Teeth Flashcards
Define a heterodont and give a species examples
Different types of teeth within the same jaw (Mammals -> cats, dogs etc.)
Defines a homodont w/ spp example
All teeth are similar (fihs, amphibians, reptiles)
Define a diphyodont
Two sets of teeth (seen in mammals)
What is the difference between a hypsodont tooth and a brachydont tooth?
Hypsodont = high crowns (horses and ruminants) Brachydont = Low crowns (dogs, pigs)
In the modified triadan system, what are the permanent teeth quadrants labelled?
1, 2, 3 and 4. 1 = Upper right 2= Upper Left 3 = Lower left 4 = Lower right
Temporary teeth quadrants are labelled what?
5-8
How many incisors are present in the Triadan system?
3 (01, 02, 03)
How many canines are present in the Triadan system?
1 (04)
How many premolars are present in the Triadan system?
4 (05, 06, 07, 08)
How many molars are present in the Triadan system?
3 (09, 10, 11)
The modified Tridan system is based on what animal? And how many teeth are there ins each quadrant?
Pig - 11
What is the dental formula for a mare? Which teeth are missing?
- 0.3.3 - Upper - missing canine and first pre-molar
3. 0.3.3 - Lower - missing canine and fire pre-molar
What is the dental formula for a dog? Which teeth are missing?
Upper: 3.1.4.2 - missing lasy molar (4th pre-molar = carnasial tooth)
Lower: 3.1.4.3 - full set
What is the dental formula for a cat? Which teeth are missing?
Upper: 3.1.3.1 - missing 1st premolar, x10 and x11 molar
Lower: 3.1.2.1 - missing 1st and 2nd premolar (x06, x05) and x10 and x11 molar
Dental formula for a rabbit? Which teeth are missing?
Upper: 2.0.3.3 - missing= 3rd incisor, 1st premolar
Lower: 1.0.2.3 - missing = 2nd and 3rd incisor, 1st and 2nd pre-molar.
Outline the embryological development of the tooth
1: Bud stage. Line of epithelial cells condenses along jaw margins, invaginate to form dental bud. Surrounded by proliferating mesenchymal cells
2: Cap stage. Bud infolds to form dental cap, neural crest derived mesenchyme forms dental papilla. Remains connected to epithelium via cord of cells, give off-shoots to form more buds.
3: Epithelial cells => ameloblasts => form enamel
4: Mesenchymal cells => odontoblasts =>form dentine
5: Bell stage. Mesenchyme around bud forms vascular dental sac (dental follice). Inner layer forms cementoblasts => cementum. Outer layer form osteoblasts => alveolar bone
6: Enamel organ comprises stellate reticulum plus ameloblasts and outer enamel epithelium
7: Dental sac differentiates into the periodontal ligament
What forms the enamel in a developing tooth?
Ameloblasts
What dorms the dentine in developing tooth?
Odontoblasts
What do the osteoblasts form?
Alveolar bone
What is the sensory nervous supply to the maxilla teeth?
Trigeminal V2 - Infraorbital nerve
What is the sensory nervous supply to the mandibular teeth
Trigemnial V3 - Mandibular nerve
What is the eruption times of deciduous teeth in horses?
Di 1= 6 days, Di 2= 6 weeks Di 3 = 6 months
3 Pre-Molars = 2 weeks
What is the eruption time of permanent teeth in horses?
I1 = 2.5 years, I2 = 3.5 yrs, I3 = 4.5yrs
C = 4-5 years
PM1 (Wolf) = 6 months, PM2 = 2.5yrs PM3 = 3yrs, PM4 = 4 yrs
M1 = 1 year, M2 = 2 year, M3= 4 year
What is Galvayne’s groove?
Appears on the lateral aspect of I3, appears at 10 years of age. At 15 year will be halfway down the tooth. 20 years is full developed.
When do cattle’s incisors erupt?
2 years old
