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Background Coronavirus disease 2019 (COVID-19) emerged in China in December 2019. The COVID-19 pandemic hindered dental education, as school buildings were closed. Online dental teaching provided an alternative teaching tool for dental education. However, the efficiency of online dental teaching and student preferences for online dental teaching are unclear. Aim To investigate the satisfaction with online dental teaching practices among undergraduate dental students and standardized resident physician training students during the COVID-19 pandemic in China. Methods A total of 104 undergraduate dental students and 57 standardized resident physician training students from Zhejiang University participated in the study. A 12-item survey was conducted. This investigation included the teaching methods received, frequency of classes, degree of satisfaction, preferred teaching method, whether to participate in a course regarding COVID-19 prevention, and the effects of teaching. The percentages were then calculated and evaluated for each item. Results A total of 161 students (104 undergraduate dental students and 57 standardized resident physician training students) participated in this survey. All students had online dental classes during the COVID-19 pandemic. Lecture-based learning (LBL), case-based learning (CBL), problem-based learning (PBL), team-based learning (TBL), and research-based learning (RBL) were selected as teaching methods. Students were more satisfied with LBL and CBL than PBL, RBL, and TBL. The majority of students had more than four classes per week. The most selected protective measures were hand washing, wearing masks, and wearing gloves. A total of 46.6% of students participated in courses on COVID-19. After training, the students consciously chose to wear face shields and protective clothing. Conclusions Dental students accepted online dental learning during the COVID-19 pandemic. Students preferred LBL and CBL and were satisfied with the classes. Courses on COVID-19 helped students understand how to prevent COVID-19 transmission in the dental clinic.

A new peptide scaffold was made by mixing pure RADA16 (Ac-RADARADARADARADA-CONH2) and designer peptide RGDA16 (Ac-RADARGDARADARGDA-CONH2) solutions, and investigate any effect on attachment, spreading and proliferation of pre-osteoblast (MC3T3-E1). The peptides, RADA16 and RGDA16, were custom-synthesized. They were solubilized in deionized water at a concentration of 10 mg/ml (1% w/v), the RGDA16 peptide solution was mixed 1:1 with RADA16 solution and a new peptide solution RGDAmix was produced. The RGDAmix and RADA16 solution were directly loaded in 96-well plates and cover slips, and two different peptide scaffolds were formed with the addition of maintenance medium (alpha-MEM) in several minutes. About 1.0 x 10(4) MC3T3-E1 cells were seeded on each hydrogel scaffold, and then the cell morphological changes were observed using a fluorescence microscope at 1 h, 3 h and 24 h timepoint, respectively. Cell attachment was evaluated 1 h, 3 h and 24 h after cell seeding and cell proliferation was determined 4d, 7d and 14d after cell seeding. The RGDAmix scaffold significantly promoted the initial cell attachment compared with the RADA16 scaffold. MC3T3-E1 cells adhered and spread well on both scaffolds, however, cells spread better on the RGDAmix scaffold than on the RADA16 scaffold. Cell proliferation was greatly stimulated when cultured on RGDAmix scaffold. The RGD sequence contained peptide scaffold RGDAmix significantly enhances MC3T3-E1 cells attachment, spreading and proliferation.