Enhancement of Collagen and Elastic Fibers by Direct Contact Cooling-Based Monopolar Radiofrequency in a Minipig Model.

To investigate the thermal effects, dermal remodeling, and safety of a novel direct contact cooling (DCC) based monopolar radiofrequency (RF) system using a minipig model. Monopolar RF was applied at three levels. Temperature changes, visual skin assessment, hematological analysis, and histological and histochemical evaluations were performed at baseline and up to 30 day post-treatment. DCC-based monopolar RF achieved effective dermal heating without excessive epidermal temperature elevation. No adverse visual, systemic, or histological reactions were observed. Collagen density and elastic fiber remodeling were significantly enhanced at 30 days. DCC-based monopolar RF safely induces controlled dermal thermal stimulation and promotes extracellular matrix remodeling, supporting its potential as an effective non-invasive skin rejuvenation modality.