Enamel Tissue Flashcards
Which tissue is the hardest of the 4 mineralized tissues of the body?
enamel
Of the 4 tissues of a tooth, which is the only that is NOT a connective tissue?
enamel
Enamel is derived from what tissue?
ectodermal derived tissued formed by a specialized epithelial cell - ameloblasts
Of the 4 mineralized tissues, enamel is the only one that does not have an ___ or ___ formation stage.
unmineralized; preenamel
T/F. Enamel has a immature stage (partially mineralized) and a mature stage (fully mineralized).
True.
T/F. The ameloblast completes its enamel formative cycle once the thickness of enamel is reached at a site (most advanced coronally).
True.
Enamel is the ___ mineralized tissue to appear in a developing tooth, ___ is the first to appear.
second; dentin
T/F. Enamel is not subjected to malformations (genetic and external factors), age changes, and self-induced habits.
False, Enamel IS subjected to malformations (genetic and external factors), age changes, and self-induced habits.
T/F. Enamel does not have enclosed cells (acellular), nerves (aneural), blood vessels (avascular), or lymph vessels (alymphatic).
True.
Which tissue is the most clinically significant?
enamel
What is the value for enamel on the Mohs mineral hardness scale?
5
Enamel can withstand ___ and impact forces well but is ___ without dentin support.
shearing; brittle
Enamel appears ___ and its hue depends on location, surface conditions of enamel, attraction to stain substances, and ages changes.
translucent
T/F. Enamel does NOT need a wet environment to maintain its integrity.
False. Enamel DOES need a wet environment to maintain its integrity.
Define attrition.
Normal, slow wearing away of tooth substances under the stress of mastication.
Are abrasion and erosion normal or not normal?
not normal
___ are pathways for diffusion of small molecules, such as water, and ___ effects on pore walls lead to carious lesions.
Microporosity; electrochemical
In ___, mineral is returned to the molecular structure of enamel by way of the ___. When this is exceeded by demineralization, ___ occurs.
remineralization; saliva; caviation
What is the inorganic substance that makes up 96% by weight of enamel?
hydroxyapatite crystals. compared to the other 3 mineralized tissues they are larger and consist of more impurities (fluoride, carbonate).
What is the principal mineral component?
calcium hydroxyapatite
How much (by weight) does the organic substance make up of enamel?
1%
What is the main protein found in enamel?
amelogenin
How are the organic enamel proteins arranged?
in a lace-like pattern throughout the volume of enamel and closely associated with the surface of the crystals
T/F. Enamel contains collagen fibers.
False, enamel does not contain collagen fibers.
How is water distributed throughout enamel?
by way of micropores between crystals and proteins