Dermal fillers - one of the most popular and executed minimally invasive aesthetic treatments worldwide - seem simple enough . Find an area you need filling, stick the needle in, and inject.
Or is it?
What are dermal fillers?
Dermal fillers are thick gel-like substances that are inserted under the skin. They can fix a number of common aesthetic flaws . They:
- smooth the deep under-eye circles,
- raise the cheekbones,
- volumise the lips,
- smooth the lip lines as well as nasolabial folds and
- rejuvenate the hands.
There are 2 main types when it comes to dermal fillers. They are the hyaluronic acid (HA) and the non-HA class of fillers .
Hyaluronic acid (HA)
Hyaluronic acid is a natural substance found in your body . In fact, it is present in many parts of your body. They can be found in:
- some cartilage,
- joint fluids,
- skin tissues,
- soft connective tissues,
- the fluid around your eyes.
Extracted and reformulated, HA has now become one of the most popular types of injectable fillers . Generally, it is used to improve skin contour and decrease skin depressions due to scars, damage or lines. By getting fillers, you can see substantial improvements to:
- Acne scars
- Cheek depressions
- Crow's feet at the corner of your eyes
- Deep smile lines that run from the side of the nose to corners of the mouth (also known as nasolabial furrows)
- Frown lines between the eyebrows
- Marionette lines at the corners of the mouth
- Redefining lip border
- Scars including burns, acne and those caused by wounds
- Smoker's lines; vertical lines around the mouth
- Some facial scars
- Worry lines that run across your forehead
Within the HA segment, a myriad of types exists with varying viscosity and densities that give them different properties such as:
- deep in the fat to give structure,
- soft enough to be placed near the skin's surface - use to smoothen out wrinkles or hydrating skin without causing lumps.
Non-hyaluronic acid (Non-HA)
Non-HA fillers consist of - as the name says - non-HA compounds . Examples of non-HA fillers are:
This dermal filler was first used in dentistry and reconstructive surgery . It consists of calcium hydroxylapatite (CaHA), a type of mineral naturally found in the human bone. Biosynthetically produced, this product does not use any animal or its products . Thus, reducing the risk of any allergic reactions that you may face.
Known as a bio-simulator, the poly-L-lactic acid (PLLA) in Sculptra is a synthetic polymer. This type of filler is biodegradable and non-toxic .
In this dermal filler, it consists of :
- carboxymethyl cellulose (CMC) - a short-lasting filler component and
- poly-caprolactone (PCL) - a long-lasting bio-resorbable soft medical polymer.
Hence, these make Ellansé a hybrid bio-stimulating filler. The CMC gives an instant volume lift while the PCL stimulates collagen production.
HA fillers VS non-HA fillers
That said, here are the 2 things that separate non-HA fillers from the HA fillers:
- Non-HA fillers CANNOT be reversed. This is unlike HA fillers which can be dissolved with hyaluronidase (an enzyme) . There are no reversals when it comes to Non-HA fillers.
- Non-HA fillers last longer and generally stimulate more collagen.
The above points sum up the importance of this article - complications that result from fillers can be potentially reversed, but that is if HA is used.
Yes, there are complications, and some are pretty scary! Does that mean that non-HA products have no role? Not exactly. Non-HA fillers have different properties and when used correctly and in good hands, produce lovely results for the right indications.
Do visit a doctor to get recommendations of which type of dermal fillers your concerns are suitable for.
Fillers provide much-needed support to weakened skin structure
So before we get to these complications, let's look into several other areas such as:
- what are fillers used for
- how should we go about choosing what is best for each indication
To start, you can think of the face like a tent, or a house. We have bony structural support and deep fat pads that add to that support. Apart from that, there is the overlying roof of superficial fat and skin that drapes over this support.
As you age, you lose approximately 1% of this structural volume a year. On top of that, you will also lose collagen at a rate of about 1% a year after 30 . To make matters worse, Asians are genetically lacking in cheek support and chin projection .
What can you do to a face that is losing volume and support?
The only answer is – replace that volume. That is what fillers are used for primarily . Harder, stronger fillers are placed deep to mimic lost skeletal support. This emulates your natural existing bony structure thus, lifting the overlying canvas of superficial fat and skin. Place a softer filler here and results will be poor – buildings need proper mechanical support from pillars or face collapse. These mechanics apply similarly here.
The softest fillers, however, do have their role. Typically placed at the undereye area, it is used to mimic the very little soft tissues that can be found there. In other words, the fillers here need to be soft and mouldable enough to blend. But, at the same time, it should not be visible through the thin skin. Place a hard filler here, and you will see and feel lumps .
All the other fillers lie somewhat in between these two types. With that, they are able to help fill the layers between the skin and bone.
Then, of course, there are the skin boosters. Skin boosters are the softest and most watery of the lot. Placed most superficially in the skin, it hydrates and supports the uppermost part of the skin.
You can therefore see the potential complexity in filler type selection. There are so many types to choose from, but where do we use what? This question is of utmost importance as it helps to avoid any possible complications. To add on, there is also the question of how do we do it. If you are in the right hands, the risk of complications can definitely be reduced.
Possible complications: how the fillers can go awry
Fillers are, when in the right hands, an exceptionally safe procedure. Regardless, there complications you should know about.
