Posted by an Equine Vet/Dentist. I NEVER would have thought anything like this could be possible without a bit. It really shows how important dental care is for your horse.
I copied and pasted everything below in case the link doesn't work.
| These are the sort of ulcerations that can be caused by riding in a bitless bridle ( hackemore ) with sharp teeth ! Just because you don't have a bit in the mouth does not mean the pressure from the bridle pressing the cheeks on to the teeth is not doing damage. |