4D 2.4 Hard Tissue Biology Flashcards
name the marked features
what ar ethe ideal properties of tooth
Strong
Hard
Wear resistant
Resistant to chemical damage
Ability to respond to insult/damage
Ability to repair
Aesthetic
what is the main structural feature of enamel
enamel prisms
what does the enamel cover
anatomical crown
what percentage of hydroxyapatite is found in enamel
96%
whats harder the enamel or the dentine
enamel is harder
enamel (KHN 360-390)
dentine (KHN 75)
enamel bur needs to be used to cut through enamel
what are the three requiretments for the drill
high speed
diamond
tungsten carbide
what is the risk of having an un-supported enamel
easily fractured with a hand instrument
what is dentines mineral and collagen composition
70% mineral
20% collagen
describe the direction of collagen fibres in the dentine
follows the shape of the enamel
carious dentine is soft. what bur or instrument would be used to cut through it.
bladed bur or hand excavator
sound dentine is less hard than enamel
what two options are availble when cutting
diamond burs - high speed
bladed burs low/high speed
there are tubules present in dentine, which carry on to the pulp (15k to 65k per mm2)
what may tubules contain
cell processes
nerves
fluid - flows out
would you find more tubules per mm2 in the amelodentinal junction or the predentine
predentine
how do fillings bond to dentine
resin