I have bonding on my two front teeth. Can braces be put on to those teeth even though they are not the natural tooth? Will it take longer to shift into place? How much will braces generally cost? How much more is Invisalign than traditional braces? Also my teeth that have bonding are in need of replacement I have had them for probably a little over 8 years. When is it time to replace them with crowns, and how much does crowns usually cost?