Facial aesthetics is a rapidly evolving field, supported by detailed anatomical knowledge, minimally invasive techniques, and a careful selection of biomaterials, particularly hyaluronic acid (HA). HA is a glycosaminoglycan naturally present in the extracellular matrix, capable of retaining up to 1000 times its weight in water, thereby ensuring hydration, elasticity, and volume (Kablik et al. 2009). Among soft tissue fillers, HA has become the gold standard for facial rejuvenation procedures and currently represents the second most frequently performed minimally invasive aesthetic treatment worldwide (International Society of Aesthetic Plastic Surgery 2024). Its widespread use is attributed to favorable characteristics such as biocompatibility, tissue integration, and reversibility through hyaluronidase (Germani et al. 2025).

Over the years, HA fillers have undergone significant technological development, evolving from simple monophasic formulations to more advanced systems, designed to improve durability, moldability, and tissue integration (Hong et al. 2024). Recently, novel fillers have been introduced with innovative particle structures that differ from conventional formulations. Preclinical evidence has demonstrated that these new fillers can stimulate extracellular matrix production and angiogenesis, while maintaining safety and biocompatibility. These advances suggest potential clinical benefits, including smoother aesthetic outcomes, improved longevity, and better adaptability to dynamic facial regions (Hahn et al. 2021).

However, despite these promising findings, such technologies have not yet been systematically evaluated in human patients. To address this gap, the present case series reports the first clinical experience with a novel cross-linked HA filler (Up, Ilikia, Brazil) applied through a full-face facial aesthetics approach.

Methods

Case series

Four patients (two female, aged 24 and 44 years, and two male, aged 30 and 41 years) presented to our private clinic seeking facial rejuvenation for different aesthetic concerns. Following individual clinical assessment, full-face treatment plans with HA fillers (Up, Ilikia, Brazil) were designed using a multilayered approach. Deep structural restoration was performed through supraperiosteal bolus injections with 27-gauge needles placed at specific anatomical points until bone contact. Subcutaneous refinements for contour and definition were carried out using retroinjection in a fan technique with 22-gauge microcannulas, ensuring smooth transitions and natural outcomes.

Results

The treatment protocols, including product type, injection sites, and total volumes used for each patient, are summarized in Table 1. Volumetric changes measured using a 3D stereophotogrammetry device (3D Life Viz™ Mini-Quantificare, Sophia Antipolis, France) are presented in Table 2.

Table 1: Description of UP treatment protocol for case 1, 2, 3 and 4.

UP –cross-linked hyaluronic acid filler (Deep, Contour, Fine).

Table 2: Volumetric changes (ml) measured using a 3D stereophotogrammetry device for case 1, 2, 3 and 4.

Case 1

A 24-year-old female patient presented with loss of lower facial definition and volume in key support areas. After treatment, she showed marked improvement in chin and mandibular projection, with natural restoration of temporal and maxillary volume and subtle lip enhancement. The overall effect was harmonious and balanced, and the patient reported high satisfaction with the outcome. No adverse events were observed during follow-up. (Figure 1).

Figure 1: Approach protocol from case 1, and stereophotogrammetry and photographic results.

Case 2

A 44-year-old female patient presented with age-related loss of mid- and lower-face support, including flattening of the zygomatic arch, mandibular contour deficiency, and deepening of the nasolabial folds. The treatment resulted in enhanced projection of the zygomatic arch, better mandibular definition, and softening of the nasolabial folds, producing a rejuvenated and more feminine appearance. The patient expressed satisfaction with the results, and no adverse events were reported. (Figure 2).

Figure 2: Approach protocol from case 2, and stereophotogrammetry and photographic results.

Case 3

A 30-year-old male patient sought treatment to improve mandibular contour and correct unilateral temporal hollowing. The procedure achieved a well-defined mandibular line and symmetric temporal volume restoration, providing a more balanced and youthful facial appearance. The patient reported high satisfaction, and no adverse effects were observed during follow-up. (Figure 3).

Figure 3: Approach protocol from case 3, and stereophotogrammetry and photographic results.

Case 4

A 41-year-old male patient presented with concerns of prominent tear troughs and reduced mandibular definition. Following treatment, there was a visible improvement in the infraorbital region, with attenuation of the tear troughs, along with a more defined mandibular contour and improved maxillary support. The results contributed to a refreshed and rejuvenated look, with high patient satisfaction. No complications or adverse events were noted during follow-up. (Figure 4).

Figure 4: Approach protocol from case 4, and stereophotogrammetry and photographic results.