Last updated May 2023

What is jawline slimming?

Hypertrophy (increased size) of the masseter muscle can be treated with anti-wrinkle or muscle relaxing injections. This is often sought out by those wanting to achieve facial slimming or jawline slimming. Slimming the jawline can help to convert a square-shaped face into an ‘upside down triangle’ shape.

Jawline and facial slimming using anti-wrinkle injections involve targeting specific facial muscles, such as the masseter muscles. Relaxing the masseter muscles result in an overall reduction in facial width and fullness of the lower face and jawline.

Anti-wrinkle injections are an effective, nonsurgical option for reducing the width and shape of the lower face and jawline.

How does jawline slimming treatment work?

Jawline and facial slimming with anti-wrinkle injections typically involve using neuromodulators like anti-wrinkle injections. The treatment works by injecting anti-wrinkle injections into specific muscles, such as the masseter muscles in the jaw area.

When the anti-wrinkle injection is injected into the masseter muscles, it temporarily blocks the nerve signals that cause the muscles to contract and become bulky. This relaxation of the muscles reduces their size over time, resulting in a slimmer and more defined jawline.

In addition to reducing the size of the masseter muscles, anti-wrinkle injections can also help with bruxism, a condition characterised by teeth grinding and jaw clenching. By relaxing the muscles responsible for these actions, the injections alleviate muscle hyperactivity and minimise the associated tension, relieving the symptoms of bruxism.

The effects of anti-wrinkle injections for jawline and facial slimming are not immediate and typically become noticeable within a few weeks. The treatment is temporary and may need to be repeated every few months to maintain the desired results.

What is bruxism?

Bruxism is a condition characterised by teeth grinding and excessive jaw clenching. It usually occurs at night during sleep and can have consequences such as the blunting of teeth, headaches, temporomandibular joint (TMJ) problems, and an increase in the size of the masseter (chewing) muscles that result in a widening of the jawline and a square appearance of the face. A square jaw can be due to bruxism, or in some cases, it can be a genetic trait.

How can I slim my jawline non-surgically?

By injecting anti-wrinkle injections or muscle relaxants into the main jaw muscles that cause the bulk (the masseter muscles), the squareness of the jaw can be reduced significantly. The symptoms of bruxism will also be reduced. The procedure has virtually no downtime; it starts to work in 1 week and lasts about 4 to 8 months.

Usually, 20-50 units of anti-wrinkle injections are required in this area per side (40 to 100 units). The result is generally aesthetically pleasing for those with hypertrophy or enlargement of the masseter muscle. Furthermore, there is often a significant symptomatic relief of jaw pain, headaches, clenching and jaw tension.

The temporalis muscle, which is felt over the temples when clenching the jaw, is another target for anti-wrinkle or muscle-relaxing injections. The temporalis muscle works with the masseter muscles to help with chewing and to close the jaw. Although treatment of the temporalis muscle is less commonly sought for cosmetic purposes, muscle relaxing injections can help reduce headaches caused by excess tension in this muscle.

Another option for jawline slimming in some cases is to have liposuction over the parts of the lower face and jawline. This is only suitable for those with excess fat (and not muscle) in these areas. For more information on liposuction, click here.


Benefits of anti-wrinkle injections for jawline slimming

Jawline slimming injections in the masseter muscle can result in these benefits:

Jawline slimming side effects and risks

Immediately following your treatment, you may experience some temporary side effects common with anti-wrinkle injections, such as:

  • Mild discomfort or swelling
  • Bruising
  • Redness at injection points
  • Headaches

Once the treatment has taken effect, you may notice:

Who is unsuitable for jawline slimming treatment?

Anyone who is pregnant or breastfeeding should not undergo jawline slimming treatments. If you have any significant allergies, muscular disorders or severe scarring, you may not be suitable for jawline slimming treatment using anti-wrinkle injections. All patients must have a consultation before any treatment to discuss their suitability for treatment.

