6 - Pathology Flashcards

Question

Cementoblastoma

Answer 1

* Epidemiology * \< 20 yrs of age * M \> F * 80% Mandible * 50% involve the first lower molar * Pathophysiology * Cementoblasts slowly lays down cementum and obliterates the surrounding periodontal ligament space and bone * Presentation / Progression * Pain on palpation or biting * Vital tooth * Slow growing * Expansile lesion * Imaging * Calcified opacity * Mass blends with root of tooth * cf Condensing Osteitis - Sclerosis of bone does not resorb and obscure root outline * Peripheral radiolucent zone * Histology * Very similar in appearance to Osteoblastoma Cementoblastoma is intimate contact with root * Dentine like material * Irregularly placed lacunae and prominent reversal lines * Mineralised material rimmed by cementoblasts * Multinucleate giant cells often present * Treatment * Extraction + excision of lesion * RCT + Root amputation * Recurrence rate 12% - Chrcanovic

Answer 2

* Epidemiology * 20 - 50 yrs of age * M\>F * Mand \> Max * Associated with Gardner's Syndrome * Pathophysiology * Unknown cause * ?Trauma * Presentation * Painless * Asymptomatic * Firm lump of bone * Jaw osteomas typically affects * mandibular body and condyle * Slow growing * Displacement of teeth * Histology * Compact osteoma - Normal appearing dense bone with minimal marrow * Cancellous osteoma - Bony trabeculae and fibrofatty tissue * Treatment * Surgical excision often done for diagnosis * Asymptomatic cases can be monitored * Recurrence is rare * Malignant transformation * No malignant transformation **Gardner's Syndrome** * Epidemiology * 1: 10 000 * APC gene - Autosomal dominant Adenomatous polyposis coli gene * Pathophysiology * Form of Familial adenomatous polyposis * Characterizd by multiple colorectal polyps and other benign and malignant lesions * Mutation on the APC gene - Tumor suppressor gene * Monitors cell growth and division * Presentation * GI * Intestinal polyps * 50% will have colon cancer by age 30 * PR bleeding, Anaemia * Osteomas * 90% will have multiple osteomas * Most commonly skull, paranasal sinuses and mandible * Dental * Odontomas * Supernumerary teeth * Impacted teeth * Skin * Epidermoid cysts * Lipomas * Neurofibromas * Desmoid tumors * Differentials for Intestinal Polyps * Turcot syndrome * Cowden syndrome * Peutz Jegher syndrome

Answer 3

Bony counterpart to Desmoid Tumours * Epidemiology * \<20 yrs of age * Mand \> Max * Pathophysiology * Unknown etiology * Presentation / Progression * Painless swelling * Can cause dental displacement and root resorption * 1/4 unilocular, 3/4 multilocular * Expansile with cortical thinning * Histology * Identical to soft tissue Desmoid tumour * Small elongated fibroblasts * Abundant collagen in dense interlacing bundles * No bone formation * Treatment * Currettage - 30% Recurrence * Resection - 5% Recurrence

Answer 4

* Ghost Cells * Pale eosinophillic epithelial cells which have lost their nucleus but retain the cell outline * Eosin refers to staining of the cell not Eosinophil * Stains (Pink) * Associated Pathology * Calcifying odontogenic cyst / Gorlin's cyst / Calcifying cystic odontogenic tumor * Dentinogenic ghost cell tumour * Ghost cell odontogenic carcinoma * Ameloblastic spectrum with ghost cells - Less ghost cells than DGCT

Answer 5

* Clear cells * Some secretory cells in the epithelium appear as clear cells and are one of the components of eccrine sweat glands * The cytoplasm contains large amounts of glycogen and mitchondria * Melanocytes appear as clear cells when in the stratum basale * Langerhans cells appear as clear cells in the stratum spinosum * Associated Pathology * Calcifying odontogenic epithelial tumor / Pindborg tumor * Mucoepidermoid carcinoma - 10% of tumor population * Clear cell odontogenic carcinoma

Answer 6

Spectrum of lesions involving odontogenic epithelium containing ghost cells Lesions may subsequently calcify * Classification * 95% Cystic - Calcifying odontogenic cyst / Calcifying cystic odontogenic tumor * Intraosseous 75% * Extraosseous 25% * 5% Tumor - Dentinogenic ghost cell tumor * Malignant - Ghost cell odontogenic carcinoma * **Calcifying odontogenic cyst - Gorlin's cyst** * Epidemiology * Most common in 30 yrs of age Younger if associated with unerupted teeth and odontomes 20% associated with odontomes * Posterior mandible most common site * Pathophysiology * Unknown cause * Presentation / Progression * Associated with unerupted teeth * Associated with root resorption * Most common in incisor and canine region with unerupted teeth * Imaging * Unilocular, well defined * Radio-opaque flecks * Histology * 4-10 cell thick odontogenic epithelium * Resemble ameloblastoma * Basal pallisading columnar cells with reverse polarity * Stellate reticulum like epithelium * Ghost cells within epithelium * Eosinophilic * Large and pale * Can coalesce and become calcified * Management * Slow growing * Recurrence is rare * Enucleate * Malignant Transformation * Rarely carcinoma arise in Calcifying odontogenic cyst * **Dentinogenic Ghost Cell Tumor** * Solid variant of COC * More often Extraosseous than Intraosseous * Difficult to distinguish from COC radiographically * Histology * Ameloblastomatous islands of epihelium in mature stroma * Have nests of ghost cells preent within epithelium - differentiates it from a peripheral ameloblastoma * Aberrant keratinisation may be found in the form of ghost cells with dysplastic dentine * Treatment * Can be aggressive - therefore wide local excision * **Ghost cell odontogenic carcinoma** * Dentinogenic ghost cell tumor that undergoes malignant transformation * Histology * Both epithelial and ectomesenchyme components are present but only epithelial component is malignant * Cellular pleomorphism * Increased mitotic activity * Invasion of surrounding tissues * Diagnosis based on identifying benign features of COC or DGCT with malignant features * Treatment * Wide local excision * Recurrence common * 75% survival at 5 years

Answer 7

* Ectodermal origin * Ameloblastoma * Coventional * 6 Histological variants * Unicystic * Ackerman classification * Peripheral * Squmous odontogenic tumor * Calcifying epithelial odontogenic tumor * Adenomatoid odontogenic tumor * Ectomesenchyme origin * Ameloblastic fibroma * Dentinogenic ghost cell tumor * Odontoma * Complex / Compound * Primodial odontogenic tumor * Mesenchye origin * Odontogenic fibroma * Odontogenic myxoma * Cemento-ossifying fibroma * Juvenile ossifying fibroma * Cementoblastoma

Answer 8

* Odontogenic carcinomas * Ameloblastic carcinoma * Ghost cell odontogenic carcinoma * Clear cell odontogenic carcinoma * Primary osseous carcinoma * Sclerosing odontogenic carcinoma * Odontogenic carcinosarcoma * Odontogenic sarcoma

Answer 9

* Pre-malignant conditions * Discoid lupus erythematosis * Spectrum condition of Lupus erythematosus * Autoimmune mediated * Pathophysiology * Autoimmune condition to unknown antigen * Sun exposure can trigger these lesions * Presentation / Prognosis * Purplish red flat or raised patches * Increasing amounts of white scale * Darker skinned patients often have severe scarring * Fanconi anaemia * Rare genetic disease of FA genes resulting in impaired response to DNA damage * Pathophysiology * Autosomal recessive * FA genes - Responsible for DNA repair * Presentation / Progression * Bone marrow failure - Variable anaemia * AML * Short stature * Endocrinopathies * Cafe au lait spots * Dyskeratosis congentia * Congenital disorder of variable phenotype * Shot telomeres - manifests as premature ageing with bone marrow failure * X-Linked recessive * Pathophysiology * Mutation DKC gene on the X chromosome * Short telomeres * Presentation / Progression * Variable phenotype but typically * Nail dystrophy * Leukoplakia * Abnormal pigmentation * Myelodysplastic syndrome is associated with this condition * Xeroderma pigmentosum * Autosomal recessive * Genetic disorder where there is a decreased ability to repair DNA caused by UV light * Pathophysiology * Autosomal recessive mutation on NER (Nucleotide excision repair) enzyme * Presentation / Progression * Corneal ulcerations * Xeroderma (Dry skin) * Hyperpigmentation * Blistering and freckling on minimum sun exposure * Plummer Vinson syndrome * Rare disease characterized suspected to be due to nutritional deficiencies * Pathophysiology * Possible nutritional deficiency * Treated with Iron supplementation * Possible genetic factors * Presentation / Progression * Occurs in peri-menopausal women * Characterized by: * Difficulty swallowing * Angular cheilitis * Oesophageal webs * Iron deficiency anaemia * Glossitis * Epidermolysis bullosa * Rare group of medical conditions that results in easy blistering of skin and mucous membranes * Pathophysiology * Mutation can be due to 16 different genes * Lack of protein anchors that hold the skin together Leads to shearing of skin * Chronic skin damage leads to increased risk of malignancies * Presentation / Progression * Classified into four types * Epidermolysis bullosa simplex * Junctional Epidermolysis bullosa * Dystrophic Epidermolysis bullosa * Kindler syndrome * Blistering of skin and mucous membranes * Graft vs Host disease * Immune reaction from donor's tissue towards the host * The opposite of Transplant rejection * Typically associated wtih bone marrow and stem cell transplants * In the oral cavity, chronic graft vs host disease manifests as Lichen reaction with a higher risk of malignant transformation

