Odontogenic Cysts

Question 1

Treatmet of all ondontogenic cysts is E&C with extraction of associated teeth (Per Dr. Carlson)

EXCEPT?

Answer 1

No treatment

• Eruption cyst
• Gingival cyst of newborn

Excision

• Peripheral COC, Peripheral GOC

Question 2

Role of marsupialization in odontogenic cysts

Answer 2

Only for large OKC

Marsupialization for 6-12 months leads to regression of size, but doesn’t change presence of daughter cysts

Question 3

This odontogenic cyst is difficult to differentiate from mucoepidermoid carcinoma

Answer 3

Glandular Odontogenic Cyst

Question 4

Why does this cyst have distinct pericoronal radiolucency?

What is tissue of origin?

Answer 4

Dentigerous cyst

Fluid collects between crown and reduced enamel epithelium

Question 5

3 most common Odontogenic cysts

Answer 5

1. Periapical (non-vital teeth, cystic degeneration of rests within granuloma)
2. Paradental (vital partialy) erupted 3M
3. Dentigerous (vital impacted tooth, soft tissue twin is eruption cyst)

Question 6

Radiographic features of OKC

What % are multilocular?

Answer 6

Cortical expansion, thinning, perforation

Tooth displacement

75% unilocular

Question 7

Calcifying Odontogenic Cyst (gorlin’s cyst)

Site predilication

Relationship to odontomas

Histology classic finding

Answer 7

Maxilla=Mandible

Can occur with odontomas (thought to be neoplastic in these cases)

Obviously, vital tooth

Ghost cells (eosinophilic but no nucleous) within thickened cyst wall

Question 8

Histology and management of Glandular Odontogenic Cyst

Answer 8

Anterior mandible

Painless swelling

Multicystic odontogenic cyst with goblet cells, mucous pooling

WLE or E&C (higher recurrence/persistence)

Question 9

Presence of daughter cysts in OKC

Syndromic vs Non-syndromic

Answer 9

Syndomic 63%

Non-syndromic 42%

(Carlson, Oreadi 2015)

Question 10

This odontogenic cyst has this gene mutation affecting what signaling pathway?

Answer 10

OKC

PTCH gene (tumor supressor gene)

Hedgehog signaling pathway

(PTCH1 normally supresses activation of SMO/smoothened which is a cell cycle activator. If PTCH mutated, then it stops supressing SMO activation regardless of Hedgehog presence)

Question 11

Major criteria of NBCCS

Answer 11

Question 12

Which lesion has the histologically thinner epithelial cysts lining?

Dentigerous vs OKC

Answer 12

OKC is only 6-8 cells thick

Question 13

What is less agressive/reoccuring cousing of OKC?

Answer 13

OOC

Orthokeratinized Odontogenic cyst

Question 14

Soft tissue counterpart of lateral periodontal cyst?

Originates from what cells?

Answer 14

Gingival cyst of adult

Blue nodule on attached gingiva

Mandibular premolars just like LPC

Rests of Serres (Unlinke LPC which is Malassez)

Question 15

Recurrence rates of OKC at 5 years

Answer 15

Marsupialization with secondary E&C = 0%

E&C alone = 14%

(Carlson, Oreadi 2015)

Question 16

This cyst is found in place of normal or supernumerary tooth.

Origin is therefore enamel organ.

Answer 16

Primordial cyst

Question 17

Location of Odontogenic Epthelial Rests

Answer 17

• Dental lamina is within gingiva and degrades to Rests of Serres
• Rooth sheath is around bone/pdl and degrades to Rests of Malassez