2- benign tumors of the jaw

benign tumors are usually what shape

round/oval

benign tumors usually have what kind of periphery/margins

Well-defined

▪ Smooth, regular

▪ Mostly corticated

benign tumors usually have what kind of density + internal architecture

Radiolucent or mixed

▪ radiopaque flecks seen in mixed

lesions

▪ Septations, loculations

(multilocular lesions)

benign tumors usually have what kind of effect on surrounding structures

• expansion + thinning of cortical bone, erosion (aggressive benign lesions)

• displacement of max sinus floor, IAN canal, teeth w/ external root resorption

3 types of odontogenic tumors

1. epithelial

2. ectomesenchymal

3. mixed

3 types of epithelial odontogenic tumors

1. ameloblastoma

2. adenomatoid odontogenic

3. calcifying epithelial odontogenic

what’s the most common epithelial odontogenic tumor

ameloblastomas (2nd most common odontogenic tumor overall)

3 patterns of ameloblastomas

1. conventional (75-86%)

2. unicystic (13-21%)

3. peripheral (1-4%)

ameloblastomas affect max or mand more

mand, usually in molar region

T/F: ameloblastomas are painful

false, often painless

radiographic features of ameloblastomas

1. well circumscribed/corticated

2. radiloucent

3. unilocular/multilocular (course + curved septae if multi)

4. may arise in cyst wall

describe what’s occurring in this radiograph

• pericoronal/mural; impacted tooth

• displacement of #32 + IAN

• osseous expansion

• thinning of cortices

describe the ameloblastoma in this radiograph

• multilocular w/ coarse septae

• thinning of inferior mand border

• displacement of teeth + IAN

follicular pattern hisopath features of ameloblastomas

• nests of epithelium

• island centers resembling stellate reticulum

• peripheral columnar cells with nuclei polarized opposite basement membrane (sub-nuclear vacuolization)

• mature fibrous background

desmoplastic pattern hisopath features of ameloblastomas

compressed islands + cords of odontogenic epithelium in densely collagenized stroma, presents in anterior max

2 tx options for ameloblastomas

1. simple enucleation (recurrence rate = 50-90%)

2. en bloc resection (recurrence rate = 15%)

unicystic ameloblastomas affects which age mostly

50% diagnosed between ages 10-20, associated w/ impacted 3rd molars

unicystic ameloblastomas often mimics what

dentigerous cyst

3 histopath types of unicystic ameloblastomas

1. luminal: confined to luminal surface

2. intraluminal: tumor nodules project from lining into lumen

3. mural: tumor islands in wall of cyst

tx options for unicystic ameloblastomas

1. luminal + intraluminal types treated w/ enucleation

2. mural type tx debatable

3. recurrence = 10-20%

T/F: peripheral ameloblastomas are soft tissue lesions only

true

peripheral ameloblastomas affects max or mand more

mand

peripheral ameloblastomas affect which age group

average age = 52

histopath features of peripheral ameloblastomas

1. epithelial islands beneath surface epithelium

2. plexiform and follicular patterns most common

3. 50% show connection to basal layer of surface epithelium

tx options for peripheral ameloblastomas

local excision w/ 15-20% reoccurrence

adenomatoid odontogenic tumors affect which age group

70% 10-20 years

adenomatoid odontogenic tumors commonly affect what area

max anterior

adenomatoid odontogenic tumors affect which gender more

women

radiographic features of adenomatoid odontogenic tumors

1. associated w/ unerupted tooth (commonly max lateral incisor)

2. mixed radiodensity: mostly radiolucent w/ some radiopacity within

3. displacement of adjacent teeth

histopath features of adenomatoid odontogenic tumors

1. well-defined lesion surrounded by thick fibroud capsule

2. tubular or duct-like structures

tx options for adenomatoid odontogenic tumors

enucleation

which type of epithelial odontogenic tumor is the most rare

calcifying epithelial odontogenic (Pindborg) tumors

radiographic features of calcifying epithelial odontogenic (Pindborg) tumors

1. mixed density- central radiolucency with radiopaque foci

2. maybe associated w/ unerupted tooth

3. expansile- expands cortex

4. root resorption possible

T/F: you can see B/L expansion in this radiograph

false, since this PAN is a superimposed image- you cannot tell

histopath features of calcifying epithelial odontogenic (Pindborg) tumors

1. islands, strands, or sheets of epithelial cells in fibrous stroma

2. Liesegang rings

tx options for calcifying epithelial odontogenic (Pindborg) tumors

conservative resection

2 types of ectomesenchymal odontogenic tumors

1. odontogenic myxoma

2. cementoblastoma

odontogenic myxomas usually affects which age

25-30

T/F: odontogenic myxomas are painless

true, small lesions are symptomatic + larger lesions are painless swelling

radiographic features of odontogenic myxomas

1. variable margins: well or poor defined

2. radiolucent

3. straight + thin septae

histopath features of odontogenic myxomas

1. loose stroma w/ collagen fibrils

2. haphazardly arranged stellate, spindle-shaped, round cells

tx options for odontogenic myxomas

1. small lesions are curetted

2. large lesions are resected

3. 25% recurrence + egg-white consistency makes complete removal difficult

cementoblastomas usually affect which age

pts younger than 20

T/F: cementoblastomas are painless

false, 67% report pain + swelling

radiographic features of cementoblastomas

1. multiple punctate radiopacities within a well-defined radiolucency

2. homogeneous radiopaque mass

3. mass attached to 1st mandibular molar roots

4. obscured root outline, external resorption

5. radiolucent halo - continuity w/ PDL

6. sclerotic border

differentiate cementoblastomas vs. hypercementosis

• cementoblastomas: globular

• hypercementosis: bulbous, more tooth-shaped

histopath features of cementoblastomas

1. trabeulae lined w/ plump cementoblasts

2. vascular CT

tx options for cementoblastomas

1. EXT of tooth w/ calcified mass

2. excision of mass w/ root amputation + endo tx

what’s the #1 most common odontogenic tumor/hamartoma

odontoma (74% of odontogenic tumors in US)

