Path 2 - Alimentary 1

rilohoji's version from 2016-11-25 20:59

Facial/Oral Malformations

Question Answer
What is Cheiloschisis? What is happening?1° CLEFT LIP/harelip. Czd by incomplete fusion of the upper lip along the midline. Can be unilateral or bilateral, can be superficial (only lips involved) or deep (extends into the nostrils)
What is Palatoschisis? What is happening?2° cleft palate/ problems w/ the HARD palate (hard & soft if severe). Czd by incomplete fusion of the palatine PROCESSES (ie, bony hard palate). Animals cannot suckle properly & often develop aspiration pneumonia if they are at all successful. CAN BE DUE TO GENETIC OR TOXIC REASONS or steroid administration during pregnancy
Which cleft-palate condition means the babies will be unable to suckle & if they do, they get aspiration pneumonia?Palatoschisis (not Cheiloschisis)
What is brachygnathia?Shortening of the mandible (overbite)
What is prognathia?Protrusion of the mandible (underbite)


  = Dzs of the Teeth
Question Answer
Describe the normal development of teeth in the embryoGingival epithelium (ECTODERM) invaginates downward into the underlying mesenchyme, forming the cup-shaped dental lamina.
What are the 3 structures that arise from the cup-shaped dental lamina (DL formed from the 1st step)(1) Enamel organ
(2) Dental papilla
(3) Dental follicle
What does the enamel organ form? How?Gives rise to ENAMEL, which is PRODUCED BY AMELOBLASTS
What do the dental papillae give rise to (2)? Each part is formed by what/any notes?(1) Dental pulp - Formed from mesenchymal tissue enclosed by the cup-shaped dental lamina
(2) Dentin - Formed by odontoblasts. It is formed w/ tubules which run through it (odontoblast's cell processes go through the tubes so they can continually renew dentin matrix) (papillae, pulp. also dentin, so papillae look like reverse dents)
What does the dental follicle give rise to?Gives rise to cells that produce cementum (cementoblasts), the bony sockets of the teeth (osteoblasts) & the periodontal ligament (fibroblasts). Cementum covers the dentin below the gum line (simple teeth) (Foiled by follicles!! they cemented fibers onto my bones)
What is a simple tooth aka? Who/where are they found?Aka brachydont teeth. Found in carnivores & in pigs (except the tusks of boars). The lower incisors of ruminants are also brachydont teeth.
What are the parts of a simple tooth?3 parts are:
(1) Crown (exposed portion covered w/ enamel)
(2) Root (below gum line, dentin covered w/ cementum)
(3) Dental pulp (well vascularized & innervated portion of tooth which nourishes the odontoblasts w/in the dentin). (Also there is a #4, he didnt really go into it much, but it's the fact that there's a fibrous periodontal ligament which holds the tooth into the tooth socket (alveolus)
What is a complex tooth aka? Who/where are they found? When do they erupt & what is their growth like?Aka hypsodont teeth. They are the cheek teeth of ruminants (not the front/incisors tho), the tusks of pigs/boars, all of the teeth in horses, rabbits & rodents. They erupt & grow continually throughout life, so they MUST be ground down via mastication.
Describe what the hypsodont/complex tooth looks like/its structureRoot+crown both covered in cementum & there is no demarcation btwn the 2. Enamel is btwn the cementum & dentin. Cementum & enamel invaginate into the dentin on the surface of the tooth forming the infundibulum (cups) of the tooth
What is Anodontia? Who do you usually see this in?No teeth. Rare, but most often seen in calves (think like how they already lack upper front teeth, so what's missing a few more?)
What is Oligodontia? What is this a sequela from?Too few teeth. Usually czd by failure or delayed eruption of teeth (rare).
What is Polyodontia? Who do you often see this in? What is PSEUDOpolyodontia?Too many teeth. Observed in the incisors of brachycephalic breeds of dogs. "Pseudopolyodontia" is from retained deciduous teeth
Dentigerous cysts (aka?/common name?) what is usually happening in here & who does this usually happen in?AKA heterotrophic polyodontia. Usually "ear teeth" in HORSES. Epithelial lined cavity (may contain keratin & abnormally formed tooth) which is usually anterior & below the ear
