Oral Surgery - Cysts and Tumours

Question 1

what is the definition of a cyst

Answer 1

pathological cavity filled with fluid or air - that is not filled with the accumulation of pus

Question 2

what are the broad classifications of odontogenic cysts

Answer 2

inflammatory - radicular, paradental, mandibular buccal bifurcation
developmental - dentigerous cyst, OKC, lateral periodontal, gingival, calcifying odontogenic cyst

Question 3

what are the three types of non-odontogenic cysts

Answer 3

nasopalatine duct cyst
staphne’s bone cavity
aneurysmal bone cyst

Question 4

what are radicular cysts

Answer 4

associated with non vital tooth
due to proliferation of epithelial rests of malassez (HERS)

Question 5

what are residual cysts

Answer 5

radicular cysts that remain in the jaws after an extraction of the affected tooth

Question 6

name histopathological aspects of radicular/ residual cysts

Answer 6

regular lining of non-keratinised squamous cell epithelium
deposits of cholesterol
vascular capsule
inflammatory infiltrate
rushton bodies

Question 7

what is the radiographic appearance of radicular/ residual cyst

Answer 7

round or oval
unilocular and well defined
uniform radiolucency

Question 8

what are paradental cysts

Answer 8

associated with PE 3rd molars where the inflammatory stimulus is periocoronitis

Question 9

what are mandibular buccal bifurcation cysts

Answer 9

occur in children and associated with buccal aspect of erupting FPM

Question 10

what is a dentigerous cyst

Answer 10

they embrace the whole crown of an unerupted tooth and attach at CEJ
lined with epithelium derived from reduced enamel epithelium (REE)
associated with impacted mandibular 8s

Question 11

what is an eruption cyst

Answer 11

overlies an erupting tooth
most frequently seen in deciduous incisors of FPMs

Question 12

what is the histopathology of dentigerous/ eruption cysts

Answer 12

thin regular layer of non-keratinising stratified squamous epithelium
capsule resembles dental follicle
myxoid areas
lined with reduced enamel epithelium

Question 13

how do dentigerous cysts present radiologically

Answer 13

round or oval
well defined unilocular
uniform radiolucency
attached to crown of unerupted tooth

Question 14

what is an OKC

Answer 14

arises from cell rests of serres (dental lamina)
has an unusual growth pattern with high risk of recurrence
grows mesio-distally before any bony expansion bucco-lingually

Question 15

what is the histopathology of OKCs

Answer 15

thin connective tissue wall
uninflamed
lined with parakeratinised stratified squamous epithelium
can lead to daughter cells

Question 16

how do OKCs present radiographically

Answer 16

oval
well-defined
uni or multilocular

Question 17

what syndrome is associated with OKCs

Answer 17

basal cell naevus (Gorlin Goltz)
multiple naevoid basal cell carcinomas of the skin

Question 18

what is orthokeratinised odontogenic cyst

Answer 18

uncommon developmental cyst
similar presentation to OKC
unilocular without epithelial proliferations or satellite cells

Question 19

what is the histopathology of orthokeratinised odontogenic cyst

Answer 19

prominent orthokeratinisation
flattened basal cell layer
no association with naevoid basal cell carcinoma syndrome

Question 20

what is a lateral periodontal cyst

Answer 20

associated with lateral surface of root (canine/ premolar region)

Question 21

what is the histopathology of lateral periodontal cysts

Answer 21

thin lining stratified squamous epithelium
similar to gingival cysts

Question 22

what are gingival cysts

Answer 22

appear on attached gingivae as less than 1cm pink/blue swellings
derived from rests of serres (dental lamina) in gingival or alveolar soft tissues

Question 23

what are gingival cysts that appear on the palate of infants termed

Answer 23

epsteins pearls

Question 24

what are glandular odontogenic cysts

Answer 24

mulitlocular
mainly in anterior mandible
high recurrence

Question 25

what is the histopathology of glandular odontogenic cysts

Answer 25

uninflamed fibrous wall lined by glandular cuboidal epithelium

Question 26

what is calcifying odontogenic cysts

Answer 26

benign lesion that are about 1-3cm diameter adjacent teeth displaced bony expansion occurs

Question 27

what is a nasopalatine duct cyst

Answer 27

non-odontogenic comes from epithelial remnants pf naso-palatine duct heart shaped on true maxillary occlusal radiograph

