What percentage of Invisalign cases require attachments/buttons, and reduction, interproximal or otherwise?

Hi johngsmith,Thank you for posting your question. 100% of cases require attachments.  Attachments help to direct forces to help move a tooth in the proper direction.  Not all cases need buttons and not all cases need IPR. It all depends on the situtation. Hope this helps! Good Luck!  

Very few cases can be done without use of any of the techniques you mention.I have been doing Invisalign for 13 yrs and haven't come across that case yet.Could some of the cases we do with attachments be done without?  Yes, but with great difficulty.

That is a great question and a concern for most patients.  I would say that almost 100% of cases require attachments and some crowding cases nearly 50-60% would require some interproximal reduction depending on many factors that enable us to open space for alignment.  Remember Invisalign is a tool which is used in many different ways the principles and philosophies of tooth movement lie in the mind and hands of the treating Doctor using his/her tools.  Good luck