Arrugas y expresión
Volumen y contorno
Diagnóstico
Tratamientos médicos
Micropigmentación capilar
Regeneración y volumen
Otros tratamientos
Medicina estética íntima
Cirugía menor
Wrinkles and expression
Volume and contour
Diagnosis
Medical treatments
Scalp micropigmentation
Aesthetic
Regeneration and volume
Other treatments
Intimate aesthetic medicine
Minor surgery
— Facial treatment · Barcelona
Dr. Bermejo Pérez · Reg. no. 63226
Botulinum toxin in the masseter muscle for teeth grinding, jaw tension and a slimmer jawline. A treatment with a double purpose — functional and aesthetic — that calls for precise anatomical judgement.
In short
Masseter injections relax the muscle that clenches the jaw: they ease bruxism (teeth grinding) and slim the lower face. A session takes 20–30 minutes with no downtime, and the effect lasts 4–6 months. Price: €350–550, both sides. Treatment is performed by Dr. Rubén Bermejo Pérez, a registered aesthetic physician (COMB no. 63226), at Clínica Sagrada Família, Barcelona.
Dr. Bermejo explains the double role of masseter injections: relaxing the muscle if you clench your teeth, and slimming the jawline.
Medical judgement
“The masseter isn't treated the same way in everyone. Dose, depth and entry point change with your anatomy — and with whether the goal is functional, aesthetic, or both.”Dr. Rubén Bermejo Pérez
Anatomy · Masseter injections
A powerful muscle, a softer line.
The muscle that clenches the jaw. When it overworks, it grows and widens the lower face.
Relaxing it reduces the force with which you clench your teeth.
Over time the muscle loses bulk and the contour becomes slimmer.
It is applied at a few points on the muscle, located by touch.
What it treats
Bruxism is the involuntary clenching of the teeth, especially during sleep. Over time it enlarges the masseter and causes jaw and neck pain and headaches. Botulinum toxin relaxes the muscle gradually — most patients notice a clear improvement from the second week.
An enlarged masseter gives the face a square, heavier look. Toxin in the muscle reduces it gradually over 4–6 weeks, slimming the lower face without surgery. In women it is one of the treatments with the biggest visual impact. In men it needs more judgement so as not to feminise the result.
Chronic masseter tension causes pain that spreads to the neck, temple and behind the eye. In many patients botulinum toxin has a marked pain-relieving effect — one of the uses where the functional result outweighs the aesthetic one.
Many people with bruxism end up wearing down their tooth enamel irreversibly. Treating the masseter reduces clenching force and protects the teeth. It is common to coordinate with your dentist when wear is already present.
No filters
Its main effect doesn't show in a photo: you feel it when you wake up. This is how bruxism treatment with toxin evolves.
Days 3–7
The muscle starts to relax. You won't notice anything odd when eating or talking.
2–4 weeks
Less jaw pain and fewer morning headaches, and less force when clenching at night.
2–3 months
In some people, as the muscle reduces, the angle of the jaw looks slightly slimmer. It isn't always visible, and it isn't the main goal.
Duration
It is repeated when the tension returns. With regular sessions, the effect tends to last longer.
What it doesn't do: it doesn't replace a night guard or your dentist's follow-up: it complements them by reducing muscle force and tension.
The practical side
Everything you need to know before your consultation. No small print.
The masseter is a large muscle — the effect tends to last slightly longer than in the upper face. With regular sessions it lasts longer.
Including palpation, assessment and marking on both sides. No recovery time afterwards.
Possible mild discomfort at the injection site for the first few hours. Normal life straight away.
Both sides. The price depends on the units needed. An assessment beforehand is advised to set the exact dose according to muscle size.
Who it's for
Not sure if it's for you? That is exactly what the consultation is for: I'll tell you honestly what I see.
Free first visit · no commitment
In the consultation we look at the proportions of your face, talk about what you want and set the goals together. If you don't need treatment, I'll tell you that too.
Frequently asked questions
Straight answers about masseter injections. If your question isn't here, write to me.
The guide price is €350–550, both sides. The price depends on the units needed; an assessment beforehand sets the exact dose according to muscle size. The first consultation is free. You can see all fees on the prices page.
Yes, when a wide jaw is due to enlarged masseters, which is common in people who clench or grind their teeth. As the muscle relaxes, it loses bulk and the lower face looks slimmer. It isn't immediate: it starts to show at around 4–6 weeks and peaks at 2–3 months. If the width is due to bone or fat, toxin won't correct it and I'll suggest another option. For forehead lines, frown lines or crow's feet, see anti-wrinkle injections.
At Clínica Sagrada Família, C/ Torras i Pujalt 1 (3rd floor), Barcelona. It is performed personally by Dr. Rubén Bermejo Pérez, registered physician no. 63226.
Discomfort is mild. The masseter is a large, easy-to-reach muscle — the injection is quick and well tolerated, with no anaesthetic needed. Some patients feel slight pressure when chewing for the first few days, which goes away on its own.
Results in the masseter are slower than in the upper face. Relief from bruxism is felt within 1–2 weeks. The reduction in muscle bulk and the slimmer jawline appear gradually between 4 and 6 weeks.
No. The change is gradual — people perceive a more rested look or a slimmer jawline without being able to tell why. It is one of the most discreet results in aesthetic medicine.
Not significantly. The masseter has plenty of functional reserve — even with reduced strength, normal chewing isn't affected. Some patients notice a slight difference when biting very hard foods for the first few weeks, which goes away on its own.
Between 4 and 6 months. With regular sessions the muscle tends to reduce more permanently and the effect lasts longer. Many bruxism patients gradually space out their sessions.
Yes, and they are often combined. A night guard protects the enamel but doesn't reduce clenching force — the toxin does. In severe bruxism, both treatments complement each other.
Avoid massaging the area and very hard foods for the first 24 hours. There is no downtime — normal life straight away.
Free consultation
First visit with no commitment. There is always an assessment first; if the treatment is right for you, it can be done the same day.
In Sant Gervasi, next to Ronda del General Mitre. It is not in the area around the Sagrada Família basilica.