The effect of virtual simulation technology applied to undergraduate teaching of periodontal probing.

INTRODUCTION: The rise of virtual simulation technology and dental simulators has created a new pedagogical approach for undergraduate medical education. The purpose of this study is to evaluate the effect of virtual simulation (VS) technology on improving the students' comprehensive abilities in periodontal probing teaching in pre-practicum periodontology, such as increasing the accuracy of probing, tactile perception and performance on force control. MATERIALS AND METHODS: Twenty students were randomly selected among the fourth-year students and equally divided into VS technology teaching group (VS group) and traditional teaching group (TT group) by drawing half lots. One day later, students were required to probe the periodontal pathology model. The consistency rate between PD measurements and PD reference values, time consumption and final exam scores were recorded and statistically analysed using an unpaired Student's t test and p < .05 was considered statistical significance. Finally, questionnaires relating to teaching methods evaluation and the fidelity of the digital VS training system were distributed to students and teachers. RESULTS: VS group had a significantly higher consistency rate (72.976 ± 6.811%) than TT group (64.107 ± 4.988%, p = .004). To specify, the difference of consistency rates between the two groups in posterior teeth was larger than anterior teeth. Similarly, a larger difference was also found in proximal surfaces compared with buccal-lingual surfaces. As the pocket depth increased, the difference between the two groups increased too. These results indicated that VS is more efficient in complicated parts of periodontal probing teaching. In addition, students in VS group spent less time and gained a higher score than TT group (p < .05). The overall satisfaction rating in VS group was significantly higher than TT group. Lastly, teachers gave significant lower scores than students concerning the fidelity of VS system. CONCLUSION: Although there are much to improve, VS technology has obvious advantages in periodontal probing teaching in pre-practicum periodontology.

Study of SARS-CoV-2 transmission in urban environment by questionnaire and modeling for sustainable risk control.

Caused by SARS-CoV-2, COVID-19 has become a severe threaten to society and human health, its epidemic control emerges as long-term issue. A sustainable epidemic and environmental transmission risk control (SEERC) in urban area is urgently needed. This work aims to conduct a new investigation on the transmission risk of SARS-COV-2 as virus/hazardous material through various environmental medias, routes and regions in the entirely urban area for guiding the SEERC. Specifically, 5 routes in 28 regions (totally 140 scenarios) are considered. For a new perspective, the risk evaluation is conducted by the quantification of frontline medicals staffs' valuable experience in this work. 207 specialists responsible for the treatment of over 9000 infected patients are involved. The result showed that degree of risk was in the order of breath>contact-to-object>contact-to-human>intake>unknown. The modeling suggested source control as the prior measure for epidemic control. The combination of source control & mask wearing showed high efficiency in SEERC. The homeworking policy needed to cooperate with activity limitation to perform its efficiency. Subsequently, a new plan for SEERC was discussed. This work delivered significant information to researchers and decision makers for the further development of sustainable control for SARS-COV-2 spreading and COVID-19 epidemic.

Interleukin-25 regulates matrix metalloproteinase-2 and -9 expression in periodontal fibroblast cells through ERK and P38MAPK pathways.

Interleukin-25 (IL-25) has been recognized as a new member of the IL-17 family and implicated in various inflammatory pathology. We aimed to investigate the effects of IL-25 on the expression of matrix metalloproteinase-2 (MMP-2), MMP-8, and MMP-9 in periodontal fibroblast cells (PFCs), cell migration, cytoskeleton F-actin, and to explore the involved extracellular-regulated protein kinases (ERKs), P38 mitogen-activated protein kinase (P38MAPK) signaling pathways, and IL-17 receptor. To evaluate the expression of MMP-2, MMP-8, MMP-9, and F-actin, PFCs were treated by various doses of IL-25 (0, 20, 50, 100, and 500 ng/ml). Protein expression of extracellular metalloproteinase inducer (EMMPRIN) was also evaluated by western blot. Cell scratches experiment was performed to test the cell migration ability. ERK, P38MAPK, and Jun N-terminal kinase signal pathways and related expression of P-ERK and P-P38MAPK were examined after treatment of different doses of IL-25 and after treatment of inhibitors of ERK and P38MAPK. Immunofluorescence of MMP-2, MMP-9, and F-actin were evaluated after inhibitor treatment. IL-17RB small interfering RNA was used to examine the receptor of IL-25. IL-25 increased the protein expression of MMP-2 and MMP-9. MMP-8 and EMMPRIN expressions were not regulated by IL-25 in PFCs. Positive IF staining extended strongly from the central part to the whole cell. IL-25 mediated MMP-2, MMP-9, F-actin expressions and cell migration were regulated by P38MAPK and ERK pathways, and IL-17RB. SB203580 and U0126 blocked the effects of IL-25 through the inhibition of ERK, P38MAPK, P-ERK, and P-P38MAPK. The data indicate that IL-25 could regulate cell migration, MMP-2, and MMP-9 expression, but not MMP-8 expression, in PFCs. Moreover, the regulation effects were involved in ERK and P38MAPK pathways, and receptor IL-17RB.