The Foaming Technique: Innovation in Mixing Calcium Hydroxylapatite Applied in Hybrid Filler.

Abstract

Background: Hyaluronic acid (HA) and calcium hydroxylapatite (CaHA) are commonly used in nonsurgical aesthetic procedures. This study introduces a novel mixing technique, the foaming technique, aimed at enhancing the homogeneity and distribution of hybrid fillers containing CaHA and HA.

Methods: This retrospective study, conducted by five expert injectors between January 2022 and January 2024, evaluates the clinical outcomes and microscopic characteristics of the foaming technique. The technique involves premixing CaHA, HA, and lidocaine and subjecting the mixture to repeated negative pressure suctions to create foam, followed by additional mixing passes.

Results: The study, conducted between January 2022 and January 2024, treated 1559 patients with hybrid fillers using the foaming technique and revealed no adverse events. Electron microscopy analysis highlighted distinct characteristics of the filler samples (1-CaHA; 2-CaHA, CPM-HA, and lidocaine without foaming; and 3-CaHA, CPM-HA, and lidocaine with foaming), showing a more homogeneous mixture when the foaming technique was applied. Sonography further elucidated unique imaging patterns influenced by the presence of foam, indicative of well-defined borders and the presence of a ring-down artifact. Conversely, in the absence of foam, the imaging typically revealed a band-like product with a less defined border.

Conclusion: The foaming technique demonstrates improved homogeneity and distribution of the premixed hybrid filler, along with the absence of adverse events and smoother particle surfaces observed in electron microscopy samples. Sonography further corroborated these findings, revealing a more uniform pattern with the foam, thereby influencing imaging characteristics. This technique signifies a significant advancement in optimizing hybrid filler applications.

Level of evidence iv: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .