Odontogenic Cysts - radicular cysts

Question 1

What is a cyst?

Answer 1

Pathological cavity filled by a fluid or a semi-fluid which has not been created by pus accumulation

They jaws are the most common bones affected by cysts

Question 2

What bone is the most affected by cysts?

Answer 2

Jaws

Question 3

Cyst vs abscess?

Answer 3

Abscess has pus

Cysts has a fluid

Question 4

Cysts of the jaws types/categories?

Answer 4

Epithelial cysts- odontogenic or non odontogenic

Non-epithelialized primary bone cysts

Question 5

2 types of cysts?

Answer 5

Costs of the jaws

Soft tissue cysts

Question 6

What are odontogenic cysts?

Answer 6

Cysts with an epithelial lining that originates from
residues of tooth forming enamel organ.

Question 7

Origin of odontogenic cysts?

Answer 7

Rests of serres - remnants of dental lamina

Rests of malassez - remnants of hertwogs root sheath

Reduced enamel epithelium

Question 8

2 types of odontogenic cysts?

Answer 8

Inflammatory

Developmental

Question 9

Types of inflammatory odontogenic cysts?

Answer 9

Radicular

Paradental - not as common

Question 10

Types of developmental cysts?

Answer 10

• Dentigerous cyst
• Eruption cyst
• Lateral periodontal cyst
• Gingival cyst
• Glandular odontogenic cyst
• Odontogenic keratocyst

Question 11

What is the most common type of odontogenic cysts of the jaw?

Answer 11

Radicular

Question 12

Types of Radicular cysts?

Answer 12

Apical Radicular cysts

Lateral Radicular cysts

Residual cysts

Question 13

Rarest type of Radicular cysts?

Answer 13

Lateral Radicular

Question 14

Most common type or Radicular cysts?

Answer 14

Apical Radicular cysts

Question 15

What is shown here?

Answer 15

Radicular cysts

Question 16

Differential diagnosis?

Answer 16

Periapical granuloma

Periapical abscess

Radicular cysts

Question 17

What is shown here?

Answer 17

Lateral Radicular cysts

Question 18

Margins of a lateral Radicular cysts?

Answer 18

Formation next to lateral root tooth

Question 19

What is shown here?

Answer 19

Residual Radicular cysts

Question 20

How do residual Radicular cysts differ from Radicular cysts?

Answer 20

Involved tooth has been extracted

Question 21

Pathogens of Radicular cysts?

Answer 21

proliferation of rests of malassez within a periapical granuloma - develop into a cysts
- epithelium is not vascularised tissue - cells in centre have no blood supply so die/degeneration of central cells within a proliferating mass of epithelium = cavity lined with epithelium

epithelium start to proliferated due to neutrophils, GF, cytokines etc

Inflammatory stimuli

Bacterial endotoxins

Cytokines

GF

not all periapical granulomas develop into cysts

or degeneration of granulation tissues surrounded y proliferating epithelium
- area of necrosis leading to cysts formation

Question 22

Radicular cysts arise from what?

Answer 22

Proliferation of rests of malassez within a periapical granuloma

Question 23

Describe the lining of Radicular cysts?

Answer 23

Non-keratinised stratified squamous epithelial lining

Chronically inflamed fibrous tissue capsule

Question 24

2 types of epithelial cysts?

Answer 24

odontogenic and non-odontogenic

Question 25

What is the most common type of odontogenic cysts?

Answer 25

inflammatory - radicular

Question 26

2 most common types of cysts?

Answer 26

radicular and dentigerous

Question 27

Residual cysts?

Answer 27

cysts remains in jaw after tooth extracted radiolucency

Question 28

How do cysts appear on radiograph?

Answer 28

radiolucent lesions due to bone resorption radiopaque due to margin

Question 29

What type of tooth are radicular cysts associated with?

Answer 29

non-vital tooth

Question 30

Why are radicular cysts rare in primary dentition?

Answer 30

the tooth is usually extracted before cysts formation

Question 31

Clinical presentation of radicular cysts?

Answer 31

apical cysts associated with apices of non-vital teeth symptomless if small incidental findings on radiographs alveolar bone expansion when they enlarge may discharge through sinus most cysts do not grow or very large dimensions pain is rare unless superimposed by infection

Question 32

When do radicular cysts cause alveolar bone expansion?

Answer 32

enlargement of cysts

Question 33

How does the cysts cause bone expansion?

Answer 33

so much hydrostatic pressure in the cyts s causes pressur eon the bien and osteoclast ion the bine are activated and causes bone resorption also, bone make sup form it by firming layers of periosteum rate of expansion is greater than bony deposition leading to eggshell cracking

Question 34

eggshell crackling?

Answer 34

rate of expansion is greater than bony deposition thinning of cortex bone bulges into mucosa- appears as blue swelling

Question 35

eggshell crackling also called what?

Answer 35

oil can bottling

Question 36

What is the radiopaque margin of the radicular cysts continuous with?

Answer 36

lamina dura

Question 37

What is the shape of a radicular cysts?

Answer 37

round to ovoid periapical radiolucency

Question 38

Do all periapical granulomas develop into cysts?

Answer 38

no

Question 39

Microcyst formation?

Answer 39

degeneration of central cells within a proliferating mass of epithelium

Question 40

What is the origin of the epithelium of a cyst?

Answer 40

cell rests of malassez

Question 41

epithelium regular or irregular?

Answer 41

irregular as time goes by, it becomes more regular and uniform

Question 42

What type of radicular cysts is this?

Answer 42

pocket cysts

Question 43

Pocket cysts?

Answer 43

pocket cysts surround he root apex more prone to heal after endodontic tx

Question 44

What happens to the epithelium over time?

Answer 44

thinner stratified squamous epithelium and more regular inflamed cause surrounding it

Question 45

what happens to a radicular cysts over time?

Answer 45

the epithelial lining in established cysts is regular even thickness metaplasia gives rise to mucous cells respiratory epithelium cholesterol clefts, cant see fat in preparation- breakdown of red blood cells

Question 46

What is this?

Answer 46

rushton bodies hyaline eosinophilic bodies - can sometimes be found in radicular cysts. with inflammation cells produce them no clinical significance

Question 47

With time if the inflammation is more contained, what are the features of the radicular cysts?

Answer 47

the capsule become more fibrous and less cellular with time - less inflamed cholesterol clefts within the capsule giant cells associated with them

Question 48

What is the appearance of the cysts contents?

Answer 48

watery straw coloured fluid semi solid brownish paste like consistency shimmering appearance due to cholesterol crystals

Question 49

What are the contents of the cysts?

Answer 49

breakdown products - epithelial, inflammatory and connective tissue cells serum proteins - high level immunoglobulins water electrolytes cholesterol crystals

Question 50

How would you describe the contents of the cysts?

Answer 50

hypertonic - highly concentrated high osmolality of the cysts contents

Question 51

How does hypertonic nature of the cysts affect expansion?

Answer 51

leads to expansion of the cysts due to osmosis fluids move form the lower to higher conc of electrolytes movement of fluids into the cysts lumen cysts lining acts as a permeable membrane

Question 52

Does the hydrostatic pressure of the radicular cyst cause bone resorption?

Answer 52

yes water move in, cysts expands like a balloon (even on all sides) pressure = osteoclast activation and bone resorption

Question 53

is the cysts wall permeable or impermeable?

Answer 53

semi permeable