The effect of different calcium silicate-based pulp capping materials on tooth discoloration: an in vitro study.

BACKGROUND: Variation in the composition of calcium silicate-based pulp capping materials could influence the discoloration potential of some of these materials, thus affecting the color and aesthetic appearance of the coronal tooth structure. Furthermore, contact with blood if hemostasis is not fully achieved may enhance this discoloration for some materials. Therefore the aim of this study was to evaluate in vitro the color change of coronal tooth structure after placing various calcium silicate-based materials in the pulp chamber in the presence or absence of blood. MEHTODS: Maxillary extracted premolars (n = 144) were sectioned and the crowns were separated from the roots. Pulp chambers were prepared to a standard size and then the tested materials (GMTA Angelus, ProRoot WMTA, Biodentine, TheraCal, and TotalFill) were placed with saline or with blood. Color change was assessed by spectrophotometry; prior to and after material placement at different time intervals of 24 h, 1 week, 1 month, 3 months, and 6 months. Color change (ΔE) values were calculated and statistically analyzed. RESULTS: In the saline groups, Biodentine caused the least color change, while GMTA and WMTA caused the highest color change which were significantly different from the others (p < 0.001), TotalFill and TheraCal caused moderate changes. Adding blood increased the ΔE overall the tested materials to various degrees. Biodentine was the most affected by the blood, while MTA groups were the least affected, followed by TotalFill and then TheraCal. The increase in ΔE was significant over time up to 3 months, after which the increase was not significant. CONCLUSIONS: Overall, WMTA and GMTA caused the most severe discoloration. In saline, Biodentine caused the least discoloration, but it was the most affected by the presence of blood, although it still caused the least discoloration similar to that observed with TotatFill. TheraCal caused moderate discoloration but more than that caused by Biodentine and TotalFill.

Knowledge, Attitude, Behavior, and Stress Related to COVID-19 among Undergraduate Health Care Students in Jordan.

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.