Strengthening the Key Features of Volumizing Fillers: Projection Capacity and Long-Term Persistence

• Main Authors: Killian Flégeau (Author), Jing Jing (Author), Camille Vantou (Author), Romain Brusini (Author), François Bourdon (Author), Jimmy Faivre (Author)
• Format: Book
• Published: MDPI AG, 2023-11-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Volumizing fillers aim to create or restore facial volume in fat layers. To provide strong tissue lifting and long-term persistence, gels are generally designed with stiff properties, characterized by a high storage modulus (G'). However, clinical evidence shows a discrepancy between high G' and good lifting capacities, especially after skin tension has been exerted on the gel. To better explore the in vivo behavior of a gel, we first evaluated the elastic moduli of five commercial volumizers (RHA₄, JUV_VOL, RES_VOL, RES_LYFT, and BEL_VOL) in dynamic compression mode, E'. We further developed a Projection Index score based on the rheological assessment of creep in compression to mimic skin tension-induced stress relaxation (flattening). Finally, the ability of a gel to resist enzymatic degradation was analyzed with a multidose approach. Despite similar clinical indications, volumizers exhibited distinct behaviors. RHA₄ and BEL_VOL showed the highest E' values (resistance to strain), RHA₄, JUV_VOL, and RES_VOL exhibited the greatest projection capacities, while JUV_VOL and RHA₄ offered the largest persistence to enzymatic degradation. In this article, we introduce the use of the Projection Index to efficiently assess the ability of a gel to lift tissues, thus increasing preclinical models' efficiency and reducing the need for animal studies.

Item Description

10.3390/pharmaceutics15112585
1999-4923