Fillers & Botox

Filler: Injections That Fill Sunken Areas, Types and Side Effects

Q: Will filler lift sagging cheeks?

No. Filler is a procedure that fills the volume of sunken areas. Sagging is explained in the lifting selection criteria.

Q: How does filler differ from skin boosters?

Filler fills the volume of sunken areas. Skin boosters are procedures intended to address the condition of the skin itself, such as texture, elasticity, and hydration. Their purposes differ, so one cannot replace the other. Details are in Types of Skin Boosters and Their Differences.

The key to filler is 'design'

Filler is a procedure in which a gel-type material is injected into sunken areas to fill in volume.

About the Doctor Request a Consultation

Female model with bare shoulders touching her hand to her cheek

Table of contents for this page

What is filler?
What concerns is filler used for?
What can't filler resolve?
Which areas is filler used in?
Which fillers does Face Plus Plastic Surgery use?
How is the filler procedure done? Does it hurt?
Can filler be dissolved if I do not like it?
Do you overdo filler?
Face Plus Talk
Frequently Asked Questions
Related FacePlus TV Videos
Related surgeries and procedures worth looking at together
References

What is filler?

Filler is a procedure in which a gel-type material is injected into sunken areas or beneath deep wrinkles to fill in volume.

The name is familiar, but what is inside is not well known.

Filler is not the name of a single product. It refers collectively to several products with different ingredients.

The fillers used at Face Plus Plastic Surgery are of two kinds by ingredient.

Hyaluronic acid (HA, an ingredient that holds on to water) filler: there is an injection that dissolves it.
PCL (polycaprolactone, a synthetic ingredient that slowly dissolves in the body) filler: there is no medication that dissolves it.

The difference you should know first is whether it can be dissolved.

How do hyaluronic acid and PCL differ?

Mechanism

Hyaluronic acid filler is a product made by turning hyaluronic acid into a gel. It takes up volume at the injection site. It can be dissolved by injecting hyaluronidase (an enzyme that breaks down hyaluronic acid). PCL filler is a product containing polycaprolactone microspheres (very small particles). Hyaluronidase does not act on PCL filler, and there is no medication that dissolves PCL filler.

In plain terms — With hyaluronic acid filler, if you are not satisfied or a problem occurs, a dissolving injection can be used. PCL filler has no dissolving injection. That is why which filler to use and where is decided carefully at the start.

Type	Hyaluronic acid (HA) filler	PCL filler
Ingredient	Hyaluronic acid	Polycaprolactone (PCL)
Dissolving medication	Yes (hyaluronidase)	None
In-clinic products	Belotero, Juvederm, and Belast series	Ellansé
Duration

A detailed explanation of whether it can be dissolved is in Can filler be dissolved if I do not like it?.

It fills the shadows of the face

When wrinkles form or volume sinks in the face, shadows appear. Together with lifting, filler is an injection procedure used to reduce these shadows, fill uneven areas, or raise the nasal bridge, and the shape can be refined immediately by injection without an incision.

It is important to receive filler from a medical team with a lot of experience performing the procedure. Face Plus chooses the product and amount to suit the treatment area and shapes the result naturally.

Face PlusFace Plus offers a customized procedure that uses only the amount of filler that is truly needed

Female model sitting with her hand under her chin

Filler, a non-surgical method, is made of a component found in the human body that is absorbed and disappears over a certain period of time. To minimize side effects, we inject while checking the position of blood vessels.

However, because the volume design differs greatly depending on the aesthetic sense and technique of the medical team, it is best to receive it from a specialist with a lot of experience. At Face Plus, a suitable filler is selected according to your skin type and the treatment area.

Immediate volume effect
Non-surgical, with daily activities possible right after the procedure
Approved fillers
Natural proportions through one-on-one tailored procedures
Can be done for brides-to-be ahead of an important day

Face PlusThe key to filler is 'design'

Natural proportions through a one-on-one design tailored to each individual's face.

Dr. Park Jung Keun performs the procedure quickly, using know-how and technique built on his extensive procedural experience.

