Mono threads are smooth, absorbable threads made of polydioxanone (PDO) used in non-surgical aesthetic treatments to tighten and rejuvenate the skin. Unlike barbed threads, mono threads do not lift but instead stimulate collagen production when inserted into the skin, improving elasticity, texture, and reducing fine lines. Commonly used on the face and neck, they are ideal for patients seeking subtle, natural-looking skin rejuvenation with minimal downtime. Results gradually appear over a few months and can last up to a year.