Cysts in and around the Jaws PDF

Pathogenesis of a cyst is mainly divided into three stages: COMMON FEATURES OF JAW CYST (1) Cyst Initiation,...

Pathogenesis of a cyst is mainly divided into three stages: COMMON FEATURES OF JAW CYST (1) Cyst Initiation, enlarge slowly, mechanism: 1) hydrostatic pressure. (2) Cyst Formation, poor lymphatic drainage, semipermeable wall and lining, intermittent osmotic pressure higher than the capillary blood (3) Cyst enlargement or expansion pressure, 5 years for a cyst in the mandible to enlarge to a few Theories of Cyst Enlargement/Expansion centimetres diameter in an adult, faster in children. Mural Growth & Peripheral Cell Division 2) Growth of the wall (keratocysts) epithelial lining has a high mitotic rate, lumen is filled with Hydrostatic Enlargement keratin exerts little osmotic pressure. budding and insinuating finger-like processes or developing Bone Resorbing Factor outpouchings that extend into adjacent bone. resorb the cortex and push the inferior dental canal out of the way. 3) Growth pattern and effects on adjacent structures Cysts grow like a balloon, forming a hollow sphere by resorbing medullary bone 4) Expansion resorb the cortex and push the inferior dental canal out of the way Classification Cysts of the jaws With epithelial lining: Odontogenic Cysts: 90% odontogenic epithelium under the Cysts are pathological fluid-filled Non-Odontogenic Cysts: microscope that shows basal cells cavities lined by epithelium. 10% resembling ameloblasts Inflammatory: Developmental: most common cause of chronic Radicular (70%) Incisive canal cyst Rushton bodies (hyaline bodies), ▪ Dentigerous (15%) swellings of the jaws. enamel matrix-like secretory Apical (75%) ▪ Eruption Gingival cyst of infants Nasolabial cyst cyst comprises a wall of fibrous Lateral (5%) product. Gingival cyst of adults Sublingual dermoid cyst tissue and a central lumen, or Residual (20%) ▪ Keratocyst (5%) space, lined by epithelium Thyroglossal duct cyst ▪ Paradental (3%) Lateral Periodontal ▪ Glandular Odontogenic Branchial cyst Calcifying Od. Cyst Foregut cysts Orthokeratinized Od. cyst Cysts are divided into: odontogenic cysts, Without epithelial lining (pseudocyst) : nonodontogenic cysts, Cysts of the soft tissue & neck cysts. Solitary (simple; traumatic,) Bone Cyst Pseudocysts without epithelial lining , Aneurysmal Bone Cyst Cysts in and around the jaws Stafne’s idiopathic Bone cavity Oral Pathology 3rd lecture Dr. Hasnaa’ Makkawi Dr. Omar Imran chapter 10 / cawson’s Treatments Radiography Enucleation and primary closure is the usual Residual radicular cyst method of treatment and is usually entirely rounded, effective radiolucent Marsupialisation, or decompression, was a largely sharply defined outline. outmoded treatment but has regained popularity for very large odontogenic keratocysts. A condensed radiopaque corticated periphery Curettage is the scraping of the bony cavity after is present only if growth is slow and is usually enucleation or piecemeal removal of a lesion more prominent in longstanding cysts. large carious cavity Infected cysts, treated first by antibiotics and drainage Adjacent teeth may be tilted or displaced. Soft tissue cysts, excised (removed by cutting around them) with a small margin of normal tissue, Clinical presentation: ODONTOGENIC CYSTS Histologic features RADICULAR CYST or periapical cysts most common chronic swellings arcading epithelium, irregular, inflammatory in type variable thickness, hyperplastic defined by its location at the apex numerous neutrophils emigrating non-vital tooth into the lumen more common in males Maxilla 3x mandible Mucous metaplasia slowly progressive painless swelling Hyaline or Rushton bodies. rounded Hard-------eggshell-------- soft fluctuant swelling, bluish in Often treated by enuculation expand buccally first, except in the lower molar region where the lingual cortex is closer and thinner. Symptomless and tooth vitality is not affected by cysts unless infected. Pathology and histology A bluish color is characteristic of cysts that have expanded beyond the cortex inflammation prolifration Radiological features epithelial rests Fluid sharply defined evenly radiolucent lesions with a smooth rounded outline. Granuloma of Malassez cavity accumulation thin cortical or sclerotic layer around any cyst that grows slowly enough Induce Cysts may be unilocular (one cavity) or multilocular (many cavities) scalloped outline, and septa. Fluid content: Most cyst fluids are watery and opalescent viscid and yellowish, thick white paste (keratocyte) shimmer with