Masseter Botox

Masseter Botox in Seoul

Medically reviewed by Dr. Chae-ho Lee, Medical Director, Doctorpetit Clinic Hongdae; Member, Korean Society of Clinical Aesthetic Medicine

Doctor profile · Doctorpetit Clinic Hongdae, Seoul

Masseter Botox in Seoul is a non-surgical jaw slimming treatment: botulinum toxin is injected into the masseter, the thick chewing muscle at the angle of the jaw, to temporarily reduce its activity and, over the following weeks, its bulk. When a wide or square lower face is caused mainly by that muscle, the result can be a softer, slimmer-looking jawline. At Doctorpetit Clinic Hongdae, every jaw botox plan starts with an assessment of whether muscle is really the cause.

What Is Masseter Botox?

Masseter Botox is a minimally invasive treatment in which botulinum toxin is placed into selected parts of the masseter muscles to temporarily reduce how hard they work, which gradually reduces their size and can narrow the lower face.

• Target: the masseter, a powerful muscle you can feel bulge at the back of the jaw when you clench your teeth.
• First effect: the muscle-relaxing action develops over the first several days.
• Second effect: with less work to do, the muscle slowly loses bulk, which is what produces the visible contour change over several weeks.
• What it does not change: the jawbone, facial fat, and loose skin are not reduced by this treatment.
• Individual dosing: injection points and the amount of botulinum toxin are set according to muscle size, facial anatomy, muscle activity, and goals.

A review of botulinum toxin for masseter hypertrophy describes the mechanism as interference with the nerve signal that produces a selective loss of muscle function and then a decrease in the muscle's mass (Comprehensive review, PMC). The same review notes that an enlarged masseter is not only a cosmetic matter: it can be linked with pain in the jaw region, fatigue, and discomfort while chewing.

It is worth knowing how this use is classified. A review in Aesthetic Surgery Journal Open Forum points out that lower-face botulinum toxin treatment, although widely performed in Asia, was, as of 2023, not officially approved for this indication in any country (ASJ Open Forum review). That makes the doctor's assessment and dose judgement especially important.

Non-surgical jaw reduction: what it can and cannot do

People searching for V-line or square jaw botox are often comparing it with surgical jaw reduction. The two work on different structures. Masseter Botox reduces soft-tissue bulk from muscle, so it can narrow the angle of the jaw in people whose width is muscular, and the change is gradual and temporary. It cannot reshape bone, so a wide jaw that is mostly skeletal will change little. The degree of visible contour change varies from person to person, even when the muscle is clearly enlarged.

Why international patients ask for it

Visitors to Korea commonly request Masseter Botox to reduce a bulky-looking lower face, create a softer jaw contour, or address prominent masseters associated with clenching. The minimally invasive approach and short appointment also suit a brief stay in Seoul.

Who Performs Masseter Botox at Doctorpetit Clinic Hongdae

Masseter Botox at the clinic is performed by Dr. Chae-ho Lee, Medical Director and the only physician at Doctorpetit Clinic Hongdae. Jaw and masseter Botox is listed among his subspecialty techniques, within Botox treatments, the first of his stated core specializations. Before leading the Hongdae clinic he was a director at Lienjang Clinic Hongdae and at Doctorpetit Clinic Gangnam. He examines the muscle while you clench, decides whether botulinum toxin is the right tool for your jaw, and performs the injections himself. His stated priority is a natural result that keeps your face recognisably yours.

Who Is a Good Candidate for Masseter Botox?

The best candidates are adults whose lower-face width is substantially influenced by prominent masseter muscles. Because a broad jaw can also come from bone, fat, or skin laxity, the consultation focuses first on identifying the cause.

You may be a good candidate if you:

• Have a square or wide-looking lower face that becomes more prominent when you clench.
• Can feel a firm, enlarged muscle at the angle of the jaw.
• Notice strong masseter activity associated with clenching.
• Want a softer jaw contour without surgery.
• Can wait several weeks for the slimming effect to develop.
• Understand that results last several months and may need maintenance.

Masseter Botox may be unsuitable, or may need postponing, if you:

• Have an infection or significant inflammation at the injection site.
• Have known hypersensitivity to botulinum toxin or its ingredients.
• Have certain neuromuscular disorders.
• Have swallowing difficulties.
• Have another medical condition that increases treatment risk.
• Are pregnant or breastfeeding, which should be discussed with the doctor.

