EX2; Periodontium - Cementum

Question 1

What are the three main functions of cementum

Answer 1

attachement
protection
adaptation (to the physiological forces of mastication

Question 2

What is the composition of cementum

Answer 2

45-50% organic

50-55% inorganic (but can vary)

Question 3

What makes up the organic component of cementum

Answer 3

90% collagen (90:10 type I to type III)
non-collagenous proteins
ground substance

Question 4

True or False

Cementum is not vascularized

Answer 4

True

Question 5

True or False

Cementum does remodel

Answer 5

False; it does not remodel

Question 6

What is the main difference between cementum and bone

Answer 6

cementum is secreted throughout life, but not normally resorbed

Question 7

Where is cementum the thinest/thickest

Answer 7

thinest = ~CEJ (vulnerable)
thickets = towards the root apex

Question 8

What are the different types of CEJ joints

Answer 8

overlap (60%)
butt against (30%)
gap (10%)

Question 9

Primary cementum is composed of what

Answer 9

acellular extrinsic fiber (AEFC)

Question 10

What does extrinsic refer to in talking about AEFC

Answer 10

the fact that the organic matrix of cementum is secreted by cementoblasts and PDL fibroblasts that do NOT become entrapped in the cementum

Question 11

Acellular extrinsic fiber cementum is considered to play the most important role in what

Answer 11

attachment

Question 12

These constitute the mineralized ends of the PDL fibers

Answer 12

Sharpey’s fibers

Question 13

This consists of collagen fibers oriented parallel to the surface of the cementum with no clear connection to the PDL

Answer 13

cellular intrinsic fiber cementum (CIFC); type of secondary cementum

Question 14

This comprises the bulk of secondary cementum

Answer 14

mixed fiber cementum

Question 15

What type of fibers does mixed fiber cementum contain

Answer 15

intrinsic (parallel)
extrinsic (perpendicular)
perpendicular plays the roll in attachment

Question 16

When is mixed fiber cementum secreted

Answer 16

after and more slowly than the initial wave of secondary cementum, more prominent apically

Question 17

Where is the secondary cementum most thick

Answer 17

in places in response to occlusal forces

Question 18

These were originally cementoblasts, entrapped in the mineralizing extracellular matrix

Answer 18

cementocytes

Question 19

True or False

Cementocytes are actively participating in synthesizing cementum

Answer 19

False; they are not

Question 20

The rate of cementum formation varies based upon what

Answer 20

environmental factors

Question 21

An increase in cementum production has been associated with what

Answer 21

attrition

periodontal disease accompanied by pronounced inflammation

Question 22

Continued deposition of cementum can cause the size of what to become progressively smaller

Answer 22

the apical foramen

Question 23

Where are the cementoblasts located

Answer 23

lying at the end of the PDL, their long axis parallel to the CEJ

Question 24

The outmost layer of cementum directly adjacent to the cementoblasts is sometimes unmineralized, and called what

Answer 24

cementoid

Question 25

These are similarly found in dentin and enamel, apparent in layers in the cementum

Answer 25

growth lines

Question 26

This is excessively large amounts of cementum deposition (around the root)

Answer 26

hypercementosis (relatively rare)

in the case study; the patient presented with gingival recession but no pain