Odontogenic tumours and tumour-like malfunctions

Question 1

Classification system for odontogenic tumours and tumour-like malfunctions

Answer 1

Benign
- Od epithelium without Od ectomesenchyme (ameloblastoma and CEOT)
- Od epithelium with Od ectomesenchyme with hard tissue
- mesenchyme and od ectomes (fibromyxoma and cementoblastoma)

Malignant
- Od carcinomas (malignant ameloblastoma and ameloblastic carcinoma)
- Odontogenic sarcomas (ameloblastic fibrosarcoma)
- Od carcinosarcoma

Question 2

Ameloblastoma

Answer 2

Rare, non cancerous tumour that develops most often int the jaw near the molars.

Question 3

Odontoma

Answer 3

Tumour, benign
Require surgical removal
made up of dental hard tissue that resembles abnormal teeth or calcified mass that invade around your teeth and could affect how your teeth develop

Question 4

aetiology ameloblastoma

Answer 4

injury to mouth/jaw, infections of the teeth/gums
infections by viruses or lack of protein or minerals

Question 5

development of ameloblastoma

Answer 5

arises of Od epithelium
epithelium has marked proliferative capacity
grows by epithelial proliferation, extends between trabeculae of bone

Question 6

Ameloblastic fibroma

Answer 6

rare
younger pts
uni/multilocular

Question 7

Epidemiology ameloblastoma

Answer 7

commonest odontogenic tumour
rare under 10yrs
peak around 30-60 yrs
M=F
80% near in mandible near angle

Question 8

clinical presentation ameloblastoma

Answer 8

not site specific
incidental finding

Question 9

radiological features ameloblastoma

Answer 9

large
radiolucent
multilocular
expand bone, displace and resorb bone teeth
often destroys lower border of mandible

Question 10

histological feature ameloblastoma

Answer 10

ameloblastoma
- strands and islands of epithelial cells
- tall columnar cells at periphery
- loosely packed smaller central cells resembling stellate reticulum

ameloblastic fibroma
- solid tumour
- predominately mesenchymal, ameloblasta-like epithelium as less component
- no calcification of matrix
- hard tissue is present

Question 11

management of ameloblastoma

Answer 11

requires resection at least 15mm beyond radiological margins
recurrence inevitable if removal incomplete
annual follow up 5yrs then 3yrs thereafter
benign but up to 5% registered as death due to tumour
malignant transformation rate

Question 12

Aetiology of odontome

Answer 12

local trauma
infammatory
infectious processes
hereditary anomalies such as Gardener’s Syndrome and Hermanns Syndrome
odontoblastic hyperactivity
mature odontoblasts
dental lamina remnants (cell rests of serres)

Question 13

development of odontome

Answer 13

bulk formed by dentine
areas of active odontogenesis, reduced enamel epithelium and pulp may be present

Question 14

CEOT

Answer 14

Calcifying epithelial odontogenic tumour
rare
older patients
pre-molar, molar region
multilocular

Question 15

AOT

Answer 15

Adenomatoid Odontogenic Tumour (AOT)
rare
younger pts
maxilla
anterior to molar region
unilocular
speckled calcification
associated with U/E tooth

Question 16

CCOT

Answer 16

Calcifying cystic odontogenic tumour
rare
younger pts
either jaw
anterior to molar region
unilocular
large
varying calcification
associated with U/E tooth

Question 17

CB

Answer 17

Benign cementoblastoma
young females predominately 15-30yrs
well defined speckled radiopaque mass attached to root mandibular molar or premolar tooth
peripheral radiolucent zone
resorption of tooth root

Question 18

CF

Answer 18

Cemento-ossifying fibroma
young adults
F>M
Well defined radiolucent mass in mandible near roots of teeth
cellular fibrous tissue with calcified bone/cementum
benign tumour

Question 19

Epidemiology odontome

Answer 19

70% tumours
young patients
F>M
Maxilla>Mandible
Gardener’s syndrome

Question 20

Radiological features of odontomes

Answer 20

speckled/dense radiopacity with radiolucent areas
circumscribed mass, well-defined periphery
may displace adjacent teeth

Question 21

histological CEOT

Answer 21

sheets and islands of pleomorphic and hyperchromatic epithelium
amyloid accumulation with epithelial groups
calcification of amyloid material

Question 22

histological AOT

Answer 22

tubular structures of ameloblast-like epithelium
sheets of cuboidal/spindle epithelial cells
calcification of intratubular secretions

Question 23

histological CCOT

Answer 23

Ameloblastic like epi
calcification of ghost cells
irregular dentine may be produced

Question 24

histological CB

Answer 24

mass of cementum resembling pagetic bone
pleomorphic cementoblasts
unmineralised osteo-cementum at border

Question 25

management of odontomes

Answer 25

enucleation
gardener’s syndrome
- multiple odontomas
- supernumerary
- shortened/deformed roots