BDS4 Odontogenic Tumours Flashcards
describe odontogenic tumours?
- Majority asymptomatic
*Often discovered due to non-eruption of teeth, late-stage bony expansion or imaging for other reasons (i.e. incidental)
*Pain usually secondary to infection or pathological fracture - Mostly arise within the bone of the jaws
what is classification of odontogenic tumours? and example of each?
3 groups based on tissue origin
- epithelial - ameoblastoma
- mesenchymal - Odontogenic myxoma
- mixed (epithelium and mesenchyme) - odontoma
what can only mixed tumours have
dentine/enamel formation
what are odontogenic sources of epithelium?
- Rests of Malassez
*Remnants of Hertwig’s epithelial root sheath - Rests/glands of Serres
*Remnants of the dental lamina - Reduced enamel epithelium
*Remnants of the enamel organ
what are types of epithelial odontogenic tumours?
Ameloblastoma
Adenomatoid odontogenic tumour
Calcifying epithelial odontogenic tumour
what are most odontogenic tumours?
- > 50% of cases are either ameloblastoma or odontoma
what are radiograph appearences like of odontogenic tumours?
highly variable
* Entirely radiolucent mixed entirely radiopaque
what is an ameloblastoma? incidence
- Benign epithelial tumour
*Locally destructive but slow-growing
*Typically painless
incidence - 40-60
- posterior mandible and male
types of ameloblastoma?
Radiological
* Multicystic (85-90%)
* Unicystic
*Younger patients
*Lower recurrence risk
Histological
* Follicular
* Plexiform
* Desmoplastic
* (Several other less common types
what is this?
ameloblastoma
describe structure ameloblastoma?
- Margins
*Well-defined, corticated
*Potentially scalloped - Multicystic type
*May have thick, curved septa → “soap bubble” appearance - Primarily radiolucent (but rare variants can be mostly radiopaque)
- Adjacent structures
*Displacement
*Thinning of bony cortices
*“Knife edge” external root resorption
what is histology of follcular ameoloblastoma?
Ameloblast-like cells
Stellate reticulum like tissue
Cystic changes
Fibrous tissue
what is histology of plexiform ameloblastoma?
Ameloblast-like cells
Stellate reticulum like tissue
Fibrous tissue
what is management of ameloblastoma?
- Surgical resection with margin
- Recurrence relatively common
- Risk of malignant transformation
*<1% of cases
*Ameloblastic carcinoma
what is adenomatoid odontogenic tumour? incidence?
- Benign epithelial tumour
Unilocular radiolucency with internal calcifications around crown of unerupted maxillary canine” is classic presentation - incidence
-20s
-females more than males
-anterior maxilla
what is presentation of adenomatoid odontogenic tumour?
- 75% associated with unerupted tooth
-commonly upper canine - Unilocular radiolucency
- Majority have internal calcifications/radiopacities
- Margins well-defined & corticated/sclerotic
- May displace adjacent structures
what is histology of adenomatoid odontogenic tumour?
- distinctive with patchy calcification
- duct like structure
what is this
adenomatoid odontogenic tumour
what is Calcifying epithelial odontogenic tumour?
- Benign epithelial tumour
incidence
-50s
-males and posterior mandible
what is presentation of Calcifying epithelial odontogenic tumour?
- Slow-growing but can become large
- Half are associated with an unerupted tooth
- Radiolucency often with internal radiopacities
*Calcifications of varying sizes - Variable radiographic presentation otherwise
*Unilocular / multilocular
*Margins: well-defined / poorly-defined
*Internal septa: none / fine / coarse
what is odontogenic myxoma?
- Benign mesenchymal tumour
incidence
-30s
-females and males equal
-mandible more
what is Odontogenic myxoma presentation?
- Well-defined radiolucency +/- thin corticated margin
*Smaller lesions unilocular
*Larger lesions multilocular with scalloped margins
*“Soap bubble” appearance - Slow growth along bone before causing notable
bucco-lingual expansion - Scallops between teeth but larger lesions may
cause displacement
what is histology of Odontogenic myxoma?
- Loose myxoid tissue with stellate cells
- May contain islands of inactive
odontogenic epithelium - No capsule → locally invasive
what is management of Odontogenic myxoma?
- Curettage or resection (depending on size)
- High recurrence rate: 25%
*Follow-up important
*Lower recurrence rate if unilocular
what is odontoma? incidence
- Benign mixed “tumour”
*Technically a hamartoma
*Malformation of dental tissue - Similarities to teeth
**Mature to a certain stage (i.e. do not grow indefinitely)
**Can be associated with other odontogenic lesions (e.g. dentigerous cysts)
**Surrounded by dental follicle
**Lie above inferior alveolar canal
incidence - 20s
- females and males equal
what are types of odontoma?
- Compound odontoma
* Ordered dental structures
* May appear as multiple “mini teeth” (i.e. denticles)
* More common in anterior maxilla - Complex odontoma
* Disorganised mass of dental tissues
* More common in posterior body of mandible
what is this?
Calcifying epithelial odontogenic tumour (CEOT)
what is this?
Odontogenic myxoma
what is this?
odontoma
