Bioinspired and smart material systems for auricular cartilage engineering: toward microenvironment-responsive and self-regulating scaffolds

Auricular cartilage reconstruction remains a formidable clinical challenge due to the complex anatomical structure and limited regenerative capacity of elastic cartilage. Recent advances in tissue engineering have highlighted the potential of biomimetic and smart material systems to recreate functional auricular cartilage. This review comprehensively outlines the latest progress in the design of bioinspired scaffolds that emulate extracellular matrix composition, mechanical properties and hierarchical structures. Furthermore, it discusses emerging stimulus-responsive materials capable of sensing and adapting to environmental cues-such as temperature, pH, enzymes, light, magnetism, ultrasound and mechanical stimuli-to achieve spatiotemporally controlled regeneration. While focusing on auricular cartilage, the review also draws on concepts and strategies from broader tissue engineering domains, such as bone, skin and nerve regeneration, to inform scaffold design and functional optimization. Particular attention is given to multifunctional systems integrating self-healing, nanotechnology and intelligent release platforms, as well as strategies for modulating hypoxic, immunological and biochemical microenvironments. By bridging structural biomimicry with adaptive responsiveness and self-regulation, these advanced material systems offer promising solutions for precise, durable and patient-specific auricular cartilage reconstruction. This review aims to provide a strategic framework and future directions for the development of next-generation scaffolds tailored to the complex regenerative demands of auricular tissue.