Bruxism & Jaw Slimming
By treating the masseter muscles at the angle of the jaw with botulinum toxin type A (a prescription-only medicine), this treatment can do two things: reduce the forceful clenching and grinding associated with bruxism, and over time soften the appearance of a widened, square jaw for a gentler lower-face contour. It is a medical treatment aimed at muscle overactivity rather than a purely cosmetic one.
Individual assessment & treatment by a Prescribing Advanced Nurse Practitioner.
Botulinum toxin is a prescription-only medicine. Suitability is assessed individually at your consultation.
Areas this treatment can help with
- Jaw tension and clenching (bruxism)
- Morning headaches and facial fatigue from grinding
- A square or widened lower-face contour
- Tension in the masseter muscles
The treatment in plain terms
The masseter muscles can become over-developed through habitual clenching and grinding, which both drives bruxism symptoms and creates a square jawline. Relaxing these muscles with carefully placed doses reduces the clenching force and, over several weeks, allows the muscle to reduce in size, softening the contour. Effects typically last around four to six months.
The Science Behind Bruxism Treatments
The masseter is one of the strongest muscles in the face, responsible for closing the jaw. In people who habitually clench or grind — often without realising, particularly during sleep — these muscles work overtime. Over time, the repeated force causes the masseter to enlarge and become over-developed, which both drives the symptoms of bruxism (jaw tension, morning headaches and tooth wear) and creates a wider, squarer lower-face contour. Botulinum toxin type A is a prescription-only medicine that temporarily reduces the nerve signals telling the masseter to contract. With the muscle at rest, the clenching force falls — easing tension and helping protect the teeth from further grinding. Over several weeks the over-developed muscle gradually reduces in size, softening the jaw contour. The effect is temporary, typically lasting around three to six months, after which muscle activity gradually returns and treatment can be repeated.
What the treatment can help with
From consultation to review
Consultation & assessment
We examine your masseter muscles, talk through your grinding, jaw pain and dental wear, and confirm the treatment is right for you. If a dental cause seems likely, we'll suggest seeing your dentist first.
Tailored treatment
A few precise injections are placed into each masseter muscle using a fine needle. The appointment is quick and usually well tolerated, with no downtime.
Gradual improvement
Over the following weeks the muscles soften and the clenching force eases. You may notice less jaw tension and fewer morning headaches as the contour gently refines.
Review & repeat
A review is arranged at around four to six weeks to check your response and symmetry. Repeat treatment is typically planned every four to six months as the effect fades.
Getting ready & looking after your treatment
Masseter treatment is straightforward, but a little preparation helps it go smoothly. We'll talk through your grinding habits, dental history and symptoms at your consultation, and only arrange treatment if it's right for you.
- Mention any tooth wear, bite issues or a known dental cause — we may advise seeing your dentist first
- Tell us if you use a night guard or mouthguard, and keep using it as advised
- Let us know about teeth clenching, sleep apnoea or jaw pain, and when it's worst
- Share details of any medicines and supplements, particularly biotin
- On the day, arrive as normal — no fasting is needed
- After treatment, avoid touching or rubbing the injected area for the rest of the day
- Avoid strenuous exercise and lying flat for a few hours afterwards
- Keep your review appointment so we can assess your response
Is this treatment suitable for me?
Masseter treatment is suitable for adults troubled by jaw clenching, grinding or a widened lower-face contour, provided there's no underlying dental issue needing dental treatment first. It isn't suitable during pregnancy or breastfeeding, or with certain neuromuscular conditions. We'll assess your symptoms and medical history at consultation to make sure the treatment is right for you.
Frequently asked questions
Many people find reduced clenching and fewer grinding symptoms after treatment, but it's important to address any underlying dental cause too. We may suggest you see your dentist, particularly if you have tooth wear or a bite issue, as the injection relaxes the muscle but doesn't treat the dental problem.
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Ready to discuss your treatment?
Your clinician will assess your suitability, answer your questions, and only recommend treatment when it's right for you.