Easy, quick wrinkle improvement
Natural contour design
A procedure done by injection without an incision
Use of approved products
Natural proportions through one-on-one tailored procedures

What concerns is filler used for?

Filler is considered for filling sunken areas that cast shadows, such as the cheeks or under the eyes, and deepened nasolabial folds.

Read the list below while thinking about which part of your face bothers you most when you look in the mirror.

When the temples, front of the cheeks, or under the eyes are sunken and cast shadows
When the nasolabial folds or marionette lines (lines running from the corners of the mouth down to the chin) have deepened
When you want to improve the shape of the chin or forehead
When the lips have become thinner

Sunken and sagging are different

They may look similar in the mirror, but the solutions differ.

If the cause of the shadows is sinking, filling is the right approach. If the cause is sagging, lifting is the right approach.

There are also cases in which the two are mixed. That is why, at the consultation, we first look at which is the main cause.

A Word from the Doctor
"Nasolabial folds should not be thought of as something corrected simply with nasolabial filler or nasolabial fat grafting; it is important to find the solution carefully according to the cause."

Face PlusFiller Is Recommended for People Like These

When the face has little fat so the contours stand out
When you need to improve facial wrinkles caused by aging
When you are concerned about a hollow or flat forehead
When you are very stressed about looking older
When you want a more three-dimensional facial line

Female model touching her hand to her cheek and jawline

What can't filler resolve?

Lifting sagging tissue back into place is not what filler does. Wrinkles that form when you smile or frown, and skin texture, are mainly handled by other procedures.

Female model holding a hand mirror and touching her chin

How do filler, skin boosters, and botulinum toxin differ?

Filler, skin boosters, and botulinum toxin (commonly called Botox) do different things. They cannot replace one another. This does not mean one is better than another.

Procedure	What it addresses	Details
Filler	Fills the volume of sunken areas	This page
Skin Booster	The condition of the skin itself, such as texture, elasticity, and hydration	Types of Skin Boosters and Their Differences
Botulinum toxin	Reduces muscle movement to address expression lines	Botulinum toxin procedure information
Thread lift and lifting surgery	Lifts sagging tissue upward	Lifting Selection Criteria

Related information by concern:

If the cheeks and jawline are sagging: thread lift procedure information, mini facelift surgery information, facelift surgery information
If the skin has become thinner and fine lines have increased: Types of Skin Boosters and Their Differences
Wrinkles that appear only when you smile or frown: botulinum toxin treatment is considered
If the area under the eye bulges instead of being sunken: lower eyelid fat repositioning surgery information, lower blepharoplasty information

Which areas is filler used in?

Filler is used in the cheeks, temples, nasolabial folds, under the eyes, forehead, lips, chin, and other areas, and the areas are decided at the examination.

Area	Patients often say	What we look at first at the consultation
Cheeks · front of the cheeks	My cheeks are sunken and I look tired	Whether the area has sunken or has dropped
Temples	My temples look hollow	How sunken they are and the overall facial contour
Nasolabial folds · lines around the mouth	My nasolabial folds have deepened	Whether the area below the fold is sunken, or the upper cheek has dropped and folded
Under the eyes	The area under my eyes is sunken and shadowed	Whether it is sunken or the fat bulges. This is an area with thin skin
Forehead	My forehead looks sunken	It is a wide area, so how to divide the amount and depth
Lips	My lips have become thinner	The original lip shape and the upper-to-lower ratio
Chin	My chin looks short	The proportions of the whole face

Face PlusFiller treatment areas

Filler treatment areas — forehead, under-eye aegyo-sal, cheeks/front cheekbones, lips/mouth corners, chin/weak chin, fine lines, nose, nasolabial folds, neck lines

Which fillers does Face Plus Plastic Surgery use?

Fillers used at Face Plus Plastic Surgery — packaging of Belotero, Juvederm, Belast, and Ellansé products

Face Plus Plastic Surgery uses eight hyaluronic acid fillers and one PCL filler, selected according to the area and condition.

There are many product names, which can be confusing, so we have grouped them by product line.

