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OBJECTIVE: To synthesize three experimental resin based composites (RBCs) out of a commercial preperation (Control) by impregnating into each a fixed weight (0.01%) of titanium dioxide (TiO2) and three different weight % (0.01, 0.02 and 0.03) of proanthocyanidin (PA) and to compare antibacterial property, from the zones of inhibition of streptococcus mutans (S. mutans), of the specimen restorations made in the experimental and control RBCs. METHODOLOGY: In the first phase, Streptococcus mutans were isolated and identified from the oral cavity of patients and identified on the basis of morphogenic appearance of colonies and confirmed through catalase test and microscopic examination. Isolates were then incubated and cultured for sensitivity. Specimens for control and experimental RBCs were made through a metallic mold having 2mm thickness and 5mm diameter for all the 4 groups. Specimen restorations made in the commercial as supplied RBC acted as the control (Group A). Specimen restorations in the Group B, C, and D were made in each of the experimental RBCs modified with 0.01% proanthocyanidin (PA) and 0.01% titanium dioxide (TiO2), 0.02% PA and 0.01% TiO2 and 0.03% PA and 0.01% TiO2. The antimicrobial property of all the specimen restorations in all the groups was evaluated by Bauer-Kirby (Disc Diffusion) method through the formation of zones of inhibition of S. mutans colonies on blood agar plates. Data were computed using SPSS version 21 for descriptive statistics and analyzed using one-way ANOVA with p value 0.05 taken as significant. RESULTS: The range of the zone of inhibition for specimen RBC restorations (N= 12) containing PA and TiO2 was 0.00 for Group A, 10-12mm for Group B, 12-14mm for Group C and 9-10mm for Group D. The mean inhibition zone for the experimental restoration specimens was 11±2mm for Group B, 12.7±1mm for Group C and 9.7±1mm for Group D compared to no inhibition zones (0.00 mm) with the control RBC Group A. The order of the inhibition zones from maximum to minimum was Group C > Group B > Group D > Group A. The differences between the mean values for the control and the experimental RBC restoration specimens were significant (p < 0.000). The specimen restorations in the Group D appeared under cured and could impact on their mechanical properties. CONCLUSION: Irrespective of the mentioned concentrations, impregnating PA and TiO2 rendered the RBC antimicrobial. RBC restorations made with the experimental RBC with 0.02% PA and 0.01% TiO2 proved relatively more effective in terms of antimicrobial effect. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the effect, on fracture toughness (KIc), of impregnating silver nanoparticles (AgNPs) and bioactive glass (BAG) in resin based composites (RBCs). METHODOLOGY: During the period from August 2016 to May 2018, this study was performed at Peshawar Dental College (Pakistan) and Montreal University (Canada), using; a commercial RBC and experimental RBCs with or without BAG content (5-15wt%), and AgNPs (0.009%). Standardized specimens (n=6) were made in each of five RBCs (G1-G5). AgNPs were synthesized and characterized by uv-vis spectroscopy. With universal testing machine, the KIc for RBCs specimens was computed. SEM and dynamic light scattering (DLS) was used to assess the size and form of the prepared silica. One-way ANOVA and Tukey post hoc test were used for data analyses. RESULTS: KIc values varied both within and between RBCs groups. The commercial RBC had highest mean KIc (G1=1.03+0.24). Mean KIc values for the experimental RBCs were; G2=0.69±0.14, G3=0.9±0.13, G4=0.9±0.14 and G5=0.69±0.13. The only RBC groups that had statistically significant variations between their mean KIc values were; G1-G2 (p=0.017) & G1-G5 (p=0.017). SEM and DLS analysis of synthesized silica particles having round shape and sizes of 0.9-1µm. Uv-vis spectroscopy of AgNPs showed round shape with size up to 20nm. CONCLUSION: The KIc of the experimental RBCs with BAG (5-10 wt%) and AgNPs (0.009%) was not significantly different than the commercial RBC. [ABSTRACT FROM AUTHOR]

Supervisor of postgraduate research and education must ensure that scholars are professionally developed and made competent not only in their respective fields but also come out as graduates out of the institutions as useful members of the society and role-models. So far, a supervision that ensures mutual respect and the observing of office hours for learning, meetings, seminars and work has been considered useful and important. The current Covid-19 outbreak in the entire globe has disrupted all educational activities to happen in the educational institutions and research laboratories. The declaration, as public health emergency of international concern (PHEIC) by the World Health Organization (WHO), of the Covid-19, has required all governments and communities to contain, prevent and control this dreadful virus and infection. In this regard, people including students and teachers at all levels, have been forced to observe social distancing and establish working from their homes. This unique working situation has created the need to use alternative approaches to teaching and monitoring of learning and research activities. This writing aims to elaborate upon some aspects of remote teaching and supervision of graduate students. It is hoped that it will provide useful guidance both for supervisors and their students. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic, in relation to dentistry has caused so much concern that we all have many themes to write on. We now see that most initial level patient-dentist interaction could occur through the use of tele-dentistry platforms and over a video connection and smart or conventional phone. Both dentists and dental healthcare workers (HCWs) and patients have fear of getting infected. [Extracted from the article]