Rheological Properties of Hyaluronic Acid Fillers for Lip Volumization.

INTRODUCTION

Hyaluronic acid (HA) is widely used for facial rejuvenation and soft tissue volumization, with lip augmentation being one of its primary applications. The rheological properties of HA fillers are essential to ensure the efficacy and safety of procedures, directly influencing the aesthetic outcome and material longevity.

OBJECTIVE

This study aims to evaluate the rheological properties of three hyaluronic acid-based fillers indicated for lip volumization: Belotero Intense (Merz), Kysse (Galderma), and Volift (Allergan).

METHODS

Twenty-four syringes of fillers were analyzed, with 8 samples from each brand. The rheological properties investigated included storage modulus (G'), loss modulus (G''), complex modulus (G*), phase angle (Tan(delta)), and cohesiveness. Measurements were conducted using the Kinexus PRO rheometer with parallel plate geometry.

RESULTS

The results revealed significant differences among the three fillers. Volift exhibited higher resistance to deformation, reflected by the higher G* values, while Kysse stood out for its greater cohesiveness.

CONCLUSION

These rheological variations suggest that each filler may be more suitable for different clinical applications, such as lip augmentation or deeper tissue filling.

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