I was offered invisalign for correction of an overbite and for alignment of lower incisors that required 4 buttons on the top and 1 button on the bottom as well as IPR of all 4 incisors on the top and 3 on the bottom. I would prefer not to shave the teeth and now have been offered Invisalign using the same button placement but no IPR. Can it achieve the same goal without IPR?