60 terms

Unilocular Periapical Radiolucencies( RL)

Unilocular Periapical RL
Periapical Granuloma
Periapical Cyst
Periapical Cemento-osseous dysplasia (early lesion)
Periapical Granuloma
RL- unilocular
corticated or non-corticated (can be either)
Histology of Periapical granuloma
*inflamed granulation tissue surrounded by fibrous connective tissue wall
Cells involved in periapical granuloma
plasma cells
Periapical Cyst
Has epithelial lining
Most COMMON odontogenic cyst more than 50%
Either inflammatory or developmental
Loss of Lamina Dura at apex
*Non-vital tooth
DX: pulp testing, biopsy
TX: extraction or endo therapy
Differential DX for periapical cyst
periapical cyst and peripical granuloma always go together
Periapical Cemento-Osseous Dysplasia
Benign Bone Tumor
Site: Periapical of Mand. Anteriors
Most common in Middle aged black females
Radiographic findings of periapical cemento-osseous dysplasia
RL Early
Mixed RO Late

Dx: clinical and xray findings
Tx: none necessary
Unilocular Pericoronal Radiolucencies
Dental Follicle
Dentigerous Cyst
Eruption Cyst
Odontogenic keratocyst-OKC
Ameloblastic Fibroma
Adenomatoid Odontogenic Tumor- AOT
Dentigerous Cyst
Most Common DEVELOPMENTAL odontogenic cyst
Comes from reduced enamel epithelium
Always assoc. w/ the crown of an impacted tooth
Site: Mand. 3rd Molars
on xray, appears to meet tooth at CEJ commonly

Tx: Ext tooth and remove cystic tissue
Symptoms of Dentigerous Cyst
Tooth Displacement
Root Resorption
Eruption Cyst
Soft tissue component of dentigerous cyst
Looks like blood blister

Tx: allow tooth to erupt, cyst will resolve
Odontogenic Keratocyst (OKC)
Follows along border of mandible
Doesn't cause expansion
Site: posterior mandible
Can't tell the difference btwn this and dentigerous cyst

Assoc with Nevoid Basal Cell Ca Syndrome
Clinical Findings of Odontogenic Keratocyst (OKC)
Grow anterior-posterior direction
Minimal Bony Expansion
RL-well defined
uni or multilocular
"SOAP BUBBLE" appearance
May be corticated (smooth borders)
Impacted tooth 25-40% of lesions
Tx of OKC
Enucleation and curettage
(remove cyst)
Recurrence rate for OKC
30% at 5 year follow up
Follow up on lesions for at least 7 years post surgery to detect recurrences
Nevoid Basal Cell Cancer Syndrome
Autosomal dominant
40% are new mutations
caused by mutation in tumor suppressor cells
OKC are assoc with this syndrome
*basal cell carcinomas on skin
* odontogenic keratocysts in mouth
Not assoc with a tooth
Clinical Findings of Nevoid Basal Cell Ca Syndrome
Mult basal cell carcinomas on skin
85% ot pts have more than 1 odontogenic keratocusts
Intracranial calcifications
100% of pts have basal cell carcinomas
Things Assoc. with Impacted Teeth
Eruption Cyst
Dentigerous Cyst
Periapical Cyst
Ameloblastic Fibroma
Adenomatoid odontogenic tumor
Ameloblastic Fibroma
Site: Post. Mandible
Assoc with impacted tooth
Expansion and swelling present
Only seen in pts under 20 yrs
Most of the time Unilocular
Corticated rim
Appears multilocular but really unilocular
Differential DX:
Dentigerous Cyst
Ameloblastic Fibroma
Adenomatoid Odontogenic Tumor (AOT)
Arises from enamel organ or dental lamina (or both)
60% occur in kids age 10-19
Females more than Males
Maxilla more than Mandible
No recurrence
Tx: enucleation (ext and remove tumor)
Adenomatoid Odontogenic Tumor on Xray
Well-circumscribed RL
RL with RO flecks
Impacted tooth 75%
Unilocular Interradicular RL (btwn the roots)
Lateral radicular cyst
Nasopalatine Periodontal Cyst
Lateral Periodontal Cyst
Residual Cyst
Odontogenic keratocyst
Central Giant Cell Granuloma
Lateral Radicular Cyst
Located on side of root, not apex
Well defined RL-unilocular
Corticated or non-corticated
Dx: pulp testing, biopsy
Tx: EXT, or ENDO
*Non-Vital Tooth
Re-eval in 6 months and 1 yr.
Recurrence: Rare
Nasopalatine Duct Cyst
Unilocular RL
Will only occur btwn #8 and #9
Has a pear shape
Dx: biopsy
Tx: surgical removal

Symptoms: swelling of ant palate
possible drainage and pain
Lateral Periodontal Cyst
Arises along lateral root surface
Occurs in adults 40-50 yrs
Always assoc with a VITAL TOOTH
90% of time located Mand. canine/ premolar
Just in soft tissue, not in bone
Tx: curettage

