Massetor / Teeth Grinding

Jawline slimming – or masseters reduction for cosmetic purposes – is a simple yet effective procedure that involves the injection of the neurotoxin botulinum type A into the large masseter muscles to create a slim and more feminine jawline.

The masseter muscles are the muscles that are attached at the angle of your jaw and control all the movements related to chewing food. For some people, strong jaw muscles are part of their normal anatomy. However, for others a square jaw line is the result of a condition called bruxism, which causes excessive teeth grinding or clenching.

With overuse from habitual teeth grinding, the masseter muscles become over developed and more pronounced, causing the shape of the lower face to alter and acquire that strong ‘square-jawed’ look (along with other painful and potentially more serious symptoms).

How Bruxism can affect the jawline

Clenching or grinding teeth is an involuntary movement, which we cannot control and can occur either while awake or asleep. The medical term for unconscious teeth grinding and jaw clenching is bruxism, and many people suffer of it for years without even realising it.

70% of grinding and clenching happens at night when we sleep, but it can also happen while we are concentrating (for example driving, reading, or watching TV) or under stress.

This causes a hypertrophic growth of the muscles attached to the jaw, called the masseters, and therefore a wider square-looking face.

In addition to the aesthetic reasons behind treating the masseter muscles, many people with bruxism also suffer from pain and discomfort which has previously only been treated with special splints and physiotherapy.

Summary Of Your Treatment

Procedure Time

30 Minutes estimated

Down Time

Usually None


Bruising, Redness, Asymmetry, Infection, Crooked Smile, Drooling

Duration Of Results

5+ Months

Jawline Slimming Treatments

Traditional treatments include anti-bruxism devices and medications, whereas recently neurotoxins such as Botulinum Toxin have been proven very helpful to provide relief from bruxism symptoms, including a square jawline.

Botulinum for bruxism treatment

Conventional treatments can help bruxism sufferers successfully protect their teeth from damage at night, however, they do not address the source of the problem.

Recently, a new procedure with the injectable neurotoxin Botulinum Type A, has proven to be an innovative treatment option for targeting and treating excessive muscle activity and spasticity.

Botulinum toxin can soften the appearance of the jawline, leading to dramatic changes in face shape after regular treatment. A slimmer jawline also results in more prominent cheekbones and chin, which are especially important for women, who typically want high cheekbones and a clean jawline.

Chin sculpting with filler can also enhance the jaw angle, which is why this treatment is often done in combination with the jawline slimming procedure.

How does the procedure work

Small doses of botulinum toxin are injected directly into the masseter muscles on each side of the face and spread out at multiple points within the muscles. This helps the muscles relax, reducing the grinding and the masseters hypertrophy.

Most patients report thinning of the face and jaw as a result of treatment with botulinum toxin, while voluntary movements, such as chewing and facial expressions, are not affected by the procedure.

The procedure is highly effective, with minimal or no pain and absolutely no downtime at all. Face slimming and jaw reduction effect is seen at any time between 2 to 8 weeks.


The jawline slimming treatment can transform your face completely. In fact, people can go from having a square and masculine jaw, to a narrow and oval face in a matter of weeks.

Depending on the treatment recommended, you could start to see the results within three weeks. Results typically lasts for 4/6 months . 

The results generally improve significantly over the first year of treatment. Finally, as the muscles relax and atrophy over time, less botulinum will be needed and there will be with longer periods between treatments.

Side effects and contraindications

Using botulinum toxin to relax the masseter muscles is a safe and effective way for treating both the neurogenic and muscular components of bruxism with little downtime and minimal side effects.

The injections are slightly prickly or stingy and take about 5 minutes to complete, after which you can return to your normal activities. Side effects relating to the spread of botulinum toxin far away from the injection site have been reported very rarely.

Treatment with botulinum toxin is not suitable for pregnant or breastfeeding women and is subject to previous consultation with Dr Nina.