Knowledge, attitudes, and practices of dentists after the COVID-19 pandemic: A cross-sectional study.

Background: Dentists are at an increased risk of encountering cross-infections because of working in close proximity with oral mucosa and saliva making use of high-speed rotary instruments during treatment generating large amount of aerosols and splatter which in turn increases the probability of nosocomial spread of infections. The present study aimed to evaluate the knowledge, attitudes, and practices of dentists after the COVID-19 pandemic. Materials and Methods: The present cross-sectional study was conducted using Google Forms wherein a well-structured questionnaire composed of a total of 25 closed-ended questions was distributed among practicing dentists through online mode. Step-wise linear regression analysis was done to determine the influence of independent variables on the knowledge, attitude, and practice scores of the participants. P < 0.05 was considered statistically significant. Results: On analyzing the results, multiple linear regression analysis revealed no significant difference in the knowledge scores among the participants, while good attitude and practice scores were significantly associated with higher qualification of the participants. Another noteworthy finding in the study was the significant correlation observed between the various components of the knowledge, attitude, and practice scores among the participants (P < 0.05). Conclusion: It could be concluded from the findings of the present survey that dentists were found to have good knowledge scores about the COVID-19 pandemic. They should, however, pay more emphasis on practicing tele-triaging and proper screening and should follow various guidelines and advisories issued from time to time by the competent authorities.

Comparative evaluation of impact strength of mechanically modified heat polymerized polymethyl methacrylate (PMMA) resin with addition of 0.5, 1, 2 wt% of silver nanoparticles (AgNPs): An in-vitro study.

OBJECTIVE: Polymethyl methacrylate (PMMA) is one of the most widely used denture base material because of favorable esthetics and desirable characteristics such as easy handling. Acrylic resins, although, have some inherent disadvantages such as relatively poor physical and mechanical properties. The objective of the present study was to evaluate and compare the impact strength of unmodified and modified heat cure PMMA-based denture base material with addition of different concentrations of silver nanoparticles (AgNPs) (0.5, 1, 2 wt%). METHODS: The present in-vitro study comprised of a total of 60 samples allocated to four groups with Group A samples consisting of heat cure acrylic resin without any modification (used as control); Group B samples consisting of heat cure acrylic resin modified with 0.5 wt% of AgNPs; and subsequently, Group C and Group D samples consisting of heat cure acrylic resin modified with 1 wt% and 2 wt% of AgNPs, respectively. The impact strength of the prepared acrylic samples was evaluated using Izod/Charpy Impact Tester, while the values obtained were tabulated and subjected to statistical analysis. Statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA), while one-way analysis of variance and Tukey's multiple post-hoc procedures were used for statistical analysis. P < .05 was considered statistically significant. RESULTS: The highest impact strength was found in Group C samples consisting of heat cure acrylic resin modified with 1 wt% of AgNPs to be closely followed by Group B samples consisting of heat cure acrylic resin modified with 0.5 wt% of AgNPs. Group D samples consisting of heat cure acrylic resin modified with 2 wt% of AgNPs, although, revealed relatively lower impact strength compared to Group B and Group C samples. CONCLUSIONS: Within the limitations of the present study, it was concluded that the impact strength of mechanically modified heat polymerized PMMA resin was significantly enhanced with addition of varying concentrations of AgNPs, although, it was observed that with an increase in the concentration of AgNPs, a subsequent decrease in the tensile strength of the final polymer material was observed.

Artocarpus hirsutus Lam Leaf Extract-Evaluation of Analgesic and Anti-Inflammatory Activity.

The study involved extraction, identification, and evaluation of pharmacological activities of the phytochemicals present. Artocarpus hirsutus Lam, commonly known as Wild jack is a greatly valued medicinal plant, which belongs to the plant family Moraceae. Preliminary phytochemical screening studies indicated the presence of flavonoids, saponins, tannins, glycosides, and alkaloids. This study estimated the analgesic and anti-inflammatory prospective of ethanolic leaf extract of Artocarpus hirsutus Lam. The findings showed that at various doses of 100, 200, and 400 mg/kg body weight when administered orally to rats, analgesic effects were produced, also the anti-inflammatory effect studied by carrageenan-induced rat paw edema test showed major anti-inflammatory action. The result indicates that the leaf extract of Artocarpus hirsutus Lam possesses major analgesic and anti-inflammatory activity and therefore requires further investigations to better understand the mechanism of action.

