Objectives. To synthesize and characterize a novel Al+3 complex with 2-(2-hydroxyphenyl)-1H-benzimidazole (HL) to be added to a restorative glass ionomer cement (GIC) to enhance its antimicrobial activities and to evaluate the Vickers microhardness (HV) and fluoride release (FR) of the modified GIC. Materials and Methods. Al+3 complex was synthesized by the addition of 1 mmol (0.210 g) of HL to 1 mmol (0.342 g) of aluminum sulfate in ethanol. The resulting solution was then refluxed under stirring for 24 h and then collected by filtration and dried in a vacuum desiccator over an anhydrous CaCl2. Characterization of Al+3 complex was carried out by Fourier transform infrared spectroscopy (FTIR), elemental microanalysis, thermal gravimetric analysis (TGA), molar conductance, 1H NMR spectra, and electron impact-mass spectrometry. The antimicrobial activity of Al+3 complex-modified GIC (Al-GIC) was studied by the “cut plug method” against Gram-negative bacteria (Acinetobacter baumannii) and Gram-positive bacteria (Staphylococcus aureus, Enterococcus, and Streptococcus mutants) and fungi (Candida albicans). HV was evaluated by a digital microhardness tester (Zwick/Roell, Indentec, ZHVμ-S, West Midlands, England). Fluoride levels in ppm were obtained using the ion-selective electrode connected to a digital meter. A one-way ANOVA and Bonferroni test were used to analyze the data with the significance level established at p ≤ 0.05 . Results. Synthesis of Al+3 complex was confirmed by FTIR, elemental microanalysis TGA, molar conductance, 1H NMR spectra, and electron impact-mass spectrometry. Al-GICs exhibited an enhanced antibacterial activity against all studied microorganisms as confirmed by the growth of inhibition zones compared to control GIC (C-GIC). Though there was a slight reduction in HV and FR with increasing the added percent of Al+3 complex, no significant differences were found between the studied groups. Conclusions. Addition of Al+3 complex to GIC powder enhanced the antimicrobial activity of GIC materials. As there was a negligible insignificant reduction in HV and FR upon the addition of Al+3 complex, Al-GICs can be used with a guaranteed degree of clinical success.

Background: Over the last few decades, several advancements have been made in caries prevention. The use of pit and fissure sealant is one of the essential forms of prevention. Sealants protect the occlusal surfaces, inhibiting bacterial growth and providing a smooth surface. Methods: Clinical study: Forty healthy children aged 6-10 years were selected from the outpatient clinic of the Pedodontic Department, Faculty of Dentistry, Tanta University. 40 molars were sealed with "Ionoseal" & 40 molars were sealed with "Fissurit F". Laboratory study: Twenty caries-free human permanent premolars were collected and stored in 0.5% chloramines solution, then cleaned and stored in distilled water (20°C) until use. Shear bond strength was measured using a universal testing machine at cross-head speed of 1mm/min. Results: For the clinical study, there was statistically significant difference between the two groups but the quality of restorations gradually decreased from 3-months visit to 9 months visit in both groups. "Fissurit F" had better clinical performance than "Ionoseal". Both materials showed similar results with respect to caries prevention. The bond strength of "Ionseal" was statistically lower than "Fissurit F". Conclusion: The resin based fissure sealant had better clinical performance than glass ionomer cement. Both materials showed similar results with respect to caries prevention.