Periapical Tissue Response to Allicin-rGO-AgNP Hydrogel Intended as an Intracanal Medicament: A Rat Model Study

a large surface area for interaction with microbial membranes and the ability to generate reactive oxygen species, thus exhibiting IntroductIonThe investigation of periapical tissue response to novel therapeutic agents is critical for advancing endodontic treatment strategies. 1 In cases involving persistent periapical inflammation or necrotic pulps, the placement of intracanal medicaments becomes indispensable to ensure continued disinfection, modulation of the inflammatory response, and promotion of tissue healing between appointments or prior to final obturation. [2][3]][4] An ideal intracanal medicament should possess potent antimicrobial properties, be biocompatible with the host tissues, and facilitate periapical healing without inducing cytotoxic effects or persistent inflammation. 5Calcium hydroxide is widely regarded as the gold standard among intracanal medicaments, owing to its broad antimicrobial spectrum and its capacity to stimulate hard tissue formation by releasing hydroxyl ions. 6,7However, its efficacy may be limited by its high pH-induced cytotoxicity and poor performance against certain resistant bacterial species. 8ntibiotic-based pastes, such as the double antibiotic paste (DAP), often composed of metronidazole and ciprofloxacin, have demonstrated high antibacterial efficacy in regenerative endodontic procedures. 9However, concerns regarding their cytotoxicity, potential to alter stem cell viability, and risks of antibiotic resistance have prompted researchers to explore novel alternatives.In recent years, advances in nanotechnology have led to the development of composite biomaterials with enhanced biological and antibacterial profiles. 10Reduced graphene oxide-silver nanoparticles (rGO-AgNPs) represent one such innovation, offering 1,