Answer 10

* See attached image * Odontogenic vs Non-odontogenic * Developmental vs Acquired

Answer 11

* **Developmental** * Dentigerous Cyst * Classification * Central - Cyst surrounds crown * Lateral - Grows on one side (Mesioangular lower 8) * Circumferential - Encloses whole tooth * Presentation / Progression * Encloses crown and attaches to CEJ * Asymptomatic * Can resorb adjacent roots * Pathophysiology * Alteration of reduced enamel epithelium (after tooth development) leads to cystic formation. Due to fluid between REE and Tooth * Histology * Non keratinised stratified squamous epithelium * 4-6 cells thick * Loosely arranged fibrous connective tissue wall * Treatment * Enucleation * OKC - Parakeratinised * OKC - Orthokeratinised * Lateral periodontal cyst / Botryoid Cyst * Botryoid cyst is considered the multicystic variant of LPC * Presentation / Progression * M:F - 2:1 * 50 - 70 yr olds * Occurs in the PDL space * Asymptomatic * Vital Teeth * Displaced teeth * Can resorb roots * Pathophysiology * Unclear etiology * May arise from Rests of Serres (Dental lamina remnants) * Histology * Thin walled - 1 to 2 cells thick * Non keratinised SSE * Glycogen rich clear cells may be interspersed in the lining or seen within fibrous connective tissue * Localised areas of thickening along epithelium * Treatment * Enucleation (Chrcanovic - 2019) * Lateral periodontal - 2.5% * Botryoid - 22% * Consider adjuncts with enucleation * Gingival cyst * Soft tissue counterpart to Lateral periodontal cyst * Presentation / Progression * 50 - 60 yr olds * Blue grey lesion * Less than 5mm * May cause cupping of the alveolar bone underneath * Pathophysiology * Derived from Rests of Serres (Dental Lamina) * Histology * Similar to Lateral periodontal cyst * Thin cyst - 1 to 3 cells * Small nests of glycogen rich clear cells in surrounding connective tissue * Can contain plaque like thickening along cavity wall * Treatment * Simple excision * Calcifying odontogenic cyst * Part of the spectrum along with Dentinogenic ghost cell tumor and Ghost cell odontogenic carcinoma * Presentation / Progression * 30 yr olds * Presents younger if associated with teeth / odontomes * Rarely undergoes malignant transformation * 75% Intraosseous, 25% Extraosseous * Can have radio-opaque flecks * Associated with underupted teeth and resorption * 20% associated with odontomes * Pathophysiology * Unknown cause * Histology * Ameloblast cells form cyst lining - Can look like ameloblastoma * Ghost cells present within epithelium * Eosinophillic epithelial cells which have lost their nucleus * Large and pink * Can coalesce and become calcified * Treatment * Enucleate * Glandular odontogenic cyst * Classified as odontogenic origin. Can show salivary features Likely indicates pluripotent nature of odontogenic behaviour * Presentation / Progression * 50 yr old * Mand \> Max * 80% anterior mandible * Behaves like ameloblastoma - aggressive behaviour with recurrence * Imaging * Uni or multilocular * Well defined cortical rim * Pathophysiology * Mutated cell from epithelial origin - undergoes maturation to a glandular differentiation * Histology * Squamous cuboidal cells * Intra-epithelial microcysts filled with mucin * May contain ciliated and goblet cells * Treatment * Enucleation - 22% * Adjuncts recommended with enucleation * Recurrence up to 8 yrs * Eruption cyst * Presentation / Progression * Bluish swelling that occurs over soft tissue of an eruptin tooth * Considered superficial dentigerous cyst * Histology * Non keratinised squamous epithelium * Treatment * Marsupialization and decompression of cyst * Monitor - can burst spontaneously * **Acquired** * Radicular cyst * Presentation / Progression * Most common cyst * M \> F * Associated with the apex of Non-vital teeth * Pathophysiology * Develops from from pre-existing Apical granuloma * Histology * Focus of chronically inflammed tissue at the apex of non-vital teeth * Central necrosis * May be cholesterol clefts or giant cells in wall due to RBC breakdown * Inflammatory infiltrate * Non keratinised SSE * 10% Contain Rushton bodies - Proteinaceous material (Hyaline bodies) * Treatment * Enucleate + Treat non vital dentition * Paradental cyst * Inflammed Lateral Dentigerous cyst * Presentation / Progression * Pain and tendernes with infective hx * Pathphysiology * Aleration of Reduced enamel epithelium leading to cystic formation. Infection of cyst * Can also originate from proliferation of Rests of Malassez from PDL * Histology * Non keratinised SSE * Variable thickness * Fibrous wall * Inflammatory cells * Treatment * Enucleation * Buccal bifurcation cyst * Presentation / Progression * Occurs in children * Associated with lower 6s * 1/3 are bilateral * Imaging * Well circumscribed radiolucency * Distinct U shaped lesion * Pathophysiology * Triggered by infection or food debri impaction * Histology * Identical to Radicular cyst on histology * Non keratinised SSE * May be cholesterol clefts or giant cells in wall due to RBC breakdown * Inflammatory infiltrate * Non keratinised SSE * 10% Contain Rushton bodies - Proteinaceous material (Hyaline bodies) * Treatment * Enucleate leaving the tooth

