The masseter is the thick muscle at the angle of the jaw that you use to chew. When it becomes overdeveloped — through genetics, stress-related clenching, or night-time teeth grinding — it can widen the lower face and produce a square jawline, jaw aching, headaches and worn teeth.
Treating that muscle is one of the few non-surgical treatments that addresses both a cosmetic concern and a functional one at the same time.
Who it suits
You may be a good candidate if you:
- Notice your lower face widening, often in photographs
- Clench your jaw during the day or grind your teeth at night
- Wake with jaw aching, or get tension headaches at the temples
- Have been told by your dentist that you are wearing down your teeth
- Can feel the muscle bulging when you bite down
A dentist is often well placed to spot this, because the earliest sign is frequently tooth wear rather than facial shape.
How the treatment works
A small amount of product is injected into the masseter muscle on each side. It reduces the strength of the muscle's signal, so the muscle gradually relaxes and reduces in bulk. Nothing is removed and nothing is cut — the change comes from the muscle doing less work.
What results to expect, and when
This is a slow treatment, and it is important to set expectations correctly. Most people notice a change in clenching intensity within two to four weeks, but visible slimming takes longer — typically eight to twelve weeks, because the muscle has to reduce in size.
Results generally last between four and six months. With repeated treatments, many patients find the muscle bulk does not fully return, because the habit of clenching has reduced as well.
Will it affect my smile or chewing?
It can affect chewing for a while: in the weeks after treatment, your jaw may tire more easily with tough or chewy food; this is usually temporary. A change in your smile is rare. This is precisely why the injector's knowledge of facial anatomy matters: the masseter sits close to muscles that control your smile, and placement that is too high or too superficial can cause an unwanted change in expression. This is a treatment where seeing a medically qualified practitioner with dental or maxillofacial training is genuinely important. If your smile changes, or chewing or opening your mouth becomes difficult after treatment, phone Dr Vicky Bu on +44 7545 341600.
How it compares with a Nefertiti lift
A Nefertiti lift targets the platysma muscle in the neck to improve jawline definition, whereas masseter treatment reduces the width of the jaw itself. They address different structures and are sometimes combined.
Cost
At My Timeless, jaw slimming and teeth grinding treatment starts at £269 for the smaller dose and £499 for twice that dose. The right dose depends on the size of the muscle and whether the primary goal is cosmetic or functional.
See the full price list or read more about jaw slimming and teeth grinding treatment.
Related guides
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- Full treatment price list
- Book an online consultation with Dr Vicky Bu
This article is provided for general information only and is not a substitute for a face-to-face consultation. A qualified clinician will assess your suitability, medical history and treatment options before any treatment is recommended.
