Botox Injection Possible on 1 Side of Jaw?

It is possible to inject only one side of your jaw with Botox to achieve better symmetry. The risks remain the same for the treated area.

Botox can be injected into only one side without any problems.  The botox will work only where it is inejcted.

I will inject botox in an asymmetric fashion if a patient as an asymmetric face.  In this way, Botox can be used to make asymmetries more subtle.  

Asymmetries may be balanced by injecting one side only. Some patients who have had medical conditions creating significant differences from side to side can be balanced by treating only one side. Your more active side might be “waking” up quicker than the other side and you may need to get the other side treated soon, also. What you don’t want to have happen is for one side to work and the other not. Such an imbalance might create a malocclusion of the teeth or an improper bite which might cause TMJ (temporomandibular joint) pain which can be quite painful and annoying in the jaw.

Botox injections in the masseter can be very effective. However 5 to 10 units is way to low. You will need somewhere between 40 and 60 to make any difference. Please discuss this with your dermatologist and make sure he/she has experience with unconventional Botox injections. Good luck.

This is one suggested temporary treatment of masseteric hypertrophy. There are many potential risks for asymmetric injection including occlusal disturbances and possible TMJ complaints. However, the risk of this appears to be relatively low from reported studies.
Remember that if the problem is due to a bony condition, Botox will have no effect. Also the Botox must be repeated on a regular basis to maintain the result.

Dear Prettyprints
Facial asymmetry is common and altering the dose of BOTOX to account for muscle mass asymmetry is often done to account for such differences. The doses you are referring to sound about right.
It is best to undertreat these issues and have more placed 4 to 6 weeks later. Once it is clear what dose you need, at the next treatment the full dose can be given.
Dr. Steinsapir

I don't have any personal experience using BOTOX in this fashion. It's usually to give a more angular appearance to an Asian, round face.
It sounds like you've been treated several times, and this time you see a difference between the sides. I routinely do BOTOX dose adjustments on the face. If your dermatologist is skilled in masseter injection, you should ask about a dose adjustment for your appearance. It sounds ok to me.
Best regards.

Botox can be used to relax the masseter muscles.  If one side is stronger than the other, more Botox can be injected into the stronger side without any problem.

Even though injecting Botox into the masseters is an off label use of Botox, this treatment is very helpful in improving hypertrophy of the masseters.
Some patients do have one masseter larger than the other side and the amount of Botox can be different on each side depending on the hypertrophy.
The improvement however is teporary and the treatment will have to be repeated every 3-4 months.

I perform Botox injections to the masseter muscle to help reduce fullness in this region. If you notice that one muscle is larger than the other, it is reasonable to discuss more medication on this side with your dermatologist. Keep in mind that there is a safe limit to how much should be injected within a 3-4 month period, and your physician will not want to go over that amount. I would also wait until all of the previous medication has worn off prior to proceeding. To our knowledge, there is no risk of injecting in this region, although it is considered an "off-label" use by the FDA because they have not reviewed Botox for this indication. Good luck!