When another approach fits better

If lower-face width comes mainly from bone structure, Masseter Botox may not deliver the change you want, and facial-contouring procedures are the relevant comparison. If fullness is from fat, treatments for facial fat may be considered. If the concern is sagging skin, skin-tightening procedures address that. If your main problem is teeth grinding or jaw clenching rather than appearance, a dental or medical evaluation may also be appropriate.

What to Expect: Procedure, Recovery, and Results Timeline

The consultation

Dr. Lee looks at your facial shape, the size and activity of each masseter, and how your jaw moves. He asks you to clench your teeth so he can feel and see the muscle contract. He reviews your medical history, medications, and any previous botulinum toxin treatment. The aim is to answer one question: is the width of your lower face mainly muscle? If one side is larger than the other, that is noted too.

The ASJ Open Forum review observes that both masseters are commonly injected with the same dose, but that people with different volumes on the left and right may need individualized dosing (ASJ Open Forum review).

Before treatment

Tell the doctor about your medications and supplements, allergies, medical conditions, earlier botulinum toxin treatments, swallowing difficulties, neuromuscular conditions, and pregnancy or breastfeeding. Mention any infection or inflammation near the jaw. Ask which medications or supplements might increase bruising, but keep taking prescribed medicine unless a doctor advises otherwise.

The procedure

1. Consultation and facial assessment.
2. Masseter activity is checked, including while clenching.
3. The treatment area is identified.
4. The skin is cleansed.
5. Injection sites are selected.
6. Botulinum toxin is injected into the targeted masseter muscles.
7. The injection sites are checked.
8. Aftercare instructions are given before you leave.

General anesthesia is not needed. The injections can cause brief discomfort, and ice cooling or another local comfort measure may be used according to the clinic's protocol. Masseter Botox is a short outpatient treatment and does not normally require an overnight stay; the exact time depends on your treatment plan.

Results timeline

Time after treatment	What usually happens
Same day	Most patients return to normal daily activities shortly afterward.
First several days	Muscle activity starts to decrease; temporary tenderness or bruising may appear.
Over several weeks	The muscle reduces in bulk and the jaw contour gradually slims.
Several months	Results commonly last for several months; maintenance may be considered after reassessment.

The slimming is gradual, so a mirror check a few days after the injections will not show the final shape. In a small randomized, triple-blinded trial in women with masseter hypertrophy, muscle thickness fell after one injection but partly recovered by six months, a second injection at three months produced a further reduction on one side, and the authors noted that multiple injections can cause functional adverse effects (Randomized trial, PMC). Repeat treatment timing is a clinical decision rather than a fixed schedule.

Three things mainly shape how much your jaw changes and how quickly: the starting size of the muscle, the treatment plan chosen for it, and your own response to botulinum toxin. Because the masseter is also the muscle you chew with, the dose is a balance between a visible slimming effect and keeping comfortable everyday function, which is one more reason the amount is set individually rather than copied from another patient.

Planning around a short trip

Because the slimming develops over weeks, most of the visible change will happen after you have returned home. Taking your own photographs from the front and at an angle before treatment makes it easier to judge the result later. Keep the clinic's contact details, including the website and phone line, so you can reach the team if something looks or feels wrong after you leave Korea.

Aftercare

Avoid rubbing, pressing, or massaging the jaw immediately after treatment. Follow the instructions you are given about strenuous activity and facial treatments. Contact the clinic if you develop significant facial weakness, difficulty swallowing, breathing problems, or other worrying symptoms. You can compare typical outcomes in the clinic's before-and-after gallery, keeping in mind that every face responds differently.

Combining Masseter Botox with Other Treatments

A wide or heavy lower face often has more than one cause. When fat or skin laxity also contributes, Masseter Botox may be combined with another treatment, with the combination and timing set after assessment.

• Fat Dissolving & Body Contouring — when localized fat, rather than muscle, adds fullness along the jaw.
• Non-Surgical Lifting — when loose skin or early jowling is part of the picture.
• Dermal Fillers — when contour definition depends on volume as well as width.

