Revisión del plan de obras en ejecución

APICAL PERIODONTAL CYST)

• Most common cyst

• Both radicular & residual – 60.3% of odontogenic cysts

• Age – III, IV & V decades

• Rarely in I decade - though dentigerous cyst is common in children radicular cyst are not often assoc with deciduous teeth

PATHOGENESIS OF CYST FORMATION 1. Phase of initiation

2. Phase of cyst formation 3. Phase of expansion

CLINICAL FEATURES

• M > F

• 60% - maxilla – anteriors 40% mandible

• Presence of non-vital tooth

• Generally asymptomatic unless they are secondarily infected

• Discovered on routine radiographs

• Vary in size from 1/2 to 2 centimeters or more in diameter

• Maxilla – buccal / palatal mandible – labial/ buccal rarely lingual

• If infected - Accompanied by pain and the other signs and symptoms of inflammatory infectious processes – sinus formation

• Large sized cysts  intraoral or facial accidental secondary fractures of bone

RADIOLOGICAL FEATURES

• Peri- or para-apical, round or oval radiolucency of variable size

• Generally well delineated

• Most likely with a marked radiopaque rim

• Rarely resorption of the root of the affected tooth

• Similar periapical radiolucent appearance granulomas, neoplasms of various origin and some diseases of bone

FORMATION

anteriors 40% mandible

Generally asymptomatic unless they are

radiographs

Vary in size from 1/2 to 2 centimeters or more

buccal / palatal enlargement, / buccal rarely lingual Accompanied by pain and the other signs and symptoms of

inflammatory-sinus formation secondary fractures of bone

apical, round or oval radiolucency

Most likely with a marked radiopaque rim Rarely resorption of the root of the affected

radiolucent appearance - granulomas, neoplasms of various origin and

• Not to rely on the radiographic size of a periapical radiolucency to establish the diagnosis of either cyst or granuloma, unless the lesion is larger than 2 cm in

• 10% of periapical radiolucencies in endodontically treated teeth are cysts remaining either a residual granulomatous tissue, a collagenous scar as a consequence to the endodontic treatment

HISTOPATHOLOGY

• Lumen is filled with fluid and cellular debris.

• Lined by non keratinized

epithelium which may show hyperplasia ( cell layers) & spongiosis

• Discontinuous in areas

• Arcading pattern of proliferation with intense

• Rushton’s hyaline bodies

May be present within the lining / occasionally capsule

10% of cysts

0.1 mm

Linear/st/curved hairpin like calcified structures

Concentrically laminated

Brittle & fracture

Odontogenic origin

keratin - Ker sec enamel cuticle Takeda Wertheimer

Hematogenous origin

thrombi in venules of CT which were varicose & strangled by epi

Recent – secretory product of odontogenic epithelium

• Dystrophic calcification, cholesterol clefts surrounded by dense aggregates of foreign body multi nucleate giant cells

which eventually are extruded out)

• Haemorrhage and hemosiderin pigmentation may be seen – some capsules markedly vascular

Not to rely on the radiographic size of a periapical radiolucency to establish the diagnosis of either cyst or granuloma, unless the lesion is larger than 2 cm in diameter 10% of periapical radiolucencies in endodontically treated teeth are cysts - remaining either a residual granulomatous tissue, a collagenous scar as a consequence to the endodontic treatment

Lumen is filled with fluid and cellular debris.

keratinized stratified squamous epithelium which may show hyperplasia (1-50 cell layers) & spongiosis

Discontinuous in areas

Arcading pattern of proliferation with intense ammatory process – early stages With cyst enlargement - quiescent & fairly simple stratified squamous

The wall consists of dense fibrous connective tissue with a predominant chronic inflammatory infiltrate – many plasma cells ell bodies (collections of Igs), mast

Rushton’s hyaline bodies

May be present within the lining / capsule

/curved hairpin like calcified

Concentrically laminated

gin - ?? Some form of Ker sec enamel cuticle – Rushton, Takeda Wertheimer

origin – derived from thrombi in venules of CT which were

& strangled by epithelial cuffs secretory product of odontogenic

Dystrophic calcification, cholesterol clefts rounded by dense aggregates of foreign multi nucleate giant cells (mural nodules which eventually are extruded out)

Haemorrhage and hemosiderin pigmentation some capsules markedly

cysts & part of the lining

• Metaplastic changes – mucous cells & ciliated cells frequently found

• Islands of squamous epithelium developed from rests of Malassez in a periapical granuloma without cystic transformation - referred as "bay cyst“

FNAC

• Straw colored fluid

• Cholesterol crystals

• Protein levels- 5-11g/dl

• Smear -Inflammatory cells

• Arises as a consequence of an improper surgical elimination of a radicular cyst

• Identical clinical and histological characteristics to those of a radicular cyst

• Become less inflamed  cause removed

Cyst wall uninflammed collagenous fibrous tissue

Thin & regular epithelium lining – similar to DC / LPC

• Radiologically - radiolucency of variable size at the site of a previous tooth extraction

Paradental cyst / Inflammatory collateral cyst / inflammatory periodontal cyst

Mandibular infected buccal cyst / Juvenile Paradental cyst

60% of PD cysts 36% of PD cysts

Main (1970, 1985) & Craig (1976) Stoneman & Worth (1983)

Adults, III decade Young children8 & 9 yrs & 13 &19 yrs

III molars (vital teeth) I & II mandibular molars & premolars (vital teeth)

Partially erupted Partially / fully erupted

Lateral aspect (distal / distobuccal surface) of root Buccal surfaces of root – bifurcation inv

H/O pericoronitis H/O Pericoronitis

• Cyst continuous with pericoronal / PDD pocket

• Associated with buccal enamel spur projecting towards furcation

• Discovered accidentally

• Occasional swelling

• More severe clinical signs & symptoms – related to anatomical diff in mandible

• Swelling, pain, tenderness & suppuration

• Tooth tipped buccally

• Painful occlusion

• Facial swelling with pointing abscess

• Deep PD pockets continuous with cyst lumen

• Well demarcated distal / distobuccal RL super- imposed over roots

• Distal follicular space preserved

• Lamina dura intact / no widening of PDL space – apical region

• Well demarcated RL over buccal aspect of roots

• Buccal expansion with corticated outline /Loss of buccal cortex

• Tooth buccally tilted – roots close to lingual cortex

• Cyst – large – displace adjacent tooth crypt

• Furcation inv – loss of inter-radicular bone

• Lamina dura intact / no widening of PDL space

© BRIHASPATHI ACADEMY ׀ SUBSCRIBER’S COPY ׀ NOT FOR SALE PATHOGENESIS

• Origin – REE / rests of M / non-odontogenic epi (sinus / crevicular epithelium)

• REE

Extended portion of REE over enamel spur

Unilateral expansion of dental follicle sec to inflammatory destruction of PDL &

bone

Rests of Malassez

Inflammatory origin- pericoronitis  stimulated rests of M

Demonstrated continuity b/w cyst epithelium

& REE / Pericoronal / PDD pocket

PDC – dilated follicle lined by hyperplastic REE – ‘eruption pocket cysts’ / ‘inflammatory pocket cysts’

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