Enamel Structure Flashcards
(20 cards)
Incisors
Cut or shear food, phonetics, functions and esthetics
Canines
Seize, pierce, tear and cut food,
Longest roots, key to protection
Premolars
Grind and tear
Fine chewing
Molars
Large, crushing grinding chewing
Enamel
Hardest tissue in body.
Striated because of rods that run all the way to the DEJ.
90-95% inorganic (HA)
Dentin
Yellowish, softer than dentin but still harder than bone, striated because of tubules
50% vol inorganic (HA), 25% vol collagen, 25% vol water
75% wt inorganic, 20% wt collagen, 5% wt water
Where does enamel come from?
Ameloblasts deposit and then dextinct.
Epithelial origin
Hardest enamel is the …
Gnarled enamel
Rods run from ____ to surface following a ____ pattern
DEJ, wavy
Where does dentin come from?
Mesoderm origin, odontoblasts remain in pulp
Dental tubule function
Allow fluid movement and ion transport (remineralization, apposition if peritibular dentin, pain reception)
Odontoblastic processes
Cytoplasmic extensions of cell body (tomes fibers)
Odontoblasts
Cell bodies line the wall of the pulp chamber
Principal organic compound in dentin is…
Collagen
Predentin
Unmineralized zone of dentin immediately adjacent to cell bodies of odontoblasts
Primary dentin
First dentin formed, up to 3 years after teeth erupt
Secondary dentin
Without and obvi stimulus, dentin direction changes and deposition slows
What part of the tooth is 100% repairable (as long as pulp is okay)?
Dentin
Name the 4 dental pulp functions
Formative or developmental (repairs, makes new dentin)
Nutritive (supplies nutrients and moisture to dentin thru blood vessels)
Sensory or protective (ONLY HAS PAIN RESPONSE, can feel temp)
Defensive it reparative (deposition of reparative dentin, inflammation when hurt)
Cementum
Hard, avascular dental tissue covering an atomic roots, formed continually through life. Formed by cementoblasts.
Light yellow, slightly lighter than dentin
Rarely seen clinically
Removed by polishing and abrasion
Highest floride content