Isolation, Production, and Characterization of Serum Immunoglobulin M (IgM) of Indian Major Carp Cirrhinus mrigal (MRIGAL).

A method for the isolation of immunoglobulin M (IgM) in Indian major carp Cirrhinus mrigal (mrigal) serum to produce polyclonal antibodies is described in the present study. The purified immunoglobulins (IgM) were isolated from the serum of mrigal (Cirrhinus mrigal) by the bovine serum albumin (BSA)-CL affinity column purification method, and the IgM was used to produce a polyclonal rabbit anti-mrigal IgM antiserum. The IgM preparations were employed in the characterization of mrigal serum immunoglobulin. Reduced mrigal IgM on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was shown to consist of two subunits, compatible with heavy and light chains. A single heavy chain at approximately 90 kDa and variant of light chain 30 kDa were found. The dominant form of nonreduced IgM had a MW of approximately 900 kDa, suggesting a tetrameric structure based on estimated molecular weights, the relative protein content, and the reactivity with anti-mrigal IgM antisera, was obtained. The antisera were characterized as to specificity and reactivity by means of the enzyme linked immuno-sorbent assay (ELISA) and western blotting method. The information on the structure and character of immunoglobulin of fishes is essential in health management. The study described here investigates the possibility of using the serological techniques to assess the reactivity of antibody with the anti-mrigal IgM antisera.

The "Butterfly Effect" and Its Correlation to the Direction of the Fracture Line in Root Dentin.

INTRODUCTION: The butterfly effect is an optical phenomenon and is related to the presence of sclerotic dentin in the roots. The unique pattern of sclerotic dentin formation produces a characteristic butterfly shape in transverse sections of the roots. The objective of this study was to evaluate the direction of the fracture line in roots that exhibit the butterfly effect. METHODS: Thirty single-rooted premolars with oval-shaped roots were decoronated and embedded in acrylic blocks and subjected to vertical force under a universal testing machine (HPBSD; Tec-Sol India, Chennai, India). Fractured roots were examined under a stereomicroscope (Model no. 080772; Lawrence and Mayo, Mumbai, India) at ×10 magnification to determine the location and direction of the fracture line. To evaluate the correlation between the direction of sclerotic dentin and the direction of the fracture line, teeth were sectioned and observed under a stereomicroscope at ×20 and ×40 magnification. The correlation was analyzed using the Fisher exact test (P < .05 for the coronal and apical thirds and P > .05 for the middle third). RESULTS: Sclerotic dentin was observed more in the apical area and less in the coronal third of the root. The correlation between the direction of sclerotic dentin and the direction of the fracture line was statistically significant in the coronal and apical thirds of the root. CONCLUSIONS: The vertical root fracture that runs buccolingually is correlated to the harder sclerotic dentin present in the mesiodistal direction.

Comparative evaluation of the pushout bond strength of two root-end materials: An in vitro study.

AIM: The aim of this study is to evaluate the pushout bond strength of two bioceramic materials, two component calcium trisilicate material (biodentine), and premixed calcium trisilicate putty (Endosequence root repair material-fast set putty). SUBJECTS AND METHODS: 20 maxillary incisors were used in the study. Apical sections of 3mm were obtained and retro cavities to a depth of 3mm were prepared using a straight fissure bur. Another transverse section was made 4-mm coronal to the previous section. The specimens were placed into acrylic resin rings and separated into two groups and their cavities filled with the materials. The pushout test was carried out using a universal testing machine at a cross head speed of 0.5 mm/min, and the specimens were examined in a stereomicroscope at to evaluate the modes of failure. STATISTICAL ANALYSIS: The pushout bond strength values were analyzed using the unpaired t-test, and the modes of failure were compared using Fisher's exact test. RESULTS: The pushout bond strength was seen to be significantly higher (P < 0.001) for the two-component calcium trisilicate material (11.596 ± 3.309). Cohesive failure patterns were observed in both the test groups. CONCLUSION: Two component calcium trisilicate material demonstrated higher bond strength values to apical dentine.