Multilocular Radiolucencies

Question 1

Benign odontogenic neoplasm; one of very few true odontogenic neoplasms
Capable of uncontrolled, unlimited
growth potential

Answer 1

Ameloblastoma

Question 2

What are the 2 classifications of ameloblastoma?

Answer 2

1. Conventional (Multicystic) Ameloblastoma -> more common

2. Unicystic (Mural) Ameloblastoma

Question 3

• Account for 85 – 90% of all ameloblastomas

- type of subtypes determine how fast it grows

Answer 3

Conventional (Multicystic)

Ameloblastoma

Question 4

• Usually slow painless swellings
• Small lesions only detected by
radiographs
• Larger lesions detected clinically

Answer 4

Conventional ameloblastoma

Question 5

Radiographic
• Small lesions are 
unilocular with 
corticated borders
• Large, aggressive 
lesions develop 
multilocular patterns
• Displace and resorb 
teeth
• expansive
Age
-Mainly adults – equal prevalence in 3’rd to 7’th decade 
-Uncommon in 2’nd decade
-Rare in 1’st decade
Site
-mandible (85%); maxilla (15%) - mostly posterior mandible
Gender Predilection
-none 
Management
-Large lesions are aggressive requiring bone 
resection.
-Block or marginal resection; ie resect >1.0cm 
past radiographic limits of tumor
15% recurrence 
Other
-Higher likelihood for recurrence.
-50-90% recurrence if not resected
-Rare to be malignant

Answer 5

Conventional Ameloblastoma

Question 6

If there is a cyst that begins growing very large, what could be present in cyst?
Age
Mean age 23 years
Site
Mandible (90%)
Maxilla (10%)

Answer 6

Unicystic ameloblastoma

Question 7

Do you resect multicystic or unicystic ameloblastoma?

Answer 7

Multicystic

Question 8

Pathophysiology
• 10-12% of all odontogenic cysts; 3’rd 
highest oral cyst frequency
• aggressive cysts; behave more like 
benign neoplasms
• thought to arise from cell rests of dental 
lamina

Answer 8

Odontogenic Keratocyst

Question 9

Clinical
• Normally asymptomatic
• With increasing size, pain, swelling and 
exudate may occur
Radiographic
• Well-defined, smooth, 
corticated borders
• Thinning and mild 
expansion with 
occasional perforation  
of cortical plates
• Displacement of teeth 
• *only occasional 
root resorption
(< dentigerous and 
< radicular cysts)
• *mild B-Li 
expansion; but 
extensive antero-
posterior extension
Age
Majority (i.e., 60%) in 2nd and 4th decade
Site
Majority (60-80%) affect mandible posterior to the 
canines
Gender
Male predilection
Management
Enucleation with curettage
Other
• High recurrence rate;  some rates 
reported @ 47 and 62% (probably 
parakeratinized variants)
• When multiple are found they 
may constitute part of the basal cell 
nevus syndrome (a.k.a. nevoid basal 
cell carcinoma syndrome)

Answer 9

OKC

Question 10

• multiple basal CA’s of skin 
• Palmar and plantar pitting (60%)
• > 1 OKC (KOT) of jaws (75%)
• Bifid or splayed ribs (60-75%)
• Kyphoscoliosis (50%)
• Skull anomalies:
- frontal and parietal bossing
- hypertelorism
- intracranial calcifications;
- majority are of falx cerebri
Autosomal dominant

Answer 10

Nevoid basal cell carcinoma

Question 11

Clinical 
• Asymptomatic swelling
• Can be aggressive
Radiographic
• Well-defined 
borders
• Can be multilocular
• Thinning and 
expansion of cortical 
plates
• Displacement of 
teeth and occasional 
root resorption
Age
Usually < 30 years (60%)
Site
mandible (70%) & frequently between the 
molars
Gender
Female > male (2:1)
Management
Enucleation with aggressive curretage
Other
• Lesion is histologically similar to the Brown 
tumor of primary hyperparathyroidism
• Patients with the CGCG should be evaluated 
for this systemic disease with appropriate 
blood studies:  ie, increased serum calcium 
and alkaline phosphatase, decreased serum
phosphorus

Answer 11

Central Giant cell granuloma

Question 12

• Primarily a lesion of alveolar bone
• Basically a fibrous lesion
Radiographic:
-Scalloped and 
multilocular
Age
Young to adults (25 – 30 years)
Site
Greater prevalence in mandible
Management
Excision
Other
Recurrence up to 25% because the lesions are 
not encapsulated.

Answer 12

Odontogenic myxoma

Question 13

Clinical
• Jaws are next most common site after skull and
vertebrae
• Firm, slow-growing asymmetric expansion
• Overlying mucosa is more erythematous and warm to
touch
• Spontaneous gingival bleeding
• Bruit on diascopy and pulsatile sensation may be
detected
• Many require needle aspiration to assist diagnosis
Radiographic
• Variable pattern ranging from cyst-like radiolucencies
• May have multilocular “soap-bubble” or spoke-like appearance
Age
Teens and young adults
Site
Posterior mandible
Sex
Female:male 2:1
Management
• Sclerosing agents, radiation,
enucleation
• Embolization of major arteries
necessary prior to surgery as
hemorrhage is a significant and life-
threatening complication
Other
Etiology is either traumatic/developmental
or benign neoplasm

Answer 13

Central hemangioma

Question 14

Clinical
• Cherubic looking face by 5 years of age due
to bilateral bony expansion
• Asymptomatic
• Bone lesions are more active in younger
patients. After age 12, activity usually
diminishes and finally lesions become
inactive with residual deformity by age 30
Radiographic
• Bilateral multilocular cyst-like, expansile lesion, usually affecting the mandible and sometimes themaxilla
• Pathologic fracture is not a feature
Age
Usually detected by age 5
Site
Bilateral mandible, may affect maxilla
Sex
Male:female 2:1
Management
Cosmetic osseous contouring at age 12 and
later
Other
Benign self-limiting condition

Answer 14

Cherubism
a.k.a.
Familial Fibrous
Dysplasia