Cysts of the Jaw Flashcards
definition of a cyst
pathological cavity with fluid, semi-fluid or gaseous contents which is not created by the accumulation of pus
signs and symptoms of a cyst (4)
- mobility of teeth
- bony swelling
- numbness (if pressing on a nerve)
- loss of vitality of teeth
- previously hard structure now feels like egg shell cracking when pressed , due to thinned bone
radiographic features of cysts
- shape
- margins
- locularity
- multiplicity
- usually spherical or egg shaped
- well defined corticated margins
- majority unilocular
- almost always singular
by what method do majority of cysts grow
hydrostatic pressure
(pressure exerted by fluid in a confined space)
what impact will infection have on a cyst
radiographically - loss of corticated margins and loss of definition
clinically - painful, fever, pus
what are the 3 ways cysts of the jaw can be classified
structure - epithelium lined or not
origin - odontogenic or non odontogenic
pathogenesis - developmental or inflammatory
what is the most common odontogenic cyst
radicular cyst
(residual)
name 2 developmental odontogenic cysts
dentigerous cyst
odontogenic keratocyst
(lateral periodontal cyst)
name an inflammatory odontogenic cyst
radicular cyst
(inflammatory collateral cysts)
name a developmental non odontogenic cyst
naso-palatine duct cyst
name 2 features that are always present in odontogenic cysts
- always lined with epithelium
- always above the IA canal
what are the 3 odontogenic sources of epithelium
- rests of mallasez (remnants of HERS)
- rests of Serres (remnants of dental lamina)
- reduced enamel epithelium (remnants of enamel organ)
what are radicular cysts always associated with
always associated with a non vital tooth - initiated by chronic inflammation at apex of tooth due to pulp necrosis
what age group do radicular cysts most commonly affect
40s/50s
what may a radicular cyst be confused with radiographically if small
periapical granuloma
radiographic appearance of a radicular cyst
- associated with a non vital tooth
- corticated cyst margins will be continuous with lamina dura of non-vital tooth
- large lesions may displace other structures
how does a radicular cyst form from a granuloma
epithelial rests of malassez proliferate in periapical granuloma
continued growth via cytokines and central necrosis sees transition to cyst
residual cyst
when a radicular cyst persists after loss of a tooth or after successful RCT
extraction of non vital tooth will not cure radicular cyst, cyst requires removal
dentigerous cyst
developmental cyst from reduced enamel epithelium associated with the crown of an unerupted tooth
radiographic appearance of a dentigerous cyst
associated with crown of an unerupted tooth - corticated margins will meet crown at ECJ
crown will be within cyst, tooth may be displaced
dentigerous cyst vs enlarged follicle
normal follicular space 2-3mm
consider cyst if follicular cyst >5mm, presume cyst if >10mm
(always consider cyst if radiolucency asymmetrical)