Effect of Different Crosslinking Technologies on Hyaluronic Acid Behavior: A Visual and Microscopic Study of Seven Hyaluronic Acid Gels.

BACKGROUND The mechanical, rheological, and pharmacological properties of hyaluronic acid (HA) gels differ by their proprietary crosslinking technologies. OBJECTIVE To examine the different properties of a range of HA gels using simple and easily reproducible laboratory tests to better understand their suitability for particular indications. METHODS AND MATERIALS Hyaluronic acid gels produced by one of 7 different crosslinking technologies were subjected to tests for cohesivity, resistance to stretch, and microscopic examination. These 7 gels were: non-animal stabilized HA (NASHA® [Restylane®]), 3D Matrix (Surgiderm® 24 XP), cohesive polydensified matrix (CPM® [Belotero® Balance]), interpenetrating network-like (IPN-like [Stylage® M]), Vycross® (Juvéderm Volbella®), optimal balance technology (OBT® [Emervel Classic]), and resilient HA (RHA® [Teosyal Global Action]). RESULTS Cohesivity varied for the 7 gels, with NASHA being the least cohesive and CPM the most cohesive. The remaining gels could be described as partially cohesive. The resistance to stretch test confirmed the cohesivity findings, with CPM having the greatest resistance. Light microscopy of the 7 gels revealed HA particles of varying size and distribution. CPM was the only gel to have no particles visible at a microscopic level. CONCLUSION Hyaluronic acid gels are produced with a range of different crosslinking technologies. Simple laboratory tests show how these can influence a gel's behavior, and can help physicians select the optimal product for a specific treatment indication. Versions of this paper have been previously published in French and in Dutch in the Belgian journal Dermatologie Actualité. Micheels P, Sarazin D, Tran C, Salomon D. Un gel d'acide hyaluronique est-il semblable à son concurrent? Derm-Actu. 2015;14:38-43. J Drugs Dermatol. 2016;15(5):600-606..