الفهرس | Only 14 pages are availabe for public view |
Abstract Aim: The aim of this study is to assess the effect of addition of a synthesized antibacterial quaternary ammonium (QA) compound and bioactive glass nanoparticles on the antibacterial properties and bioactivity respectively of the experimental dental adhesive system. Methodology: A QA compound was synthesized from 2-(Dimethylamino) ethyl methacrylate and 1- Bromobutane and characterized using CHN, FTIR and H+NMR analyses. The synthesized QA was assessed for its cytotoxicity using MTT assay, and its antibacterial activity using disc diffusion method, measurement of minimum inhibitory concentration and minimum bactericidal concentration, time kill test, and TEM imaging. The QA compound was added to the primer of a commercially available adhesive (Optibond XTR) by two concentrations 20 mg/mL and 40 mg/mL representing the MIC and MBC, respectively., while 5% bioglass fillers were added to the adhesive bottle. Then, the experimental adhesives were characterized by measurement of pH and degree of conversion. Comparison was made between the experimental adhesive, commercial antibacterial adhesive Clearfil SE Protect (CP) containing MDPB antibacterial monomer and fluoride fillers, and commercial vehicle (Optibond XTR) regarding antibacterial properties using time kill test, and bioactivity through quantifying Calcium and Phosphorus ion release using Inductive couple plasma, and observation of apatite formation by scanning electron microscope, followed by elemental analysis by EDX and calculation of Ca/P ratio. Statistical analysis by ANOVA followed by tukey post-hoc test (P˂0.05). Results: Disc diffusion and time-kill kinetics tests showed potent antibacterial properties of the synthesized QA compound against S. mutans both in the unpolymerized and the cured forms. MIC and MBC were 20 and 40 mg/mL respectively. There was no statistically significant difference between experimental adhesives and CP with more than 99% reduction in bacterial count, while OptiBond XTR showed no bacterial killing up for up to 10 hours. The experimental adhesive samples showed a statistically significant higher calcium release after 2 weeks than the control groups. The Ca/P ratio was statistically significantly higher on dentin discs with the experimental adhesive and the plain commercial adhesive compared to CP. Also, this ratio increased after 2 weeks follow up for all materials. SEM images revealed mineralizing deposits on the tested adhesive surfaces, compared to the untreated teeth discs which showed open dentinal tubules. Conclusions: The synthesized QA compound can be used as an affordable additive for imposing antibacterial properties for adhesive systems. Bioglass nanoparticles fillers impart significant remineralizing abilities to the adhesive in vitro. Keywords: Antibacterial, Streptococcus mutans, Quaternary Ammonium Compounds, Dental Adhesives, Minimum Inhibitory Concentration, Minimum Bactericidal Concentration, Time-kill kinetics, Bioglass |