Lecture 2 Flashcards
abnormal buildup of cementum (especially at the apex)
hypercementosis
what is the chemical composition of cementum?
45-50% inorganic
50-55% organic
- First to form
- Covers the cervical 1/3-1/2
- Formed BEFORE the teeth are in occlusion
- Does NOT contain cells
- Calcified Sharpey’s fibers (the ends of the PDLs)
- Collagen fibers are parallel to the root
Which type of cementum?
acellular/primary cementum
- Formed AFTER teeth reach occlusion
- More irregular than acellular
- Contains coenocytes (making them “cellular”)
- Less calcified
- Resembles bone
which type of cementum?
cellular/secondary cementum
what are the functions of cementum?
- attachment
- protection
- passive eruption
cementum is _____ susceptible to resorption than bone
less
when does the alveolar process develop?
during the eruption of teeth
when teeth are lost, what happens to alveolar bone?
it will resorb
the surface of the alveolar bone that faces ether the buccal/facial or the lingual/palatal surfaces
external plate of cortical bone
the middle layer of alveolar process between the external plate and inner socket wall
cancellous trabeculae
the inner layer of alveolar process that is closes to the tooth
inner socket wall
(alveolar bone proper)
what is the chemical composition of alveolar process?
1/3 organic (T1 collagen)
2/3 inorganic (hydroxyapatite)
during situations like orthodontic treatment the alveolar bone is resorbed on the side that the tooth is being pushed to (the compression side) and deposited on the other side (the tension side)
what is this process called?
remodeling
extra bone along the alveolar bone on the buccal/facial side of either the maxillary or mandibular arch (basically the same thing as mandibular tori only it is on the facial/buccal side and can be on the mandible or maxilla)
exostosis
a “window” to the root surface that is surrounded by bone
fenestration
a U-shaped area extending from the coronal surface of the alveolar bone apically
dehiscence
the _____ provides an adaptive apparatus that supports the teeth during mastication
PDL
true or false?
the PDL is very cellular and vascular
true
the ends of the principal fibers and are imbedded into the alveolar bone and cementum
sharpey’s fibers
the part of the fiber that is between the Sharpey’s fibers on both ends.
principal fibers
goes over the alveolar crest between teeth, imbedded in cementum at both ends, always present.
which group of principle fibers?
transseptal group
extends obliquely from the CEJ down to the alveolar crest prevents extrusion and resists lateral movements breakage of these fibers does not increase mobility of the tooth.
which group of principle fibers?
alveolar crest group
extend out from the tooth at a 90-degree angle anchoring into the cementum on one end and alveolar bone on the other end
which group of principle fibers?
horizontal group
largest group, one end attaches to the alveolar bone then the fiber extends inferiorly and obliquely to the cementum *withstands chewing forces on the tooth
which group of principle fibers?
oblique group
