Dermal filler:
what the term means

What a dermal filler is, and how it works

A dermal filler is a gel injected with a needle or cannula into a specific plane, from just beneath the skin to directly on bone, where it occupies space and supports the tissue above it. Hyaluronic acid fillers are cross-linked gels of a molecule found naturally in skin; they give volume at injection, hold water, are gradually broken down by the body and can be dissolved with hyaluronidase if they need to be. Softer gels suit lips and fine lines; firmer gels support the cheek, chin and jawline.

The other classes work partly or wholly by stimulating collagen. Radiesse is calcium hydroxylapatite microspheres in a gel carrier: the gel gives volume and, as it clears, the microspheres remain as a scaffold for new collagen. Ellansé is polycaprolactone microspheres on the same principle, and Sculptra is poly-L-lactic acid, which gives no volume on the day and works through the collagen response over months. None of these three is reversed by hyaluronidase.

How dermal fillers are used in aesthetic medicine

Fillers are used where volume has genuinely been lost: the cheeks and midface as fat compartments deflate and bone resorbs, the temples, the chin and jawline, the tear trough, the lips and the backs of the hands. The product follows the area. Dr Sin Yong prefers Radiesse and Ellansé for deep structural volume in the cheek and midface, and hyaluronic acid for the lips, tear troughs and superficial placements, where reversibility matters most. How this is planned is explained on the volume restoration page.

The amount is conservative and added in steps, placed in the correct fat compartment rather than spread beneath the skin where it can migrate. Where descent is present, lifting the tissue first with an energy-based protocol reduces the deficit that filler then has to cover. A fuller guide to the types, risks and the problem of over-filling sits in the dermal fillers guide.

“Volume loss is the ageing nobody names — the folds get blamed while the hollows get missed.”

Dr Sin YongOn facial volume loss

What dermal filler is often confused with

Filler and botulinum toxin are regularly conflated. Botulinum toxin relaxes a muscle and softens lines made by movement; filler replaces volume and supports lines present at rest. Neither does the other's job. Skin boosters are also hyaluronic acid, but in a lightly or non-cross-linked form placed in fine droplets to hydrate the dermis, not to change contour; a booster will not lift a cheek, and a filler is the wrong tool for dull, dehydrated skin.

Collagen biostimulators are often marketed simply as fillers, and the distinction matters when something needs correcting: hyaluronidase dissolves hyaluronic acid and nothing else, so a lump or excess after Sculptra, Ellansé or Radiesse is assessed and managed case by case rather than dissolved. Fat grafting is a surgical alternative using the patient's own fat, referred to a plastic surgery specialist, and it is not reversible either.

When dermal filler is not the answer

Filler added to tissue that has descended rather than deflated makes a face heavier, not younger, and the overfilled pillow face usually arrives one reasonable appointment at a time. Where the complaint is sagging, laxity or jowling, lifting comes first and filler, if needed at all, is reserved for the deficit that remains. Where the face already feels heavy or puffy, the honest options are dissolving, managing or waiting, which is the work of filler correction.

Filler injection also carries a small but serious risk, vascular occlusion, in which product enters or compresses an artery. Skin that turns white, dusky or mottled, pain that worsens rather than settles, or any change in vision after filler needs same-day medical assessment, and vision change is an emergency. That risk is one reason product choice follows the area, hyaluronidase is kept to hand wherever hyaluronic acid is injected, and the nose and tear trough are approached conservatively.