Enamel Hypoplasia usually happens in what fashion? What happens? What is it czd by?Usually happens in a segmental fashion (not the entire enamel at once) & is czd by damage to the ameloblasts → damage can be from VIRUSES (distemper virus in young dogs (up to 6 months of age) & BVD virus in calves infected in utero) OR damage can be from a ↑ FEVER in young animals when their teeth are developing
Explain Chronic fluorosis-what do the teeth look like? What czs this/sources of this? What might be protective against this, for who?If there is ↑ fluoride during development of the teeth (6-36mo depending on spp) can result in incorporation of the fluoride into dentin & enamel causing soft, chalky, discolored (yellow to dark brown to black) spots in the enamel. bc they're softer, tooth wear occurs quickly. SOURCES of excessive fluoride are aluminum smelting plants & ground water in certain locations. ~Selenium appears to be protective in cattle
Congenital porphyria is aka? What is it, what is going on? Where does it affect aside from teeth?Aka pink tooth. there is a deficiency in uroporphyrinogen III cosynthetase, an enzyme which malfxns & czs there to be defective heme pigments in RBCs. Porphyrins build up in bloodstream bc of these defective hemes & the prophyrins (coproporphyrin I & uroporphyrin I) are deposited into the dentin in teeth. This makes the teeth look pinkish. They are also deposited in the skin (can cz photosensitivity) & also the bones. Also comes out of the urine (porphyrinuria) (there is a chart on the PPT, idk if it'll be important)
What is an ABx which can cz tooth discoloration? Explain what's going onTETRACYCLINE. If you give tetra to an animal while their teeth are developing, the tetra will be incorporated into the teeth minerals. The result is a permanent yellowish discoloration to the teeth
What is pulpitis? When does this usually happen?Inflammation of the dental pulp. Usually 2° to tooth damage
What is Dental caries? Who is it most common in? What is going on?WAY more common in ppl than in animals. Demineralization of enamel & dentin by acids from foods & bacterial breakdown of food products. Soft, demineralized areas allow for additional damage by invading bacteria. Pulpitis may occur bc of this
Infundibular impaction is aka? What is happening, what is the result & most often in who?Infundibular necrosis or infundibular caries. A condition observed in hypsodont teeth. Food material gets trapped in the infundibulum which czs demineralization & loss of cementum & enamel. This can lead to pulpitis, then tooth abscesses w/ fistulous tracts that can rupture to the outside or into a paranasal sinus. Most often in horses/cattle
Feline external resorptive neck lesions → what czs this? (what resorbs what?) What happens/what makes it worse once it starts?It is IDIOPATHIC. The resorptive neck lesions are 2° to odontoclastic resorption of cementum in the neck+root of the tooth. osteoclasts invade resorptive cavity & then there is more resorption. Then food+plaque gets in there & czs 2⁰ inflammation+tooth loss
Periodontal dz usually results from what? What happens in the dz?Often 2° to buildup of bacterial plaque on the tooth adjacent to the gingival surface. Damage to adjacent gum tissue by mechanical means & by products from bacteria w/in the plaque. Then the gums atrophy/form fibrous pockets, which more food gets packed into & more bacteria grow in there. Pyorrhea (Periodontitis) results
What is Step mouth?Dental condition where 1 molar or premolar is longer than the teeth adjacent to it (horses usually)
What is Wave mouth?Like step mouth (1 molar or premolar is longer than the teeth adjacent to it) but MORE than 1 molar or premolar is longer than the adjacent teeth
What is Shear mouth? What would a normal value be, to compare this?Grinding surfaces of the molars or premolars are severely sloped medially or laterally creating sharp points that damage adjacent buccal mucosa or mucosa of tongue. Normal slope is somewhere around 15%
What are "hooks" & "ramps" ?Types of shear mouth, where hooks are angled points coming down from the top arcade & ramps are sharp angles pointing up from the lower arcade
Which animal has the most problems w/ teeth being the wrong SHAPE/abnormal wear? How do you fix it?HORSES & you float (sand down/grate) the teeth
Which animals have the biggest problem w/ an OVERGROWTH of teeth?RODENTS/RABBITS (esp a problem if the teeth are misaligned so they dont grind together)