Wounds of the lips and cheeks occur frequently in horses. The most common cause is external trauma or secondary to the use of inappropriate bits or restraint devices. Lip lacerations may be accompanied by mandibular or incisive bone fractures with or without dental fractures and tooth avulsions. These occur when a horse grasps objects with its mouth and then pulls back when startled. Lip lacerations without bone or teeth involvement can be sutured, usually with a good result. Healing is rapid because of the good blood supply to the head. Lacerations left to heal by second intention can result in orocutaneous fistula, which may require resection and primary wound closure. Rarely, skin grafts or mucosal flaps are required to manage orocutaneous fistula.
Last full review/revision December 2013 by Jan F. Hawkins, DVM, DACVS