Preliminary morphological characterization of injectable gels for aesthetic medicine applications

María Recuero Pradillo; Paloma Tejero-García; Sheila Karina Mota Antigua; Marta Ortega Zamorano; Santiago Coca Menchero; Manuel Flores Sáenz

doi:10.57662/am.v11i4.18197

Preliminary morphological characterization of injectable gels for aesthetic medicine applications

Authors

María Recuero Pradillo Specialist Physician in Pathological Anatomy, Spain
Paloma Tejero-García University of Alcalá, Madrid, Spain; TClinic – Institute of Medicine and Wellness, Toledo, Spain
Sheila Karina Mota Antigua MBL Training Department, Wellness and Longevity Medicine Training (MBL), Madrid, Spain https://orcid.org/0009-0009-1910-8699
Marta Ortega Zamorano TClinic – Institute of Medicine and Wellness, Toledo, Spain https://orcid.org/0009-0002-3687-1011
Santiago Coca Menchero Department of Medicine and Medical Specialties, University of Alcalá, Madrid, Spain
Manuel Flores Sáenz University of Alcalá, Department of Surgery, Medical and Social Sciences, Teaching Unit of Human Anatomy and Embryology, Laboratory of Osseointegration and Microscopic Anatomy, Science and Technology Campus, Madrid, Spain https://orcid.org/0009-0001-1049-5102

Keywords:

Injectable gels, filler materials, morphological characterization, optical microscopy, biostimulating agents

Abstract

Background: Injectable gels used in aesthetic medicine for skin rejuvenation are known collectively as fillers. These gels are employed for wrinkle correction, volume restoration, and facial enhancement with some formulations predominantly providing bio-stimulating and revitalizing effects.

Aim: This study aimed to analyze and compare the microscopic structure of various injectable gels.

Materials and Methods: Ten products were examined, including cross-linked and non-cross-linked hyaluronic acid (HA), agarose gel, calcium hydroxyapatite combined with HA, and formulations containing collagen precursors. Smears were prepared on glass slides, air-dried, stained with Diff-Quick, and observed under optical microscopy.

Results: Each material exhibited a distinct and reproducible microscopic morphology corresponding to its composition.

Discussion: Microscopic analysis of injectable gels can help identify and categorize products based on their structural characteristics. This tool may assist in the identification of undocumented materials in cases of adverse reactions through fine-needle aspiration (FNA) and smear analysis.

Conclusions: Morphological analysis may serve as a valuable framework to understanding the potential behavior and integration of gels within biological tissues. Greater attention to microscopic studies of injectable gels may enhance safety, efficacy, and complication management in aesthetic procedures.

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