Digestive System wks 1-3 Flashcards
Which teeth in the dog have three roots?
Upper P4, M1, M2
In what species are “needle teeth” found and what teeth are they?
Pigs. They refer to the 4 third incisors and 4 canines. These teeth are fully erupted deciduous teeth
What is characteristic of hypsodont teeth that differs to brachydont teeth?
Hypsodont teeth continue to grow (from their apical aspect) long after the tooth has erupted. Eruption itself continues for life to compensate for occlusal wear. Brachydont teeth do not continually erupt.
What is the “cup” or “mark”?
Also known as the infundibulum. The space filled with cementum due to folds which form in the cementum during development of the tooth. Known as the mark when we reach the base of it.
What is the “star”?
The pulp cavity in cross section of the tooth. It’s protected by secondary and sometimes tertiary dentine.
At what age do canine teeth appear in horses?
4-6 years. However they only appear in males (in the diastema) and only in some males. They are brachydont teeth.
The wolf tooth is…
The first premolar in horses. Only in 13%-32% and more commonly noted in females
Why do animals with hypsodont teeth have a convoluted enamel pattern on the grinding surface (“table”) of their teeth?
This forms due to the different rates of wear of the materials comprising the tooth. For example, enamel is a much stronger material than dentine or cementum and therefore slows down at a slower rate than them.
What are the ways in which we can assess the age of animals using their dentition?
- Eruption times (eruption of incisors)
- Changes to the incisor occlusal surface (including dental star, dental cup/mark, and changes to the shape of the occlusal surface)
- Shape of the upper corner incisor
- Curvature of dental arch of lower incisors
- Angle of incisors
- Hook present on upper corner incisor
- Galvayne’s groove
What are boundaries of the oral cavity?
Dorsal: hard palate and soft palate Caudal: palatoglossal arches Rostral: lips Ventral: floor of oral cavity Lateral: cheeks
What is the function of the oral cavity?
Prehension of food Mastication Insalivation of food Deglutition Taste Defence/ aggression Grooming Temperature regulation
The epithelium of the oral mucosa has ____________ ______________ ____________ cells.
Stratified squamous epithelial cells
What is the layer of connective tissue directly underlying the external epithelium and making up the oral mucosa?
Lamina propria
What muscles are associated with the oral cavity and what nerve are they innervated by?
Caninus
Levator labii superioris
Depressor labii inferioris (in cat only)
Levator nasolabialis
All innervated by the facial nerve (CN VII)
What is the cleft marking division in the upper lip of dogs, cats, camelids and sheep?
Philtrum
The muscle responsible for returning food from the outer vestibule to the oral cavity is the…
It is innervated by…..
Buccinator
Facial nerve (CN VII)
What are rugae?
Ridges/ folds on the hard palate or stomach
Palatine glands are present in all species except….
Pigs! 🐷🐷🐷
The bones comprising the palate are…
Palatine, maxilla, incisive
The function of the frenulum is to…
Connect the tongue to the floor of the oral cavity.
What are the different forms of papillae?
- Filiform
- Conical
- Fungiform
- Lentiform
- Foliate
- Vallate (circumvallate)
- Marginal papillae (in newborn dog and pig to aid suckling)
Taste buds are clusters of specialised cells located within the epithelium of _________ _________. Nerves responsible conveying sense of taste include the________
Gustatory papillae.
Facial nerve (CN VII) and glossopharyngeal nerve (CN IX)
Muscles supporting the tongue include the…
Extrinsic muscles of the tongue are…
Innervated by…
Mylohyoideus and geniohyoideus.
Styloglossus, hyoglossus and genioglossus.
Hypoglossal nerve (CN XII)
General sensation in the rostral 2/3 of the tongue is innervated by ___________. In the caudal 1/3 it is ________. Taste in the rostral 2/3 is innervated by_______. In the caudal 1/3 it is ________.
Trigeminal-mandibular division of CN V
Glossopharyngeal (CN IX)
Facial nerve (CN VII)
Glossopharyngeal
Muscles of mastication include:
Temporalis, masseter, pterygoids, digastricus
The TMJ is the articulation between….
Zygomatic process of the temporal bone and the condylar process of the mandible.
The three parts of the pharynx are…..
Sensory and motor innervation are provided by…
Oropharynx
Nasopharyngeal
Laryngopharynx
Glossopharyngeal (CN IX) and vagus (CN X)
What does monophyodont mean? Give an example.
Only one set of teeth erupt and remain in function throughout life. There are no deciduous teeth. Includes rodents and dolphins.
What does polyphyodont mean? Example.
Many sets of teeth are continually replaced. Sharks and crocodiles.
What is a diphyodont?
Having two sets of teeth.