Imported fillers vs Korean fillers — what is actually different?

 

During filler consultations,this is one of the most common questions I hear.

 

“Is Juvederm better?”
“Does Restylane last longer?”
“Is it true that Korean fillers dissolve quickly, while imported fillers last longer?”

 

But this question is actually harder to answer in one simple sentence than many people think.

 

That is because fillers cannot be classified only by whether they are imported or Korean-made.

 

Even among the same hyaluronic acid fillers,the actual feel can vary quite a lot depending on whether the product is monophasic or biphasic,what its G’ value is,how cohesive it is,and how much water it tends to attract.

 

So today, I would like to explain the difference between imported fillers and Korean fillers from the perspective of filler properties.

 

This topic is a little more physical than medical, so it may not feel very easy at first.

 

Still, when choosing a filler, it is much more helpful to understand what actually makes a difference rather than looking only at the price or brand name.

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Do imported fillers last over a year, while Korean fillers last only 6 months?

This is one of the most common misunderstandings.

 

To start with the conclusion, it is difficult to divide them that simply.

 

Most dissolvable fillers, meaning hyaluronic acid fillers, gradually break down over time.

 

The duration is affected by the product structure, degree of cross-linking, injection depth, and movement of the treated area.

 

It cannot be explained only by the country of origin.

 

Also, lasting longer does not necessarily mean that the original volume remains exactly the same as when it was first injected.

 

During the filler degradation process, changes such as surrounding tissue response, matrix deposition, and fibrous capsule formation may also occur.

 

So the volume retention we see clinically may not be exactly the same as simply asking whether the filler has broken down or not.

 

In other words, rather than saying “imported fillers last longer,” it is much more important to ask
“what type of filler structure was used, and where was it injected?”

How should filler types be classified?

 

There are several ways to classify fillers.

 

First, they can be broadly divided into dissolvable fillers and fillers that are less easily dissolved.

 

A representative dissolvable filler is hyaluronic acid, or HA filler.

 

Common examples of less easily dissolved fillers include calcium hydroxyapatite, or CaHA, and polycaprolactone, or PCL-based fillers.

 

Then, even within hyaluronic acid fillers, they can be divided into monophasic and biphasic types.

 

Within those categories, we also look at properties such as G’, G’’, G*, swelling factor, and cohesivity.

 

The terms may sound a little difficult.

 

Simply put, we are looking at how firm the filler is, how elastic it is, how well it maintains its shape, how easily it spreads, and how much water it attracts.

 

That is why even among HA fillers, a product that works well for the lips and a product that works better for the nose or chin may have very different characteristics from the beginning.

Monophasic vs biphasic — why does this matter?

 

This is another part that many people find confusing.

 

Some people simply memorize it as monophasic fillers being soft and biphasic fillers being firm.

But in reality, it is not that simple.

 

Review papers explain the difference between monophasic and biphasic fillers based on particle structure and dispersion pattern.

 

In histologic studies, biphasic HA fillers appeared relatively pool-like within the dermis, while monophasic smooth gels tended to distribute more evenly and broadly within the tissue.

 

So it may be easier to understand it this way:

monophasic fillers tend to spread more evenly within the tissue, while biphasic fillers tend to exist as more distinct particles or clusters.

 

That is why the preferred product may differ between areas that need a natural spread in a shallow layer and areas that require more shape retention.

 

However, it would also be incorrect to assume that all monophasic fillers are soft and all biphasic fillers are firm.

 

The actual feel needs to be judged together with the degree of cross-linking, concentration, and overall physical properties.

What kind of filler lasts longer?

 

Hyaluronic acid fillers generally break down over time.

 

On the other hand, CaHA and PCL-based fillers are often described as lasting relatively longer.

 

However, this also depends on the product, indication, and injection layer, so it is important to be cautious about saying something like “it definitely lasts for several years.”

 

The important point is that a longer-lasting filler is not always a better filler.

 

A filler may last longer, but it may also be more difficult to shape as desired or feel burdensome in thinner areas.

 

A good filler is not determined by duration alone.