Here are some ways to prevent and manage complications:
Bruising at the site of injection
Avoiding anti-platelet or blood-thinning medications a week before and after treatment
Icing helps to reduce chance of bruising
Using cannulas or blunt tip needles instead of sharp needles to reduce injuries to blood vessels 
Discomfort during the procedure
Applying topical numbing cream prior to the procedure
Using local anaesthetic injections 
Icing of the injection sites will reduce discomfort
Swelling for a few days after the procedure
Apply cold compress immediately after the procedure
Visible needle marks for a few days
- Icing as well as moisturising the area post-procedure helps
- Squeezing out any fillers by creating a small entry through the skin with a needle.
- Dissolving with hyaluronidase if it is an HA filler 
- Taking oral antihistamines or steroid medication
Reactivation of cold sores
- If you have a history of herpes infections, pre- and post-procedure oral anti-viral medications must be taken
- Ensure clean and aseptic techniques during the procedure
- Avoid touching the site of injection after the procedure
- Topical and oral antibiotics help manage any existing infection
These complications are minor and completely reversible, with no lasting effects on patients. If you experience any complications and are unsure about what to do, consult your doctor.
The more severe, but rare, complications
There are, however, rarer and scarier things that can go wrong with fillers. These complications are something we wish would not happen to anyone. It includes but are not limited to :
Vascular blockage by a filler
- Skin necrosis (skin cell death)
Long-term inflammatory disorders
Vascular occlusion by fillers can happen, causing dire consequences. However, it is considered rare with the accepted risk rate at 1 in every 100,000 cases .
This occurs when a filler is:
- directly injected into a blood vessel or
- injected in such large amounts that it ends up compressing the nearby vessels
When this happens, the vascular network beyond the compression may get its blood supply cut off. Consequently, the organ ends up dying . According to the location, it may lead to:
- in the eye, blindness;
- in the brain, a stroke; and
- the skin, skin death.
The rates of occurrence of rarer complications
The rates, though considered rare occurrences, have gotten higher as many countries have non-medical practitioners injecting fillers indiscriminately at cheaper rates. Patients are often unaware of the possible complications that can arise. Also, they are not aware of the need for experienced practitioners when undergoing such medical procedures.
If you suspect that you are suffering from any of the complications, consult your doctor as soon as possible.
How can vascular issues be prevented?
I'll give it to you straight: you can actually reduce the risks, but you will not completely get rid of the risks. Regardless, here are some ways the risks can be reduced:
- Choosing a good doctor with good knowledge of the body's anatomy
- Selecting the right fillers and volume to use
- Slow meticulous injections
- Good technique
- Using blunt cannulas where possible
If and when things go wrong, can they be reversed? Depends.
If your fillers are HA injections, the answer is – maybe. For vascular occlusion affecting the skin and leading to skin death, complete reversal with minimal scarring is possible with hyaluronidase. Meanwhile, for those affecting the eyesight, no definitive study has shown that it is effective at reversing retinal artery vascular occlusion by a filler.
But not all areas of the face are of such high risk. It is good to note that the riskiest places for such complications are the glabella and nose. The reason behind it is that there is a plentiful amount of the vascular networks there. Besides, the tight skin makes it easy for needles and cannulas to penetrate and enter them accidentally .
Vessels are everywhere. Although the other parts of the face are considered safer, that does not mean that it is risk-free! So, precautions must always be taken.
What about the granulomas and biofilms?
These complications are longer-term and do not occur immediately – unlike the vascular issues above.
They may occur many weeks after injection, typically because of:
- the body’s rejection of the filler material (granulomas) or
- a seeded infection to the filler from elsewhere (biofilm).
These result in a persistent, firm and often inflamed lump. Generally, it forms at a rate of 0.02% - 0.4% of the time with HA fillers . Perhaps because of its bio-compatibility, Radiesse has not been shown to cause any definitive granulomas.
It is good to note that these late complications are rare and can be prevented with good and aseptic technique. But, they can still occur in susceptible individuals for reasons that are not clear. Despite that, they can be managed by :
- oral antibiotics and steroids,
- injected steroids and hyaluronidase, and
- surgical removal of the lumps in some cases.
Here are some important tips
As you can see, fillers are no simple feat. Before we ever stick a needle into the skin, it is important that doctors:
- have proper knowledge in applied anatomy,
- select appropriate and suitable products,
- have good technique selection and performance,
- recognise complication early together with the patient, and
- stay updated on complication management principles.
As doctors, we are here to perform the procedures to the best of our abilities. Also, we have to have the knowledge to recognise that complications can happen. When they do happen, we will help to manage these complications appropriately.
For patients, you should choose wisely and seek treatments from certified and experienced doctors who:
- have the ability to recognise complications,
- can manage the complications from a procedure,
- will perform the procedure properly.
Be sure to inform your doctor as soon as possible if you are suffering from any filler complications. That way, the doctor can access your condition and suggest ways for you to reduce the side effects.
Dr Shane Abucewicz Tan graduated from the National University Of Singapore with a Bachelors in Medicine and Surgery. Also, he attained his post-graduate surgical membership at the Royal College of Surgeons, Edinburgh. Besides that, he understands the unique and dynamic nature of each patient. To fit his patients' changing needs, all his treatments are tailored at each medical consult.
1. Vedamurthy M, Vedamurthy A. Dermal fillers: Tips to achieve successful outcomes. Journal of Cutaneous and Aesthetic Surgery. 2008;1(2):64. doi:10.4103/0974-2077.44161
2. Liu K. Dermal fillers: The good, the bad, and the dangerous - Harvard Health Blog. Harvard Health Blog. Published July 15, 2019. Accessed January 31, 2020.