cholesterol crystal pus (infected cysts) radiographically Odontogenic keratocyst histology The odontogenic keratocyst is a developmental odontogenic cyst with a Central type tendency to recur, characterised by a histological appearance of biopsy is the definitive diagnostic investigation parakeratinised lining epithelium with palisaded ameloblast-like basal cells Lateral type Thin fibrous wall (tensile & rupture -----recurrence) Dental lamina (rests of Serres) Circumferential type 6-10 layers of ssq Clinically: Flat junction Wide age range, 2nd-3rd decade epith. Parakeratinized Mandible, 3rd molar & ramus area Palisaded basal cell layer (resemble pre- Ant-Post direction ameloblasts) Symptomless until well advanced mitotic activity of basal & parabasal layers recur after treatment, syndromic presentation.(mutation in the PATCH gene) DENTIGEROUS CYSTS Eruption cyst Rx Well defined radiolucency with a scalloped margin common cyst surrounds the crown Variant of DC Unilocular or Multilocular/polycystic radiolucency Attached to CEJ & covers part or all of the crown Tooth’s crown within soft tissue Unerupted tooth Missing tooth, jaw expansion, , pain Soft, fluctuant mass on alveolar ridge Displace roots, ↓root resorption vs. radicular cyst or dentigerous cyst L8>U3>U8>L5 Primary & permanent growth pattern is almost diagnostic. Treatment enucleation with removal of the unerupted tooth. Inflammation forward and backward along the medullary cavity minimal expansion The lack of expansion ----large at time of discovery. syndromic presentation.(mutation in the PTCH gene tumour suppressor gene) Lateral radicular cyst histology Mutation results in a relatively high proliferative activity in the cyst lining epithelium. forms at the side of a non-vital tooth root at the opening of a lateral uninflamed fibrous wall lined by This has consequences. branch of the root canal a thin, bilaminar, epithelium that resembles reduced enamel 1) growth of the wall rather than internal pressure. need to be distinguished from lateral periodontal cysts epithelium 2) recurrence mucous cells or focal 3) The lining becomes folded(septum) kératinisation 4) Extensions of the lining (daughter cysts) multilocular lesion. If inflammé resmble radicular cyst.  Basal cell naevus syndrome (Gorlin’s or Differential diagnosis Histologically Gorlin-Goltz syndrome) Rx Characterized by triade: Biopsy multiple basal cell carcinomas (naevoids), May resemble: odontogenic keratocysts multilocular kc--- ameloblastoma various skeletal anomalies Teeth included kc---- dentigerous cyst Caused by autosomal dominant mutation of the PTCH gene Diagnosis with biopsy Content: clear fluid or thick gray/white cheesy, Keratin filling the cyst lumen Treatment: (diagnostic tool) Enucleation with curettage for small multilocular or unilocular cysts. ORTHOKERATINISED ODONTOGENIC CYST If infected or inflamed: treatment of the cavity wall with a fixative (Carnoy’s solution) as it: epithelial lining undergoes hyperplasia 3.3% -12.2% of KCs toughen the lining for removal Cyst inflammatory cell infiltrates Solitary, not associated with NBCCS. Kill and denatures 1-2mm depth Resemble radicular cyst. Unilocular Marsupialization followed by enucleation for large cysts ( very long 20 month disadv.) Associated with impacted teeth Very complex and extensive cysts ( resection and reconstruction. Not aggressive cysts; low proliferative activity. Follow up Rx. Very low recurrence rate Treatment: enucleation Might be similar to DC. Epith weak attachment to wall-----scattered islands of odontogenic epithelium. -----satellite’ Treatment and recurrence Clinical features or ‘daughter’ cysts-----mulktilocular Occasionally (7% to 30%): Satellite (daughter) recurrence rates of more than cysts 50% if only enucleation removal Larger cysts have a higher risk of recurrence Multi-rooted tooth involved within the cyst should be sacrifices recurrence is often within the first 5 years after treatment  Botryoid odontogenic cysts CALCIFYING ODONTOGENIC CYST GINGIVAL CYST rare variant of the lateral periodontal cyst that is multilocular Clinically: Rests of Serres rare Clinically: Differential diagnosis with keratocyst Firm compressible, Usually < 40 Lobular Anterior to 6 fluid-filled swelling Max or Mand buccal gingiva plaque Slowly enlarging painless swelling Premolar; canine; incisor region 25% extraosseous Age 40 y Rx: Rx: saucerization uni/multilocular radiolucency containing radiopaque flecks In newborn gingival cysts (Bohn’s Nodules): Unerupted tooth Keratin content (white color) Resorption of adjacent roots Resolve