Orofacial Cysts PDF

ODONTOGENIC CYSTS OF THE SOFT TISSUES A. ERUPTION CYST (Eruption Hematoma) The soft tissue variant of dentigerous cyst, surrounding the crown of a tooth that has erupted through the bone, but not the soft tissue Clinical presentation: Children Small fluctuant swelling on the alveolar ridge...

ODONTOGENIC CYSTS OF THE SOFT TISSUES A. ERUPTION CYST (Eruption Hematoma) The soft tissue variant of dentigerous cyst, surrounding the crown of a tooth that has erupted through the bone, but not the soft tissue Clinical presentation: Children Small fluctuant swelling on the alveolar ridge Translucent or blue ('eruption hematoma’) An erupting tooth on radiograph Treatment: o None; rupture spontaneously o Can un-roof cyst to facilitate eruption B. Gingival Cyst: Here’s the text with proper spacing: 1. ADULT The soft-tissue variant of lateral periodontal cyst Clinical presentation: - Adults - Facial gingiva of the mandibular canine-premolar area - Small, dome-shaped, translucent, fluctuant swelling Treatment: Surgical removal; no recurrence 2. NEWBORN Multiple small, nodular, keratin-filled, cystic lesions seen along the alveolar ridge of newborns or young infants Origin:** Odontogenic origin; remnants of dental lamina Clinical presentation: - Newborns or infants - Multiple, small, discrete, white nodules on the alveolar ridge Treatment: None required; rupture spontaneously within days 8 of 17  NON-ODONTOGENIC CYSTS 1. NON-ODONTOGENIC CYSTS OF THE JAWS A. NASOPALATINE DUCT CYST (Incisive Canal Cysts) Origin: Epithelial remnants of the nasopalatine duct Clinical presentation: The most common non-odontogenic cyst Peak age: 30-50 Midline of the anterior hard palate Can produce symptoms such as swelling, pain, pressure, or drainage Adjacent teeth are vital Radiographic features: Small, round or heart-shaped radiolucent area between and apical to the roots of the upper central incisors in the midline Size >6 mm (Average size of incisive foramen is 6 mm) Microscopic appearance: A cyst lined by stratified squamous or pseudostratified ciliated columnar epithelium Dense fibrous wall—contains neurovascular bundles and mucous glands Treatment: Enucleation B. Median Palatal Cyst* Origin: From the epithelium entrapped along the embryonic line of fusion of the lateral palatal shelves of the maxilla Clinical presentation: Rare fissural cyst Young adults Midline of the hard palate, posterior to the nasopalatine duct area Asymptomatic, some patients complain of pain or expansion Fluctuant swelling of the midline of the hard palate posterior to the palatine papilla Radiographic features: - Well-circumscribed radiolucency - Divergence of central incisors Microscopic appearance: - Lined by stratified squamous epithelium or pseudostratified ciliated columnar epithelium - Chronic inflammation may be seen in the wall Treatment: Surgical removal 9 of 17 2. NON-ODONTOGENIC CYSTS OF THE SOFT TISSUES A. INCISIVE PAPILLA CYST THE SOFT TISSUE VARIANT OF THE NASOPALATINE DUCT CYST B. MUCOUS RETENTION CYST (Salivary Duct Cyst / Retention Mucocele) Etiology: Ductal obstruction/Mucous plug Clinical presentation: Adults, 5th - 7th decades Location: FOM or buccal mucosa Small, translucent, soft dome- shaped swelling Microscopic appearance: A small cyst lined by ductal epithelium and filled with mucus Treatment: Surgical excision of cyst along with the adjacent minor salivary gland C. PALATAL CYSTS OF THE NEWBORN Multiple small, nodular, keratin-filled, cystic lesions seen on the posterior hard palate and soft palate of newborns or infants I. Epstein Pearls Derived from epithelium entrapped along the line of fusion of the palate during embryogenesis Found linearly along the mid-palatine raphe II. Bohn Nodules Derived from remnants of minor salivary glands epithelium Scattered along the junction of the hard and soft palate Clinical presentation: Common, 55% - 85% reported cases Small (1 – 3 mm), white/yellow papules Location: Most often at the junction between hard and soft palates They may occur in more anterior location along the raphe or on posterior palate lateral to the midline Frequently in clusters of 2 to 6 cysts, but single lesions can occur Microscopic appearance: Keratin-filled cystic cavity lined by stratified squamous epithelium Treatment: The epithelium degenerates or the cyst rupture onto the mucosal surface, eliminating its keratin content → No treatment is required 10 of 17 D.a DERMOID CYST Origin: Entrapped skin epithelium during embryonic development Clinical presentation: More children and young adults Most frequently in the midline of the floor of mouth region → Sublingual dermoid cyst large, doughy or rubbery intraoral swelling Normal or yellow-red color Lesions below the mylohyoid muscle cause "double chin” appearance Microscopic appearance: Cyst is lined by epidermis-like epithelium: Orthokeratinzed stratified squamous Dermal adnexal structures in the cyst wall: Hair follicles (F), sebaceous glands (S), and sweat glands Keratin debris and sebum in lumen Treatment: Surgical excision D.b EPIDERMOID CYST Similar to dermoid cysts of the oral cavity, lined by epidermis-like epithelium, but do NOT contain dermal appendages in the cyst wall E.a CERVICAL LYMPHOEPITHELIAL CYST (Branchial Cleft Cyst) Origin: Remnants of the second branchial arch Clinical presentation: More in young adults Location: lateral side of the neck, anterior to the sternocleidomastoid muscle Painless, compressible swelling Size: 1 to 10 cm in diameter Microscopic appearance: Cystic cavity lined by stratified squamous or pseudostratified ciliated columnar epithelium Lymphoid tissue is found in the cyst wall Germinal centers are usually present Treatment: Surgical excision E.b ORAL LYMPHOEPITHELIAL CYST Origin: Epithelium entrapped within tonsillar or accessory oral lymphoid tissue Clinical presentation: Any age, more in young adults More in the floor of the mouth, posterior lateral border of the tongue, and palatine tonsil Small, white or yellow, pearl-like submucosal nodule Microscopic appearance: Cystic cavity lined by stratified squamous epithelium Lymphoid tissue is found in the cyst wall Germinal centers are usually present Treatment: Surgical excision 11 of 17 F. NASOLABIAL CYST (Nasoalveolar Cyst / Klestadt Cyst) Origin: Epithelial remnants of the nasolacrimal duct Clinical presentation: Rare Fluctuant swelling in the upper lip close to the nasal-alar area Elevation of the ala of the nose Microscopic appearance: Pseudostratified ciliated columnar epithelial lining Treatment: Surgical excision G. THYROGLOSSAL DUCT CYST (Thyroglossal Tract Cyst) Thyroid gland begins as an invigation in foramen cecum and then descends inferiorly to its final position Thyroglossal duct normally atrophies and disappears Remnants of thyroglossal duct may persist anywhere along the migratory pathway of the thyroid gland, beginning at the foramen cecum → Cyst Clinical presentation: More in children and young adults Location: Typically located on the midline of the neck, anywhere along the thyroglossal tract 75% below hyoid bone May develop in the tongue Painless, fluctuant, movable swelling May move vertically when the patient protrudes the tongue or swallows Microscopic appearance: Cystic cavity lined by stratified squamous or pseudostratified ciliated columnar epithelium Thyroid tissue is usually found in the cyst wall Treatment: Surgical removal via a ‘Sistrunk’ procedure → Removal of the cyst, part of the hyoid, and muscular tissue along the tract to reduce recurrence PSEUDOCYSTS 12 of 17 PSEUDOCYSTS OF THE JAWS A. TRAUMATIC BONE CYST (Simple Bone Cyst / Solitary Bone Cyst) An empty or fluid-filled cavity that develops within bone Etiology: Many theories; arises from trauma causing intramedullary hemorrhage Clinical presentation: Children and teenagers (peak 10-20 years) Often an incidental radiographic finding in the mandible o Non-expansile Radiographic features: Non-expansile Mostly in mandibular premolar-molar area Radiolucency with characteristic scalloped superior margin Microscopic appearance: No epithelial lining Very little tissue is available: Fibrous tissue and small bone spicules Treatment: After exploration, most cysts will fill in with new bone formation and resolve over a period of 12-17 months B. STATIC BONE CYST (Stafne Bone Defect / Lingual Mandibular Salivary Gland Depression) Etiology: Developmental depression, Pressure from submandibular salivary gland or adipose tissue Clinical presentation: 90% in males, adults Asymptomatic Posterior mandible Radiographic features: Ovoid radiolucency Posterior mandible, below the IAN canal Microscopic appearance: Biopsy is usually unnecessary Normal submandibular gland tissue Some defects are devoid of tissue or contain muscle, blood