Embryology Flashcards
Homodont and Heterodont
Shape of the tooth
1. homo- all the same
2. hetero - different
Thecodont, acrodont, pleurodont
Anchorage of tooth
1. Thecodont - set in sockets
2. Acrodont - ankylosed directly to the bone
3. Pleurodont - grow from pocket
Brachydont, Hypsodont, Radicular hypsodont, Aradicular hysodont
Crown Type
1. Brachydont - short crown to root ratio
2. Hypsodont - longer crown to root ratio
3. Radicular hyps - closed roots with continuous eruption
4. Aradicular hyps - open roots with continuous eruption
Secodont, bunodont
Cusp type
1. secodont - cheek teeth with cutting cusp
2. Bunodont - cheek teeth with low cusps for grinding
Isognathous, Anisognathous
Jaw relation
1. Iso - equal
2. Anis- unequal
Dogs and cats have what kind of dentition
Diphydont – 2 sets of teeth
heterodont – diff shape
brachydont – short crown
Secodont - cutting cusp
Thecodont - sockets
Anis - different length
What day does the brachial arch form
What day does the brachial arch become maxilla and mandible
What day are teeth visible
Day 21
Day 23
Day 25
The dental papilla and Sac/Follicle become what
Papilla – pulp/dentin
Sac – PDL, cementum, alveolar bone
What stage does the stratum intermedium form
Bell stage
What are the three steps to tooth development
bud, cap, bell
from ectomesenchyme
What is the bud stage
budding of the dental lamina which makes the region of the decidous dentition
What happens in the cap stage
concavity of the bud
vascular supply
formation of the OEE/IEE/SR
What does the outer enamel epithelium do
Protective layer
What does the inner enamel epithelium do
Enamel formation
What is the stellate reticulum
Cushing and allows for nourishment to IEE
Where does the stratum intermedium form
Between IEE and SR
Name the layers
The enamel organ, papilla, follicle form what products from what cells
Enamel – what makes it and what is it made of, when is it formed
Ameloblasts via amelogenesis
Hydroxyapatite
formed in late bell stahe
What is nasmyth membrane
primary enamel cuticle
Protective layer of reduce enamel epithelium that is worn away with chewing
What does OEE and IEE become after crown formation
Herwigs root sheath
What gives rise to rests of malassez
Hertwig root sheath if fails to dissolve
Most prominent pattern of dentin and enamel (when etching enamel)
Enamel - type 1 with rods
Dentin - type 3
Dentinogenesis is what
formation of dentin
What components help form dentin
Odontoblasts
Odontoplasts help synthesize type 1 collagen, secrete proteglyceans, collagen, ALKP, eetc
what happens once HER contacts papilla
Start making odontblast
Hertwig’s epithelial root sheath begins to resolve
Malformation-> accessory or supernumerary root
What happens when the dental sac comes into contact with dentin
Starts making cementum
Where do permeant teeth erupt
MN C- lingual
MX C- mesial
Incsiors - lingual
Remainder buccal
What are the 3 stages of eruption
Preeruptive - end of crown formation
eruptive - root formation
posteruptive - into occlusion
What are the 4 eruption theories
- root - root pushes tooth forward
- Bone - bone deposits cause eruption
- PDL - PDL dorces push forward (most plausible)
- Dental follicle – continued growth causes tooth to erupt
Deciduous dentition dog and cat
Dog = 28( i3, c1, PM3). doesnt have PM1 as decdisous for maxilla and mandible
Cat = 26 (i3, c1, PM3/2)
Doesnt have molar teeth
Tombes fibers
Odontoblastic processes through predentin
Tomes processess
landmark in ameloblasts
What are the 6 cellular layers of dentin pulp complex
Dentin, predentin, odontoblast, cell free, cell rich, Pulp
Dentin is produced by
odontoblast
Pulp proper
Fibroblast
Type I/III collagen
Proteoglycan
GAG
Cell rich layer is composed of
fibroblasts
Cell poor layer is composed of
Traversed by capillaries, unmyelinated nerve fibers, cytoplasmic processes of fibroblasts
What type of collagen is made by odontoblast vs fibroblast
Fibro - I, III, V, VII
Odonto - I
Pulpal blood flow
Capillaries
Highest in horns, –coronal portion – lowest in root
Plexus of Raschkov
Nerve plexus in root
Most prominant nerve fibers in pulp
C fibers
A delta fibers
What fibers are stimulated with electric and cold pulp testing
A fibers
