What is the best way to fix an 11mm overbite?

There are no photos but you are describing an orthopedic issue which cannot be completly corrcted with moving teeth.I assume you have a narrow maxilla, "V" shaped Three Dimensional Growth with the DNA Appliance can turn this into a full wide "U" shaped arch allowing room for mandibular expansion.Do you have Headaches, TMJ disorders, Snoring or Sleep Apnea?

Instead of asking which appliance will decrease your overbite, a better question could be: how do they plan to achieve said 50% reduction in overjet? What is the mechanism, which teeth are moving where, will IPR be done, or are we expanding and proclining? And then the next question becomes: what is the most appropriate approach in your case? Is it OK to retract the front teeth, or do we need to look at promoting a more more forward position of the lower teeth and jaw? What does the airway look like, do you snore, have sleep apnea, grind your teeth? Orthodontic treatment tends to be more about the treatment goals, the details of the plan, not as much about what orthodontic appliance is going to be used.There are many ways to move teeth: modern high tech options like Invisalign, classic metal or clear braces, and various old school removable appliances constructed with acrylic and/or soldered wires that have been around for decades. It all begins with a thorough in-person evaluation to look at the underlying causes of your overbite, followed by a review of treatment options to address your concerns, while recognizing limitations to achieving absolute perfection. It sounds like you could benefit from a second opinion. Check out the Invisalign website to look for a provider. Rankings are based on number of patients treated. Most offices will provide a second opinion free of charge.