This is not a ranking of which product is better.

Product line	In-clinic products	Main ingredient	Dissolving medication
Belotero	Belotero Soft · Balance · Volume	Hyaluronic acid (HA)	Yes
Juvederm	Juvederm Volift · Volbella · Voluma	Hyaluronic acid (HA)	Yes
Belast	Belast Soft L · Ultra L	Hyaluronic acid (HA)	Yes
Ellansé	Ellansé	Polycaprolactone (PCL)	None

Belotero (BELOTERO)

Belotero Soft · Balance · Volume

Juvederm (JUVÉDERM)

Juvederm Volift · Volbella · Voluma

Juvederm product packaging on a purple background

Belast (BELAST)

Belast Soft L · Ultra L

Belast Ultra L 1.0 mL product packaging and syringe

Belast Ultra L 3.0 mL product packaging and syringe

Ellansé (ELLANSÉ)

Polycaprolactone (PCL) filler — Ellansé S · M

QTfill

QTfill Signature Fine · Deep · Sub-Q

Approved purpose of use, areas where it must not be used, and duration of effect for each product

Which product to use is not chosen by the patient; the doctor decides it by looking at the area and the condition of the face.

You are welcome to ask at the consultation which product is right for you.

How is the filler procedure done? Does it hurt?

At the consultation we look at the condition of your face and decide the area and product, then give anesthesia and inject.

1. Consultation

We first look at where you are bothered. We separate whether it is sunken or sagging. If another procedure is judged to be more suitable, we will tell you so.

2. Explanation and Consent

We explain the product, the area, and the side effects that can occur.

3. Anesthesia

The anesthesia method and the waiting time

4. Injection

It is injected with a needle or a cannula (a tube with a rounded tip). Which instrument is used and at what depth differs by area.

5. Aftercare Instructions

We explain precautions and symptoms that need to be checked promptly.

How painful is filler?

Pain varies by area. Sensitive areas such as the lips can hurt more.

Some products contain lidocaine (a local anesthetic ingredient). If you are allergic to lidocaine, be sure to tell us at the consultation.

As for how long the procedure takes,

Can filler be dissolved if I do not like it?

Hyaluronic acid filler can be dissolved with a dissolving injection, but there is no medication that dissolves PCL filler.

"Can't it just be dissolved if I don't like it?" This is something we often hear at consultations. The answer depends on the type of filler.

Mechanism

Hyaluronidase (an enzyme that breaks down hyaluronic acid) acts only on hyaluronic acid filler. It does not act on polycaprolactone (PCL) filler, and there is no medication that dissolves PCL filler. If a problem occurs with PCL filler, injection treatment or removal may be needed.

In plain terms — The dissolving injection works only on hyaluronic acid filler. PCL fillers such as Ellansé have no dissolving injection.

Having a dissolving injection does not mean every problem can be reversed. When a blood vessel is blocked, prompt treatment is important. The dissolving injection is also a drug, so allergic reactions can occur.

When you can be filled again after dissolving

Whether we consult on dissolving filler that was injected at another clinic

Do you overdo filler?

The first of our treatment principles is "We never recommend unreasonable surgery," and we apply the same principle to filler consultations.

"Plastic surgery is not art. It is the practice of medicine." This is the treatment philosophy of Face Plus Plastic Surgery.

We fully understand hesitating about filler out of worry that it will look obvious.

Filler looking overdone does not happen only when the amount is large. It can also happen when an area that did not need filling is filled. If you try to resolve an area where sagging is the cause with filler alone, the amount increases.

That is why, at the consultation, we first separate whether it is sunken or sagging. If filler is judged not to be suitable, we will tell you so. If another method is suitable, we will guide you to that method. It is laid out in What Filler Can't Resolve.

A Word from the Doctor
"There are people who say their nasolabial folds became worse after such procedures; it is very important to perform the right procedure on the exact area."

Based on our contouring surgery experience, we design by looking at the proportions of the whole face.

The amount injected at one time and the criteria for dividing sessions

Face Plus Talk

There are truly many different reasons a person looks older.

