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. 2021 May 1;47(5):e159-e167.
doi: 10.1097/DSS.0000000000002916.

Advanced Concepts in Rheology for the Evaluation of Hyaluronic Acid-Based Soft Tissue Fillers

Jimmy Faivre  1 , Mélanie Gallet, Elodie Tremblais, Patrick Trévidic, François Bourdon
Affiliations

Advanced Concepts in Rheology for the Evaluation of Hyaluronic Acid-Based Soft Tissue Fillers

Jimmy Faivre et al. Dermatol Surg. .

Abstract

Background: Crosslinked hyaluronic acid (HA)-based soft tissue fillers possess unique viscoelastic properties intended to match specific product indications. Manufacturing has an impact on HA chain integrity and on filler properties.

Objective: This study introduces 2 new rheological parameters to evaluate the macroscopic characteristics of fillers.

Methods and materials: A library of reference commercialized HA fillers was selected to cover the full spectrum of product indications. Gels were assessed in terms of size of released HA fragments as a readout of gel integrity, degree of modification, cohesivity, and rheological properties.

Results: The elastic modulus G' often used to characterize fillers was shown not to follow macroscopic mechanical properties. To improve the mechanical characterization of fillers, Strength and Stretch scores were developed and tested. The Strength score defined the ability of a filler to sustain constant viscoelasticity over a wide range of constraints and represented the filler mechanical resilience. The Stretch score measured the propensity of a filler to deform in view to improve implant adaptation to facial animation for natural-looking results.

Conclusion: Strength and Stretch scores sorted rheological parameters to macroscopic cohesivity assays more accurately than G' and may thus help predict the gel behavior once implanted and submitted to facial dynamics.

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Conflict of interest statement

All authors are employed by Teoxane SA.

Figures

Figure 1.
Figure 1.
Characterizations of the investigated gels. Size exclusion chromatography analysis of sHA released from the gels after extraction to assess (A) the mean Mw of the released sHA fragments, (B) the percentage of released sHA per syringe, and (C) the percentage of released low Mw sHA per syringe in the distribution ranges of [0–250 kDa], [0–100 kDa], and [0–30 kDa]. (D) 1H NMR analysis of the gels to assess the MoD of the enzymatically digested gels. sHA, soluble hyaluronic acid; MoD, degree of modification.
Figure 2.
Figure 2.
Scores of (A) Strength and (B) Stretch of the gel library.
See this image and copyright information in PMC

References

    1. Sánchez-Carpintero I, Candelas D, Ruiz-Rodríguez R. Dermal fillers: types, indications, and complications. Actas Dermo-Sifiliogr (English Edition) 2010;101:381–93. - PubMed
    1. Sadick N, Sorhaindo L. The utility of soft tissue fillers in clinical dermatology: treatment of fine wrinkles and skin defects. Expert Rev Med Devices 2007;4:559–65. - PubMed
    1. Dai X, Li L, Peterson W, Baumgartner RR, et al. . Safety and effectiveness of hyaluronic acid dermal filler in correction of moderate-to-severe nasolabial folds in Chinese subjects. Clin Cosmet Invest Dermatol 2019;12:57–62. - PMC - PubMed
    1. John HE, Price RD. Perspectives in the selection of hyaluronic acid fillers for facial wrinkles and aging skin. Patient Preference Adherence 2009;3:225–30. - PMC - PubMed
    1. Beasley KL, Weiss MA, Weiss RA. Hyaluronic acid fillers: a comprehensive review. Facial Plast Surg 2009;25:86–94. - PubMed