BACKGROUND: Poly-L-lactic acid (PLLA) is widely used in aesthetic medicine due to its bio-stimulatory properties. However, limited research has compared different PLLA formulations. AIM: To evaluate the impact of PLLA formulation and injection depth (subcutaneous vs. supraperiosteal) using objective and subjective assessments. MATERIALS AND METHODS: This randomized clinical trial with split-face and parallel components included 20 participants. Each participant received a single PLLA formulation of PLLA-SCA (Sculptra) or PLLA-ELL (Elleva), while the injection plane was alternated between hemifaces. Dermal thickness was assessed using ultrasonography at baseline, 60, and 120 days. Patient satisfaction was evaluated using the Global Aesthetic Improvement Scale (GAIS). RESULTS: Dermal thickness increased over time but showed no significant differences between products (p = 0.78) or injection planes (p = 0.83). GAIS scores were positive at 60 days but declined significantly at 120 days (p = 0.031), particularly for PLLA-ELL (p = 0.022). No significant correlation was found between dermal thickness and GAIS scores at 60 (ρ = -0.038, p = 0.819) or 120 days (ρ = 0.016, p = 0.927). CONCLUSIONS: Injection depth did not significantly influence PLLA outcomes. However, differences in patient satisfaction between PLLA formulations highlight the role of physicochemical properties in treatment longevity. These findings emphasized the need to integrate objective and subjective measures in assessing bio-stimulatory treatments.
Munoz-Lora et al. (Fri,) studied this question.