Square Jaw: When Is It Surgery, When Is It Botulinum Toxin?
Toxin shrinks an overdeveloped chewing muscle; surgery reshapes the bone itself — the right tool depends on which one built your jawline.
A wide lower face can come from a prominent mandibular angle, a bulky masseter muscle, or both. Botulinum toxin temporarily shrinks the muscle over weeks and needs repeating every several months. Jaw-contouring surgery trims the bone once, permanently, with the recovery and risks of an operation.
Finding out which one you have
Clench your teeth and feel the jaw corner: a mass that hardens sharply points to muscle, while a wide outline that stays bony even at rest points to skeleton. Many jaws combine both in ratios that vary by individual, which is why X-ray assessment often precedes the decision.
Muscle-dominant jaws usually respond well to toxin alone, and trying it first is a low-commitment test. If the bone is the driver, repeated injections will disappoint — get a specialist consultation with imaging before choosing the operating room.
MediIndex articles are for general information only and are not medical advice, diagnosis, or advertising. Outcomes vary by individual — consult a board-certified specialist for personal decisions.