At first when dermal fillers began to become more popular, they were administered under the skin using a hypodermic needle. However, cannulas have become more popular in recent years, particularly for certain areas of the face and body. In fact, many of the dermal fillers that we can find today come both with a needle and cannula so that the practitioner who is going to apply the product himself decides how to inject the filler.
Differences between cannulas and needles
Cannulas and needles differ in the type of tip, although many times both options are used at the same time. They have advantages and inconvenients, so many professionals just use both of them at the same time depending on the zone of application, the depth and the precision needed.
Advantages of using hypodermic needles
The most plausible and obvious difference between a needle and a cannula is that the needle tip is sharp while the cannula tip is not. Therefore, in the case of a hypodermic needle, there is more risk of small bruises from broken capillaries or blood vessels when inserted under the skin. While any professional who specializes in dermal fillers also has a great deal of knowledge about the anatomy of the face and any other part of the body where the filler is to be applied (and therefore knows the exact location of the major blood vessels), there are very subtle anatomical differences from person to person, which means that there is rarely any 100% guarantee that a small bruise will not appear after the application of a dermal filler. These bruises usually disappear the next day or within a few days, as they are tiny blood vessels that are quickly repaired by our body. However, the great advantage of a hypodermic needle is its great precision when applying the filler in specific areas (for example in the case of the lips), both in location and in depth.
Advantages of using cannulas
On the other hand, a cannula does not have a sharp tip, so it is much easier for it to move under the skin through the blood vessels without breaking them, which means it will be less likely to cause a bruise. Also unlike hypodermic needles, a cannula is usually longer and more flexible than a needle. This length and flexibility allows the cannula to deliver the dermal filler more smoothly and continuously along the entire line of application, for example following the line of the wrinkle that is intended to be dissimulated. A cannula also allows for fewer injections, as it can reach a little further into the skin but will not be suitable when extreme precision is needed.
When to use one or the other
Most professionals combine a needle and a cannula depending on the area of application, depth and precision required. On the image on the left you can see a full face treatment using a cannula. To learn more about it read one of our blog posts.