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Dermal Filler: Know Your G Prime

Product knowledge is an essential part of creating successful aesthetic results. Every injector should understand which dermal filler to use in each situation, based on their G prime.

With guidance from senior clinical trainer, Dr Raquel Amado, we’ve produced this quick reference guide to dermal fillers and G prime.


What is G prime?

G prime – also written as G’ – is one of the key rheological properties of dermal filler. It refers to the viscosity and elasticity of the product. Essentially, it’s a rating that indicates how runny and pliable a filler is.

How is dermal filler G prime measured?

Dermal fillers are given a G prime rating based on their fluidity and flexibility. The lower the rating, the more watery and flexible the filler is. Conversely, the higher the G’ is, the denser and sturdier the filler.

Does G prime indicate how long filler lasts?

Whilst it is not intended as a measurement of longevity of filler results, G prime can be used to give an indication as to how long they will last.


Dr Raquel talked us through this using the Juvéderm Vycross range of hyaluronic acid-based fillers as an example, as this is the collection we use when training our Level 7 and 1:1 students. She recommends taking a photo of the full product range to help with remembering each of them and the order from lowest to highest G’.

“As a rule of thumb, the lightest – so the fillers with the lowest G prime, with less hyaluronic acid – is going to last less time than filler that has a high G prime and more concentrated hyaluronic acid,” she advises.

“For example, in the Vycross range, the lightest of your fillers is going to be Volite and that’s a skin booster. Although it’s a cross-linked product, it’s only going to last you about 3 to 6 months.

“Then we have Volbella and that’s probably going to last you about 6 to maybe 9 months. Obviously this is going to be dependent on lifestyle, metabolism – all of those things that can affect the duration of each patient’s results.”

“Next you’re going to have Volift which is probably going to last you about 9 months to a year. You’re going to have Voluma which will last around 12 to 18 months, then you have Volux which can last up to 24 months.”


Learning more about dermal fillers

The Level 7 Diploma in Botox and Dermal Fillers fully prepares you for a career in aesthetic medicine. This includes learning everything you need to know about the different products you’ll be using. 

From how they handle and where they should be used, to the best fillers for each treatment area, you will be fully instructed in both the theory and practical side of product selection.

Our leading eLearning experience is backed with hands-on tuition from highly skilled clinical mentors, for the ultimate in holistic learning and real-world, clinical experience.

For those of you who want to understand more about the practical applications of dermal fillers, our 1:1 Injectables Training Sessions provide the perfect opportunity. Simply choose the area you wish to focus on, book your slot and you’ll enjoy guided mentoring from knowledgeable aesthetics specialists. Be sure to ask them as many questions as you can think of to really get the most out of your time with them!

To find out more about the different types of aesthetic medicine training courses we offer and find the perfect fit for you, book a call with our head of student recruitment, Deneal Basi. He’ll be happy to answer your questions and discuss your requirements. Then he can point you in the best direction for starting your journey towards aesthetics excellence!