Background <p>Injectable biostimulators, particularly Poly-L-Lactic Acid (PLLA), have significantly advanced aesthetic medicine by promoting collagen production for skin rejuvenation and volume restoration. This study investigates the efficacy and safety of hyperdiluted PLLA injections in the temples and neck, advocating for customized concentrations to enhance results and minimize risks. We aimed to evaluate the clinical efficacy and safety profile of hyperdiluted PLLA injections in the neck and temple region.</p> Methods <p>In this single-arm, uncontrolled exploratory study, patients were treated with injections of hyperdiluted PLLA (Rennova Elleva^®) in the neck and temple region. All patients underwent monthly clinical evaluations over six months and kept self-reporting diaries to record any adverse effects during the first 30 days. The primary outcome was patient-reported satisfaction, assessed using the Subject Global Aesthetic Improvement Scale (S-GAIS) on days 90 and 150 post-injection.</p> Results <p>On post-injection day 90, the average S-GAIS was 3.1 ± 0.86. By day 150, the mean was 2.5 ± 0.97, representing a numerical trend toward more favorable ratings that did not reach statistical significance (<i>p</i> = 0.12).</p> Conclusions <p>In this exploratory study, hyperdiluted PLLA injections in the temple and neck areas were well-tolerated, with minimal adverse effects and favorable patient-reported satisfaction trends. These preliminary findings suggest feasibility and tolerability, warranting further investigation in controlled studies with larger, more diverse populations.</p> Level of evidence <p>Level IV, therapeutic study.</p>