversity of the oral fungi of local populations in the soil heavy metal exposure group was lower than that of the control population. The relative abundance of Apiotrichum and Cutaneotrichosporon was higher in the exposure group than in the control group. In addition, Cutaneotrichosporon is an Animal Pathogen, which may lead to an increased probability of disease in the exposure group. Meanwhile, there were significant differences in the co-occurrence network structure between the two groups. The control group had a larger and more stable network than the exposure group. Eight keystone taxa were observed in the network of the control group, while none were observed in that of the exposure group. In conclusion, heavy metal exposure may increase the risk of diseases associated with Apiotrichum and Cutaneotrichosporon infection in the local populations. It can also lead to the loss of keystone taxa and the reduced stability of the oral fungal network. The above results illustrated that heavy metal exposure impairs oral fungal interactions in the population. This study extends our understanding of the biodiversity of oral fungi in the population and provides new insights for further studies on the factors influencing oral fungal homeostasis.

Growing evidence highlights the role of heavy metals in driving the co-selection of an-tibiotic resistance genes (ARGs), and the human oral cavity is an important reservoir of ARGs. This cross-sectional study investigated the effects of heavy metal exposure on human oral microbiota and ARGs, collecting buccal mucosal and blood samples from residents in a heavy metal-contaminated area (Baiyin City) and a non-contaminated area (Yuzhong County, Lanzhou City). The results showed heavy metal exposure is associated with altered alpha and beta diversity of bacteria and ARGs in human oral cavities, with bacterial compositional shifts being the main factor in ARG variation. Metagenomic analysis revealed heavy metal exposure is linked to modifying the interactions in the bacterial community and between ARGs and metal resistance genes (MRGs), shown by simplified topological structures in bacterial and resistome networks, along with enhanced positive correlations among nodes. Neisseria, Haemophilus, Morococcus, Streptococcus, Staphylococcus, and Mycobacteroides as potential hosts for resistance genes in human oral cavity. Furthermore, blood metal quantification revealed distinct associations with resistance patterns. This study demonstrates significant associations between environmental heavy metal exposure and the oral resistome and emphasizes the role of bacterial community composition.

Manual dexterity is fundamental to preclinical dental training, yet opportunities for standardized early psychomotor practice remain limited. This study evaluated changes in simulator-based manual dexterity task performance following a curriculum-embedded virtual simulation course for second-year undergraduate dental students. Ninety-nine students completed identical pre- and post-training assessments using the man001 three-dimensional tunnel module over a six-week course; during the intervening training period, students practiced other, more advanced manual dexterity modules. Ninety-eight students completed an anonymous post-course questionnaire. The mean total score increased from 79.94 ± 4.54 to 86.26 ± 3.60, with a mean paired difference of 6.32 points (95% CI, 5.29–7.36; p < 0.001; Cohen’s d_z = 1.22). Leeway decreased from 10.92 ± 4.53 to 4.96 ± 2.79 (p < 0.001), and container values also decreased (p < 0.001), whereas target performance did not change significantly (p = 0.169). Overall, 92.93% of students improved their total score. Most respondents reported active engagement (94.90%), considered the course helpful (96.94%), and perceived it as clinically relevant and supportive of theory–practice integration (98.98%). The six-week course was associated with short-term changes in man001 simulator-task performance and predominantly favorable student perceptions; further research is needed to explore the retention of these changes and their transfer to broader manual dexterity and physical preclinical procedures.