Evolution of Thread Lifting: Advancing Toward Bioactive Polymers and Sustained Hyaluronic Acid Delivery

Abstract

Facial aging is a multifactorial and stratified biological process characterized by progressive morphological and biochemical alterations affecting both cutaneous (Layer I) and subcutaneous (Layer II) tissues. These age-related changes manifest clinically as volume depletion, tissue ptosis, and a decline in overall skin quality. In response to these phenomena, thread lifting techniques have evolved significantly—from simple mechanical suspension methods to sophisticated bioactive platforms. Contemporary threads now incorporate biocompatible polymers and hyaluronic acid (HA), aiming not only to reposition soft tissues but also to promote dermal regeneration. This review provides a comprehensive classification and critical assessment of thread lifting materials, focusing on their chemical composition, mechanical performance, degradation kinetics, and biostimulatory potential. Particular emphasis has been given to the surface integration of HA into monofilament threads, especially with the emergence of advanced delivery systems such as NAMICA, which facilitate sustained HA release. Advanced thread materials, especially those fabricated from poly(L-lactide-co-ε-caprolactone) [P(LA/CL)], demonstrate both tensile support and regenerative efficacy. Emerging HA-covered threads exhibit synergistic bioactivity, stimulating skin remodeling. NAMICA technology represents an advancement in the field, in which HA is encapsulated within biodegradable polymer fibers to enable gradual release and enhanced dermal integration. Nonetheless, well-designed human studies are still needed to substantiate its therapeutic efficacy. Consequently, the paradigm of thread lifting is shifting from purely mechanical interventions toward biologically active systems that promote comprehensive ECM regeneration. The integration of HA into resorbable threads, especially when combined with sustained-release technologies, represents a meaningful innovation in aesthetic dermatology, meriting further preclinical and clinical evaluation.