Decoding soft tissue volumizers: insights into the dynamics of gel performance and lifting capacities

In this groundbreaking study published in the International Journal of Pharmaceutics, researchers from Teoxane delved into the intricacies of soft tissue volumizers, introducing a novel perspective on their functionality. Unveiling a new dimension with the introduction of the Projection Index, this research sheds light on how these gels behave over time, uncovering their ability to maintain and lift tissues under skin tension—a facet often overlooked in conventional assessments.

Volumizing fillers, designed to create or restore facial volume, play a pivotal role in aesthetic procedures. To comprehensively assess the in vivo behavior of five commercial volumizers (Teosyal^® RHA 4, JUVVOL, RESVOL, RESLYFT, and BELVOL), our researchers employed dynamic compression to evaluate the elastic modulus (E'). Strikingly, despite similar clinical indications, each volumizer exhibited distinct behaviors. Teosyal^® RHA 4 and BELVOL demonstrated the highest resistance to strain, while Teosyal^® RHA 4, JUVVOL, and RESVOL showcased superior tissue projection capacities. Introducing a groundbreaking analytical tool, the Projection Index, the study focused on evaluating a gel's ability to lift tissues over time—a critical factor often overlooked in traditional assessments. Creep tests in compression were performed, simulating skin tension-induced stress relaxation. This innovative approach, a first in commercial fillers, provides valuable insights into the gel's resistance to dynamic compression, reflecting its capacity to withstand skin tension over time.

The study goes further to assess the gels' durability by analyzing their resistance to enzymatic degradation through a multidose approach. JUVVOL and Teosyal^® RHA 4 emerged as frontrunners, displaying the highest persistence against degradation.

“This study emphasizes the significant impact of manufacturing processes on the performance of volumizing fillers. Clear differences were observed among the gels, highlighting the need for a nuanced approach to formulation” says Jimmy Faivre, R&D Manager at Teoxane and last author of the study. “This work challenges the traditional reliance on shear elastic modulus (G') as the sole indicator of gel stiffness, introducing the elastic modulus in dynamic compression (E') as a more representative measure for clinical conditions.”

This research not only broadens the analytical tools available for characterizing soft tissue volumizers but also introduces the Projection Index as a game-changer in evaluating a gel's lifting capacities over time. By providing in vitro tools to explore gel behavior, the study aims to empower researchers in mitigating performance and safety concerns before advancing to clinical evaluations. Ultimately, these parameters aim to reduce the reliance on animal studies and enhance patient outcomes.

In the quest for developing volumizing fillers with robust mechanical properties, Teoxane study sheds light on the intricate balance required to resist skin tension, maintain tissue projection, and ensure prolonged clinical duration. As the field of aesthetic procedures continues to evolve, this research marks a significant stride toward more informed and innovative soft tissue volumizers that meet the diverse needs of patients and practitioners alike.