Bioinspired Janus Universal Adhesive Patch: Bridging the Contrasting Interface of Soft Tissues and Medical Devices

Abstract Disparities in surface energy and mechanical properties present significant challenges to the integration of soft tissues with medical devices. Inspired by the natural sealing structure of the junctional epithelium in teeth, a universal dual‐layer adhesive patch that can immediately bridge contrasting interfaces between soft tissue and devices is developed. This structure comprises a semicrystalline elastomer layer with adjustable stiffness and adhesion, paired with a hydrogel layer that ensures strong tissue adhesion. Before implantation, the semicrystalline elastomer maintains a high modulus and nonadhesive properties, facilitating ease of application. Once implanted, body temperature induces melting of the crystalline region, triggering a decreased modulus and enhanced conformal adhesion to various device materials. The hydrogel layer further promotes adhesion to moist soft tissues through water absorption and chemical bonding, effectively sealing both sides of the interface. The interpenetration and cross‐linking between these two layers prevent delamination and overexpansion in humid environments, enhancing the overall performance and reliability of the adhesive patch. The universal sealing and adhesion efficacy is validated in different simulated clinical situations including denture retention, drainage tube fixation, and peri‐implantitis prevention. Therefore, the Janus adhesive patch for temporary immediate soft tissue‐device integration shows promising potential for a wide range of clinical applications.