Must do a vitality test
Xray appearance of Lateral Periodontal Cyst
Unilocular RL or Multilocular RL
May cause Rooth Divergence
Competely asymptomatic
Residual Cyst
Located in area where tooth once was
unilocular RL
corticated or non-corticated
Dx: biopsy plus extraction history
Tx: surgical removal
Recurrence unlikely
Simple Bone cyst
*Teeth are VITAL
20% of pts have painless swelling
Tends to Scallop btwn teeth
Empty or fluid filled cavity
No epithelial lining
Not a true cyst
Walls lined by thin band of fibrous connective tissue
may be vascular
TX: biopsy with curettage
Xray findings of Simple Bone Cyst
Well-defined RL lesion
Scallops btwn roots and teeth
Vital teeth with little to no root resorption
Multilocular RLs
Central Giant Cell Granuloma
Odontogenic Keratocyst
Myxoma (odontogenic myxoma)
Traumatic Bone Cyst
Odontogenic Myxoma
Young adults 25-30 yrs
Mandible more than maxilla
* Post. Mandible most common
May have some Expansion
If small lesion: asymptomatic
If large lesion: painless swelling
May displace teeth
May cause root resorption
Xray of Odontogenic Myxoma
Multilocular RL
"Soap Bubble" Appearance
Irregular scalloped margins
thin wispy trabeculae arranged at right angles
Odontogenic Myxoma Tx and prognosis
Tx: curettage
Resection of large lesions
Follow-up periodically

Prognosis: 25% recur

*these are aggressive and can come back
Most common on Mand. (can extend into ramus)
Can cause painless expansion
Usually grows in anterior-posterior direction
can also grow bucally-lingually
20% assoc with impacted tooth
Ameloblastoma on Xrays
small lesion: unilocular RL
large lesion: multilocular, "soap bubbles"
May have a honeycomb RL
Tx of Ameloblastoma
Depends on size of the lesion
*small: aggressive curettage or resection
*Large: resection or segmental resection

Central Giant Cell Granuloma
Ave Age: 30
Site: ant. or Post Mandible
Painless Expansile Lesion
Grows inside the bone
Xray findings of Central Giant Cell Granuloma
Well- defined RL
uni- or multilocular
*Most commonly multilocular
with or without corticated rim

Dx: Biopsy
Tx: curettage
corticosterois injections
Differential Dx for ameloblastoma
Lateral/Perio Cyst
Lateral Radicular Cyst

must biopsy
Autosomal Dominant
Age at Dx: 2-5 yrs, mild case 10-12 yrs
*Bilateral expansion of post mandible and ramus
also affects maxilla
Multilocular RL
Corticated lesions
Can continue to grow and cause expansion until sexual maturity; lesions then goes away

Tx: Observe
Vascular malformation
Posterior Mandible
-if in area of inf alv canal, it is inside the bone
uni- or multilocular
"worm hole" appearance
Tx; depends on lesion
Traumatic Bone Cyst
Age:10-20 yrs
Site: premolar/molar region
20% pts have painless swelling
XRAY of Traumatic Bone Cyst
Well-defined RL lesions
Scallops btwn roots of teeth
Vital teeth with NO root resorption
Poorly Defined RL
**Think Cancers**
Periapical granuloma or cyst
Malignant Tumors
*Primary cancers:
Squamous cell carinoma
Osteosarcoma (most common)
*Metastatic Cancers:
Focal Osteoporotic Bone Marrow Defect
One Spot...Radiolucent...larger collection of bone marrow
Site: Posterior Mandible
75% of cases are female
Usually follows extraction
Bone marrow fills in space instead of bone
Poorly defined RL
No sharply defined borders

Tx: biopsy
Biopsy shows:
*Normal hematopoietic marrow
*Normal Bone Trabeculae

no further treatment
xray findings of Osteoporotic Marrow Defect
Poorly defined borders
Fine central trabeculations
Overall RL appearance
Follow pt to observe
Eval with cone beam CT scan
Usually incidental finding
Metastatic Cancer
Most Common Malignancy Within Bone
More than 80% or cases occur in Mandible
Metastatic Cancer of jaw sites of Origin:
Symptoms of Metastatic Cancer in Jaw
Loosening of teeth
A Mass
Tissue proliferating out of an extraction site (very bad sign)
Mixed RO/RL Lesions
Cemento-osseous Dysplasia
Ameloblastic Fibro-odontoma
Calcifying Epithelial Odontogenic Tumor
Calcifying Odontogenic Cyst
Paget's Disease of Bone
Fibrous Dysplasia
Ameloblastic Fibro-Odontoma
Arises from odontogenic epithelium and CT
Only seen in kids under 15 yrs

20% recurrence
xray findings Ameloblastic Fibro-Odontoma
Uni- or multilocular
Impacted tooth
RO Flecks
Calcifying Epithelial Odontogenic Tumor
Age: 40 yrs
Mandible more common than maxilla
Asymptomatic or swelling

Tx: conservative excision
14% recurrence

***This occurs only in adults
otherwise indistinguishable from ameloblastic odontoma
Xray Findings of Calcifying Epithelial Odontogenic Tumor
Diffuse or well-circumscribed
RL or RL w/ radiopacities
*snowflake calcifications
50% Impacted tooth
Calcifying Odontogenic Cyst
Site: Mandible more common than maxilla
Looks like:
Calcifying epithelial odontogenic tumor &
ameloblastic fibro-odontoma
Xray findings of Calcifying Odontogenic Cyst
Unilocular RL with scattered radiopacities
30% assoc with impacted tooth
Can't tell difference btwn OKC(odontogenic keratocyst) and:
Dentigerous Cyst
Can't tell difference btwn Periapical granuloma and:
Periapical Cyst