1. Anatomy Flashcards
What is the difference between parakeratinized and orthokeratinized nuclei
Parakeratinized has nuclei
Orthokeratinized does not
Name the clear cells
- Merkel - Sensory
- Langherhan - Defense present antobodies
- Melanocytes - Produce melanin
What is the normal radiographic width of PDL space
0.01 - 0.25 mm
What is the turnover of Junctional Epithelium
1 - 6 days.
What are the 2 layers of the basement membrane
- Papillary
2. Reticular
What is the blood supply to the PDL
Superior and Inferior Alveolar Arteries
What is the difference between woven bone and lamellar bone
Woven Bone: Immature bone with osteoblasts and calcified collagen fibers
Lamellar: More mature bone
Where is Lamellar bone found
Cortical Bone
Where is bundle bone found, what does it belong to?
Around the tooth, it belongs to the tooth
It is 1 mm thick
It resorbs following extraction of teeth no matter what
What type of collagen is present in bone
Type I
What are the stages of tooth development
- Bud
- Cap
- Bell
What are ameloblasts derived from
Enamel Organ / Dental Organ
What is formed from the dental papilla
- Pulp
2. Dentine
What is derived from the dental follicle
- PDL
- Bone
- Cementum
Discuss how root structure develops starting at the bell stage
IEE + REE combine to form cervical loop
Cervical loop divides into Hertwigs Epithelial Root Sheath
Papilla contacts HERS - forms osteoblast
Follicle brakes down, causing cementoblast to differentiate exposing dentine
Further away fibroblast between collagen form PDL
How does active eruption occur
Oblique orientated fibers pull down the tooth
How does attachment of JE to tooth surface develop
Primarily from OEE and REE
Discuss cementum
Acellular / Cellular
Made of type I and III collagen
Primary acelluar cementum laid down first, has intrinsic fibers
As this thickens it meets the PDL and traps fibers called extrinsic fibers
What are Sharpeys fibers
Fibers trapped in bone
What is secondary cementum
Cellular cementum in the apical 1/3