Masseter Botox Korea: Units, Timing and Price in Seoul

My name is Dr. Hongseok Kim. I am a board-certified dermatologist with 21 years of practice, and at VOS Dermatology in Gangnam I see every patient myself, from the first look at the jaw to the last injection point, one person at a time. Messages from abroad about a "square jaw" or a "wide lower face" arrive almost every week, and the honest answer depends on something you cannot see in a photo: how big and how strong your chewing muscle is.

The short answer on masseter botox Korea: it is a botulinum toxin injection into the masseter, the chewing muscle at the angle of the jaw, which relaxes the muscle so it gradually becomes less bulky and the lower face looks softer and narrower. At VOS it is listed as a 75-unit treatment. This guide is for travelers who want to know whether their jaw width is really muscle, how long the change takes, and what it costs in Seoul.

What the masseter is, and why it widens the face

The masseter is a thick, rectangular muscle that runs from the cheekbone down to the angle of the lower jaw. It is the main muscle that closes your mouth with force. Put your fingertips just in front of your earlobes and clench your teeth: the firm bulge that pops out under your fingers is the masseter.

In some people this muscle is naturally large. In others it has grown from habits such as clenching during the day, grinding at night or chewing gum often. A bulky masseter makes the lower third of the face look square or heavy, especially from the front and in photos taken at a slight angle.

Botulinum toxin blocks the nerve signal that tells a muscle to contract. When the masseter works less, it gradually shrinks, much as any muscle does when it is used less. That shrinkage is what slims the jaw. So jaw botox in Korea is really a muscle treatment with a contour effect, not a fat or bone treatment. I explain how botulinum toxin works across the whole face, including brands and safety, in my guide to Korean botox; this article stays on the jaw.

Who masseter botox suits, and who it does not

The most reliable way to judge candidacy is a hands-on check while you clench. Masseter botox tends to suit you if:

• A firm bulge appears at the jaw angle when you clench
• Your lower face looks wider than your cheekbones in photos
• You clench or grind and wake up with a tired or tight jaw
• You want a softer jawline without surgery or downtime

It is less likely to help, or needs a different plan, if:

• Your jaw width comes mainly from bone structure
• The fullness is soft fat along the jawline or under the chin
• The lower face looks heavy because skin and tissue are sagging
• You are pregnant or breastfeeding, or have a muscular or neurological condition

For fat along the jaw and under the chin, an injectable that reduces fat cells answers the question better than toxin. I compare those options in my article on fat dissolving injections in Korea, and the product details are on the V-Line Slim Injection page. When the concern is a dropping jowl, the right conversation is lifting, which my guide on what Ultherapy is covers.

Units, onset and how long it lasts

Here is what the treatment looks like in numbers. The timeline figures below are general and vary from person to person.

The important line in that table is the gap between the muscle relaxing and the face looking slimmer. At 2 weeks your clench will feel weaker, but the jaw may look much the same in the mirror. The contour change comes as the muscle loses bulk, which is slower.

For a traveler this matters. If you are in Seoul for five days, you will fly home before you see the result. That is fine, as long as you know it in advance and do not judge the treatment in the airport mirror.

Worth knowing: Masseter botox slims muscle, not bone or fat. If your jaw is wide mainly because of bone structure, the visible change will be modest, and a higher dose will not change that. I would rather tell you this at the consultation than inject units that cannot answer your concern.

What it does beyond the jawline, and what it does not

Because the masseter is the strongest chewing muscle, relaxing it has effects beyond shape. Many people who clench feel less tension and fatigue in the jaw. Some who grind at night notice they wake up with a looser jaw. As general knowledge, this is a reasonable use of the treatment, but it does not remove the cause of grinding, and it does not replace a night guard or a dental assessment.

There are also things masseter botox does not do. It does not tighten loose skin or lift the jowls. It does not remove fat under the chin. It does not change the bony angle of the jaw. And it does not make the face look smaller overnight.

Two side effects deserve a plain mention. Chewing tough food can feel like more effort for a few weeks. Temporary redness, swelling or bruising at the injection points can occur and usually clears within days. Less commonly, an uneven smile or a hollow look can appear when the dose or depth is off, which is why placement matters more than the number on the vial.

What the visit looks like in Seoul

Consultation. I ask you to clench and relax a few times while I feel both sides. Many people have one masseter that is stronger than the other, often on the side they chew with. I also look at the salivary gland area in front of the ear, the fat pad along the jaw and the skin quality, because each of these changes the plan.

Planning. We agree on the areas and the units before anything is prepared. You will know which product is used; VOS primarily uses Xeomin, a purified botulinum toxin.

Injection. The injections take about 10–15 minutes with a very fine needle. Most people describe small pinches and a brief pressure. You return to your day straight after.

Aftercare. For 4 hours, do not lie down or press on the treated area. On the day of treatment, skip intense exercise, saunas and alcohol, and do not rub or massage the jaw. A walk around Dosan Park or dinner in Gangnam is fine.

Masseter botox price at VOS

The masseter botox price question is usually the first one in a message. Below are the relevant items from our official English price list, copied exactly. All prices are in KRW before 10% VAT, apply to all nationalities and may change without prior notice, so please check the current price list before you travel.

• Masseter Botox, 75 Units: ₩400,000
• Skin Quality Botox – Jawline, 25 Units: ₩200,000
• Salivary Gland Botox, one area: ₩220,000

These are three different items. Masseter Botox is the jaw-slimming treatment this article describes. The other two are separate lines on the list for different purposes, and whether either fits your case is decided at the consultation. All figures are before 10% VAT and may change; confirm them on the pricing page or with us on WhatsApp before booking.

If you are also thinking about the shoulders, trapezius relaxation is priced separately, and I explain it in my guide to trap botox in Korea. Some visitors plan both on one trip.

How I approach masseter botox at VOS

My aim is a lower face that looks softer from the front while your smile and your chewing still feel like yours. That starts with anatomy, not a template. The two masseters are rarely identical, so I plan each side separately and adjust the points to where the muscle is thickest.

I use officially approved products in exact doses, and I tell you the product and the units before we begin. The price you see corresponds to that plan. The wider range of areas we treat with toxin, from expression lines to the jaw and body, is on the botulinum toxin treatment page.

I will also tell you when masseter botox is not the answer. If your width is mostly bone, fat or sagging, I will say so and explain what would address it instead. Sometimes the most useful thing I can do at a consultation is to recommend less.

Before you message us

The most helpful thing you can send is two photos: your face from the front at rest, and your face from the front while clenching your teeth. Add your travel dates, whether you clench or grind, and any past toxin treatment with the product and units if you know them. With that, I can tell you whether masseter botox is likely to help and how it fits into your stay.

Results, timing and recovery vary from person to person. Nothing here replaces an in-person consultation with a dermatologist.

Send your photos and dates on WhatsApp, and our team will reply with a clear plan and quote before anything is scheduled.

Results, timing and recovery vary from person to person. This article is general information from VOS Dermatology Clinic and does not replace an in-person consultation. Any prices mentioned are from the clinic’s official price list (KRW, before VAT) and may change.