Masseter Botox: Jawline Slimming and TMJ Relief in One Treatment
Masseter Botox relaxes the thick chewing muscle at the corner of your jaw. That does two things at once: it eases TMJ pain, clenching, and teeth grinding, and — as the over-worked muscle gradually shrinks — it slims a square jaw into a softer, V-shaped contour. It's non-surgical, takes minutes, and at Neoderma it's done by licensed medical providers at $12.95 per unit.
Medically reviewed by Sal Nadkarni, DO · Last updated July 11, 2026
What is the masseter muscle — and why does it get bigger?
Place your fingers on the back corner of your jaw and clench: the muscle that pops up is your masseter, one of the strongest muscles in the body relative to its size and the main muscle you chew with. Like any muscle, it grows when it's overworked. Chronic clenching and grinding (bruxism) — often from stress, or happening in your sleep without you knowing — bulks the masseter up, widening the lower face and creating a square, heavy, or “angry” jawline. Genetics play a role too: some people are simply built with larger masseters.
How does Botox slim the jaw?
Botox is injected directly into the masseter, where it temporarily blocks the nerve signal that tells the muscle to contract with full force. With the constant clenching switched off, the muscle gradually shrinks from disuse — the same way any muscle you stop training will slim down. Over about 6–8 weeks the masseter thins, the width at the back of the jaw reduces, and the lower face tapers into a smoother, more oval or heart-shaped contour. Nothing is cut or removed; you're simply letting an over-developed muscle relax back to a softer size. You can still eat and chew normally — the treatment dials the muscle down, it doesn't switch it off.
The other half: TMJ, clenching, and headache relief
For many patients, the slimming is a bonus — they come in for the relief. An overactive masseter is a common driver of TMJ pain, jaw soreness, morning tightness, and tension headaches, and the grinding it causes wears down teeth, crowns, and veneers. By reducing how hard the muscle can clench, Botox takes the pressure off the jaw joint and your teeth. People often notice they wake up with less jaw tension and fewer headaches within a couple of weeks — well before the visible slimming has fully set in.
Real masseter Botox results
Real Neoderma patients. Individual results vary.
What to expect: timeline and how long it lasts
The treatment itself takes just a few minutes — a few small injections into each masseter, with no downtime; you can head right back to your day.
- Week 1–2: clenching and TMJ tension start to ease.
- Week 6–8: the muscle visibly thins as it atrophies from reduced use.
- Month 2–3: the fullest jawline slimming and contour.
- Month 4–6: results hold, then gently fade; many patients can space repeat treatments further apart over time as the muscle stays smaller.
How much does masseter Botox cost in Anaheim?
Botox at Neoderma is $12.95 per unit. The masseter is a large, powerful muscle, so it takes more units than a frown-line treatment — commonly in the range of 20–30 units per side, depending on how large and strong your masseters are and whether you're treating for slimming, TMJ, or both. Prefer a longer-lasting option? Daxxify can extend results toward six months. You'll always get a written estimate before treatment.
Financing available through Cherry and CareCredit — split your treatment into flexible monthly payments. Learn more →
Masseter Botox FAQ
How does masseter Botox slim the jawline?
The masseter is the thick chewing muscle at the back corner of your jaw. Repeated clenching and grinding make it bulk up like any exercised muscle, squaring off the lower face. Botox relaxes the masseter so it isn't constantly contracting; over the following weeks the muscle gradually shrinks from disuse (atrophy), and the jawline narrows into a softer, more tapered, V-shaped contour. It's a non-surgical way to slim a wide jaw.
Does masseter Botox help with TMJ, clenching, and teeth grinding?
Yes — for many people that's the main reason to do it. By quieting an overactive masseter, Botox reduces the force of clenching and grinding (bruxism), which can ease jaw tension, soreness, TMJ pain, and the tension headaches that come from a clenched jaw. It also protects your teeth and any dental work from grinding damage. The slimming effect is often a welcome bonus of the same treatment.
How long does masseter Botox take to work and how long does it last?
TMJ and clenching relief often begins within 1–2 weeks. The visible slimming is gradual — the muscle atrophies over roughly 6–8 weeks, with the fullest jawline contour usually around 2–3 months. Results typically last 4–6 months, and because the muscle stays smaller between sessions, many patients find they can space treatments further apart over time.
How much does masseter Botox cost in Anaheim?
Botox at Neoderma is $12.95 per unit. The masseter is a large, strong muscle, so it usually takes more units than a frown-line treatment — commonly around 20–30 units per side depending on muscle size and your goals. You'll get an exact per-treatment estimate at your consultation, and financing is available through Cherry and CareCredit.
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