vessels, fat, connective tissue, or lymphoid tissue Treatment: None, only recognition 13 of 17 C. ANEURYSMAL BONE CYST Pathogenesis: Unknown; haemodynamic disturbance in medullary bone? Clinical presentation: Rare in the jaws Children or young adultds Mandible (posterior part of the body or angle) Firm expensile swelling, causing facial deformity o May be associated with pain Radiographic features: Uni- or multilocular radiolucency Ballooned-out appearance due to gross cortical expansion Microscopic appearance: Numerous nonendothelial lined blood filled spaces of varying size, separated by cellular fibrous tissue Multinucleated giant cells Hemorrhage in fibrous septa Treatment: Curettage → Increased risk of bleeding, due to possibility of vascular malfortion → Managed in hospital 14 of 17 PSEUDOCYSTS OF THE SOFT TISSUES A. MUCOCELE (Extravasation Mucocele) Etiology: Trauma and damage to the duct → Extravasation of saliva Clinical presentation: More common than retention mucocele Children and young adults Soft, dome-shaped swelling Lower labial mucosa Bluish translucent color Microscopic appearance: Cyst-like cavity filled with mucus lined by inflamed granulation tissue (fibrous tissue and compressed macrophages) Treatment: Surgical excision → Should include removal of the feeding gland B. RANULA A variant of the extravasation mucocele that occurs in the floor of the mouth Etiology: Rupture of one of the multiple ducts of the sublingual gland → Mucin spillage Clinical presentation: More in children and young adults Exclusively in the floor of the mouth, lateral to the midline o Large, fluctuant, bluish, translucent swelling that resembles the swollen belly of a frog Microscopic appearance: Similar to mucocele, but larger in size Treatment: o Surgical excision + Removal of the associated sublingual gland o Marsupialization for large lesions 15 of 17 D. Antral cyst: 1. True cyst A. Surgical ciliated cyst / Postoperative maxillary cyst B. Sinus mucocele C. Retention cyst 2. Pseudocysts Surgical Ciliated Cyst (Post-operative maxillary cyst) An iatrogenic cyst develops as a result of surgery, involving the maxillary sinus Clinical presentation: Asymptomatic, or swelling and pain Pervious history of surgery in the maxillary bone Radiographic features: Well-circumscribed radiolucency in close proximity of the maxillary sinus Microscopic appearance: Cystic cavity lined by a pseudostratified ciliated columnar epithelium Treatment: Simple enucleation 16 of 17 Enucleation and Primary Closure 1. Mucoperiosteal flap 2. Window opened in bone 3. Soft tissue of cyst wall is seperated from the bony wall 4. Entire cyst is removed and sent for histological examination 5. The edges of the bone cavity is smoothed off, free bleeding is controlled, and the cavity is irrigated to remove debris 6. Mucoperiosteal flap is re-placed and sutures in place on sound bone around the margin of the bony window 7. Cavity will fill in blood and then organises 8. Sutures are left in place for at least 10 days Marsupialization 1. The cyst is opened 2. The lining is left in place and sutured to the oral mucous membrane at the margins of the opening to produce a wide communuication with the mouth, leading to decmpression of the cavity 3. The cavity must be kept clean by: Cavity is packed with ribbon guaze Food debris has to be washed out regularly 4. The cavity gradually closes by ingrowth of bone and oral epithelium 5. The openig will shrink with healing 6. When the cyst has shrunk and enough new bone has formed, the remainig lining can be enucleated MALIGNANCY Rare Possibility of it representing metastatic spread must be ruled out Mostly arising in odontogenic cysts: 1% - 2% of all oral cavity carcinomas Cysts with malignancy potential: 1. Residual periapical cyst (60% of reported cases) 2. Dentigerous cyst (16% of reported cases) 3. Some were from ( lateral periodontal cyst, OKC, & orthokeratinzed odontogenic cyst) Clinical presentation: Wide age range, mostly in older patients (mean age of 60 years old) More common in men Pain and swelling, however it could be asymptomatic Radiographic features: May mimic odontogenic cyst, but the margins of the radiolucent lesion are usually irregular and ragged Microscopic appearance: Well defined or moderately differentiated squamous cell carcinoma Treatment: Local block excision Radical resection +/- radiation or chemotherapy 17 of 17