Odontogenic Tumours Flashcards
are odontogenic tumours symptomatic
majority are asymptomatic
pain is usually secondary to infection or pathological fracture
what are the 3 tissues of origin for odontogenic tumours
epithelial
mesenchymal
mixed (epithelial and mesenchymal)
types of epithelial origin odontogenic tumours
ameloblastoma
adenomatoid odontogenic tumour
calcifiying epithelial odontogenic tumour
type of mesenchymal odontogenic tumour
odontogenic myxoma
type of mixed odontogenic tumours
odontoma
what are the 3 odontogenic sources of epithelium
- rests of malassez (remnants of HERS)
- rests/glands of serres (remnants of dental lamina)
- reduced enamel epithelium (remnants of enamel organ)
odontogenic tumour radiographic representation
highly variable
- appearance may change as lesion progresses
- some entirely radiolucent, some mixed, some entirely radiopaque
what are the 2 most common odontogenic tumours
ameloblastoma
odondotoma
ameloblastoma
- what is it
- symptoms
- incidence
- benign epithelial tumour
- typically painless
- most common in 30s-50s, in posterior mandible
radiographic features of ameloblastoma
- well defined corticated margins
- potentially scalloped
- primarily radiolucent
- ‘soap bubble appearance’ septae within lesion
- thinning of bony cortices
- adjacent structures may be displaced
- knife edge external root resorption
ameloblastoma pattern of growth
expands in all directions fairly equally
what are the 3 ways to classify ameloblastomas histologically
follicular
plexiform
desmoplastic (rare)
follicular ameloblastoma presentation
follicular = histological classification
islands present within a fibrous tissue background. Islands bordered by ameloblasts.
tissue in middle of follicles resembles stellate reticulum
plexiform ameloblastoma
plexiform = histological classification
ameloblast like cells arranged in strands, in between strands may stellate reticulum like tissue.
why do ameloblastomas have a high recurrence rate
no connective tissue capsule so can infiltrate surrounding jaw bone
ameloblastoma risk of malignancy
<1%
adenomatoid odontogenic tumour (AOT)
- what is it
- incidence/ epidemiology
- association
benign epithelial tumour
most common in teens, majority occur in anterior maxilla
majority of cases associated with unerupted tooth
differentiating between dentigerous cyst and adenomatoid odontogenic tumour
dentigerous cyst typically attaches at ECJ
AOT typically attaches apical to ECJ
radiographic presentation of adenomatoid odontogenic tumour
well defined, corticated margins,associated with an unerupted tooth
may displace adjacent structures
impedes eruption
margins join tooth apical to ECJ
most common tooth to be affected by an adenomatoid odontogenic tumour
maxillary canine
histological appearance of adenomatoid odontogenic tumour
well developed fibrous tissue capsule
epithelial cells may be arrances in duct like structures or in rosette like appearace.
flecks of radiopacity in radiographs correspond to patchy calcification
calcifying epithelial odontogenic tumour
benign epithelial tumour
presentation of calcifying epithelial odontogenic tumour
slow growing
50% associated with unerupted tooth
radiolucency with internal radiopacities
odontogenic myxoma
benign mesenchymal tumour
radiographic presentation of odontogenic myxoma
well defined radiolucency +/- thin corticated margin
scallops between teeth
soap bubble appearance
small lesions unilocular, large lesions multilocular
scallops between teeth
tennis racket appearance of internal septae may be present
odontogenic myxoma recurrence rate
high recurrence rate (25%)
Odontoma
benign mixed tumour
malformation of dental tissue (enamel, dentine, cementum and pulp)
what are the 2 main types of odontoma
compound
complex
compound odontoma
ordered dental structuresm more common in anterior maxilla
complex odontoma
disorganised mass of dental tissues
more common in posterior mandible
