How jaw slimming works
Jaw BTX is a prescription injection into the masseter muscle. The toxin reduces how strongly the muscle contracts. With less work, the muscle gradually loses bulk, and the lower face may look narrower.
The change comes from the muscle only. If your width comes from bone, buccal fat or loose skin, this treatment will not address it. That is why the first step is a clench test and an examination. This guide is general information, not a personal recommendation.
What is jaw BTX?
Jaw BTX means treating the masseter with small injections on each side. It is the same category of medicine as other anti-wrinkle injections, used here for bulk, not lines. Our jaw slimming treatment page covers the procedure itself. If your concern is the whole lower face, the face slimming guide explains the other structures involved. Potency units are specific to each product's own assay, so units from different products cannot be compared.
How the treatment is planned
Jaw BTX Singapore: when it fits and when it does not
| What is found | Does BTX fit? | What else may help |
|---|---|---|
| Masseter enlargement on clench test | It may fit | Staged review |
| A wide face with clenching or night-time grinding | It may fit, after assessment | Dental care stays important |
| A square jaw angle from bone | No | Bone is not changed by any injectable |
| Fullness from buccal fat | No | Assessment, as this is a separate issue |
| Loose skin or jowls | No | Lifting options |
| A short chin | No | Chin filler may be assessed |
Who it may suit
Jaw BTX may suit you if a clench test confirms masseter enlargement. It may also suit a wide lower face linked to habitual clenching or night-time grinding, or a square jaw angle that is driven by muscle, not bone. You need to accept that change is gradual and varies between people. Firm food habits can also build up this muscle, so your daily habits are discussed. Women more often ask for a narrower jaw angle. Men more often ask for a defined jawline.
When more than one cause is present
Many lower faces have several contributors. Where this is so, enlarged muscle is usually addressed first. Descended tissue is then treated, so that filler is not used to disguise laxity. Chin and jawline filler come last, once the profile has been reassessed. Each step is reviewed before the next. Plans of this kind may be staged across visits, and they do not need to include every step.
What it cannot do
The toxin acts on muscle, so fat is untouched.
Skin laxity needs a different route.
Bone shape stays the same.
A V shape also depends on the chin, as our V shape page explains.
It does not cure grinding or replace dental care.
Who should avoid it or wait
Please wait.
Such as myasthenia gravis or Lambert-Eaton syndrome.
A known allergy to the toxin or any of its components.
Wait until the injection site has settled.
Those affecting nerve-to-muscle transmission, such as aminoglycoside antibiotics. Caution applies with bleeding tendency or blood thinners.
Difficulty swallowing or breathing is a reason to avoid it. Pain, clicking, locking or limited opening at the jaw joint needs assessment first.
Risks to know about
Common effects are tenderness, small marks or a bruise, and chewing that tires more quickly for a period. These are short-lived. Less common effects are an uneven smile from spread to a nearby muscle, paradoxical bulging of untreated fibres, and a hollow look below the cheekbone. Difficulty swallowing is rare and urgent, so please seek medical help straight away if it occurs. Published reports describe paradoxical bulging as the most common of these events.
Recovery and what to expect
This is a short in-clinic procedure. You may have small injection marks or a bruise afterwards, and ordinary activity can continue. On the first evening, avoid rubbing the jaw, lying face-down, heavy exercise and alcohol. Over the next days, chewing may tire more quickly. The muscle contracts less first, and any change in bulk develops over the following weeks. How long the effect lasts depends on muscle bulk, the product and amount, and whether clenching continues. A treated muscle can rebuild if clenching carries on, and no duration can be promised.
How fees are worked out
Fees are not published. They depend on the area, what the assessment finds, the product and amount judged from masseter bulk, whether another treatment is combined, and how the plan is staged. A written quote is given at consultation after examination. The consultation also decides whether treatment is advised at all.