cysts and cyst like lesions of the jaw

lecture given 4/30/2026- i tried to include all pics so sorry if this is the most annoying knowt ever

what are the keys to radiographic interpretation?

clinical exam, quality of the diagnostic images, number and type of diagnostic images, viewing conditions, image analysis

what factors should you use to systematically analyze intraosseous lesions?

location of the abnormality, periphery of the lesion and internal contents, effects on surrounding structures, radiographic interpretation

what are the types of acquired abnormalities?

cyst, benign neoplasia, malignant neoplasia, inflammatory lesion, bone dysplasia, vascular anomaly, metabolic disease, trauma

cyst

a pathologic cavity that is filled with fluid, lined by epithelium, and surrounded by definite connective tissue wall

development requires presence of epithelium in deep tissues and proliferative stimulus

what differentiates a pseudocyst from a cyst?

it lacks epithelial lining

what is the pathology of a cyst?

exact pathogenesis remains somewhat unknown

theories regarding that factors that influence formation and growth

exact mechanism is likely a combination of developmental and inflammatory influences unique to the cyst

what are the clinical features of a cyst?

swelling, lack of pain unless infected, interruption in the eruption of teeth

what are radiographic features of cysts?

located in mandible or maxilla

well defined and corticate if infected

round or oval

internal structure is radiolucent, can have dystrophic calcification and septation

what effects can cysts have on surrounding structures?

displacement, resorption of roots, expansion of cortical plates, IAC displacement (inferiorly), displacement of maxillary antrum

what is this?

cyst

types of odontogenic cyst

radicular, residual, dentigerous, buccal bifurcation, keratocystic odontogenic tumor, basal cell nevus syndrome, lateral periodontal, glandular odontogenic

types of nonodontogenic cysts

nasopalatine duct cyst, nasolabial

cyst like lesion

simple bone cavity, stafne defect

radicular cyst

most likely due to epithelial cells undergoing proliferations and degeneration due to inflammation

synonyms: periapical cyst, apical periodontal cyst, dental cyst

what are clinical features of radicular cysts?

*most common type of cyst in the jaw, arise from non-vital teeth

can be asymptomatic unless secondarily infected

incidence is greater in pts 30-60 y/o, shows a slight male predominance

60% found in maxilla, esp incisors and canines

what are the radiographic features of radicular cysts?

the periphery usually has a well defined cortical border- but if secondarily infected may lose cortex

typically radiolucent- dystrophic calcification may develop in long standing cysts

displacement and resorption of roots may occur

typical hydraulic (circular) shape in the periapical region of the tooth

what is this, and what is the pink arrow pointing at?

radicular cyst

the likely reason for the lesion (okay dr. seuss)

what is this?

radicular cyst

what is this, and what is happening?

radicular cyst

elevation of the maxillary antrum

what is this, and what is happening?

radicular cyst

blunting of roots and splaying of teeth

what is this and what phenomena can be seen in the lower row?

radicular cyst

partial volume averaging

what is this?

a baby with a radicular cyst

what are the differential diagnoses for a radicular cyst?

apical granuloma/abscess

fibrous healing of endodontically treated tooth (clinical evaluation may help differentiate)

early stage of periapical osseous dysplasia (vitality testing may help differentiate)

lateral periodontal cyst (vitality testing may help differentiate)

OKC if small and unilocular

how are radicular cysts managed?

vitality testing, CBCT if very large or encroaches on adjacent structures, removing the source of infection (endo or extraction)

if there is healing within a radicular cyst after it is treated, where does the healing start?

in the periphery, then fills in the center

what are the clinical features of a residual cyst?

inflammatory odontogenic cyst formed after incomplete removal of original radicular cyst following tooth extraction

more common in males

unilocular, round, well corticated radiolucency

maxilla more common than mandible

above IAC in posterior mandible

can extend into maxillary sinus

usually asymptomatic- asymptomatic tend to decrease in size due to epithelial atrophy, enlargement due to persistent presence of an inflammatory stimulus

symptomatic more common in anterior maxilla, and may be less corticated

*seen at edenulous spaces

what is this?

residual cyst

what are these?

residual cysts

what is this?

residual cyst

what are the differential diagnoses for residual cysts?

OKC- esp in the maxilla where expansion can be more hydraulic and uniform as opposted to anterio-posterior expansion pattern in mandible, residual cyst has more potential for expansion, OKC is more common in 20-30 y/o and in the posterior body of the mandible

stafne defect- will not grow (static), can occur below IAC

dentigerous cyst

second most common type of cyst in the jaws, associated with the crown of an unerupted tooth

synonyms: follicular cyst

what are the clinical features of dentigerous cysts?

missing tooth, swelling, facial asymmetry, painless unless secondarily infected

what is the location of dentigerous cysts?

most commonly 3rd molars or maxillary canines (supernumeraries, esp mesiodens)

*attaches at the CEJ

can grow to side of the crown rather than directly above it (lateral dentigerous cyst)

maxillary 3rd molar dentigenous cysts can grow into the antra and mandibular ones can extend considerably into the ramus

what are radiographic features of dentigerous cysts?

