Periodontitis is driven by a self-reinforcing cycle of persistent inflammation and cellular senescence, further exacerbated by pathogenic microbial colonization. To address this challenge, inspired by the “fortress effect”, we report an allicin-based nanoplatform of biolubrication (PPCG) that establishes a physical and biological protective barrier for precise modulation of the periodontal microenvironment. PPCG integrates hydration-lubricating diblock copolymer P(DMA-bMPC) (PDMPC) with bioactive allicin. The lubricating PDMPC barrier may suppress pathogenic microbial adhesion and biofilm formation, constituting an “outer fortress wall” against bacterial invasion. Concurrently, sustained release of allicin could regulate bone marrow mesenchymal stem cells (BMMSCs) and mitigate inflammatory responses. It could preserve stemness and multipotent differentiation potential, thereby forming an “inner defensive citadel” that promotes soft and hard tissue regeneration. This dual protective barrier can markedly attenuate periodontal tissue senescence and inflammatory and prevent alveolar bone loss in mice periodontitis model. Furthermore, PPCG could rebalance the oral microbiota and maintain ecological homeostasis. Therapeutic efficacy is also corroborated using an artificial intelligence-assisted detection system based on the YOLO v8 deep learning model. Collectively, this study presents a therapeutic intervention strategy for periodontitis, offering a scalable and translational approach for treating inflammation and senescence.