odontomas are made of

enamel, dentin, pulp, and/or cementum

3 types of odontomas

1. compound

2. complex

3. compound-complex

radiographic features of compound odontomas

1. radiolucent band/soft tissue capsule inside the cortical border

2. internal content is largely radiopaque: made of tooth-like structures called denticles

3. maybe associated w/ unerupted tooth

radiographic features of complex odontomas

1. radiolucent band/soft tissue capsule inside the cortical border

2. internal content is largely radiopaque- made of irregular mass of calcified tissue

radiographic features of compound-complex odontomas

1. mixed density, corticated

2. combination of amorphous radiopaque mass + tooth-like structures

histopath features of compound odontomas

multiple structures resemble small teeth in loose fibrous matrix

histopath features of complex odontomas

1. mature tubular dentin with structures that contained enamel before decalcification

2. 20% show ghost cells

3. thin layer of cementum around mass

tx options for odontomas

conservative enucleation

4 types of non-odontogenic tumors

1. osteoma

2. neurofibroma

3. vascular malformation (hemangioma)

4. giant cell lesions

radiographic features of osteomas

1. internal structure- uniformly radiopaque or internal trabecular structure

2. maybe be exophytic (projects outward), extending into adjacent soft tissues

why is the osteoma radiolucent

b/c it’s affecting more cancellous bone

T/F: osteomas only affect cancellous bone

false, can affect cortical bone too

histopath features of osteomas

compact lamellar bone w/ fibrofatty marrow, similar to tori + exostoses

syndrome associated w/ osteomas

Gardner’s syndrome: multiple osteomas + unerupted supernumerary/permanent teeth

Gardner’s syndrome has potential of malignancy for what

polyps in GI tract

radiographic features of neurofibromas

1. radiolucent

2. unilocular/multilocular

3. fusiform enlargement of the neurovascular canal

radiographic features of central vascular malformations (hemangiomas)

1. well defined, corticated or ill defined periphery possible

2. radiolucent

3. periosteal rxn (sunray-like appearance)

4. maybe multilocular

5. honeycomb pattern

6. displacement of teeth/root resorption

histopath features of central vascular malformations (hemangiomas)

proliferation of capillaries + endothelial cells containing abundant blood

2 types of bone hyperplasias

1. exostosis/tori: surface growth

2. enostosis (dense bone island): internal growth

2 types of exostosis/tori

1. torus palatinus

2. torus mandibularis

radiographic features of torus palatinus

1. dense radiopaque shadow attached to the hard palate

2. well-defined periphery, may have convex or lobulated outline

3. maybe superimposed over roots of teeth

radiographic features of torus mandibularis

1. hyperostosis that protrudes from lingual aspect of mandibular alveolar process

2. premolar area, bilaterally

3. radiopaque shadow w/ defined borders superimposed over roots of teeth

radiographic features of enostosis (dense bone island)

1. well-defined periphery but may blend w/ trabeculae of surrounding bone

2. no effect on teeth but rarely associated w/ root resorption

3. similar opacity as cortical bone

4 types of giant cell lesions

1. central giant cell granulomas (CGCG)

2. cherubism

3. brown tumors of hyperparathyroidism

4. aneurysmal bone cysts

central giant cell granulomas (CGCG) usually affects which age

younger than 20

clinical signs of central giant cell granulomas (CGCG)

1. asympomatic, swelling if lesion is on boen surface

2. tenderness on palpation, occasionally pain

3. sometimes overlying mucosa is purple

radiographic features of central giant cell granulomas (CGCG)

1. well defined periphery, not corticated generally

2. radiolucent: small lesions

3. internally: subtle granular calcifications, thin wispy septae

4. if adjacent to teeth: absence of lamina dura

histopath features of central giant cell granulomas (CGCG)

1. multi-nucleated giant cells

2. background of ovoid-spindle shaped mesenchymal cells

tx options for central giant cell granulomas (CGCG)

1. thorough curettage

2. aggressive tumors may be treated w/ corticosteroids, calcitonin, interferon-alpha-2a

what’s cherubism

familial fibrous dysplasia of the jaws: bilateral swellings at mand angles

clinical signs of cherubism

1. early childhood

2. chubby face

3. firm on palation, painless, normal mucosa

4. stops growing + regresses w/ age

radiographic features of cherubism

1. bilateral multilocular radiolucencies

2. multicystic appearance

3. expansion/thinning of cortices

4. uncommon perforation

5. tooth displacement, resorption

histopath feature of cherubism

eosinophilic cuffing (pink areas around purple), deposits around periphery of blood vessels

tx option for cherubism

intervention post puberty, usually no tx