Shoes will not necessarily make this problem better.  For cracks of any kind, I usually bevel more so that the forces on the hoof wall are directed inward to help hold the hoof together.  Pete has tried both beveling more, and he has also removed a section to take all pressure off the wall.  You might also try soaking in a lysol/water solution or use Pete's "goo" a 50/50 mixture of athlete's foot cream and triple antibiotic cream.  My friend found that this helped a lot with a crack that had developed at the toe of her mare.  Daily soakings really helped resolve it as evidently there was bacteria and fungus getting into the crack and further weakening the wall.  You say this is a quarter crack, but you say it's at the front toe.  If it's at the toe, it's not a quarter crack...they are located...at the quarters :)  This is just a toe crack.  You might also make sure that the heel is where it should be.  Often the toe cracks because the horse is hitting there first instead of the heel.

 

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