What happens during jawline slimming treatment

Before jawline slimming treatment

Prior to the procedure, you will have a consultation with a doctor who will discuss your goals and concerns and examine your face, jaw and chin to determine your suitability for treatment. If you’re suitable for treatment, a quote will be provided.

During jawline slimming treatment

The doctor will clean the treatment area on your face and use an ultrasound or accuvein device to find and map out any facial veins. They will then mark out the treatment area on your face and masseter muscle. Using a needle, the anti-wrinkle injection is administered into your masseter muscles.

The procedure will take approximately 15 minutes.

After jawline slimming treatment

You can return to normal activities following your procedure. However, you should avoid exercising or putting any pressure on the injection site for 24 hours afterwards. Results from this treatment are not immediate. You may start to notice some effect in 1 to 2 weeks, however, results will be noticeable 3 weeks following treatment.

Before and After Jawline Slimming

Case Study 1

This patient presented to the Victorian Cosmetic Institute with concerns about the squareness and wideness of her face.

Although she did not mention any teeth grinding problems, she had a very strong jaw (masseter) muscle. 45 units of muscle relaxant (anti-wrinkle injection) were injected into each side, and the result seen in the after photo was taken 3 months later at a follow up appointment. There was a dramatic reduction of volume in the jawline in this case. The result lasted 6 months.

jawline slimming melbourne masseters

Case Study 2

This patient presented to the Victorian Cosmetic Institute, wanting to treat her square jawline. The result below was achieved by injecting anti-wrinkle injections into the muscles that are responsible for chewing (along the jawline, adjacent to the ears – you can feel these muscles on yourself when you clench your jaw).

She was injected with 25 units of muscle relaxant (anti-wrinkle injection) to her right side and 35 units to her left side. The post photo was taken 3 weeks after the bruxism treatment, and a noticeable slimming of the jawline/face is apparent.

facial slimming botox melbourne

Case Study 3

This patient presented to the Victorian Cosmetic Institute for jawline slimming. She had anti-wrinkle injections to each of her masseter muscles on the sides of her jaw. Using anti-wrinkle treatments relaxes the muscles, reducing volume in the jawline. This image has not been photoshopped, and there was no surgery performed, only anti-wrinkle injections used in the jawline.

jawline slimming with botox before and after

Case Study 4

This patient presented with clenching and jaw tension problems, and had muscle relaxant treatment for her masseter muscle. The after photo on the right shows her result approximately 2 months after.

masseter botox jawline slimming melbourne


How much does jawline slimming cost?

In your consultation, the doctor will discuss the cost of your treatment with you as the price for facial slimming injections is normally determined per unit of injection. The factors that determine dosage include the muscle strength of your jawline and your desired outcome.

For our current price list click here.

How many units of anti-wrinkle injections do you need for masseter muscles?

Usually, 40-50 units are required in this area per side (total of 80 to 100 units), but this may vary on a case-by-case basis.

What are the masseters?

The masseter muscles are the main jaw muscles in the lower face, used for chewing, opening, and closing your mouth. Larger masseters can be caused by teeth clenching and jaw grinding, or they can be due to genetics. If you place your fingers on the outside of the back of your jaw and clench your teeth, you will feel your masseter muscles contract as you clench.

How long does it take to see results?

Some people report being able to notice results after 1 to 2 weeks, however, results are typically seen from 3 weeks onwards.

How long does jawline slimming last?

The duration of the results can vary between patients. You will need to have the treatments consistently in order to maintain the results of this treatment and we recommend retreatment anywhere between 4 to 8 months.

Why choose the Victorian Cosmetic Institute?

Since 2005, the Cosmetic Doctors and Nurses at Victorian Cosmetic Institute have performed many non-surgical treatments such as jawline slimming. Providing a thorough consultation process, our Doctors and Nurses can evaluate your suitability for treatment, taking into account your medical history, treatment goals and expectations.

To arrange your consultation at one of our Melbourne clinics, you can contact our Customer Care team directly at 1300 863 824 or book online.