Odontogenic Cysts Flashcards
What is the most common cyst of the jaws?
periapical cyst
What is the only odontogenic cyst that is inflammatory in origin?
periapical cyst
all the rest are developmental in origin
A periapical cyst develops due to inflammatory stimulation of __.
epithelial rests of Malassez
What are the signs and symptoms of a periapical cyst?
- asymptomatic
- associated with a non-vital tooth
- round/ovoid radiolucency at the apex
- inflammation through lateral canals may lead to lateral radicular cyst
Describe the histology of a periapical cyst.
inflamed granulation tissue or fibrous connective tissue lined by non-keratinized stratified squamous epithelium
What is the treatment for a periapical cyst?
endodontic therapy +/- apicoectomy or extraction with curettage
What is the prognosis of a periapical cyst?
- excellent
- routine follow-up is warranted (if tooth is removed, lesion may occasionally persist to form residual periapical cyst)
What is the most common developmental odontogenic cyst?
dentigerous cyst
How does a dentigerous cyst form?
fluid accumulates between the crown of the tooth and the reduced enamel epithelium (increased osmotic pressure) leading to gradual enlargement of the cyst
*note: subsequent infection and inflammation can occur
What are the signs and symptoms of a dentigerous cyst?
- by definition, associated with the crown of an unerupted tooth
- > 3-4 mm lucent space around crown to be considered dentigerous cyst
- symptoms usually absent, unless secondarily infected
- may produce swelling or resorption of the adjacent tooth roots
*note: radiographic findings are mimics by many odontogenic cysts and tumors
What is the most common site for dentigerous cyst? Age?
- mandibular 3rd molars, maxillary canines, maxillary 3rd molars
- 2nd or 3rd decades
Describe the histology of dentigerous cysts.
- uninflamed connective tissue lined by a thin non-keratinized stratified squamous epithelium
- some will have a few scattered mucous cells in the lining
What is the recommended treatment for a dentigerous cyst? Prognosis?
- removal of tooth and enucleation of the cyst; decompression of large cysts
- microscopic exam of lesional tissue to rule out OKC, ameloblastoma, other odontogenic cysts/tumors, or (rarely) central mucoepidermoid carcinoma
- excellent prognosis
What is an eruption cyst?
dentigerous cyst that forms in the soft tissue overlying the crown of an erupting tooth
What are the signs and symptoms of an eruption cyst? Who is most susceptible?
- bluish swelling common (thus the term “eruption hematoma”
- children
What is the treatment for an eruption cyst?
- take a radiograph to ensure tooth is erupting properly
- can lance cyst and drain it to allow the tooth to erupt more quickly
How common is a primordial cyst?
rare
How does a primordial cyst form?
- degenerating tooth bud epithelium
- forms in place of a tooth, before any mineralized material is deposited
What are the signs and symptoms of a primordial cyst?
- clinical and radiographic diagnosis based on no history of extraction or surgery in the area
- may arise from any tooth in the dentition
- usually detected as a unilocular radiolucency in the area of a missing tooth, usually a 3rd molar
Describe the histology of a primordial cyst.
same as odontogenic keratocysts
3 criteria:
- uniformly thin epithlial lining (stratified squamous, 6-8 cells thick)
- corrugated surface layer of parakeratin
- palisaded dark basal cell layer
- connective tissue wall is usually uninflamed (if inflammation present, histology of lining epithelium is markedly altered)
What is the treatment for a primordial cyst? Prognosis?
- TREATMENT: enucleation
- PROGNOSIS: good; with histo diagnosis of OKC, periodic radiograph follow-up for local recurrence is warranted
How common is an odontogenic keratocyst? Aggressive or non-aggressive?
- relatively common
- aggressive
With what syndrome is odontogenic keratocysts associated?
nevoid basal cell carcinoma syndrome
*note: suspected in patients
What is the most common age for odontogenic keratocysts?
3rd decade (but age ranges 6-80)
Which is more common (maxilla or mandible) for odontogenic keratocysts? What areas of each?
- mandible (2:1)
- posterior quadrants or ramus of the mandible
- anterior maxilla after age 60
What cysts resemble odontogenic keratocyst?
dentigerous cyst, residual cyst, lateral periodontal cyst
What are the signs and symptoms of an odontogenic keratocyst?
- asymptomatic, but may produce swelling/discomfort with enlargement
- 80% present as unilocular radiolucencies with well-demarcated margins and thin sclerotic border (larger lesions are multilocular)
Describe the histology of an odontogenic keratocyst.
3 criteria:
- uniformly thin epithlial lining (stratified squamous, 6-8 cells thick)
- corrugated surface layer of parakeratin
- palisaded dark basal cell layer (feature that we rely on most!)
- connective tissue wall is usually uninflamed (if inflammation present, histology of lining epithelium is markedly altered)
What is the treatment for an odontogenic keratocyst?
- SMALL LESION: careful enucleation as single piece
- LARGE LESION: decompression followed by enucleation
What is the prognosis for an odontogenic keratocyst?
