Jawline Slimming

Masseter reduction or jawline slimming for both treatment of teeth grinding and also for the cosmetic purpose of slimming the lower face. It is a simple and effective treatment involving the injection of wrinkle relaxers into the large masseter muscles of the jaw.

Suitable for

Jawline slimming, treatment of headaches, treatment of teeth grinding, facial sculpting


Practitioner dependent, pricing starts from $600. Please see FAQs below




Average of 6 months


15 to 30 minutes

Pregnancy Safe?


dr kate marking up a client for jawline slimming injections
The use of muscle relaxant injections (or anti-wrinkle injections) is not just reserved for the relaxation of lines of facial expression and wrinkles.

A popular procedure is the use of muscle relaxant injections to reduce the size of the masseter muscles of the jaw. This is a common and extremely effective treatment for teeth grinding, or bruxism.

Many people have hypertrophic masseter muscles, either as part of their normal anatomy; or these muscles may be enlarged by excessive teeth grinding or clenching, known as bruxism.

With overuse from habitual teeth grinding, the masseter muscles become larger and over developed. Over time this alters the shape of the lower face, creating a square jaw line.

jawline slimming before and after 1
People who suffer from bruxism often report daily headaches, TMJ pain, ear and facial pain, worn down teeth and dental problems.

They suffer from daily pain and discomfort which has previously only been treated with special splints and physiotherapy.

In addition, the overuse of the masseter muscles from chronic grinding results in hypertrophy of the muscles (enlargement of the muscle) which causes cosmetic deformities and an enlarged, square shape to the lower face which is often asymmetrical.

jawline slimming masseter reduction before and after 2
Masseter reduction or jawline slimming for both treatment of teeth grinding and also for the cosmetic purpose of slimming the lower face is a simple and effective procedure which is why it is so popular.

The procedure involves the injection of wrinkle relaxers into the large masseter muscles to create a slim and more feminine jawline. The procedure works by relaxing (not paralysing) the muscle resulting in a softer and smaller appearance of the masseters and eventual atrophy (or shrinkage) over time.

The treatment can transform your face completely; many people go from having a square and masculine jaw to a narrow and oval face in a matter of weeks.


What does the treatment involve?

A consultation with our doctors/nurses is essential prior to having any treatment. A treatment plan will be arranged to address individual concerns and desired aesthetic outcome.

Muscle relaxant injections (the same product used as anti-wrinkle injections) is injected into the masseters on each side of the face and spread out at multiple points within the muscle to produce jaw reduction results. The amount of wrinkle relaxer used does vary but in general much larger amounts are needed when compared with treatment of wrinkles.

Facial slimming and a jawline reduction effect is seen at any time between 2 to 8 weeks. Most patients report a symptomatic relief of their facial pain and headaches within 2 weeks.

Full aftercare instructions are provided following each appointment.

How long do results last?

Often a repeat treatment will need to be performed 4-8 weeks later to ensure the best results as often large doses of Muscle Relaxer are required. This is very much patient dependent and those with severe symptoms or very large muscles may need multiple treatments initially. Follow up with repeat treatments is generally performed every 6-12months.

Over time as the muscle atrophies less muscle relaxant is needed with longer periods between treatments. The results improve significantly over the first year of treatment. Often the vicious cycle of teeth grinding is broken after the first year of treatment and people find they no longer require high doses or ongoing treatments.

What happens after my treatment?

Following treatment with anti wrinkle injections (wrinkle relaxers) for jawline slimming normal activities can be resumed. There may be mild swelling and redness at the injection points and occasionally bruising. You will be provided with full aftercare instructions.

There are some general precautions that should be taken to reduce the risks of side effects and to obtain the best possible results.

These include:

  • Ice can be applied to reduce discomfort, swelling and bruising
  • Avoid any strenuous activity or head inducing activities for 12 hours
  • Do not apply makeup to the treated area for 12 hours.
  • Do not rub or massage the affected area for 24 hours.
  • Do not lie down flat for 4 hours post treatment, or do strenuous exercise for the first 24 hours.
  • Do not have any facial treatments such as laser or peels for 2 weeks post treatment.

The masseters are two bulky muscles on each side of the angle of your jaw. They serve as muscles of mastication, which means they help you chew. A common concern with treatment of these muscles with muscle relaxants is that the muscle will freeze and you won’t be able to chew your food.

Given the large size of the muscle and the use of other smaller muscles of mastication, chewing is not affected by this treatment, although some people may report feeling a bit ‘funny’ chewing tough foods like steak immediately following treatment.

What are the risks of treatment?

With any medical procedure there are always risks involved and your doctor/nurses will discuss all risks and contraindications prior to performing any procedure.

The procedure is highly effective, with minimal or no pain and minimal downtime. Minor side effects such as bruising and swelling to the injections points may be noted.

A less common side effect is over treatment of the masseter muscles resulting in problems with chewing. This is minimised by correct dosing and placement of the muscle relaxing injections. A rare side effect is an asymmetrical smile due to product diffusion to neighbouring muscles.

Muscle relaxant injections cannot be given in people with underlying neurological conditions such as Myasthena gravis and in pregnant or breastfeeding women.

What are the costs?

Average of 40 units of brand ONE, 100 units of brand TWO for baseline/initial treatment.

Full quote available following consultation, amount depends on individual concerns.