Answer 12

Non-Odontogenic Cysts * **Developmental** * Lymphoepithelial cyst * Presentation / Progression * OKC with lymphoid tissue in wall * Occurs at the sites of lymphoid tissue * Commonly FOM, lateral & posterior tongue and tonsil pillars * Pathophysiology * Arises from entrapment of epithelium within lymph nodes or lymphoid tissue during development * Blind ended epithelial invagination into lymphoid tissue that may lead to a tract that become filled with keratin * Histology * Lined by parakeratinised stratified squamous epithelium (Similar to OKC) * Epithelial lining surrounded by discrete lymphoid component * Cyst wall contains variable proportions of lymphocytes, macrophages and plasma cells * Cyst lining may be continuous with surface epithelium * Treatment * Thyroglossal duct cyst * Presentation / Progression * Most common developmental cyst of the neck * 7% of the population * Any age * Midline lesion but 20% para-median * Moves with tongue on protrusion * Imaging * Thyroid scan - Iodine 131 * Determines presence of thyroid tissue in neck or lingual thyroid * US - can show tract and lesion * Pathophysiology * Remnant of epithelial cells from the descent of thyroid gland * Thyroid develops around Foramen cecum - 3 to 4 weeks * Descends - 4 to 8 weeks * Involution of duct - 8 to 10 weeks * Distal portion may persist at the pyramidal lobe in up to 50% of the population * Histology * Lining of psudostratified columnar epithelium * Frequently contain thyroid follicles and thyroid colloid * Treatment * Sistrunk procedure * Excison of cyst and entire tract all the way up to tongue * Centre of hyoid bone usually invovled in excision Can excise lesion from periosteum as an alternative * Ligation of duct as far proximal as possible * Recurrence is rare * Branchial cleft cyst * Presentation / Progression * Also known as cervical lymphoepithelial cyst Contains epithelial cells and lymphoid tissue/germinal centres * 20 - 30 yr old * II branchial arch - 95% * Bailey Classification for II arch cysts * Based on depth * I - Deep to platysma * II - Superficial to Carotidy body * III - Passing between Carotid arteries * IV - On pharyngeal wall * I - 5% * Incidental finding or activation of activation of lymphoid tissue during infection * Branchial arches cleft cyst locations: * I - Near angle of mandible. Can extend to auricle * II - Located anterior to SCM (Inf and mid third) * III - Extend from SCM (Inf and mid third) to piriform fossa * IV - Parallels the course fo the recurrent laryngeal nerve. Begins at the piriform fossa and extend to the thyroid * Pathophysiology * Two theories * Cleft between branchial arches fails to completely involute * Cystic transformation of cervical lymph nodes * Histology * Lined by SSE * Lymphocytes and germinal centres * Same as lymphoepithelial cyst - cystic degeneration of lymph node * Treatment * Sclerotherapy with Picibanil * Surgery * Excision and ligation of residual tract * Dermoid cyst * Presentation / Progression * Dermoid cyst contains adnexal structures cf Epidermoid cyst (Sebaceous cyst) - Epithelial cells * Most common site is the lateral brow * Asymptomatic swelling * Pathophysiology * Improper fusion of skin layers * Histology * Line by SSE * Fibrous connective tissue wall * Contain adnexal structures * Hair follicles * Sebaceous glands * Sweat glands * Teratoid variety includes elements of all germ cell layers * Teeth * Bone * Muscle * Treatment * Surgical excision * Recurrence is rare * **Acquired** * Simple bone cyst / Solitary bone cyst * Presentation / Progression * Not a true cyst - Lacks epithelial lining * Occurs in younger patients * Asymptomatic * No bony expansion * Vital dentition * Radiolucent lesion with sclerotic bone that scallops around the teeth * Pathophysiology * FITH * Fibro-osseous lesion resolving * Ischaemia - Necrosis leading to interruption of venous drainage leading to increased intramedullary pressure which triggers osteoclastic bone resorption * Trauma - Intramedullary hemarrhage which resolves but is not replaced with bone * Hormones - changes during teenage years cause disturbances in remodelling of trabecular bone * Histology * Bone cavity with no epithelial lining * Serosanguinous material in the lumen * Treatment * Exploration and currettage the bone wall to stimulate bleeding and bone infill * Nasopalatine duct cyst * Presentation / Progression * Most common non-odontogenic cyst 1% of population * M\>F * 30 - 50 yrs of age * Asymptomatic soft swelling of the anterior hard palate * Vital teeth * Root resorption is rare * Fluctuating painful swelling can occur due to secondary infection * Imaging * Heart shaped appearance * Occurs between the central incisors * 7mm cut-off (Roper-Hall 1938) * Pathophysiology * Nasopalatine ducts runs either side of the nasal septum and exite at the incisive canal * Epithelial remnants of nasopalatine duct that have failed to degenerate can form cysts * Infection or trauma can stimulate cyst formation * Histology * Epithelial lined cyst * Stratified squamous or Cuboidal or Columnar * Pseudostratified columnar * Higher up in canal - More features of respiratory epithelium * Can have nerves, arteries, veins and minor salivary gland * Treatment * Enucleate * Recurrence is very low * Median palatal fissure cyst * Presentation / Progression * Fissural cyst due to the entrapment of epithelium along fusion line of lateral palatal shelves * Firm fluctuant swelling in midline of hard palate and posterior incisive canal * Can be difficult to distinguish from a posteriorly located Nasopalatine duct cyst * Pathophysiology * Due to the entrapment of epithelium along fusion of the lateral palatal shelves * Histology * Stratified squamous epithelium * No nerves, arteries or veins * Treatment * Excision * Recurrence low * Nasolabial cyst * Presentation / Progression * 30 - 40 yr olds * 10% bilateral * M \< F - 1:4 * Nasolabial swelling * Anywhere from alar crease to labial vestibule * Asymptomatic * Fluctuant * Pathophysiology * Two theories * Entrapped epithelial remnants at the junction of maxillary medial and lateral nasal processes * Ectopic epithelium of the Nasolacrimal duct * Deep to muscles of facial expression * May have respiratory epithelium * Histology * Line by pseudostratified columnar epithelium +/- goblet cells * Fibrous connective tissue wall * Treatment * Extracapsular excision * Can be performed trans-cutaneously or trans-orally if close to nasal floor * Part of the nasal mucosa may require excision * Mucous retention cyst * Presentation / Progression * True cyst - cf Mucous extravasation cyst * Asymptomatic swelling * Painful if infected * Pathophysiology * Obstruction of salivary duct that causes pooling of saliva and distension of the duct and or gland * True cyst - lined by epithelium * Histology * Lined by cuboidal, columnar, squamous cells * Mucoid secretions * Dilated ducts * Treatment * Excise if isolated * If within major gland - may require gland removal * Surgical ciliated cyst * Presentation / Progression * 30 - 40 yr olds * Occurs post trauma or surgery * Asymptomatic swelling * Pathophysiology * Occurs post trauma or surgery * Respiratory epithelium is trapped in foreign tissue in surgical site * Histology * Lined by respiratory epithelium * Pseudostratified columnar epithelium * Treatment * Excision of cyst

