Perio 2

Question 1

origins of cementum

Answer 1

cells in dental follicle become cementoblasts. Either HERS or dentin induces cells to become cementoblasts or HERS cells become cementoblasts themselves.
HERS that breaks off = rests of malassez, remain attached become enamel pearls

Question 2

Cementum composition

Answer 2

similar to bone, thinner at CEJ and thicker at apex, light yellow color, hydroxyapatite, most organic is collagen type 1, few type 3 and 12.
50% organic 50% inorganic

Question 3

CEJ

Answer 3

60% overlap
30% meet
10% gap

Question 4

cementum types

Answer 4

• acellular (primary) no cells inside it. extrinsic fibers. attachemnt. coronal 2/3
• cellular (secondary) intrinsic fibers apical 1/3- adaption/repair
• classified by presence of encapsulated cells and predominant origin of collagen fibers
• collagen fibers either extrinsic from PDL or intrinsic form cementoblasts

Question 5

acellular extrinsic fiber cementum formation

Answer 5

primary
cementoblasts send process into predentin and produce collagen fibers (fibrous fringe)
forms CDJ
collagen fibers from PDL merge with fibrous fringe and mineralize
cementoblasts end up on surface of cementum

Question 6

cellular intrinsic fiber cementum formation

Answer 6

starts similar with intermingling to create CDJ, cementoblasts become trapped in advancing cementum, cementoid visible at surface, frist rapid stage of growth then slower regular deposition.
collagen fibers produced by cementoblasts not pdl

Question 7

intermediate cementum

Answer 7

betwen granular layer of tomes and dental cementum proper
minerlaized level higher
may function to seal surface of root dentin and to reduce sensitivity

Question 8

mixed cementum

Answer 8

alternating layers of AEFC and CIFC
generally located apically
perhaps a bunch of secondary cementum is actually mixed

Question 9

hypercemntosis

Answer 9

abnormal thickening of cementum, diffuse or circumferential around whole root
can affect entire dentition or just portions of one tooth
tooth can become ankylosed

Question 10

tooth movement

Answer 10

cementum is more resistant to resorbtion than bone

so bone tends to get remodeled first

Question 11

tipping

Answer 11

tooth crown and apex go different ways

Question 12

bodily

Answer 12

whole tooth goes one way

Question 13

extrusive

Answer 13

movement towards occulsal surface

Question 14

intrusive

Answer 14

movement towards apices

Question 15

rotational

Answer 15

tooth twist

Question 16

factors that determine the degree of effect of the applied force

Answer 16

transduction: efficiency of the conversion of physical force into biological response
time- how long its applied
magnitude of force- degree of force determines response

Question 17

compression

Answer 17

on side of tooth towards movement

resoprtion of alveolar bone

Question 18

tension

Answer 18

on opposite side of tooth where bone is moving

formation of alveolar bone

Question 19

hyalinization

Answer 19

too great or rapid compression force
loss of cell activity and vasculariuty
PDL has to repopulate before moving continues

Question 20

undermining resorption

Answer 20

occurs in conjugation with hyalinization

resorption occurs on opposite surface of compressed bone