This section discusses a use or indication that is not currently approved by the FDA for labeling or advertising.

Chapter 7. Chin

Chin Anatomy

Imbalance in the chin affects the entire middle and lower third of the face.

(Adapted with permission from Ipsen.)

The centerpiece of the lower third of the face, the chin is governed by the mentalis, shaded in yellow in the illustration, the most medial muscle of the perioral area. The blue oval represents the approximate appropriate injection zone area for neurotoxin treatment of the chin.

Contraction of the mentalis causes a "cobblestone" appearance of the skin and possible deepening of the mentolabial crease. Imbalance in the chin, the centerpiece of the lower third of the face, affects the entire middle and lower third of the face.

Patients rarely just ask for the treatment of the cobblestone pattern. More often they ask for rejuvenation of the lower face in which the relaxation of the mentalis muscle will add to patient satisfaction.

Chin Treatment Approach

(Adapted with permission from de Maio M, Rzany B. Botulinum Toxin in Aesthetic Medicine. Berlin, Springer-Verlag; 2007.)
Although the mentalis muscle lies deep, superficial injections work well.

Typical treatment of the chin is via 1 central or 2 lateral injections, about one half to 1 cm above the chin (blue ovals; red X represents an alternative injection point). Injections should be kept at least 1 cm from the lower lip. Practitioners should inject low and be conservative with dosing (6 TO 25 DYSPORT Units in total or 3 to 10 BOTOX Units in total).

Chin Case

Reducing chin dimpling or cobblestoning.

To reduce dimpling, the patient was injected at points indicated by the blue circles (10 DYSPORT Units each) and the red circle (5 DYSPORT Units). The total dose was 25 DYSPORT Units.

Chin Injection Demonstration

The total dose was 20 DYSPORT Units.

Chin Results

Treated patient is unable to flex her mentalis muscle.

The patient is shown alternating from rest to full expression 17 days after treatment of the chin (total dose, 25 DYSPORT Units). After treatment she is seen unable to flex her mentalis and cause a dimpled chin as she could before treatment.

In the video, the patient alternates from rest to full expression. Note that it is important to keep injections low and dosing conservative to minimize adverse events such as ecchymosis, hematoma, inability to lower lip, irregular lip movement, loss of mandibular dental show on smiling, oral competence issues. Practitioners are advised to get informed consent as chemodenervation of the chin musculature can affect ability to eat or speak.

Chin Treatment Summary

High doses or an injection to close to the corner of the mouth might lead to asymmetry as well as difficulties while eating and drinking, such as drooling. A trial approach works well with follow-up in 1 to 2 weeks to correct asymmetries.