 

Safety, suitability for the treatment area, and predictability should all be considered together.

 

This is a point commonly emphasized in multiple review papers.

Why do we look at G’, G’’, G*, and Swf?

 

From here, the discussion becomes a little more about physical properties.

 

But these factors are more important than many people think.

 

G’ can be understood simply as elasticity. It is the force that allows the filler to return to its original shape after being pressed.

 

So fillers with a high G’ value are often considered for areas that require stronger shape retention.

 

G’’ is related to viscosity.

 

It is connected to the tendency to flow and how the filler behaves under shear force.

 

G* can be understood as an overall complex strength.

 

Swelling factor refers to how much water the filler attracts and how much its volume can increase.

 

In thin areas, this property needs to be considered more carefully.

 

Cohesivity refers to how well the filler tends to stay together within the tissue.

 

This can also affect line formation and shape maintenance.

 

In other words, looking at these properties before simply looking at the brand name helps us choose a filler that is more suitable for each area.

Why do filler selection standards differ by area?

 

In thin and delicate areas such as the forehead, under-eyes, or neck lines, softer products that create a natural line may be more suitable.

 

On the other hand, in areas such as the nose, chin, and chin tip, where shape retention and support are important, a product with more structural support may be considered.

 

This is because after filler is injected into the skin, it is affected by different types of forces such as shear, torsion, stretch, and compression.

 

The lips are different again. For the lips, not only the shape but also movement and texture are important.

 

So if a product is too firm or has a strong tendency to swell, the result may feel less satisfying.

 

That means the first question should not be “which filler is the best?” but rather “which filler should be used for which purpose and in which area?”

Are imported fillers better than Korean fillers?

 

This question needs to be answered carefully.

 

Major review papers currently available mainly compare fillers based on product properties, cross-linking methods, structure, and behavior within tissue.

 

They do not present a simple conclusion such as “imported fillers are superior because they are imported.”

 

In my opinion, it is difficult to say that imported fillers are always better.

 

However, it is true that imported filler brands often have more subdivided product lines, more accumulated clinical experience, and higher brand recognition.

 

For example, products such as Restylane and Juvederm, which frequently appear in papers and histologic comparisons, have relatively more published data on their characteristics.

 

But that does not mean Korean fillers are clearly inferior.

 

The actual outcome is influenced much more by the treatment area, filler properties, amount used, injection layer, and the clinician’s judgment than by the nationality of the brand.

 

A good filler does not mean there is one absolute number-one product.

 

It means choosing a product with properties that best match the specific purpose and treatment area.

 

Even a very good product can look obvious if it is injected too superficially in an area where it should not be placed shallowly.

 

And even a famous product can feel too firm, cause swelling, or create an unwanted shape if it does not suit the area.

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3-Line Summary

Fillers should be evaluated first by their properties,
such as whether they are dissolvable,
whether they are monophasic or biphasic,
and their G’, G’’, G*, Swf, and cohesivity,
rather than simply by whether they are imported or Korean-made.

 

Each area requires different characteristics,
so the forehead, under-eyes, lips, nose, and chin
cannot all be treated according to the same standard.

 

There is not enough evidence to conclude that imported fillers are always superior.

The result is more strongly influenced by product properties, suitability for the area,
and injection design.

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Study References

 

The Rheology and Physicochemical Characteristics of Hyaluronic Acid Fillers: Their Clinical Implications

 

Rheologic and Physicochemical Properties Used to Differentiate Injectable Hyaluronic Acid Filler Products

 

Comparative Histology of Intradermal Implantation of Mono and Biphasic Hyaluronic Acid Fillers

Injectable Fillers: Current Status, Physicochemical Properties, Function Mechanism, and Perspectives

 

This was Director Won Dae-han.

 

Thank you for reading.

 

※ This article is intended for general medical information only. Diagnosis and treatment plans may vary depending on each individual’s facial structure, skin condition, and treatment area.

 

※ All procedures may involve side effects depending on the individual, including swelling, bruising, asymmetry, inflammation, nodules, and vascular-related complications. Please make a careful decision after sufficient consultation.