Evaluation of a Polydopamine-Containing Toothpaste for Antimicrobial and Anti-inflammatory Performance Against Oral Microorganisms: Antimicrobial and Anti-Inflammatory Properties of Polydopamine Toothpaste

Introduction: Polydopamine, inspired by the adhesive properties of mussel proteins, has recently drawn considerable interest in biomedical science for its antimicrobial and anti-inflammatory capabilities. In this work, a toothpaste formulation was prepared using eco-friendly synthesised polydopamine, integrated with polymethyl methacrylate (PMMA)—a biocompatible polymer valued in dentistry for its mechanical strength and resistance to degradation. PMMA was incorporated to improve the formulation’s physical stability without compromising its bioactive potential. Aim: To investigate the antimicrobial and anti-inflammatory effects of a polydopamine–PMMA toothpaste formulation. Materials and Methods: Dopamine (50 mg) was dissolved in 1 mL of distilled water at 25 °C and added to a continuously stirred mixture of 5 mL ethanol, 9 mL water, and 0.15 mL ammonium solution. Over a 24-hour reaction period, the solution gradually shifted from pale brown to deep brown, indicating successful polydopamine formation. The product was blended into a toothpaste base containing 2% w/w PMMA. Antimicrobial activity was evaluated against Streptococcus mutans, Lactobacillus spp., Staphylococcus aureus, Enterococcus faecalis, and Candida albicans. Anti-inflammatory effects were examined using bovine serum albumin (BSA) denaturation, egg albumin denaturation, and membrane stabilisation assays. Results: The polydopamine–PMMA toothpaste exhibited marked antimicrobial activity against all tested microorganisms and demonstrated notable anti-inflammatory effects across all experimental models. Conclusion: This formulation shows promise as a bioactive oral care product with both antimicrobial and anti-inflammatory benefits. However, further research—including cost-effectiveness studies, environmental impact analysis, and clinical evaluation—is required before confirming its suitability for large-scale use. Clinical Significance: Incorporating polydopamine with PMMA may yield a durable and biologically active toothpaste capable of supporting oral health by reducing microbial load and inflammation.