Evaluation of Antimicrobial and Mechanical Properties of a Novel Propolis-Modified Orthodontic Primer: An In-Vitro Study.

Introduction Accumulation of cariogenic biofilm around the bracket surface and the enamel adhesive interface leads to the formation of white spot lesions which poses an arduous challenge in orthodontics today. The aim of this study was to do a comparative evaluation of the antimicrobial, cytotoxic and mechanical properties of a novel propolis-modified orthodontic primer with a control primer. Materials and methods This in-vitro study involved two groups (group A: propolis-modified primer and group B: control primer). Antibacterial properties against Streptococcus mutans were evaluated using the agar well diffusion technique to measure the zone of inhibition and mic was evaluated using the two-fold diffusion technique. 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) fibroblast assay was done to evaluate the cytotoxicity. After bonding brackets on extracted natural teeth (premolars) the shear bond strength (SBS), contact angle (CA) and adhesive remnant index (ARI) were evaluated for both groups. Statistical analysis was done using Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 23.0, Armonk, NY), and an independent t-test was performed. Results The propolis-modified primer when compared to the control primer had higher zone of inhibition values and lower minimum inhibitory concentration (MIC) values. The MTT fibroblast assay showed that the cell viability % shown by the propolis primer was more than the control primer. There was no statistically significant difference between the two primers for SBS (p>0.05), CA (p>0.05) and ARI (p>0.05) (p=0.05). Conclusion The propolis-modified primer showed higher antibacterial activity against S. mutans at a lower inhibitory concentration, with less cytotoxicity and no effect on the SBS, CA and ARI scores.

Comparative Assessment of Bracket Bond Failure Rates of a Novel Chitosan-Based Orthodontic Primer: An In Vivo Split-Mouth Study.

Introduction An unavoidable side effect of orthodontic fixed appliance therapy is the demineralization of the enamel surface surrounding the bracket at the adhesive and tooth interface due to a microgap formation, which serves as a nidus for biofilm growth. Due to this, it is advantageous to include antibacterial agents in orthodontic primers without affecting their clinical properties. The aim of this study was to compare the in vivo bracket bond failure rates of a novel chitosan-based primer with a conventional orthodontic primer. Materials and methods Fifty-four subjects and 1,080 brackets were included in this study. At the end of six months, 45 subjects and 960 brackets bonded using novel chitosan-based primers and conventional primers (Anabond, Anabond Stedman Pharma Research Pvt Ltd, Chennai, India). Each was evaluated for a bracketed bond failure rate. Descriptive statistics and Chi-square tests were used for statistical analysis. Results The results revealed that the bracket bond failure rate in Group 1 (novel chitosan-based primer) was 27 brackets (3%) and 23 brackets in Group 2 (conventional primer) (2.5%), with no statistically significant difference between the two groups (p>0.05). There was a statistically significant difference in the bracket failure rate between the maxillary arch (2%) and the mandibular arch (3.5%) (p<0.05). Conclusion Brackets bonded with the chitosan-modified novel orthodontic primer showed no statistically significant difference in bracket bond failure rate when compared to the conventional primer. Bond failure rates were higher in the mandibular teeth when compared to the maxillary teeth.

Herbal-mediated preparation of nano-sized particles of selenium, its characterization, and evaluation of its antimicrobial activity.

This study aimed to synthesize selenium nanoparticles (SeNPs) using stevia plant leaves and to evaluate the antimicrobial effect of nano-sized particles of selenium. A new organic synthesis of nano-sized selenium particles was done in this study. In this study, stevia leaves for the synthesis of nano-sized particles along with sodium selenite were done. This mixture was mixed homogeneously using an orbital shaker overnight. The color change indicated the formation of SeNPs. The SeNPs were evaluated for their size and shape and their antimicrobial property was assessed. SeNPs showed excellent antimicrobial activity against Candida albicans at 100 µL concentration. At 25 µL and 50 µL, C. albicans showed intermediate susceptibility to SeNPs which also indicated a good antimicrobial potential. Following C. albicans, SeNPs showed good antimicrobial potential against Streptococcus mutans at all concentrations. SeNPs possessed good antimicrobial activity against most common oral pathogens.

Assessment of Wettability and Contact Angle of Bonding Agent with Enamel Surface Etched by Five Commercially Available Etchants: An In Vitro Study.

BACKGROUND: The quantity and quality of the etching pattern produced by acids play a significant role in the wettability and contact angle of the adhesive with the enamel surface in orthodontics. The better the etch pattern, the more the surface energy of the enamel, better the penetration of the adhesive, which ultimately results in better bond strength. The present study aimed to evaluate the contact angle of the bonding agent with the enamel surface etched by five commercially available etchants and check if any difference existed between the five. MATERIALS AND METHODS: Twenty-five human maxillary and mandibular central incisors and premolars extracted for orthodontic or dental purposes were used in this study as samples. The teeth were allocated into five groups based upon the etchant used to etch the enamel surface. After the samples were etched, a hard tissue microtome was used to create thin slices of the enamel surface. The samples were then exposed to bonding agent Ormco Enlight. The bonding agent was released in the form of droplets onto the enamel slices mounted on a contact angle goniometer. The contact angle values were tabulated, and statistical analysis using the one-way ANOVA test was carried out. RESULTS: The contact angle measurements of the etchant group, DPI, were the lowest, while D-tech has the highest contact angle values. However, statistical analysis revealed no statistically significant difference between the contact angle measurements of the five groups included in the study. CONCLUSION: No statistically significant difference existed between the five etchant groups included in the study. However, commercially available etchant DPI showed lesser contact angle and thus better wettability in comparison to other groups. Further elemental analysis and surface analysis are required to validate these results.