The Microcannula Technique: How to Use a Blunt Tip Cannula for Filler

If you place dermal filler, you have probably weighed blunt tip cannulas (18G to 30G) against a needle for some of your treatments. This guide, written for licensed practitioners, explains how the microcannula technique works and how to choose a gauge and length.

You will leave with the vocabulary to compare your options, a short list of what belongs on a cannula tray, and a map of the training that teaches the hands-on side.

What Is the Microcannula Technique?

A microcannula is a blunt-tipped, flexible instrument that places dermal filler through one small entry point instead of repeated needle punctures.

This guide is general information for licensed practitioners using their own clinical judgment. It is not a treatment protocol. Depth, plane, entry site, angle and injection pattern are your decisions and are taught in hands-on and online training, so you will not find them prescribed here.

Next, you will read about choosing between a blunt tip cannula and a needle, the general sequence, gauge and length, the cannula tray, and where to learn the technique.

Blunt Tip Cannula vs Needle: Choosing the Tool

A blunt tip cannula and a needle differ in tip design and in how many times the skin is entered, and the choice between them is a clinical decision that depends on the area and the filler.

A needle has a sharp point, and each placement is its own puncture. A blunt tip cannula is built the other way around. Our product specifications list the tip as blunt and flexible, and several sizes also list it as atraumatic. The blunt tip is designed to glide past tissue rather than cut through it, and one entry point serves the whole pass instead of a series of punctures.

Which tool fits a given area and filler is your call. The AFI 1.2 and AFI 1.3 courses cover cannula versus needle selection, and both are linked in the training section below.

How the Microcannula Technique Works

In the microcannula technique, you open an entry point with a separate sharp needle, pass the cannula through it, and place filler along the path.

That separate needle is called a pilot needle, or entry needle. It opens the entry point, and the cannula then goes through it. Length matters here because a longer shaft lets one entry point reach a longer corridor of tissue. The 70 mm length, for example, is described on its product page as reaching a long corridor of tissue from one entry point.

The shaft is flexible, and a flexible shaft resists bending, so the cannula holds its line and keeps the filler flowing smoothly.

Everything beyond that general sequence is clinical judgment. Where you enter, how deep you work, which plane you target and what pattern you use are taught in hands-on and online training. This guide gives no angles, depths, volumes or step-by-step protocols.

Choosing a Cannula Gauge and Length

Gauge sets the bore, which follows the viscosity of your filler, and length sets the reach, which follows the treatment zone.

Our range of blunt tip cannulas (18G to 30G) covers eight gauges (18G, 21G, 22G, 23G, 24G, 25G, 27G and 30G) in five lengths (25, 38, 50, 70 and 100 mm). The size table on our dermal filler cannula page lists every gauge and length, so this guide does not repeat it.

Gauge and filler viscosity

Product listings pair bore with filler type this way:

• 18G and 21G: wide bores that handle higher-viscosity and structural fillers.
• 22G and 23G: mid bores that handle mid-viscosity hyaluronic acid fillers.
• 25G and 27G: fine and ultra-fine bores that handle thin, low-viscosity hyaluronic acid fillers.
• 30G: a bore that suits less viscous hyaluronic acid fillers.

The 25G listing adds that a finer cannula gives more tactile feedback in delicate tissue.

Length and treatment zone

• 25 mm: suits precise work such as tear trough and peri-oral filling.
• 38 mm: suits contained zones where you want reach but tighter control.
• 50 mm: covers broader areas from one puncture.
• 70 mm: lets one entry point reach a long corridor of tissue.

Three sizes and their listed uses

• 25 gauge cannula, 38 mm: listed for lips, fine lines and compact facial zones.
• 27G 38 mm blunt tip cannula: listed for tear trough, lips and the most delicate planes.
• 22G 50 mm cannula: listed for routine cheek, mid-face and jawline filler.

Whether a size suits your patient and your filler is your judgment.

Setting Up a Cannula Tray

A cannula tray needs the cannula and a separate pilot needle, because a single-size box does not include one.

A single-size box holds 20 cannulas and nothing else. The 30G 25 mm box holds 50. Plan your pilot needles separately.

Each cannula is sterile and individually packed. Use one per patient and dispose of it in a sharps container.

Several sizes have a Luer-lock hub, though not all of them. Check the listing for the size you plan to use before you match it to a syringe.

If you are new to cannula technique, or your practice is adding cannula-based filler work, the Microcannula Professional Starter Kit is built for that. Check the kit's product page for what it contains.

Learning Cannula Technique

The details this guide leaves out, such as depth, plane and pattern, are taught in training.

The Size Progression Training Kit is set up for learning. A trainee starts on more forgiving sizes, then steps up to gauges and lengths that demand more control.

Our online injector training courses include three AFI courses relevant to this topic:

• AFI 1.2 Intermediate Dermal Filler teaches facial-plane identification and cannula-versus-needle selection, with the chin, jaw, sub-zygomatic region and marionette lines.
• AFI 1.3 Advanced Dermal Filler covers which filler injections respond best to a needle and which to a blunt-tip cannula, with demonstrations in the nasolabial folds, tear trough and periorbital area.
• AFI 1.0 Complications & Vascular Emergencies covers complications. Its listing puts it plainly: "Filler is a non-invasive procedure, but non-invasive is not the same as risk-free."

Key Takeaways

• A microcannula places filler through one small entry point with a blunt, flexible tip instead of repeated needle punctures.
• The entry point is opened with a separate sharp pilot (entry) needle. Single-size boxes do not include one.
• Bore follows filler viscosity, and length follows the treatment zone.
• Each cannula is sterile and single-use, and several sizes have a Luer-lock hub.
• Tool choice, depth and pattern are clinical decisions taught in training.

Related Guides and Supplies

Explore the full microcannula range, the online training course category, and syringes and needles.

When you are ready to compare sizes, the cannula range lists every gauge and length in one place. Pair it with training that matches the way you work.