— Dr. Park Jung Keun, Plastic Surgery Specialist · Face Plus Talk

Dr. Park Jung Keun examining a patient's face during a consultation

There are many, but there is one that is easily overlooked. It is the front cheekbone area. If the middle part of the face is long and flat, you look older. In this case the face also looks long and gives a tired impression. Also, as the front cheekbone area sinks, midcheek grooves often form. In this case you look even more saggy and the nasolabial folds look deeper.

In this case there is an effective rejuvenating approach. It is to lift the sagging skin and fill in volume. With a thread lift, the skin can be lifted firmly without an incision, and with filler or fat grafting, the volume of the front cheekbone area can be filled.

The effects obtainable this way are also varied. The flatness of the front cheekbone area is corrected, so the face looks three-dimensional. The side profile also looks much more refined. Because the volume around the mouth is restored, a protruding mouth looks less prominent. If nasolabial fold filler or fat grafting, or chin filler or fat grafting, is done together at this time, a protruding mouth can be improved even more.

Because sagging nasolabial folds and jawline are corrected, the face looks much firmer. The shadowed or bumpy feeling of the face also improves considerably. As a result, the impression becomes brighter and more three-dimensional, and wrinkles improve, making a much younger-looking face possible.

When we say someone looks older, we think only of sagging, but it is more important than anything to correct the sagging and at the same time add volume to make the face three-dimensional. Natural change can be expected even from a moderate procedure without an incision. Of course, careful and correct surgical planning is essential.

There is no single correct answer for a surgical method. After a thorough consultation, we proceed with a surgical method tailored to each individual. Online Consultation

Frequently Asked Questions

How long does filler last?

How long filler lasts differs by product, area, and person, so it is difficult to give a single number.

Item	Details
Duration by product
When to get it done again

Hyaluronic acid filler is slowly broken down and absorbed by the body. The rate of absorption differs by person, product, and area.

PCL filler is a material made to take longer to break down.

Longer-lasting is not always better. A filler that cannot be dissolved is difficult to reverse, even if you are not happy with the result.

What are the side effects of fillers?

Fillers can cause bruising, swelling, asymmetry (the two sides looking different), and lumps. In rare cases, a blocked blood vessel has led to skin necrosis (death of tissue), loss of vision, or stroke, and such cases have been reported.

This is information you must know before receiving the injection, so we have listed it as it is, without leaving out even the rare events.

Reactions at the injection site

Bruising
Swelling
Redness at the injection site
Tenderness (pain when pressed)

Shape-related concerns

Asymmetry
Lumps that can be felt or seen through the skin
Looking more raised than you wanted
Filler moving to another area (migration)

Conditions that may require treatment

Infection
Hypersensitivity reaction (allergic reaction)
Nodules (palpable lumps)
Delayed nodules (lumps that appear a long time after the procedure)
Foreign body reaction (inflammation that occurs when the body recognizes the filler as a foreign substance)
Skin necrosis due to vascular occlusion
Vision loss due to vascular occlusion
Cerebrovascular complications (stroke) due to vascular occlusion

Do not wait in these cases

If anything feels wrong after the injection, please do not endure it alone.

The changes below are ones you should tell us about without waiting until your next visit.

If your speech becomes slurred, or one side of your face, arm, or leg goes numb or loses strength, call 119 right away.

If you suddenly cannot see well or see double, call 119 or go to an emergency room right away, regardless of clinic hours.

When the skin at or around the treated area turns white, bluish, or develops a purplish net-like pattern
When the pain becomes severe
When blisters form on the treated area
When your vision suddenly becomes unclear or looks abnormal
When an eyelid suddenly droops or you see double
When you have a fever, or the treated area becomes red, swollen, and hot
When swelling is severe on one side only
When a lump can be felt and stays the same or grows, or when a new one appears after some time has passed
When the filler appears to have moved from where it was first placed
When the two sides are still noticeably different after the swelling has gone down

If your skin color changes or the pain becomes severe outside clinic hours, do not wait; go to an emergency room. Tell the emergency room that you received filler, the type of filler (whether or not it is hyaluronic acid filler), the area treated, and the time of the injection.

