Sharp points: The most common tooth problem in a horse's mouth
Two facts are responsible for the most common, re-occurring dental problem in the horse's mouth: Horse teeth never stop growing and the upper molars are wider than the lower ones. Over time, this creates sharp points on the edges. When pressure through bitting and/or tight nose bands is applied, the cheek is pushed into these sharp points causing uncomfortable bruising and lacerations to the cheeks.
These sharp points should be routinely adjusted as part of regular equine dental maintenance, as well as the carefully setting up of the absolute correct geometry for each individual horse by a certified professional equine dentist.
Video (courtesy of doctorhorse.it): Treatment of sharp points on the molars.