Brite Smile I paid $4000 for Invisaligne and have been abandoned halfway thorugh treatment! Office closed, no explanation! Internet

Paid $4000 for Invisalign treatment to Brite Smile  and now half way through my treatment I find out they have closed their office without notifying any patients, my dentist has had to quit due to the fact that the company has not paid her in months and no one will talk to me about what I can do to either continue my treatment or refund my money?
So I'm out $4000, left to dispute it with my credit card company. Totally frustrated knowing that all the months I've spent working with my dentist to fix my teeth will now be lost and failed attempts to speak to anyone at the brite smile offices. 
Totally unprofessional company with no regaurd for their patients or paying customers. I've been totally abandoned and ripped off with not so much as a warning! Please do not do business with these people!!! I'm left all alone to try and resolve this! If anyone can advise me on what I can do to prosecute this company I would be very grateful!