Syspath: Alimentary

• Collagen arises from the collagen-producing cells (fibroblasts) of the oral cavity.
• The oral cavity prevents many harmful xenobiotic substances through "mouth feel" and taste.
• The oral cavity contains normal flora which can be killed by antibiotics and high blood glucose concentration.
• Thrush is a gross lesion characterized by a yellow-beige pseudo membrane of hyphae of candida on the dorsal surface of the tongue.
• Thrush is a microscopic lesion characterized by hyphae of Candida albicans growing in the superficial keratin of the tongue.
• Saliva functions as an electrolyte, antibacterial compound, antibody, wound repair enzyme, digestive enzyme, antimicrobial enzyme, and analgesic.
• Enamel is the only substance in the body incapable of turnover and repair.
• Acid etching of enamel from vomition of gastric acid or eating and drinking of acidic substances such as carbonated beverages produces permanent loss of enamel.
• Tonsils do not act as a lymphoid filter for oral structures, causing them to lack afferent lymphatic vessels.
• Initial multiplication of some enteric viruses occurs within tonsillar tissues.
• Neoplasms can occur in the epithelium (squamous cell carcinomas) and lymphoid tissue (lymphomas).
• Injury of salivary glands is accompanied by incomplete regeneration, principally from ductular epithelium, atrophy, fibrosis, and squamous metaplasia of secretory epithelium, sometimes resulting in blockage of ducts.
• Sialoceles are saliva-filled cysts.
• Ranula is a sialocele of the sublingual salivary gland.
• Portals of entry into the oral cavity include mechanical penetration of oral mucosa and pathogens having the opportunity to spread through submucosal tissues and enter vascular channels or draining lymphatic vessels.
• Vesicular stomatitides are caused by epitheliotropic viruses and are characterized by oral vesicles and blisters.
• Papular stomatitides are caused by parapoxviruses and are characterized by pathogenesis.
• Epitheliogenesis imperfecta is the incomplete development of the stratified squamous epithelium of skin, adnexa, and oral mucosa.
• Uremic stomatitis is characterized by caustic injury due to increased urea in blood and saliva, and thrombosis due to high blood urea nitrogen.
• Palatoschisis is associated with toxic plants in cattle, sheep, and pigs.
• Genetic factors contribute to palatoschisis in dogs, along with arthrogyposis, a congenital joint contracture in 2 or more areas of the body.
• Erosive and ulcerative stomatitides are characterized by epithelial necrosis and inflammation without vesiculation.
• Lymphoplasmacyttic stomatitis is characterized by red, inflamed gums, fetid breath, and inappetence, with hyperplastic and ulcerated oral mucosa and lymphocytes and plasma cells in the submucosa beneath the epithelium.
• Malignant catarrhal fever is caused by a herpesvirus and is characterized by fever, oral and nasal erosions, enlarged lymph nodes, and centripetal corneal opacity.
• Stomatitis is characterized by macules, papules, vesicles, erosions, ulcers, and necrosis with pseudomembranes.
• Steroid administration can cause palatoschisis in primates.
• Failure of fusion of the upper lip along the midline or philtrum is known as cleft lip or hare lip, or cheiloschisis.
• Palatoschisis is a failure of fusion of the lateral palatine processes of the maxillary bone that occurs during the first trimester of pregnancy and is attributed to genetic abnormalities, excessive intake of vitamin A during gestation, and the administration of cortisone during gestation.
• Epithelial surfaces are portals of entry for Bovine viral diarrhea virus (BVDV), a pestivirus in the Flaviviridae family, and Parvoviruses of carnivores.
• Bovine viral diarrhea (BVD) and mucosal disease are caused by Bovine viral diarrhea virus (BVDV), a pestivirus in the Flaviviridae family.
• Tonsillitis can be primary or direct infection, hematogenous infection, or primary neoplasm.
• Necrotizing tonsillitis in a dog is characterized by enlarged and discolored palatine tonsils, a whitish-gray diphtheritic membrane covering the right tonsil, and the left tonsil is extensively ulcerated.
• Lymphoma occurring in the tonsil is characterized by a white plaque on the tonsil.
• Gingival hyperplasia is a simple overgrowth of gum tissue, principally the fibrous submucosa, and is very common in adult brachycephalic dogs.
• Acute necrotizing ulcerative gingivitis is caused by anaerobic spirochetes, such as Fusobacterium and Borrelia vincentii.
• Tonsillar squamous cell carcinomas are more common in canids.
• Necrotizing stomatitides are secondary to erosions/ulcers and trauma, and can be caused by calf diphtheria.
• Lingual squamous cell carcinomas occur more commonly in fields.
• Fibrosarcoma is a malignant tumor composed of proliferating trabeculae of squamous epithelium.
• Epulis is a gingival growth.