Question 28

what is the histopathology of naso-palatine duct cyst

Answer 28

stratified squamous epithelium lining also has respiratory cuboidal lining neurovascular bundles found in capsule

Question 29

what are three examples of non-epithelial cysts found in the jaws

Answer 29

solitary bone cyst staphne's cavity aneurysmal bone cyst

Question 30

what is solitary bone cyst

Answer 30

unknown aetiology varied size and radiolucency with irregular outline scalloping prominent

Question 31

what is stafne's idiopathic bone cavity

Answer 31

round or oval radiolucency lies below level of IAN

Question 32

how are cysts managed

Answer 32

referral initial consultation special radiographs - including plain film radiograph, CBCT or CT biopsy diagnosis treatment plan and discussion

Question 33

what are the treatment options for cysts

Answer 33

enucleation marsupialisation surgical resection

Question 34

what is cyst enucleation

Answer 34

removal of entire cyst lining and contents used for radicular, residual or keratocysts

Question 35

what are potential complications of cyst enucleation

Answer 35

damage to IAN communication with maxillary sinus pathological fracture of mandible risk of recurrence

Question 36

what is marsupialisation

Answer 36

removing part of the cyst and leaving the top uncovered useful for large simple cysts, keratocyst or dentigerous cysts

Question 37

what are complications of marsupialisation

Answer 37

needs further surgery to remove cyst long treatment time before completion chance of infection uncomfortable

Question 38

what is segmental resection

Answer 38

removal of cyst with margin of normal bone used for ameloblastoma and sarcoma

Question 39

what are the three types of origin of odontogenic tumours

Answer 39

epithelial mesenchyme mixed

Question 40

what are three examples of epithelial odontogenic tumours

Answer 40

ameloblastoma calcifying epithelial odontogenic adenomatoid odontogenic tumour

Question 41

what is an ameloblastoma

Answer 41

benign but locally destructive posterior mandible knife edged external replacement resorption of neighbouring teeth

Question 42

what are the two types of ameloblastoma

Answer 42

follicular plexiform

Question 43

what is follicular ameloblastoma

Answer 43

islands present in fibrous tissue stellate reticulum tissue no connective tissue capsule

Question 44

what is plexiform ameloblastoma

Answer 44

cells arranged in strands rather than islands stellate reticulum tissue no connective tissue capsule

Question 45

what is the management of an ameloblastoma

Answer 45

surgical resection with margin of 1mm sound bone

Question 46

what is an adenomatoid odontogenic tumour

Answer 46

benign unilocular radiolucency with internal calcifications surround crown of unerupted maxillary canine attaches APICAL to CEJ (not like dentigerous)

Question 47

what is the histopathology of adenomatoid odontogenic tumour

Answer 47

epithelial cells arranged in duct like structures rosette appearance patchy calcification and fibrous tissue capsule

Question 48

what is the management for an adenomatoid odontogenic tumour

Answer 48

surgical removal

Question 49

what is calcifying epithelial odontogenic tumour

Answer 49

benign radiolucency has internal radiopacities variable appearance pleomorphic epithelial cells with dark nuclei pink staining amyloid

Question 50

what is an example of an odontogenic mesenchymal tumour

Answer 50

odontogenic myxoma

Question 51

what is an odontogenic myxoma

Answer 51

benign occurs more in mandible well- defined radiolucency with thin corticated margin soap bubble appearance

Question 52

what is the histopathology of odontogenic myxoma

Answer 52

loose myxoid tissue with stellate cells islands of inactive odontogenic epithelium no capsule - locally invasive

Question 53

what is the management of an odontogenic myxoma

Answer 53

curettage or resection due to high recurrence rate

Question 54

what is the only mixed odontogenic tumour

Answer 54

odontoma

Question 55

what is an odontoma

Answer 55

benign tumour odontome supernumerary malformation of dental tissues (enamel = epithelial and dentine = mesenchyme)

Question 56

what are the two types of odontoma

Answer 56

compound = ordered structures appear as mini teeth (anterior maxilla) complex - disordered mass of dental tissues (posterior mandible)

Question 57

what is the aetiology of radicular/ residual/ lateral cysts

Answer 57

rests of malassez from HERS

Question 58

what is the aetiology of dentigerous cyst

Answer 58

reduced enamel epithelium

Question 59

what is the aetiology of OKC

Answer 59

rests of serres

Question 60

what is the aetiology of ameloblastoma

Answer 60

rests of serres rests of malassez reduced enamel epithelium