Chin Lipo Complications. Will my speech and smile be permanently altered for life?

It is a fact that Liposuction of the Chin/ Neck can "bruise" the branch of the nerve that lowers the lip when you smile.  In my experience this always recovers on its own.  Having said that, you should see your surgeon again to discuss in detail, or seen an opinion from another board certified plastic surgeon.  Best of luck. Dr. Romanelli 

Three weeks seems like a lifetime while recovering but your body most likely needs time to recover. I find that time and exercising the affected muscle(s) helps them to respond a bit quicker by frowning, puckering your lips, smiling, etc. Swelling and bruising on or around the nerve may have blocked the connection to the facial muscles that you are trying to use. The hardness from liposuction is swelling. Manual massaging can help that fluid drain quicker.

Hi and welcome to our forum! Neuropraxia is the mildest form of nerve injury resulting in a temporary block of motor or sensory function. It is usually due to swelling or bruising of a peripheral nerve. Recovery may take days or up to 3 months. There should be no permanency. Surgery takes time to heal!
Best wishes...