LIVO Treatments

Jawline Slimming

When a wider lower face is shaped by the masseter muscles

Jawline slimming with carefully placed masseter injections can soften a broad or square lower face when strong chewing muscles are a meaningful part of the contour. At LIVO, we first distinguish muscle from bone, fat, skin laxity, and natural facial proportions before designing the plan.

Natural portrait showing a balanced lower-face contour

Why the lower face may appear wider

The lower face is shaped by several structures working together:

The width and angle of the jawbone
The size and strength of the masseter muscles
Fat along the lower cheek, jawline, or beneath the chin
Skin and soft-tissue laxity
The length and projection of the chin
Overall facial proportions

These factors often overlap. Two clients may both describe their face as square, yet one may have prominent masseter muscles while the other has a wider bony jaw, lower-face fullness, or early jowling. Similar appearances can call for very different plans.

Bone, masseter muscle, fat, skin, and chin proportions contributing to lower-face width

What is masseter enlargement?

The masseter is a powerful chewing muscle located at the back of the lower cheek. It becomes firm and prominent when the teeth are clenched.

Some clients naturally have stronger masseters. Habitual clenching, grinding, gum chewing, and other repetitive use can also make the muscle more prominent. As it becomes thicker, the lower face may appear broader or more angular.

The muscle can sometimes be felt when the teeth are clenched, but a consultation gives a much clearer picture. We consider the face at rest, the contraction pattern, natural asymmetry, bite function, and the balance of the whole lower face.

Normal masseter muscle compared with enlarged masseter muscle

How masseter injections create a slimmer contour

When enlarged masseter muscles are the main contributor, small amounts of botulinum toxin type A can be placed into carefully selected points within the muscle.

The medicine gradually reduces excessive muscle activity. As the muscle becomes less active, its visible bulk softens over time, allowing the lower face to appear more refined.

Our aim is not to switch the masseter off completely. We use a measured dose to preserve everyday chewing while creating a softer, more balanced lower-face contour.

Injection depth, position, and dose are tailored to your muscle thickness, contraction pattern, natural asymmetry, facial shape, and previous response.

When jawline slimming may be worth considering

Jawline slimming may be worth assessing when:

The lower face looks broad or square and the masseters are visibly or palpably enlarged
The masseter becomes prominent during clenching
One side is stronger or larger than the other
A softer lower-face contour is desired without surgery
Previous masseter injections produced a balanced result

Teeth Grinding

Clenching or grinding may accompany strong masseter muscles. Tell us if you experience jaw tension or related symptoms so that we can understand the full picture and, where helpful, suggest dental evaluation alongside your aesthetic plan.

When another approach may be more helpful

Botulinum toxin refines muscle-driven width. If the lower face is shaped mainly by bone, fat, skin laxity, or chin proportions, another approach may create a more meaningful result.

A naturally wide mandible
Fat along the jawline or beneath the chin
Skin and soft-tissue laxity
A short or retrusive chin that makes the face appear proportionally wider
Very thin facial soft tissue or existing lower-face hollowing

If the face already has limited soft-tissue support, reducing the muscle too much may make hollowing or jowling more visible. At LIVO, the goal is proportion and softness—not the narrowest possible face.

A thoughtful assessment matters more than a standard dose

During consultation, we will examine your face at rest and while clenching. We may consider:

Masseter size, borders, strength, and contraction pattern
Jawbone and chin proportions
Jawline definition and jowl position
Facial fat distribution and skin support
Baseline asymmetry
Clenching, bruxism, pain, clicking, locking, or restricted opening
Previous botulinum toxin treatment and response
Medical history, medications, and neuromuscular symptoms

If muscle enlargement is not the main cause, we will explain the options that better fit your anatomy. Sometimes the most thoughtful recommendation is a different treatment—or no treatment at all.

What the appointment is like

After confirming the borders and contraction pattern of the masseter, your provider will place several small injections into each side. The appointment commonly takes about 15 to 20 minutes.

Most clients return to their usual day immediately. The muscle begins to relax before the face looks slimmer. Early change may be noticed after two to four weeks, with a more complete contour developing around eight to twelve weeks.

Injection → reduced muscle activity → gradual reduction in muscle bulk → refined lower-face contour

Preparing for your appointment

Before your visit, tell us about your current medicines and supplements, previous botulinum toxin treatments, allergies, and any relevant health or jaw history. This helps our provider tailor the treatment to you.

We may take standardized photographs at rest and while clenching so that we can understand your starting proportions and follow the change over time.

After your appointment: what to expect

Small red marks, mild swelling, tenderness, or bruising can occur and usually settle quickly. Avoid repeatedly pressing or massaging the area unless your provider asks you to do so, and follow the simple aftercare guidance we provide.

Some clients notice temporary fatigue when chewing very firm foods while the muscle adjusts. If anything feels unusual or persists, tell us so that our team can review it with you.

Frequently asked questions

When will my face look slimmer?

Muscle activity decreases before muscle size changes. Some clients notice a difference after two to four weeks,How long does the result last? The effect commonly lasts about three to six months, although the visible contour may remain refined for longer. Duration depends on muscle size, dose, chewing habits, metabolism, and previous treatment.

Will chewing become difficult?

Most clients continue to chew normally. A small number notice temporary fatigue with very firm or prolonged chewing while the muscle adjusts.

Can it change the width of my jawbone?

Jawline slimming refines width created by the masseter muscle. It does not change the underlying jawbone or directly reduce fat. If another structure is contributing, we will discuss options that may better support your goal.

Can it treat grinding or jaw tension?

Some clients notice less clenching or muscle tension after masseter injections. Because jaw tension can have more than one cause, tell us about your symptoms during consultation so that we can guide you appropriately.

Can it be combined with other services?

Book a jawline-slimming consultation at LIVO in Lisle, near Naperville and Oak Brook. We will assess your masseter muscles and the full lower-face structure before designing a plan that feels lighter, balanced, and still recognizably yours.

References

1. U.S. Food and Drug Administration. BOTOX® / BOTOX® Cosmetic Prescribing Information.

2. American Society of Plastic Surgeons. Botox to the Jawline—What You Need to Know.

3. Hong JY, et al. Efficacy and Safety of a Novel Botulinum Toxin A for Masseter Reduction: A Randomized, Double-Blind, Placebo-Controlled Study.

4. Yu CC, et al. Botulinum Toxin A for Lower Facial Contouring: A Prospective Study.

5. Kundu N, et al. Efficacy of Botulinum Toxin in Masseter Muscle Hypertrophy: A Systematic Review.

6. Peng HLP, et al. Complications of Botulinum Toxin Injection for Masseter Hypertrophy.

Begin with a consultation

Every LIVO plan begins with listening and a clear understanding of what you want to preserve.

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