How Effective Are Lingual Braces if Missing Brackets Are Not Replaced? (photo)

I would ask to speak with your orthodontist in private and express your concerns about the brackets that have fallen off as well as your time in treatment and seemingly "lack of progress".  Many times in orthodontics you have to look worse before you look better. This conversation with your orthodontist will help you better understand your treatment and make you feel much better.

Once a bracket comes off of a tooth (whether on the inside or the outside of the teeth), that tooth can no longer move with the rest of the arch. I instruct my patients to call the office immediately following the loss of a bracket. We do our best to get them in within 24-48 hours. The only exception to this guideline is in the case of the very back molar which may not need to be moved very much or are just hard to get to. I would discuss the urgency of this problem with your doctor. If you are not satisfied with his answers, look elsewhere. Your smile is too important for indifference!

I am a big user of lingual braces and just love them.  I am able to do almost anything conventional braces can do...invisibly.  But treatment with linguals can be challenging.  If you have the type called Incognito, a lot of the challenges are taken away.  But with other types challenges can certainly be overcome.  Brackets coming off can be a challenge.  If they are coming off and being lost, they are expensive to replace.  In general, we prefer to have all teeth bracketed so everything can work as a system.  At times it might be OK to leave one off if that particular tooth is in good alignment and you are near the end of your treatment.

I would certainly try to have a candid conversation with your doctor to see what the problem is.