spontaneously by 3 months of age as a result of rupture of these cysts histology histological treatment diagnostic Diagnostic enucleation is usually effective 1-3 layers of non-keratinized small glands that are lined by stratified squamous eipth with Differential diagnosis: glycogen-rich clear Cytoplasm mucous cells and secrete mucin and lie in thickenings of the epithelial solid odontogenic tumour Focal epithelial thickenings lining (Plaques) treatment: enucleation with Differential diagnosis : retaining of the residual teeth. similar to the clinical and Rx Differential diagnosis : appearance of OKC. radicular cyst (nonvital) histology LATERAL PERIODONTAL CYSTS GLANDULAR ODONTOGENIC CYST lining of the cyst looks like ameloblastoma ameloblast-like basal cells uncommon epithelium with cuboidal or ameloblast- like basal cells Rests of Malasseze rare odontogenic cyst (sialo-odontogenic cyst) Ghost thick layer of stellate reticulum approximately 50 y middle-aged The diagnostic feature is ghost cells Mand premolar/canine; Max between 2 & 3 unilocular or multilocular may calcify in a patchy fashion, giving the cyst its name and producing the spotty Ghost Rx: small (1cm), w-d, unilocular expand the jaw radiopacities that give a clue to the radiolucency between roots displace and resorb teeth diagnosis. mid portion of the root Vital teeth Where this keratin like material comes into Recur after enucleation ( additional curettage and sacrificing of the contact with connective tissue, it induces a Teardrop shaped teeth) dentine-like matrix or mineralized tissue expand the jaw called dentinoid. displace teeth. 10% of calcifying odontogenic cysts are dentinoid associated with odontomes or other odontogenic tumour NASOPALATINE DUCT OR INCISIVE CANAL CYST SUBLINGUAL DERMOID CYST above the hyoid and mylohyoid, Remnants of the vestigial duct immediately beneath the tongue around 5% of jaw cysts and making this the commonest usually in the midline, occasionally to one side non-odontogenic cyst of the jaws A sublingual dermoid is more deeply placed Clinical features: asymptomatic when small, incisive canal large ----to interfere with speech or eating and can presentation depends on where in the canal they form: attain a large size over many year. Histology: superficial ----soft tissue cyst in the incisive papilla They are lined by a keratinizing stratified squamous oral end--grow primarily into the nose epithelium like skin, associated sebaceous glands, superior end--grow slowly in the bone of the anterior palate if they arise sweat glands in the middle hair follicles Burst Differential diagnosis: Cysts from the middle --expand palate downward and upward, while epidermoid cysts.( more superficial and lack skin they grow forward, over or between the central incisor apices to expand adnexa) the anterior alveolus in the midline. BRANCHIAL CYST NASOLABIAL CYST Failure of fusion of the five arches can leave embryological remnants in the neck that can give rise very uncommon cyst forms outside the to branchial cysts bone in the soft tissues anterior border of sternomastoid muscle below the nasolacrimal duct angle of the mandible. Female more than male Deep between the carotid and the pharynx Non odontogenic cysts Uni/bilateral cyst Differential diagnosis: Clinically: lymphoepithelial cysts arising in lymph nodes at a soft tissue swellings in the upper lip, distort the nostril similar site (superficial) Histology: Histology: The lining is pseudostratified columnar respiratory lined by non-keratinising squamous epithelium and epithelium often have lymphoid tissue in their wall. Treatment: excision THYROGLOSSAL DUCT CYST histology Rx Embryological epithelial remnants of the thyroglossal duct. rounded radiolucent area with a corticated Similar to lateral periodontal cyst outline at the site of the incisive canal dorsum of tongue to the site of the thyroid gland Thin layer of ssq epithelium heart-shaped Thyroglossal cysts are the commonest neck cyst Displaced roots l present in the area of the body of the hyoid bone May contain fluid or keratin Histology: Classically the cyst rises on swallowing while the Some times plaque similar to LPC. tongue moves upward. stratified squamous epithelium or ciliated columnar (respiratory) epithelium with mucous Histology: glands. e lined by stratified squamous epithelium or Treatment: respiratory epithelium, and there are often clusters of ectopic thyroid tissue in the wall enucleated without recurrence. Treatment: removed surgically with the body of the hyoid bone and tissue along the line of the tract down to the gland,