Safety, Precision, and Clinic Standards

• The Ministry of Health and Welfare registered Doctorpetit Clinic Hongdae as a foreign-patient-attracting medical institution in January 2023.
• Treatment targets the masseter muscles rather than the skin or jawbone.
• Injection points and dose are individualized to muscle size, anatomy, activity, and goals.
• Each patient is assessed one-on-one by the Medical Director before any injection.
• The clinic states that it uses genuine products at the indicated dosage.
• Aftercare information and contact details for questions are provided, with English support for international patients.

Risks to understand

Temporary pain, redness, swelling, tenderness, or bruising can occur at injection sites. Because the masseter is a chewing muscle, you may notice temporary chewing fatigue or weakness, especially with harder foods. If a nearby muscle is affected, facial asymmetry or a change in your smile can occur. Rarely, more serious botulinum toxin effects can occur. The U.S. prescribing information for botulinum toxin products warns that the effect can spread from the injection area and that difficulty swallowing or breathing needs immediate medical attention (FDA prescribing information via DailyMed). Tell the doctor beforehand if you already have any swallowing problem.

The Bottom Line

• Masseter Botox relaxes an enlarged chewing muscle so that it slowly shrinks, which can slim a square-looking jaw.
• It works only when muscle is the main cause; it does not reduce bone, fat, or loose skin.
• Muscle relaxation begins within days, but visible slimming builds over several weeks and lasts several months.
• Chewing fatigue with hard foods is a recognised temporary side effect.
• Jaw and masseter Botox is one of Dr. Chae-ho Lee's listed subspecialty techniques.

Frequently Asked Questions

Will Masseter Botox make my face slimmer right away?
No. The muscle begins to relax over the first several days, but the slimming comes from the muscle losing bulk, which takes several weeks. Judge the result after that period rather than in the first week.

How do I know if my wide jaw is muscle or bone?
Dr. Lee checks the masseter while you clench and assesses your facial structure. If the width is mainly bone or fat, he will explain why another approach may suit you better.

Will I have trouble eating after jaw botox?
Some patients notice temporary chewing fatigue or weakness, particularly with tough or hard foods. It is usually temporary, and softer foods can help in the meantime.

Can Masseter Botox help with teeth clenching?
It may reduce excessive muscle activity linked to clenching in selected patients. If grinding or jaw pain is your main concern, a dental or medical evaluation is also sensible.

How long do jaw slimming results last?
Results commonly last several months, with individual variation. Whether and when to repeat treatment is decided after reassessing the muscle.

Is Masseter Botox painful?
The injections can cause brief pinching or discomfort. General anesthesia is not used; ice cooling or another local comfort measure may be applied.

Can Masseter Botox change my smile?
It can, though this is uncommon. If botulinum toxin affects a muscle next to the masseter, the smile can look temporarily different or uneven. Careful placement of each injection is meant to reduce this risk.

Can I fly home soon after treatment?
Masseter Botox is a short outpatient procedure without an extended recovery, so a stay of around 1–2 days is often enough. Confirm timing with the doctor, and allow extra time if swelling or bruising develops.

Book a Consultation at Doctorpetit Clinic Hongdae

If a square jaw is your concern and you are weighing Masseter Botox in Seoul, a one-on-one consultation with Dr. Chae-ho Lee will establish whether muscle is the cause. English consultation and interpretation support is available. Hongik University Station Exit 1 opens almost onto the Wookdo Building (151 Yanghwa-ro, Mapo-gu), and the clinic is on its eighth floor. Book your consultation online or read patient reviews first.

Disclaimer

Treatment suitability, expected results, recovery time, risks, and potential side effects vary by individual. The information provided is for general informational purposes and does not replace an in-person medical consultation. Patients should discuss their medical history, treatment goals, and individual circumstances with a qualified medical professional before undergoing treatment.

Sources & Further Reading

• PMC — Botulinum Toxin for Masseter Muscle Hypertrophy: A Comprehensive Review
• ASJ Open Forum — Botulinum Toxin for Masseter Muscle Prominence in Asian Populations
• PMC — Botulinum Toxin and Masseter Hypertrophy: Randomized Triple-Blinded Trial
• FDA — BOTOX Cosmetic Prescribing Information (DailyMed)