An antioxidant and antibacterial octyl gallate sustained-release ointment for periodontitis treatment

Periodontitis is a chronic inflammatory disease that leads to periodontal attachment loss and is a major cause of adult tooth loss. Current treatment of mechanical debridement is often ineffective in deep periodontal pockets, and antibiotic adjuncts carry the risk of bacterial resistance. Octyl gallate (OG), a natural plant-derived compound with antibacterial and antioxidant properties, is limited by poor water solubility and stability. This study aimed to develop a sustained-release ointment (OG-Ointment) using Pluronic F127 and ethylcellulose to enhance the delivery and efficacy of OG. The formulated OG-Ointment demonstrated excellent rheological properties, sustained drug release, and potent ABTS⁺ radical scavenging. In vitro, it enhanced bacterial membrane permeability, inhibited P. gingivalis growth, and reduced ROS in macrophages. In a rat periodontitis model, OG-Ointment significantly reduced alveolar bone resorption, decreased ROS and inflammatory cytokines, and exhibited good biocompatibility. These findings suggest that OG-Ointment is a promising non-antibiotic adjunctive therapy for periodontitis, combining dual antioxidant and antibacterial functions with sustained release.