Answer 13

Benign Odontogenic Tumours - Epithelial * Ameloblastoma * Classification * Cystic - Ackermann Classification * Luminal - 10% * Intraluminal - 40% * Intramural - 50% * Conventional - Histological Classification * Follicular * Plexiform * Desmoplastic - can appear radio-opaque (Typically ant mand) * Granular * Acanthomatous * Basal cell * Peripheral * Metastasising * Presentation * 37% of all odontogenic tumors * 1 in 1 million per year * 80% mandible * 30 - 40 yr olds * Asymptomatic * Bony expansion * Resorbs teeth and leads to mobility * Pathophysiology * Arises from Rest of Serres (Dental lamina) * BRAF mutation in 80% * Over expression in BCL2 and RAS - excess signalling in MAPK pathway * Maxillary ameloblastoma can have mutations in SHH pathway * Histology * Islands of epithelium in FCT stroma * Ameloblast like cells with reverse polarity (towards centre of island) * Centre stellate reticulum with cystic degeneration * Histological subtypes * Follicular - Cysts * Plexiform - Follicular with no cysts * Acanthomatous - Forming keratin * Granular cell - Granular cells instead of stellate reticulum * Basal cell - Basal cell instead of stellate reticulum * Desmoplastic - Stands compressed by dense FCT * Treatment * High rate of recurrence up to 80% * Unicystic - Treat as cyst except for intramural * Conventional - Treat as tumor * Marx - up to 8mm from radiographic margin - Average 4.5mm Therefore 1.5cm margin * Engelbrecht - Perineural invasion * Recurrence - 50% in first 5 yrs - Can be up to 30 years * Adenomatoid odontogenic tumor * Classification * Follicular - 75% - Intraosseous lucency associated with the crown of unerupted tooth * Extra-follicular - 20% - Intraosseous lucency between roots of teeth * Peripheral 2% - Extraosseous * Presentation / Progression * 20 - 30 yr olds * M:F - 1:3 (2/3rd female) * 2/3 in maxilla * 2/3 associated with impacted canine * 2/3 radiolucent * Asymptomatic * Pathophysiology * Thought to arises from HERS / Rests of Malassez * Arises mid root level and encloses crown cf. Dentigerous cyst - arises from CEJ * Histology * Well encapsulated, thick capsule * Odontogenic epithelium in whorls, islands, rosettes Made from columnar ameloblast like ells not truly glandular * Central space can have stellate reticulum like material * Treatment * Enucleations * Recurrence very rare * Squamous odontogenic tumor * Presentation / Progression * Wide age range - Mean 30 yr olds * M:F - 2:1 * Benign tumor showing terminal squamous differentiation * Asymptomatic * Gingival swelling * Associated with mobility of teeth * Imaging * Triangular defect between roots * Vertical periodontal bone loss * Poorly defined margin * Uni or multilocular * Pathophysiology * Originates within the PDL associated with the lateral root surface * Arises from Rests of Seres (Dental Lamina) or Rests of Malassez (HERS) * Histology * Squamous islands in a dense fibrous connective tissue stroma * Can look like well differentiated SCC * Peripheral cells do not show reverse polarity seen in Ameloblastoma * Treatment * Conservative local excision or currettage * Reccurance is rare * Calcifying epithelial odontogenic tumor * Presentation / Progression * 30 - 50 yrs old * Mand \> Max * Chrcanovic 2017 * 90% Central * 10% Peripheral * Asymptomatic * Slow growing * Bony expansion * Imaging * Uni or multilocular * Variable calcification - fine flecks - Honeycombed appearance * Pathophysiology * Arises from Stratum intermedium of enamel organ * Associated with PTCH1 gene - Not associated with Gorlin Goltz Syndrome * Histology * Poorly encapsulated * Cystic spaces filled with amyloid like material * Apple green birefringence - Congo red stain * Polyhedral cells - Plump, pink eosinophilic cytoplasm * Spherical calcifications - Leisegang rings (Tree trunk rings) * Treatment * Locally aggressive * Conservative local resection with a narrow rim of surrounding bone * Currettage - Recurrence rate 15%

Answer 14

Benign Tumors - Mixed * Ameloblastic Fibroma * Presentation / Progression * True mixed tumors * \< 20 yrs old * M:F - 3:2 * Asymptomatic, Slow growing * Bony expansion * Mandibular molars, 70% posterior mandible * Most cases are associated with unerupted teeth * Imaging * Usually unilocular * Pathophysiology * Characterised by proliferation of both odontogenic epithelium and mesenchyme without hard tissue formation * Histology * Well encapsulated * Thin walled (1-2cells thick) * Cuboidal or columnar cells * Epithelium has two patterns * Long narrow cords in an anastamosing arrangement * Small, discrete islands that resemble follicular stage of devleoping enamel organ * May contain epithelial islands like ameloblastoma * Treatment * Less aggressive than ameloblastoma * More conservative as lesion tends to occur in kids * Excision with a rim of normal bone * Chrcanovic 2018 * Recurrence 20% * 50% change to ameloblastic fibrosarcoma - lifelong follow-up * Dentinogenic ghost cell tumor * Presentation / Progression * Solid variant of COC * More often Extraosseous than Intraosseous * Difficult to distinguish from COC radiographically * 50 yr old * Pathophysiology * Arises from epithelial remnant that were trapped within bone * Histology * Ameloblastomatous islands of epihelium in mature stroma * Have nests of ghost cells preent within epithelium - differentiates it from a peripheral ameloblastoma * Aberrant keratinisation may be found in the form of ghost cells with dysplastic dentine * Treatment * Can be aggressive - therefore wide local excision * Odontoma * Classification * Complex - Disorganised mass of enamel, dentine and cementum Usually occur posteriorly * Compound - Multiple denticles Usually occur in the maxilla * Presentation / Progression * Most common odontogenic tumor * \< 20 yrs old * Mand \> Max * Often replaces missing teeth * Pathophysiology * Harmatoma * Most simple form of a compound odontome is a supernumerary * Exact etiology unknown * Histology * Complex * Disorganised mass of enamel, dentine and cementum * Fibrous connective tissue capsule * Ghost cells may be present in 20% * Compound * Denticles present * Similar to complex but much more complete * Treatment * Primordial odontogenic tumor * Presentation / Progression * Very rare - 10 Case reports * Occurs in young patients * Asymptomatic swelling * Imaging * Well defined unilocular radiolucency * Pathophysiology * Unknown * Histology * Similar to ameloblastic fibroma * Single layer of columnar epithelium covering periphery of tumor resembles inner enamel epithelium with a core of dental papilla-like tissue * There is no signs of hard tissue formation * Treatment * Enucleate

