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.

Serum ceruloplasmin as cancer marker in oral pre-cancers and cancers.

BACKGROUND AND AIM: Oxidative stress leads to a compensatory increase in levels of serum ceruloplasmin in patients with such imbalances. Greater than normal serum ceruloplasmin levels are noticed in numerous cancers including the leukemias and Hodgkin's lymphoma. The purpose of the present study was to estimate and evaluate the efficacy of serum ceruloplasmin levels as a potential biomarker in the early detection of oral potentially malignant epithelial lesions (PMELs) including leukoplakia, oral submucous fibrosis (OSMF), and oral squamous cell carcinoma (OSCC) patients. MATERIALS AND METHODS: The present observational study was conducted over a period of 2 years wherein 100 subjects aged between 18 to 60 years were divided into four groups with Group A consisting of 25 healthy controls, Group B and C with 25 patients each, clinically diagnosed with oral leukoplakia and OSMF and Group D with 25 patients clinically diagnosed and histopathologically proven OSCC. The patients were subjected to incisional biopsy after routine hematological investigation while the same sera samples were used for analysis of serum ceruloplasmin levels. STATISTICAL ANALYSIS USED: Comparison of serum ceruloplasmin levels between the groups was performed using one way analysis of variance (one way ANOVA) test while P < 0.05 was considered statistically significant. RESULTS: The mean serum ceruloplasmin levels were found to be 43.19 ± 1.90mg/dl in subjects of group A, 47.68 ± 1.51mg/dl in group B, 47.74 ± 1.45mg/dl in group C and 47.73 ± 0.74mg/dl in group D. Using one-way ANOVA, statistically significant variations were found in the values of mean serum ceruloplasmin levels in subjects of the four groups (F-value = 59.58, P = 0.0001). CONCLUSIONS: The observations of the present study revealed that serum ceruloplasmin levels were found to be raised in all 3 study groups including oral leukoplakia, OSMF and OSCC as compared to the controls while the results were found to be statistically significant.

Evaluation of Surface Roughness and Hardness of Newer Nanoposterior Composite Resins after Immersion in Food-Simulating Liquids.

INTRODUCTION: Restorative resins during their prolonged use are exposed to variety foods and beverages are subjected to wear, degradation, and staining resulting in failure of restoration and require replacement. This study is aimed to evaluate surface roughness and hardness of five commercially available posterior resin composites following exposure to various food-simulating liquids (FSLs). MATERIALS AND METHODS: Specimens were immersed in distilled water, ethanol, citric acid, and air and later examined using a profilometer, scanning electron microscope for the surface profiles. Hardness was measured by Vickers Hardness test. STATISTICAL ANALYSIS: Results were subjected to two-way ANOVA and Tukey's multiple Post hoc test. RESULTS: There were significant differences in results among the composite resin tested. Inter comparison between materials after treating with FSLs, clear fill majesty (CFM) and Z350 showed better hardness values under the influence of ethanol, followed by Ever X, Tetric Evo Ceram and Sure fill SDR. None of the composites were unaffected by air compared to FSLs. Citric acid had reduced the hardness of CFM and had caused surface roughness on Sure fill SDR and Tetric Evo Ceram. Distilled water reduced hardness of CFM and SureFil SDR. EverX was not affected by any of the FSL either in hardness or surface roughness properties. All composites showed surface irregularities in all media. Ethanol and water had almost similar effect on all composites. CONCLUSIONS: Differences in hardness and surface roughness are due to different composition of resin matrix and different filler particles in all composite resin material tested.

A case of a Dandy-Walker variant: the importance of a multidisciplinary team approach using complementary techniques to obtain accurate diagnostic information.

Dandy-Walker malformation is a rare abnormality of the central nervous system (CNS) with a reported incidence of 1 in 25,00-35,00 live births and a slight female predominance. It accounts for 1-4% of cases of antenatally detected hydrocephalus. Dandy Walker variant forms part of the spectrum of Dandy Walker malformation. It is characterized by partial agenesis of the vermis, resulting in communication between the fourth ventricle and the cisterna magna. Dandy Walker malformation demonstrates an enlarged posterior fossa, with high insertion of the torcula herophili, as well as other features. In the diagnostic workup, ultrasound is reliable and accurate for making the diagnosis. In utero, fetal MRI can be used to confirm the diagnosis and also to identify any associated abnormalities. In cases of termination of pregnancy, autopsy will offer the diagnosis and provide additional information to assess the risk for future pregnancies and to help in counselling the parents. Autopsy is considered the gold standard for accurate diagnosis of the fetal abnormality. We report the unexpected finding of complete absence of the cerebellum due to maceration at autopsy, even though it was clearly demonstrated (but abnormal) on the antenatal ultrasound scan and MRI, as well as on post-mortem MRI. To the best of our knowledge, this has not been reported previously. Our case demonstrates the relevance of MRI when approaching a post-mortem examination with CNS malformation, and indicates that the "gold standard" might not always be autopsy.

Juxtaposed half-cystines as disulphide bridged partners in protein tertiary structure.

Disulphide bridges involving juxtaposed half-cystines are observed in a number of protein three-dimensional structures analyzed from the Protein Data Bank. These disulphide bridges comprise a 'ring of 8-atoms' corresponding to Calpha1-C'-N-Calpha2-Cbeta2-Sgamma2-Sgamma1-Cbeta1-Calpha1 in the two half-cystines. The presence of such disulphide bridges introduces a 'bend' or 'kink' in the protein polypeptide chain.

Analysis of disulphide bond connectivity patterns in protein tertiary structure.

The analysis of disulphide bond containing proteins in the Protein Data Bank (PDB) revealed that out of 27,209 protein structures analyzed, 12,832 proteins contain at least one intra-chain disulphide bond and 811 proteins contain at least one inter-chain disulphide bond. The intra-chain disulphide bond containing proteins can be grouped into 256 categories based on the number of disulphide bonds and the disulphide bond connectivity patterns (DBCPs) that were generated according to the position of half-cystine residues along the protein chain. The PDB entries corresponding to these 256 categories represent 509 unique SCOP superfamilies. A simple web-based computational tool is made freely available at the website that allows flexible queries to be made on the database in order to retrieve useful information on the disulphide bond containing proteins in the PDB. The database is useful to identify the different SCOP superfamilies associated with a particular disulphide bond connectivity pattern or vice versa. It is possible to define a query based either on a single field or a combination of the following fields, i.e., PDB code, protein name, SCOP superfamily name, number of disulphide bonds, disulphide bond connectivity pattern and the number of amino acid residues in a protein chain and retrieve information that match the criterion. Thereby, the database may be useful to select suitable protein structural templates in order to model the more distantly related protein homologs/analogs using the comparative modeling methods.