Needle vs. Cannula
Both options, needle and cannula, are widely used in aesthetics by practitioners, but have you ever wondered what the difference is?
Traditionally, dermal fillers have been injected using a sharp needle. Indeed, most dermal fillers are packaged with two short needles as the suppliers recommend injecting their product for treatment. So what would be the advantage of completing treatment with a dermal blunt-tipped cannula? And why is one chosen over the other for specific treatments?
Cannulas
Cannulas are long, flexible tubes that are blunt at the tip with a hollow bore. Due to being blunt-ended, a sharp needle must make an entry point into the skin to allow passage of the cannula into the tissues. Therefore, a single entry point is created with a sharp needle, and the cannula is introduced and threaded through the tissue.
Cannulas let the injector treat larger surface areas at a time via one injection site, allowing them to contour areas like the cheeks and jawline. The cannula can re-enter this same entry point multiple times without needing another puncture for the patient. Because of this, a blunt-ended cannula can treat several areas from this one entry point by changing the angle the cannula has been introduced into the skin. Using a cannula generally results in far less trauma to the facial tissue, reducing bruising, bleeding and swelling at the treated site.
One of the key advantages of using a blunt-tipped cannula is reducing the risk of causing a penetrating injury to vessels such as veins and arteries. The consequences of dermal filler being injected into these structures can have disastrous consequences such as blindness, tissue death and permanent scarring. Because these vessels tend to be pushed aside by the blunt end of the cannula as it passes through the tissues, there is less chance of an arterial or venous injury. Additionally, clinicians can feel more excellent resistance in the path of the cannula. This acquired feel allows the clinician to manipulate and change the cannula’s direction and the amount of pressure required to inject the dermal filler.
Needles
Needles are shorter, more rigid and sharp. Work with needles will require the injector to pierce the skin several times down to where the filler is to be placed. The fine pointed tip requires minimal pushing force to channel the needle to the correct dermal plane for treatment. Needles allow for a more precise injecting technique for areas such as the lips, cheeks and jawline. While more injection sites are required, they can be relatively pain-free due to the needle size, process, and application of some excellent numbing cream! Treatments with needles often have a slightly longer recovery time than that of a cannula due to the increased trauma to the skin. In addition, needles carry a higher risk of injuries to the vessels as the sharp tip can pierce through these structures, making the likelihood of bruising and bleeding higher than a cannula.
At Aesthetic Allure, we use needles and cannula to create and sculpt our clients’ faces. The needles we use are 27g through to 31g – smaller than an insulin needle! Depending on the area you want to be treated, this will ultimately decide what method your injector will choose. Sometimes, both techniques are employed to create the look you want.
Irrespective of what method we choose, a prescription-grade numbing cream is applied to the complete area that your clinician will treat for comfort. Although there is still some discomfort with both methods, the numbing cream makes it much more comfortable.