*epicenter is jsut above the crown of the impacted tooth

well defined, corticated unless infected

radiolucent with the crown within the lesion

displaces and resorbs teeth, can expand cortical boundaries, IAC displacement (usually inferior), can encroach into the maxillary sinus

what is this?

dentigerous cyst

what is this?

dentigerous cyst

what is this?

dentigerous cyst

what is this?

dentigerous cyst

what is this?

dentigerous cyst

what are the differential diagnoses for dentigerous cysts?

normal folluclar space (2-3mm), follicular hyperplasia (3-5mm)

odontogenic keratocyst- tends to not enlarge as much as dentigerous cysts

ameolblastic fibroma

unicystic ameloblastoma

adenomatoid odontogenic tumor- uncommon, may have internal calcifications

radicular cysts of primary tooth- can appear in similar pericoronal position in regards to developing permanent tooth

how are dentigerous cysts managed?

yank that tooth

buccal bifurcation cyst

molar may be missing, or have abnormally protruding lingual cusps through the mucosa

*tipping of occlusal table is a key diagnostic feature

1st molar > 2nd molar, rare in maxilla

vital teeth

may have firm buccal swelling

age range of first 2 decades

what are radiographic features of buccal bifurcation cysts?

PDL and lamina dura intact

occasionally bilateral

radiolucent

tipping of the involved molar- root tips are pushed into the lingual cortical plate of the mandible

is large enough it can displace and resorb adjacent teeth and cause a considerable amount of smooth expansion of the buccal cortical plate

if the cyst is secondarily infected, the periosteal new bone formation is seen on the buccal cortex adjacent to the involved tooth

what is this and what is A pointing to?

buccal bifurcation cysts

lingual cortical plate

what is this?

buccal bifurcation cyst

what is this?

buccal bifurcation cyst

what is this?

buccal bifurcation cysts

odontogenic keratocyst

10% of all cystic jaw lesions

occurs at any age and at all locations

asymptomatic unless secondarily infected

*high recurrence rate due to small satellite cysts or residual epithelium left after removal

aspirations may reveal a thick, yellow, cheesy material (keratin)

what are the radiographic features of odontogenic keratocyst?

located in posterior body of the mandible

well defined unless secondarily infected

corticated, smooth, round/oval shaped or scalloping outline

mostly radiolucent, with occasional radiopacities seen, internal septa

what is this?

odontogenic keratocyst

what is this?

odontogenic keratocyst

what is this?

odontogenic keratocyst

how are odontogenic keratocysts managed?

high recurrence rate- resection, curettage, or marsupialization (basically drain it but suture it so it has a permanent hole in it, don’t look it up)

periodic post-treatment clinically and radiographic examinations to detect any recurrence is recommended

typically every 6 months for first year and then yearly for the next 10 years

*basal cell nevus syndrome

aka gorlin-goltz syndrome, nevoid basal cell carcinoma syndrome

*inherited autosomal dominant

starts to appear early in life, usually after 5 y/o and before 30

what are clinical features of basal cell nevus syndrome?

OKC’s appear in multiple quadrants and earlier in life than solitary OKCs

high recurrence rate

skin lesions- small, flattened, flesh colored or brown papules occurring anywhere on the body but especially prominent on the face/neck/trunk

skeletal anomalies include bifid rib (most common)

calcification of the falx cerebri

what is the differential diagnosis for basal cell nevus syndrome?

cherubism

what are common characteristics (not all dental) of patients with basal cell nevus syndrome?

skin growths, jaw cysts, elevated scapula, chest/pectus deformity, enlarged head circumference, syndactyly, pitting of soles/palms, spine misalignment

what’s going on here?

calcified falx cerebri- potentially basal cell nevus syndrome

what is this?

basal cell nevus syndrome

lateral periodontal cyst

usually asymptomatic and less than 1cm in diameter

no sex or age predilection

vital tooth

if these cysts become secondarily infected, they mimic a lateral periodontal abscess

what are the radiographic features of lateral periodontal cysts?