Answer 15

Benign Tumors - Mesenchyme * Odontogenic Fibroma * Classification * Central * Peripheral * Appears like pyogenic granuloma * Histologically has odontogenic rests of epithelium * Presentation / Progression * 40 yrs of age * M:F - 1:2 * Most common sites are anterior maxilla and posterior mandible * Displaces teeth * Resorbs dentition * Imaging * Typically well defined unilocular radiolucency Larger lesions can be multilocular * Pathophysiology * Histology * 2 Types - Epithelium rich and Epithelium poor Does not affect behaviour or prognosis * Epithelium Rich * Non infiltrating connective tissue lesion resembling dental follicle * Stellate fibroblasts arranged in a whorled pattern * Fine collagen fibrils and considered ground substance * Epithelium Rich * Fairly cellular fibrous connective tissue * Varies from myxoid to densely hyalinised * Strands or nests of odontogenic epithelium * Focal deposits of ODAM (odontogenic ameloblast associated protein) * Treatment * Enucleation * Recurrence uncommon * Odontogenic Myxoma * Presentation / Progression * Benign locally aggressive * 30 yrs of age * F \> M * Mand \> Max - 2:1 * Teeth not displaced or resorbed * Imaging * Multilocular soap bubble appearance * Radiolucent wispy trabeculae * Scallops around teeth * Pathophysiology * Dervied from ectomesenchyme of tooth germ ro mesenchyme of jaw * Histology * Very cellular * Sparse stellate/spindle cells in myxoid/mucoid extracellular matrix Myxoid stroma contains: * GAGs, Hyaluronic acid and chondroitin sulfate * Poorly encapsulated * Myxoma cells have antibodies directed against vimentin (intermediate filament found in mesenchymal cells) * Treatment * Chrcanovic 2018 * Currettage - 30% * Enucleation - 13% * Enucleation + Peripheral ostectomy - 7% * Resection - 3% * Cemento-ossifying fibroma * Epidemiology * F\>M : 5:1 * 30 - 40 yrs of age * Mand \> Max * Pathophysiology * Associated with HRT2 mutation (Tumor suppressor gene) * Presentation / Progression * Asymptomatic lesion * Well defined lesion * Histology * Capsulated * Mainly avascular fibrous connective tissue with bits of woven bone and cementum like material * Small trabeculae with peripheral osteoid and osteoblastic rimming * Treatment * Enucleate if small and has not lost its capsule * Resect large/recurrent lesions affecting function - nose * 5mm margin * Associated pathology * Aneurysmal bone cyst occur within lesion * Cementoblastoma * Presentation / Progression * Only true neoplasm of cementum * Associated with tooth root - cf Osteoblastoma (Distinguishing feature is that the lesion is fused to the tooth root) * 10 - 20 yr olds * M \> F * 80% Mand * 50% lower 6s --\> lower 5s * Pain on palpation or biting * Vital tooth * Bony expansion * Imaging * Calcified opacity - Initially not calcified * Peripheral radiolucent zone * Mass blends with the root - no obvious root outline * Pathophysiology * Histology * Dentine like material * Irregularly placed lacunae and prominent reversal line * Mineralised material rimmed by cementoblasts * Fragments of cementum fuse at edges * Treatment * Continuous growth so need tooth removal * Root amputation and excision of mass + RCT * Chrcanovic 2017 - Recurrence rate 12%