- guarded
- recurrence rates range 3-62% (recent reports 40-50% in 5-years)
- patient follow-up for 7 years to detect recurrence
How is nevoid basal cell carcinoma syndrome acquired?
- PTCH gene, chromosome 9
- autosomal dominant, variable expressivity
- 40% new mutations
What are the signs and symptoms of nevoid basal cell carcinoma?
- enlarged occipitofrontal cranial circumference (60 cm or more in adults)
- heavy brow ridges
- broad nasal root
- mild ocular hypertelorism
- basal cell carcinomas that are multiple, in unexposed areas, develop at earlier age, have melanin pigment, and are usually quiescent
- shallow pits in the palms and/or soles (65%)
- milia and mutliple epideroid cysts (50%)
- lamellar calcification of the falx cerebri (85%)
- bifid, fused, or hypoplastic ribs (60%)
- odontogenic keratocysts (85%) at ages 7-10, probably multiple
What is the treatment for nevoid basal cell carcinoma syndrome?
- genetic counseling
- remove odontogenic keratocysts as needed
- remove basal cell carcinoma as needed
- use sunscreen and reduce sun exposure to decrease risk of basal cell carcinoma
What is the prognosis for nevoid basal cell carcinoma syndrome?
- guarded
- usually basal cell carcinomas are relatively small and indolent, but this can be variable
- periodic radiographic follow-up for odontogenic keratocysts
A gingival cyst of the newborn is a cyst of the ___.
dental lamina
Describe the appearance of a gingival cyst of the newborn.
- 1-2 mm yellow-white papules
- usually in the maxillary
Describe the histology of gingival cyst of the newborn.
- thin uniform stratified squamous epithelial lining
- cyst lumen is packed with keratin debris
What is the treatment for gingival cyst of the newborn?
none!
self-marsupialization and spontaneous involution
What are Epstein pearls? What are they related to?
- along the median palatal raphe; arise from epithelium entrapped along the line of fusion
- gingival cyst of the newborn
What are Bohn nodules? What are they related to?
- scattered over the hard palate, often near the soft palate junction; derived from minor salivary glands
- gingival cyst of the newborn
What cyst is related to the lateral periodontal cyst?
gingival cyst of the adult
How does the gingival cyst of the adult form?
arises from dental lamina rests (rests of Serres) in the gingival connective tissue
What age is most common for the gingival cyst of the adult? Gender? Location in oral cavity?
- adult over age 40
- no gender preference
- anterior segments of jaw (canine/premolar)
What are the signs and symptoms of the gingival cyst of the adult?
- smooth-surfaced dome-shaped elevation of the attached gingiva
- usually less than 1 cm in diameter
- tense on palpation, otherwise asymptomatic
- translucent or bluish
- minimal, if any, findings on radiograph
*note: may mimic mucocele but it is on attached gingiva and there are no salivary glands on attached gingiva
Describe the histology of the gingival cyst of the adult.
cystic cavity lined by thin uniform layer of cuboidal or attenuated non-keratinized stratified squamous epithelium
What is the treatment for the gingival cyst of the adult? Prognosis?
- TREATMENT: conservative excision
- PROGNOSIS: excellent
How does a lateral periodontal cyst occur?
occurs adjacent or lateral to the root of a tooth, arising from the intrabony rests of the dental lamina
What oral region is most common for a lateral periodontal cyst? What age range?
- mandibular premolar or maxillary lateral incisor
- 5th or 6th decades
True or false: The adjacent teeth to a lateral periodontal cyst are non-vital.
FALSE. They are vital!
What are the signs and symptoms of a lateral periodontal cyst?
- asymptomatic unilocular radiolucency lateral to vital tooth
- typically less than 1 cm in diameter
Describe the histology of a lateral periodontal cyst.
thin non-keratinized stratified squamous epithelium lining, uninflamed fibrous connective tissue
What is the recommended treatment of a lateral periodontal cyst? Prognosis?
- curettage
- excellent
What condition is also known as a Gorlin cyst?
calcifying odontogenic cyst
What are the signs and symptoms of a calcifying odontogenic cyst?
- well-defined unilocular radiolucency with scattered radiopacities in 50% of cases
- 5-17% reported in gingival soft tissues
- resorption of adjacent tooth roots common (80%)
With what are calcifying odontogenic cysts sometimes associated?
- impacted tooth (30%)
- odontoma (20%)
Describe the histology of calcifying odontogenic cysts.
- cystic with proliferation of odontogenic epithelial cells that (at the periphery) show cuboidal or columnar appearance of basal cells
- solid variants recognized
- as cells approach lumen, undergo process termed “ghost cell” change
- cells are pale and eosinophilic, with swollen cytoplasms and loss of the nucleus that exhibits a faint nuclear membrane outline
- traditionally described as aberrant keratinization, but some think its a form of coagulation necrosis
*note: cuboidal/columnar basal cell appearance similar to ameloblastoma
What is the treatment for calcifying odontogenic cysts? Prognosis?
- TREATMENT: enucleation with curettage
- PROGNOSIS: recurrence not common, but does occur so need follow-up
