These are all excellent questions and you need to ask them of the orthodontist that will treat you. You might see your general dentist for a referral, and get an idea if in fact orthodontics is the correct treatment for you.
I do cconcur- I would advise seeing a dermatologist
I do not know why there are dentists that are still using the Sargenti method, I can only hope that the dental societies and the FDA are diligent in their efforts to ban the method.
I do not think it is serious but I think you should have him look at it.
I wouldn't be concerned at this point, at your next visit to her doctor have the doctor take a look.
It is difficult to give you an opinion without seeing it, I don't think it is serious but if it continues I would suggest you see an oral surgeon to get a definitive diagnosis.
One of the things you have to consider is a dry socket, but the fact that your dentist has seen you and has not mentioned it leads me to believe that is not the problem.I could only suggest that you see your dentist again.
I would consider seeing your dentist and have an x-ray taken.I am not sure why you are using the ambisol. Stop using it and see if the symptoms abate.
I would think that the odds are very high that allo these teeth would hurt you after having the root canal therapy.I would retreat the tooth that seems to be the most symptomatic.If the pain persists in the other teeth then you would have no choice but to do the others.
At times the spicules will work themselves out.If they remain they need to be removed to make it comfortable to wear a denture which I am assuming you will have made.