Medically reviewed by Dr Sin Yong · Last reviewed · 3 min read
Published 13 October 2026 · Reviewed by Dr Sin Yong
Poly-L-lactic acid (PLLA) is a biodegradable synthetic polymer injected as a dilute suspension of microparticles so that the skin builds collagen around them over weeks and months. PLLA is the material in Sculptra. It adds little volume on the day and is a collagen biostimulator rather than a filler; fibroblasts lay down new type I collagen while the PLLA itself degrades by hydrolysis. Once placed it cannot be dissolved.
Key facts
Material
Biodegradable synthetic polymer, supplied as a sterile powder of microparticles reconstituted before injection
Product
Sculptra (Galderma)
Mechanism
Fibroblasts respond to the microparticles by laying down type I collagen; the PLLA degrades by hydrolysis
Dissolvable?
No. Hyaluronidase acts on hyaluronic acid only and does nothing to PLLA
Where it fits
PLLA is the oldest of the three collagen biostimulators Dr Sin Yong uses, and the one whose change is slowest and most gradual. On the Sculptra page he reserves it for broad, diffuse volume loss in the temples and mid-face in faces with good skin thickness, and not for the lips, tear troughs or anywhere a nodule would be visible. The same material appears in a different stereochemistry as poly-D,L-lactic acid. Because PLLA cannot be dissolved, over-stimulation is managed differently from hyaluronic acid: Dr Sin Yong's Time Freeze Laser LCLR® is built to target areas over-stimulated by Sculptra or Ellansé and take away the excess, after ultrasound mapping. The class as a whole is defined under biostimulator in this glossary.
Frequently Asked Questions
Not in the usual sense. A filler gives volume on the day from the material itself; PLLA adds little volume at injection and the change builds as the skin lays down collagen around the particles over months.
No. Hyaluronidase has no action on PLLA. Over-correction has otherwise relied on time, steroid injection and excision; Dr Sin Yong's Time Freeze Laser LCLR® is built to target over-stimulated tissue and take away the excess.
References
Lee KWA, et al. Poly-d,l-lactic acid (PDLLA) application in dermatology: a literature review. Polymers. 2024;16(18):2583. doi:10.3390/polym16182583. source
