In vitro assessment of experimental bioactive tooth gel formulas containing L-arginine, ginger and eggshell for remineralization and anti-bacterial effect

Abstract

Abstract The present study evaluates the effect of different novel tooth gel formulations combining L-arginine, ginger and eggshell on artificially demineralized enamel. This study used 50 bovine enamel specimens, divided into five groups according to the used toothpaste ( n  = 10): G1: Elmex Pro Argin (commercial positive control containing L-arginine), and four experimental groups; G2: ginger extract, G3: experimental eggshell + ginger, G4: experimental L-arginine + ginger, and G5: experimental L-arginine + eggshell + ginger. White-spot lesions were induced then the tested formulations were applied twice daily for one month. Evaluations at baseline, post-demineralization, and post-remineralization included Vickers microhardness (VMH), Scanning electron microscope (SEM), Energy Dispersive X-ray Analysis (EDX), elemental mapping and Confocal Laser Scanning Microscopy (CLSM). Also, antibacterial activity was assessed against commensal and cariogenic bacteria. After remineralization, all experimental groups showed a statistically significant increase in microhardness compared to their corresponding demineralized values ( P  < 0.001). Arginine-containing formulations (G4 and G5) showed statistically significant higher microhardness values and Calcium content following EDX analysis compared to the non-arginine formulations (G2 and G3) ( P  < 0.05). In agar well diffusion assay, the arginine-containing formulations (G1, G4, and G5) produced statistically significantly larger inhibition zones against both cariogenic and commensal bacterial species compared with the arginine free formulations (G2 and G3) at P  < 0.05. The synergy of L-arginine with ginger and eggshell extract provides enhanced enamel remineralization, and antimicrobial efficacy, positioning these natural tooth gel formulations as promising alternatives or adjuncts to conventional fluoride-based products.