EXTRACTION, CHARACTERIZATION, AND ANTIMICROBIAL ACTIVITY OF F7 BIOSURFACTANT FROM BACILLUS CLAUSII AGAINST ORAL PATHOGEN KEY PLAYERS Introduction: Biosurfactants are surface-active molecules produced by various microorganisms. It holds exceptional properties, including its capacity to lower surface tension, antiadhesive activity, non-toxicity, biodegradability, and antimicrobial activity. Objectives: This study investigated the production, characteristics, and antimicrobial potential of biosurfactants extracted from Bacillus clausii, isolated from a crude oil sample obtained from a natural oil reservoir. Methods: Biosurfactant was extracted using the chloroform-methanol extraction method. Characterizations were assessed through Fourier-Transform Infrared Spectroscopy (FTIR), determination of surface tension, Critical Micelle Concentration (CMC), and emulsification index. Antimicrobial activity was determined by the Minimum Inhibitory Concentration (MIC) evaluation against Streptococcus mutans ATCC 25175, Enterococcus faecalis ATCC 24212, and Candida albicans ATCC 14503 using the microdilution method. Results: The biosurfactant extraction yielded at 1.6 mg mL-1, and was labelled as F7 biosurfactant. FTIR analysis revealed that the F7 biosurfactant belonged to the lipopeptide group, as evidenced by the presence of an aliphatic chain (CH3 and CH2). It exhibited a surface tension of 12.0 mN m-1, a CMC of 157.5 mg L-1, and an emulsification index of 56.5%. The MIC for each tested organism was 0.2 mg/mL-1, 0.4 mg/mL-1, and 0.8 mg/mL-1 with inhibition percentages of 3.20%, 4.03%, and 7.87% against S. mutans, E. faecalis, and C. albicans, respectively. Conclusions: The antimicrobial activities of the F7 biosurfactant demonstrated dose-dependent. These findings suggest that increasing the F7 biosurfactant concentration could lead to a more effective antimicrobial effect, making it a potential antimicrobial agent for oral applications.

This study is aimed to provide an insight into the types of treatment carried out by postgraduate students in the past 10 years. A retrospective study was carried out between November 2019 and February 2020 by deriving data from postgraduate students’ clinical logbooks of three different cohorts of Master of Clinical Dentistry (Restorative Dentistry in Conservative Dentistry) in 2010, 2013 and 2016. This retrospective data was systematically extracted from the records and tabulated categorically using an Excel spreadsheet (Microsoft Office Excel 2019). A descriptive analysis was carried out to further evaluate the results. Overall, the types of treatment carried out in the field of endodontics and fixed prosthodontics has changed in the past 10 years. An increasing trend is seen in the placement of all ceramic crowns and primary root canal treatment procedures, while a decreasing pattern is evident for secondary root canal procedures and placement of dental bridges.

Aesthetic or cosmetic dentistry is one of the main areas of dental practice. Increasing demands of patients for aesthetics has resulted in the development of several techniques for restoring the anterior teeth. Composite resin restorations have become an integral part of contemporary restorative dentistry and can be called “star of minimal invasion” due to its conservative concepts. The direct composite veneering allows restoring the tooth in a natural way and preservation of sound tooth structure when compared to indirect restorations. Before placement of direct composite veneers, a proper diagnosis, available treatment options, cost of treatment, patient’s expectations and duration of treatment should be taken into consideration. This article presents three case reports of aesthetic rehabilitation of anterior teeth using direct composite with satisfactory outcome that mimic the natural dentition.