50-75% in mandible

<1cm with round/teardrop shape

well defined radiolucency with a prominent cortical boundary and a round or oval shape

internal aspect is radiolucent

small cysts may efface the lamina dura of the adjacent root

large cysts can displace adjacent teeth

large cysts have similar growth pattern to OKC (minimum expansion)

how are lateral periodontal cysts managed?

excision

what is this?

lateral periodontal cyst

what are these?

lateral periodontal cysts

what are the differential diagnoses for lateral periodontal cysts?

small odontogenic keratocyst- OKC may have a more aggressive pattern of enlargement

simple bone cysts- scalloped between roots

lateral radicular cyst- non-vital tooth

small neurofibroma

mental foramen

glandular odontogenic cyst

cyst derived from odontogenic epithelium with characteristics of salivary gland features- mucus producing

aka sialo-odontogenic cyst

aggressive behvaior with recurrence

what are the radiographic features of glandular odontogenic cyst?

most common in anterior mandible and in maxilla

usually a cortical border that may be smooth or scalloped

both unilocular and multilocular appearances of this cyst have been reported

expansion of the outer cortical plates of the jaws with regions of perforation through the cortex has been reported

displacement of teeth is a common feature

what is this?

lateral peridontal cyst

what is this?

glandular odontogenic cyst

what is this?

glandular odontogenic cyst

what is this?

glandular odontogenic cyst

what is this?

glandular odontogenic cyst

what are the differential diagnoses for glandular odontogenic cyst?

ameloblastoma

OKC- younger age group

CGCG- younger age group

central mucoepidermoid carcinomas

how are glandular odontogenic cysts managed?

high rate of recurrence; aggressive treatment, including resection may be considered

follow up with periodic radiographic examinations to assess for recurrence

nasopalatine duct cysts

well defined, corticated, and is circular or oval in shape

shadow of the nasal spine may superimpose on the cyst, giving it a heart shape

usually totally translucent- rarely may have internal dystrophic calcifications, which may appear as ill-defined, amorphous, scattered radiopacities

PDL and lamina dura intact, rare for root resorption or root displacement

the cyst may expand in to the labial cortext and the palatal cortex

the floor of the nasal fossa may be displaced in a superior direction

what is this?

nasopalatine duct cyst

what are the differential diagnoses for nasopalatine duct cyst?

large nasopalatine fossa/foramen- typically non corticated, compare with prior or future images

periapical or residual cyst- non vital teeth

CGCG- younger age group, more common in mandible

dentigerous cyst of impacted mesiodens

adenomatoid odontogenic tumor

what is this?

nasoplalatine duct cyst

what is this?

nasopalatine duct cyst

what is this?

nasopalatine duct cyst

what is the management of nasopalatine duct cyst?

enucleation, preferably from the palate to avoid the nasopalatine nerve and biopsy

recurrence 2%, paresthesia <10%

if undertain as to if there is a cyst, can make serial radiographs in ~6 mo to assess for enlargement

nasolabial cyst

aka nasoalveolar cyst

unknown origin

unilateral swelling of the nasolabial fold, pain, or discomfort may be there

soft tissue cyst

what are radiographic features of nasolabial cysts?

soft tissue lesions seen apical to incisors, best modalities to image are CT or MRI

circular or oval with peripheral enhancement with contrast

homogenous in relation to the surrounding soft tissue

can cause erosion of the underlying bone

what are the differential diagnoses of nasolabial cysts?

nasal furuncle, mucous extravasation cyst or cystic salivary adenoma

what is this?

nasolabial cyst

what is this?

nasolabial cyst

simple bone cavity

no epithelial lining- not a true cyst

>males ~17, >females ~42 w pain or tenderness

*w > cemento-osseous dysplasia

aka traumatic bone cyst, hemorrhagic bone cyst, solitary bone cyst

what are imaging features of simple bone cavity?

borders vary from a well defined, delicate cortext to an ill-defined border without a cortext that blends into the surrounding bone

the shape most often is smooth and curved, similar to a cyst, with an oval or scalloped border

internal structure is radiolucent

it may appear multilocular although the lesion does not usually contain true septa

*no effect on surrounding teeth!

lamina dura intact or only partially disrupted

SBCs also have a tendency to grow along the long axis of the bone, causing minimal expansion

what is this?

simple bone cavity

what is this?

simple bone cavity

what is this?

simple bone cavity

what are the differential diagnoses of a simple bone cavity?

odontogenic keratocyst- resorbs and displaces teeth

diagnosis primarily relies on radiographic and surgical observations- at biopsy usually open lesion to reveal hollow non-lined cavity

what is the management of simple bone cavity?

a conservative opening into the lesion and careful curettage of the lining- this usually initiates bleeding and subsequential healing

spontaneous healing has been reported

periodic radiographic examinations are advisable, esp if the pt declines treatment

these lesions can recur but rare

what is this?

stafne defect

what is this?

stafne defect