Objectives This study aimed to assess knowledge, attitude, and infection control measures related to the coronavirus disease 2019 (COVID-19) pandemic outbreak among Jordanian health care students. Besides, their social behavior and stress level regarding COVID-19 infection were assessed. Materials and Methods An online questionnaire was distributed to medical, dental, pharmacy, nursing, and applied health science students in Jordan during the COVID-19 outbreak quarantine in March 2020. The questionnaire comprised 38 questions assessing demographic data, knowledge, attitude, risk perception, and stress level toward COVID-19. Questions regarding infection control measures and social behavior after the quarantine were also included. Statistical Analysis Independent samples t-test, one-way analysis of variance (ANOVA), and chi-square at a significance level of 5% were used for data analysis. Results A total number of 935 responses were collected. The knowledge score of 55.72% of participants was satisfactory and it was higher for the clinical years’ students compared with the basic years’ students (p = 0.000) (descending order: sixth year > fifth year > fourth year > third year > first year > second year). Also, knowledge scores were significantly higher for medical and dental students than other disciplines (descending order: medicine, dentistry, pharmacy, nursing/applied) (p = 0.000). The social media (89.1%) and TV or radio (69.5%) were mainly routes through which participants heard about COVID-19. Moderate and justifiable feelings about COVID-19 were found in the majority of the participants. Conclusion Although the majority of students showed good knowledge scores, few of them appeared to have a serious lack of knowledge. Therefore, proper education and mentoring are necessary for students before reopening the university campuses.

As antiviral vaccines are still pending for the COVID-19 disease, improving dentists’ knowledge and prevention measures is important. This study aimed to assess dentists’ knowledge, attitude, and perception of COVID-19 in Saudi Arabia during the early outbreak period. In addition, infection control measures for dental setting were also assessed. Online questionnaire was distributed to dentists in different regions of Saudi Arabia when COVID-19 outbreak in Saudi Arabia was at its beginning. The questionnaire was assessing demographic variables, knowledge, attitude, risk perception, and preparedness towards COVID-19. Questions regarding infection control measures were also included. The correct incubation period of the virus was recognized by 43% of participants. Fever, cough, and shortness of breath were the mostly recognized symptoms for COVID-19 (98.9%, 95.5%, and 93.3% respectively). Participants in age groups ≥60, 50–59, and 20–29 years old were more likely to perceive COVID-19 as a very dangerous disease compared to 30–39 and 40–49 age groups. Dentists in Saudi Arabia showed satisfactory knowledge and positive attitude towards COVID-19. Improving dentists’ level of knowledge could be achieved through increasing their accessibility to materials provided by dental health care authorities, which specifies the best and safest approaches for dealing with patients during and after the outbreak.

No abstract

This study aimed at assessing the performance of Reciproc Blue (RB) and XP Endo Shaper (XPS), used for canal retreatment on extracted teeth, in terms of debris extrusion and obturating materials removal. Thirty mandibular premolars were prepared to ProTaper X2 file, obturated using warm vertical compaction, and then incubated for 28 days at 100% humidity at 37°C. Teeth were randomly assigned into two groups, according to the system used for retreatment (RB and XPS). During retreatment, debris extruded beyond the apex was collected in preweighed Eppendorf tubes, and the retreatment time was measured. Afterward, the teeth were longitudinally sectioned to assess the remaining obturating materials. Data were statistically analyzed using the Mann–Whitney test and chi-square test at a 95% confidence level. All the samples had extruded debris at varying weights ranging from 0.125 mg to 3.680 mg. XPS extruded less debris than RB, but no difference was detected (Mann–Whitney test; P > 0.05 ). RB and XPS required 54.9 ± 17.9 and 22.3 ± 9.3 seconds to perform retreatment procedures, respectively (Mann–Whitney test; P < 0.05 ). The sealer was found in all the samples. Compared to the RB group, fewer samples with remaining gutta-percha were found in the XPS group (Chi-square test; P < 0.05 ). None of the files fractured during the retreatment procedure. The tested files appear to extrude debris beyond the apex. Although XPS was able to remove the gutta-percha completely from the majority of the canals, it was unable to remove the sealer.

BD had the highest solubility while IO had the least. The relatively stable polymeric resin in IO may contribute to its low solubility but high hygroscopic expansion. Desiccation had significant effect on sorption, solubility and volumetric expansion of water-based materials.