Medically reviewed by Dr Ahmed Haq, Medical Director, Cosmedocs Harley StreetGMC 6078057Last reviewed
Square or wide jaw — softened, not surgically.
A wide jaw may reflect muscle, bone or soft tissue. We identify which is dominant before considering treatment. Selected muscle-related widening may respond to anti-wrinkle treatment; bony anatomy will not.
One concern. Several possible reasons.
The treatment depends on which one is yours.
Possible causes
Jaw width may reflect bone, muscle size, soft tissue or a combination. Clenching symptoms do not establish the cause on their own.
How we assess it
We examine the masseters at rest and during contraction and review clenching, pain, dental symptoms and facial balance.
Possible options
Selected muscle treatment, dental or pain assessment, monitoring or no intervention. Filler does not reduce jaw width.
Cosmetic + medical
Same treatment slims the jaw and resolves clenching, jaw pain, headaches and tooth grinding (bruxism).
5–10 day relief
Functional benefit (less clenching, better sleep) is the first thing patients notice — well before visible slimming.
Conservative first
We start at the low end of the dosing range. You can always add more; you cannot remove.
Your treatment options
Masseter Botox (Jaw Slimming)
25–50 units per side. Visible slimming at 3–8 weeks. Cosmetic primary intent.
See protocolBruxism (Clenching / Grinding)
Same injection, medical primary intent. For tooth chipping, jaw pain and tension headaches.
See protocolHow many units do I need?
Doctor-written dosing guide — 25 vs 50 vs 75 units, what to expect at each.
Read guideJawline Definition (rare combination)
Where the angle is wide but the front of the jaw lacks projection — masseter relaxation plus chin/jawline filler.
See protocolCommon questions
Why is my jaw wide or square?+
Jaw width can reflect muscle size, bony anatomy and soft tissue. Assessment distinguishes these before discussing whether muscle treatment is suitable.
How many units of masseter botox slim the jaw?+
Typical doses are 25–50 units per side depending on muscle bulk and goal. We always start conservatively — you can add more at week 2; you cannot remove it.
When will I see slimming?+
Functional relief (less clenching) is reported within 5–10 days. Visible slimming begins at week 3 and peaks at week 8–12. Maintenance is typically every 4–6 months.
Will it change how my face looks from the front?+
Yes — that's the goal. Most patients describe a softer, more 'V-shape' lower face, with a less hard outline at the angle of the jaw.