Viscoelastic Polyurethane Discs with Host‐Guest Interaction for Temporomandibular Joint Function Restoration

Abstract The joint disc primarily functions to maintain smooth joint movement. In cases requiring replacement due to injury, it is essential to develop materials that replicate the joint's kinematic properties. To adapt to the high‐frequency motion of the temporomandibular joint (TMJ), a polyurethane incorporating host‐guest interactions is designed. Through the dynamic inclusion of cyclodextrin (CD) and adamantane (Ad), the material generates a molecular damping during deformation, exhibiting mechanical softening behavior. This imparts frequency‐dependent viscoelastic properties to the polyurethane, aligning with the high‐frequency motion characteristics of the TMJ. Moreover, the positively charged polyurethane surface enhances lubrication, closely resembling the natural TMJ disc. A shape‐performance dual‐biomimetic polyurethane disc developed from this material demonstrated remarkable efficacy in repairing rabbit TMJ disc injuries, effectively shielding condylar tissue. The polyurethane disc preserved the physiological alignment of collagen fibers and apatite distribution at the bone‐cartilage interface by optimizing strain energy. These findings confirm that the polyurethane disc, with viscoelasticity tailored to joint motion, effectively prevents abnormal structural evolution of joint tissues, retains the shock absorption function of cartilage and the mechanical support capacity of bone, and offers an innovative solution for repairing TMJ disc injuries.