Ex 2- Periodontium 2- Cementum

Question 1

What are the 3 main functions of cementum?

Answer 1

attachment
protection
adaptation (to physiological forces of mastication)

Question 2

Cementum is a hard connective tissue with a composition similar to bone ___-__% organic & __-__ % inorganic

Answer 2

45-50

50-55 (can vary)

Question 3

The organic portion of cementum is 90% collagen( ___% type I and ___% type II), non-collageneous proteins and ground substance

Answer 3

90

10

Question 4

Cementum is not _______ and does not ________

Answer 4

vascularized

remodel

Question 5

Cementum is secreted ______ _____ but is not normally ______ (makes it different from bone)

Answer 5

throughout life

resorbed

Question 6

Cementum increases __X between ages 16-70

Answer 6

3

Question 7

Cementum is thinnest at the _____ (20-50um) and is thickest at the ______ _____

Answer 7

CEJ (vulnerable spot)

root apex

Question 8

What are the 3 basic forms of the CEJ?

Answer 8

overlaps enamel (60%)
butt up to enamel (30%)
gap btw enamel + cementum (10%)

Question 9

Primary cementum is found more _______ and secondary cementum more ______ though the two types overlap somewhat in the middle of the tooth

Answer 9

coronally

apically

Question 10

Primary cementum is mainly composed of ______ _____ ______ cementum

Answer 10

acellular extrinsic fiber (AEFC)

Question 11

________ refers to the fact that the organic matrix of cementum is secreted by cells (cementoblasts + PDL fibroblasts) that do NOT become entrapped in the cementum

Answer 11

extrinsic

Question 12

Acellular extrinsic fiber cementum is considered to play the most important function in _______

Answer 12

attachment

Question 13

The collagen matrix of acellular cementum consists mostly of fibers oriented at ______ angles to the cementum surface

Answer 13

right

Question 14

________ ______ constitute the mineralized ends of PDL fibers

Answer 14

Sharpey’s fibers

Question 15

Secondary cementum is made up of _____ _____ _____ cementum which consists of collagen fibers oriented _____ to the surface of cementum, with no clear connection to the PDL

Answer 15

cellular intrinsic fiber (CIFC)

parallel

Question 16

_______ because the cementoblasts that secreted the organic matrix become entrapped in the cementum (cementocytes)

Answer 16

Intrinsic

Question 17

______ _______ ______ comprises the bulk of secondary cementum

Answer 17

Mixed fiber cementum

Question 18

Mixed fiber cementum contains __ types of fibers: _____ fibers are parallel to the long axis and ______ fibers that are perpendicular and continuous w/ Sharpey’s fibers

Answer 18

intrinsic 
extrinsic (role in attachment)

Question 19

Mixed fiber cementum is typically secreted _____ and more _____ than the initial wave of secondary cementum, and so is more prominent even further apically

Answer 19

after

slowly

Question 20

Mixed fiber cementum is prominent in the __________ region of multi-rooted teeth

Answer 20

interradicular

Question 21

Secondary cementum thickens the most in response to _______ ______

Answer 21

occlusal forces

Question 22

_______ were initially cementoblasts laying down cementum matrix and as cementum was formed they became entrapped in the mineralizing extracellular matrix

Answer 22

cementocytes

Question 23

Cementocytes are no longer involved in synthesizing _______ and are considered to be inactive

Answer 23

cementum

Question 24

Cementum like dentin is laid down _______ ______ and the rate of deposition varies depending upon ______ ____

Answer 24

throughout life

environmental factors

Question 25

An increase in cementum production has been associated with ______ in the crown and ______ ______ with pronounced inflammation.

Answer 25

attrition

periodontal disease

Question 26

Continued deposit of cementum can cause the size of the ______ _______ to become progressively smaller

Answer 26

apical foramen

Question 27

Cementoblasts in the mature tooth are located at the edge of the _____. Their long axis is parallel to the ____

Answer 27

PDL

CEJ

Question 28

The outermost layer of cementum directly adj to the cementoblasts is sometimes unmineralized and called _________

Answer 28

cementoid

Question 29

Similar to dentin + enamel, ______ _____ can be seen in cementum giving cementum a striped appearance

Answer 29

growth lines

Question 30

When very large amounts of cementum are deposited around the root the condition _______ results. A relatively rare procedure.

Answer 30

hypercementosis