Bridles and bits should be custom designed or fitted in order to minimize the occurrence of oral ulcers, according to a group of Swedish researchers led by Ove Wattle, DVM, PhD, from the Department of Clinical Sciences at the Swedish University of Agricultural Science.

"Oral ulcers and abrasions on the lips, cheeks, and tongue of horses are very common and are primarily caused by trauma," Wattle said. "For example, nose bands pressing against the horse’s cheeks and badly fitting bits are both thought to be common causes of oral ulcers."

These ulcers appear to be well-tolerated by horses, but are thought to be uncomfortable and have the potential to cause significant oral pain