At Dr Aesthetica, we have a lifelong commitment to offering exemplary services and educating our patients on the most up-to-date technologies, procedures, and products available in the field of minimally invasive facial aesthetic medicine.
Today we will look at the two most popular methods of injecting dermal fillers into the skin: needles vs microcannulas. We will also highlight the pros & cons of each, and at the end, we will share our most preferred method.
What is a Dermal Filler Microcannula?
Successful soft-tissue filler treatment is predicated on several factors: selecting the appropriate injectable product, placement precision and artistic flair. Having said that, every practitioner's primary concern is safety—hence the rising popularity of microcannulas over the past few years.
The word "cannula" comes from Latin, meaning "little reed." Essentially, a cannula is a flexible tube inserted into a bodily cavity, duct, or vessel to administer or remove fluid.
Cannulas have been used for various applications in medicine for more than a hundred years, most frequently for intravenous therapy.
In the context of dermal fillers, a microcannula is a blunt-tipped, hollow tube that functions as an alternative to a hypodermic needle when administering dermal fillers.
When using the cannula injection technique, the doctor uses a small introducer needle to create an entry point for the cannula (which is blunt and unable to pierce through the skin). The cannula is then inserted into the puncture site, gaining access to the deeper layers of the skin.
Since most cannulas used for filler treatments have a flexible shaft and are at least 1 inch long, the dermal filler can be administered along the natural planes of skin tissue from a single entry point.
Benefits of the Cannula Method
The needle technique relies on the bevelled edge of a hypodermic needle tip to penetrate the surface of the skin and the subdermal layers below.
This means less effort is needed to administer the filler. On the flip side, the sharp needle can easily pass into or through a blood vessel, posing a higher risk of complications such as the rare vascular occlusion.
Due to a cannula needle being blunt, it's much less likely to pierce a blood vessel or cause damage to the deep tissue within the skin.
The injector can easily detect resistance from the tissue structures that the cannula passes through. This allows them to judge when to apply/release pressure or alter the direction of the cannula to avoid veins, arteries and nerves.
Fewer entry points mean less pain or discomfort for the patient. Many people describe needle injections as painful, while patients treated with the cannula method describe the sensation as "pressure." There is also a decreased risk of bleeding, bruising and swelling, which are common side effects of dermal filler treatments.
The cannula allows the injector to place multidirectional, even layers of filler rather than multiple localised blobs from needle injections. Because the filler can be distributed smoothly and uninterrupted along the tissue plane, less massaging and manipulation of filler is needed.
The outcome is a more flawless, natural-looking result.
Risks Posed by the Cannula Technique
It Doesn't Completely Eliminate the Risk of Severe Complications.
Cannulas still have the potential to cause neurovascular injury or even penetrate a blood vessel if passed through skin tissue with inappropriate force. This usually occurs because of overcompensation for the smooth penetrating action of a sharp tip needle.
This is particularly crucial when targeting areas like the nasolabial fold that require deep dermal filler injection.
There are 3 things to consider in terms of cannula safety: size & shape of cannula and direction of injection. All these are greatly dependent on having a thorough understanding of facial anatomy. Again this comes down to the skill of the injector.
It's a Fairly New Technique
Technically, the cannula technique requires more experience and skill than the needle method, which is why this technique is yet to become as prevalent as the latter.
For example, injectors have to account for the G Prime of the facial filler product. This refers to the general density or thickness of a filler and greatly influences the flow and distribution of the filler under the patient's skin.
Having been around for only a few years, it's also a relatively new injection option.
Currently, there are only 4 FDA approved uses for cannula:
- Restylane Silk – Lips – 2017
- Restylane Lyft – Cheeks – 2018
- Juvederm Voluma – Cheeks – 2019
- Juvederm Voluma – Chin/Prejowel sulcus – 2020
That said, dermatologists, plastic surgeons and aesthetics doctors have found safe applications for cannulas for non-surgical cosmetic treatments beyond these four.
Nevertheless, optimal placement and results ultimately depend upon the knowledge and skill of the injector.
This means the pool of practitioners who can safely use cannulas is smaller than those who specialise only in the traditional needle technique.
As we often point out, you need to do your due diligence when selecting a doctor for your filler or botox treatment.
When to Use a Needle Instead
While the cannula method for injecting dermal fillers offers many benefits, there are many instances when needles are more desirable for product delivery than a microcannula.
A small needle often allows for more control and accuracy, especially in areas that require a great deal of precision. An example of this is treating the fine "smoker's lines" around the lips, where a light hand is needed to deliver tiny amounts of filler quite superficially.
In this instance, a cannula simply wouldn't allow for the same level of control.
A Personalised Approach
There is no one-size-fits-all when it comes to achieving the best results. Some practitioners feel highly confident carrying out most of their dermal filler procedures using just a needle or a cannula.
In contrast, others are happy to switch between the two depending on the individual case. We prefer the last option.
Both methods provide excellent results when used correctly, and each one has its place in safely and effectively delivering dermal fillers.
In fact, many dermal filler products are now packaged with both a needle and a cannula to allow the practitioner more choice when deciding how to inject the product.
The exact method we settle on is determined by your primary concerns, aesthetic goals (what do you want to accomplish from your treatment), and the areas of the face we will be targeting.
Book your dermal filler appointment online and meet with one of our trusted professionals to go over your options.