Cannot pull down lower lip after chin lipo, could this become permanent?

The nerve that supplies motor function to your lip runs in a plane that is located below the area of liposuction. Due to swelling and tumescent anesthesia, patients can experience temporary paralysis of this nerve. It is very uncommon for it to occur bilaterally. Laser liposuction produces heat to this area and can also injure the nerve at a deeper plane. Be sure to follow-up with your surgeon.

It's difficult to predict if this is permanent, but for most people this is temporary. I recommend following up with your surgeon about your concerns. Hope this helps. 

Thanks for your question.  The marginal mandibular nerve lies right underneath the mandible in most people, and can possibly be injured during submental (chin) liposuction procedures. This is the nerve that pulls a lip down and helps you frown.  If you can and cannot do this on both sides then you may have a nerve injury on both sides, which in my opinion is a better problem to have than a nerve injury on only one side, which causes a very asymmetrical smile and frown. If you are a only a day after your procedure, the nerves may still be affected by the numbing solution used for your surgery, especially if it is a longer lasting medication.  The heat generated from laser liposuction could potentially increase the chance of nerve injury, or the severity of the injury. These injuries are usually temporary, and the nerve function returns over time.  How far out are you from your procedure? If you have not seen your surgeon in followup yet make sure you get in soon. Best of luck to you!