Oral Histology Flashcards
Most calcified & brittle substance in human body
yellowish to grayish
semi tranlucent
Enamel - 97% inorganic ( calcium & phosphorus)
2-4% organic
amelogenins- immature
enamelins- mature
Basic Structure
basic structural unit
fish tail, tad pole, racket
Thickest
thinnest
Enamel rod/ prism
Cusp tips
cervical area
intertwinning pathways of enamel rods
Gnarled enamel
covers the enamel rods
more mineralized than enamel rod
fish scale appearance
Enamel rod sheath
cements rods together/ between
Interrod enamel
Structural Characteristics
appositional/ incremental growth of enamel
- marks calcification of enamel
Incremental line of Retzius
represent lines of retries as they meet at the surface of enamel
Perikymata / Imbrication line of Pickerill
more pronounced incremental line
Neonatal lines
crosses bands of retzius
appositional growth of enamel of 4um/day
Transverse Striations
alternate dark & light bands
Hunter Schreger Bands
originate from DEJ
lateral spread ofm caries
grass like
Enamel Tufts
cracks on the surface of enamle
pathway for bacteria to penetrate the enamel
Enamel Lamellae
extensions of dentinal tubules that penetrate DEJ
- DEJ hypersensitivity
Enamel Spindle- from odontoblast
scalloped for attachment
DEJ
age changes
Attrition
Discoloration
Reduced permeability
