Masseter Botox in Newport Beach
The jaw muscle is one of the strongest in the body. When it’s overdeveloped — from clenching, grinding, or simply genetics — it changes the shape of the face. A few precise injections can change it back.
Masseter Botox — also called jaw Botox or jaw slimming — uses botulinum toxin to relax the masseter muscle. The result is a softer, slimmer jawline and, for patients who grind or clench, meaningful relief from the tension and discomfort that comes with it.
At Plump Medical Spa in Newport Beach, Dr. Amir Mortazavi, MD performs every masseter injection personally. Before any treatment, he assesses jaw asymmetry, bite mechanics, and individual muscle bulk — because no two jaws are the same, and the dose and placement that work for one patient can produce an entirely different result on another.
Two reasons patients book this treatment: facial contouring — slimming a wide or square jaw for a softer, more oval face shape — and functional relief from bruxism, chronic jaw tension, and the headaches that come with it. At Plump, both are addressed with the same precision.
Who is a good candidate?
Jaw slimming
A wide or square jaw caused by an enlarged masseter muscle. Common in patients who clench chronically, but also occurs naturally. Neurotoxin gradually reduces the muscle bulk for a slimmer, more defined lower face over 4–6 weeks.
Bruxism relief
Teeth grinding and jaw clenching — often during sleep — that causes jaw pain, headaches, tooth wear, and facial tension. Masseter Botox reduces the force of muscle contraction, relieving pressure on the teeth and TMJ.
Many patients present with both concerns simultaneously — an overdeveloped jaw from years of grinding that has also changed the shape of their face. A single treatment addresses both.
Dr. Mortazavi’s assessment process
Masseter Botox is one of those treatments where the consultation matters as much as the injection itself. The masseter muscle varies significantly between patients — in size, depth, symmetry, and how it interacts with the surrounding anatomy. Injecting without assessing those variables produces inconsistent results.
Muscle bulk assessment
Dr. Mortazavi palpates the masseter at rest and during clenching to determine the actual size and depth of the muscle on each side. This informs dosing directly — a larger muscle requires more neurotoxin to achieve the same degree of relaxation.
Asymmetry evaluation
Most patients have some degree of left-right jaw asymmetry, often from dominant-side chewing or grinding habits. Recognizing this before treatment allows Dr. Mortazavi to use different doses on each side — correcting asymmetry rather than preserving it.
Bite and TMJ evaluation
For patients presenting with bruxism symptoms, Dr. Mortazavi evaluates bite mechanics and any signs of TMJ involvement. This helps distinguish masseter-driven symptoms from broader jaw joint issues and ensures the treatment approach is appropriate.
Injection planning
Based on the assessment, a dosing and placement plan is determined for each side individually. Injection points are mapped to the body of the masseter muscle, avoiding the parotid gland and neighboring structures.
What to expect
Treatment
Masseter Botox is administered with a fine needle directly into the masseter muscle on each side. The treatment takes approximately 15 minutes. Discomfort is minimal — most patients describe a brief pressure or pinch at each injection point. No downtime is required.
Timeline
For bruxism relief, many patients notice reduced jaw tension and grinding within 1–2 weeks. For aesthetic slimming, the full effect takes longer — the masseter muscle gradually atrophies over 4 to 6 weeks as it is used less forcefully, producing a progressively slimmer jawline. Final results are typically visible at 6 weeks.
Duration
Results typically last 4 to 6 months. With consistent treatment over time, some patients find the muscle reduces in bulk permanently and require less frequent maintenance. The aesthetic slimming effect tends to last slightly longer than the functional bruxism relief, as the muscle regains some strength before visual changes reverse.
Follow-up
A follow-up at 4 to 6 weeks allows Dr. Mortazavi to assess the degree of muscle reduction on each side and adjust dosing for future treatments. Asymmetry correction is a calibration process that often improves with each session.
Every masseter treatment at Plump begins with Dr. Mortazavi’s personal assessment of your jaw anatomy — muscle bulk, bite mechanics, and any asymmetry present before a single unit is injected. No nurses, no assistants. The same physician who evaluates you performs the treatment.
Frequently asked questions
Does masseter Botox change the shape of your face?
Yes — gradually and subtly. As the masseter muscle reduces in bulk over 4 to 6 weeks, the lower face appears slimmer and less square. The effect is most noticeable in patients with significantly enlarged masseters. For patients with naturally prominent bone structure rather than muscle bulk, the change will be more modest.
Will masseter Botox affect my ability to chew?
For most patients, chewing is unaffected. The masseter is a powerful muscle and the doses used for aesthetic and bruxism treatment reduce its force without eliminating function. Some patients notice mild jaw fatigue when chewing tough foods in the first few weeks — this resolves as the body adapts.
How is this different from getting masseter Botox at a med spa?
At most medical spas, masseter injections are performed by a nurse using a standardized dose. At Plump, Dr. Mortazavi assesses each patient’s jaw asymmetry, bite mechanics, and individual muscle bulk before determining dose and placement. The difference matters most for patients with significant asymmetry or those who have had inconsistent results elsewhere.
How long until I see results for jaw slimming?
The aesthetic slimming effect develops gradually as the masseter muscle atrophies from reduced use. Most patients begin to notice a change at 3 to 4 weeks, with the full result visible at 6 weeks. Bruxism relief — reduced grinding force and jaw tension — is typically noticed within 1 to 2 weeks.
Can masseter Botox help with TMJ pain?
Masseter Botox can reduce the muscle tension that contributes to TMJ-related jaw pain and headaches. It is not a treatment for TMJ joint disease itself — patients with significant joint involvement may need additional evaluation. Dr. Mortazavi assesses bite mechanics and TMJ symptoms at consultation to determine whether masseter Botox is an appropriate approach for your specific situation.
Is masseter Botox permanent?
No — results are temporary and require maintenance every 4 to 6 months. However, with consistent treatment over time, the masseter muscle may permanently reduce in bulk in some patients, requiring less frequent or lower-dose maintenance. This varies by individual.
My jaw is uneven — can Botox fix that?
Jaw asymmetry caused by uneven masseter muscle bulk on each side can be significantly improved with asymmetric dosing — injecting more on the larger side to bring both sides into balance. Dr. Mortazavi assesses left-right symmetry before every treatment and adjusts doses accordingly. This is one of the key reasons his assessment process differs from a standardized approach.
Schedule a consultation
Masseter Botox for jaw slimming and bruxism relief is available at Plump Medical Spa in Newport Beach, serving patients throughout Orange County and Southern California.
4667 MacArthur Blvd, Suite 310 — Newport Beach, CA 92660
(949) 568-7544 — info@plumpmedicalspa.com
Tuesday – Saturday, 10am – 6pm — By Appointment Only