If you develop hives all over your body, are short of breath, or your lips or throat swell, call 119 or go to an emergency room.

Regarding how to contact the clinic outside clinic hours,

Precautions after filler procedures

Regarding precautions after the procedure (washing your face and makeup, exercise, alcohol, and saunas, and whether you may press or rub the treated area),

Will filler lift sagging cheeks?

No, it will not. Filler is a procedure that fills volume in hollow areas. Sagging is explained in How to Choose a Lifting Procedure.

How are filler and skin boosters different?

Filler fills volume in hollow areas. Skin boosters are procedures intended to address the condition of the skin itself, such as texture, elasticity, and hydration. Their purposes differ, so neither can replace the other. For details, see Types of Skin Boosters and Their Differences.

Can filler be dissolved if I do not like it?

Hyaluronic acid filler can be dissolved by an injection of hyaluronidase (an enzyme that breaks down hyaluronic acid). There is no medication that dissolves PCL fillers such as Ellansé.

References

Beleznay K, Carruthers JDA, Humphrey S, Carruthers A, Jones D. Update on Avoiding and Treating Blindness From Fillers: A Recent Review of the World Literature. Aesthet Surg J. 2019;39(6):662–674. PMID 30805636. doi:10.1093/asj/sjz053
Rho NK, Kim HS, Kim SY, Lee W. Injectable "Skin Boosters" in Aging Skin Rejuvenation: A Current Overview. Arch Plast Surg. 2024;51(6):528–541. PMID 39544509. PMCID PMC11560330. https://doi.org/10.1055/a-2366-3436
Signorini M, Liew S, Sundaram H, De Boulle KL, Goodman GJ, Monheit G, Wu Y, Trindade de Almeida AR, Swift A, Vieira Braz A; Global Aesthetics Consensus Group. Global Aesthetics Consensus: Avoidance and Management of Complications from Hyaluronic Acid Fillers—Evidence- and Opinion-Based Review and Consensus Recommendations. Plast Reconstr Surg. 2016;137(6):961e–971e. PMID 27219265. PMCID PMC5242216. doi:10.1097/PRS.0000000000002184
Alhusain AM, Alsaif M, Alkhathami AM, Alghamdi AM, Alkhunein J, Alqirnas M, Alsubhi RO, Alsalamah S, Alanazi MM, Fathi A, Alghamdi A, Alowid F, Aleissa S. Hyaluronidase Protocol in Management of Hyaluronic Acid Filler-Related Vascular Complications: A Systematic Review and Meta-Analysis. Aesthetic Plast Surg. 2026;50(6):2300–2317. PMID 41249530. doi:10.1007/s00266-025-05431-5
Baranska-Rybak W, Lajo-Plaza JV, Walker L, Alizadeh N. Late-Onset Reactions after Hyaluronic Acid Dermal Fillers: A Consensus Recommendation on Etiology, Prevention and Management. Dermatol Ther (Heidelb). 2024;14(7):1767–1785. PMID 38907876. PMCID PMC11265052. doi:10.1007/s13555-024-01202-3

Dr. Park Jung Keun · Plastic Surgery Specialist, PhD in Medicine

He personally consults on and performs facial aging treatments such as facelift, droopy eyelid surgery, and thread lift. The doctor personally sees you from consultation through recovery.

2004 Plastic Surgery Specialist2013 PhD in Medicine, Seoul National UniversityVice President, Korean Association of Plastic Surgeons

About the Doctor

Medical content reviewed (fact-checked)Treatment by Dr. Park Jung Keun

Other pages in this menu

Volume · Non-surgical Overview Botox Volume · Non-surgical Overview

The content of this page is general medical information provided in accordance with the Medical Service Act, and the effects and recovery time of surgeries and procedures may vary by individual. All surgeries and procedures can cause side effects, so please make your decision only after a thorough consultation with a plastic surgery specialist.

Filler: Injections That Fill Sunken Areas, Types and Side Effects