Answer 16

* ADA Statement Paper 2020 * Definitions * Frenotomy / Frenulotomy * Division of frenum without suture or revision of remaining tissues * Frenuloplasty * Division of a frenum and closure of the mucosa with sutures * Frenectomy * Excision of frenum * Diagnosis * Needs both Functional Limitation + Anatomical Restriction * Function Limitation * Difficulty in breastfeeding * Speech impediment * Swallowing * Assessment * Hazelbaker * 0-14 scale (14 normal, \<11 function impaired) * Objective assessment whihc include both functional and appearance * Management Non-surgical management trailed first * Non-Surgical * Feeding positioning * Latch optimization * Nipple shields * Supply support * Speech path * Transition to solids * Speech * Patient education * Surgical Management * Frenotomy / Frenectomy * Cold steel * Recommended as lasers can include eye exposrue, inhalaton of smoke and aspiration of coolant * Contraindications * Orofacial malformations * Cleft palate * Pierre robin sequence * Bleeding disorders * Neuromuscular conditions * Vitamin K deficiency * Complications * Acute * Deep ulceration * Bleeding, Hematoma * Airway compromise * Swelling * Restricted tongue movement * Iatrogenic injury * Chronic * Recurrent ankyloglossia * Sub-mandibular salivary duct injury * Oral aversion * Ranula * Tongue paresthesia and infection

Answer 17

Langerhan Cell Histocytosis * Langerhan cell * Mononuclear cell of bone marrow origin that belongs to the dendritic cell family * Functions as an Antigen presenting cell * Lies within the basal layer of the epidermis * Histiocytosis * Two groups of immune cells - Macrophages and Dendritic cells * Epidemiology * 1-2 per million * Average age of presentation 25 yo old Peak incidence in below 4 years of oaage * The early the diagnosis - the poorer the outcome * Children below the age of 4 tend to have multi - have 4L * Classification * Single System * Uniforacl or Multifocal * Pathophysilogy * Unclear aetiology * * Multisystem

Answer 18

* Extracapsular dissection * Excision of lesion with a thin cuff of partoid tissue * Superficial Parotidectomy * Partial/Limited - Superficial parotidectomy but tracing some of the branches * Complete - Superficial parotidectomy but tracing all of the branches * Total Parotidectomy * Removing the whole gland but sparing the facial nerve * Radical Parotidectomy * Removal of the gland + Nerve * Extended Parotidectomy * Gland + Nerve + Other structures

Answer 19

* Spiro 1986 * MSK data over 35 yrs Retrospective rev of 2807 pts * Malignant Epidemiology * Minor glands 85% * Sublingual * Submandibular 50% * Parotid 25% * Pleomorphic Adenoma * 1.5% at 5 years * 9.5% at 10 - 15 years * Warthins Tumor - Papillary cystadenoma lymphomatosum * 0.1 - 0.5% of cases

Answer 20

* Biopsy * FNA * No evidence for tumor seeding after FNA * Schmidt 2011 * Meta analysis - 64 studies * Sensitivity * Neoplasm - 96% * Malignancy - 80% * Specificity * Neoplasm - 98% * Malignancy - 96% * Inadequacy rate * 8% * False negative * 21% * Limitations * Large variation in studies * Accuracy affected by experience of cytopathologists * Core Biopsy * Indications * Tissue architecture is required * Additional testing more accurate * Flow cytometry * Immunohistochemistry * Risks * Potential tumor spillage * Facial nerve injury - 0.2% * Scarring, Fistula, Hematoma * Schmidt 2011 * Sensitivity - 96% * Specificity - 99% * Inadequacy rate * 1% * False negative * 5% * When used in conjunction post FNA this decreases to 1% * Imaging * CT * Sensitivity - Close to 100% * Can detect a lesion but poor at distinguishing between benign vs malignant * Poor at identifying spread into adjacent tissue * Most useful at evaluating calcific lesions * MRI * Sensitivity - Close to 100% * Indications * Soft tissue and Neural invasion * Early bone marrow changes * Facial nerve localisation * 65% - Superficial to RMV * 15% - Deep to RMV * 10% - Entwined with RMV * Ultrasound * Indications * Monitoring * Can be useful in characterising the appearance and location of a lesion * Used in conjunction for FNA or Core Biopsy * Limited in assessing deep anatomical structures * Electromyography * Useful in evaluating perineural invasion by malignant tumors * Up to 40% of facial nerve can be affected without clinical weakness * Sialography * Useful in evaluating intra and extra ductal system * Limited role for evaluating autoimmune conditions given serum biomarkers * Previously used to differentiated between obstructive and autoimmune conditions * Blood Test * Autoimmune Screen * Rheumatoid Factor * ANA * Anti ss DNA - A (Anti-Ro) * Anti ss DNA - B (Anti-La) * ESR * IgG