Cysts Notes PDF

Notes by : Ebtesam Kaki Mohammed Nadershah MD, BDS, MSc Associate Professor & Consultant Maxillofacial Surgeon Diplomat of The American Board of OMS What is a Cyst?  A pathologic cavity that is lined by epithelium  Odontogenic  from a tooth-related apparatus  How Do...

Notes by : Ebtesam Kaki Mohammed Nadershah MD, BDS, MSc Associate Professor & Consultant Maxillofacial Surgeon Diplomat of The American Board of OMS What is a Cyst?  A pathologic cavity that is lined by epithelium  Odontogenic  from a tooth-related apparatus  How Does a Cyst form? Odontogenesis Dental Lamina  Enamel organ Remnant of DL Epithelial rests of Malassez  PA cyst Dental follicle Dental papilla Why a cyst keeps growing in size? Its a cycle of degradation of internal lining of the cavity The degradation will increase the osmotic pressure which cause fluids to diffuse into the cells and so it grows Then new lining sheds so more pressure = more growth (continuous process) This is important to understand because one of the techniques of management is marspulaiztion (decompression) Continued increased osmotic pressure growth  More common Odontogenic Cysts What is the difference between  Developmental Cysts inflammatory and developmental cysts? Clinically : vitality of tooth if not vital then inflammatory  Inflammatory Cysts Non-Odontogenic Cysts Inflammatory cysts are mine common Its imortant o know because it helps with differential diagnosis  Dentigerous Cyst (Follicular cysts)  “Dentigerous“ = containing tooth.  Follicular = cyst surrounds the crown of an unerupted tooth. & Very common developmental  Attaches to the neck of the tooth. cyst attaches to CEJ  Represents 15-17% of all cysts of the jaws.  Etiology and Pathogenesis How it develops ↳  Cystic change of the reduced enamel epithelium after complete formation of enamel of the tooth. Mechanism of growth ↳  Accumulation of fluid between the reduced enamel epithelium and the crown.  Clinical Features Types of dentigerous cyst 1-  Age: most frequently in children and young adults  Sex: slight male predilection  Site: lower 8, upper 3  Uncomplicated dentigerous cysts cause no symptoms and may be discovered accidentally.  Can be confused with enlarged follicle (>5 mm). When is it a follicle when is it a cyst? If more than 5 mm its a cyst  Complications As the cyst grows, it can cause - Bone resorption & / or expansion - Facial asymmetry - Displacement of teeth - Resorption of roots of adjacent teeth - If infected  pain and increased swelling  Radiographic Features Because its slow growing  Well-defined Corticated  Unilocular radiolucency, sclerotic margin &  In association with the crown of an unerupted tooth  The tooth may be forced in a direction opposite to its normal eruptive movement Types of detegirous cyst Central : most common But in all types it attaches to CEJ Central Circumferential & Lateral The tooth is within the cyst  Because of the serious complications it shouldn’t be ignored even if it isn’t growing Complications Most commonly becomes T 1- Transformation into an ameloblasloma. Less likely but still happens 2- Carcinomatous transformation. 3- Destruction of a large area of the jaw with possible fracture.  Soft tissue center part of dentigerous cyst Eruption Cyst Its self limiting will go away when tooth erupts Typically happens to children  It is an uncommon superficial dentigerous cyst occurring in the soft tissue of the gingiva or alveolar mucosa over a tooth about to erupt.  It is dilatation of the normal follicular space above the crown of an erupting tooth caused by accumulation of tissue fluid or blood.  Clinically  Age: children and young adults (deciduous teeth or permanent molars)  Site: Gingiva overlying the unerupted tooth.  Shape: Soft rounded swelling if blood is present in the cystic space, the swelling appears deep blue & hence the term "eruption haematoma” Some times it appears bluish because of blood acclamation if it takes to long to g away we might incise it  Odontogenic Keratocyst (OKC)  Sporadic or part of the Nevoid Basal Cell Ca syndrome  Derived from remnants of the dental lamina  More aggressive than other odontogenic cysts  Has a higher rate of recurrence Because of daughter cysts / easily ruptured during removal because of thin lining classified as tumor (KCOT) 2005  Cyst 2017  Clinical Features  Age: mostly between 10-4o years  Sex: slight male predilection  Site: posterior Mandible  Radiographic: unilocular or multilocular  Histopathology Thin lining  Stratified squamous epithelium, 6-8 cells in thickness.  Parakeratotic surface, corrugated.  Thin and friable wall  Epithelial budding  Daughter cysts. Enlarged head circumference Calcified Falx cerbri * Fa Increased eye distance &  Lateral Periodontal Cyst Non-inflammatory developmental cyst which * occurs adjacent or lateral to the root of a vital tooth.  Etiology and Pathogenesis  The origin is related to proliferation of rests of Malassez within the bone.  Clinical features  Age: any age, mostly >21 y  Sex: Male to female ratio 2:1.  Site: mandibular premolar - canine region, upper lateral incisor. Sometimes we can see a bulge or swelling next to the tooth  Lateral Periodontal Cyst  Often asymptomatic and maybe discovered during routine RG examination.  Occasionally, when the cyst is located on the labial surface of the root, there may be a slight bulge  Overlying mucosa is normal.  The related tooth is vital.  Radiographic Features  Lateral periodontal cyst appears as a radiolucent area.  Small, seldom over 1cm in diameter.  May or may not be well circumscribed with an opaque margin.  Soft tissue counterpart of lateral periodontal cyst Gingival Cysts Non-inflammatory developmental cyst developing adjacent to a vital tooth. Types: -gingival cysts of adults -gingival cysts of newborn (dental lamina cysts, congenital keratotic cyst, Bohn’s nodules)  Etiology and Pathogenesis  Gingival cysts arise from dental lamina remnants in the soft tissue between the oral epithelium and the periosteum.  Gingival Cysts of Adults  Age: any age, most commonly 40-60 y  Sex: males = females  Well-circumscribed,  painless  < 1 cm in diameter  Free or attached gingiva  Normal color Because it puts pressure on bone  Larger lesions may erode bone bluish discoloration  Soft tissue counterpart of lateral PD cyst  Radiographic Features Gingival cyst of the adult soft tissue lesion  -ve RG Doesn’t show on radiographs  Gingival Cyst of The Newborn  Multiple white nodules, few mm in diameter, on the alveolar ridge of a new born  Remnants of the dental lamina  Asymptomatic.  In most cases degenerate, rupture and resolve spontaneously within the first 3 months of life  tx: reassurance  Epsteins’ pearl on mid palate Calcifying Odontogenic Cyst (COC)  Age: any age, teenage years  Sex: F > M  Site: Maxilla > Mandible  Low recurrence potential  Early RL  Mixed ROp-RL  Extraosseous 25% Has 3 phases  Tx: Enucleation Radiolucent Mixed Opaque Glandular Odontogenic Cyst (Sialo- Odontogenic Cyst)  Rare and recently described developmental jaw cyst  May resemble a central mucoepidermoid carcinoma  locally aggressive behaviour We need to do a biopsy and review the results again because the management for both diseases are different  Recurrence potential. Glandular Odontogenic Cyst, typical scalloped appearance. Because it grows fast and more aggressive and so such cyst will look scalloped or with I’ll defined margins BOTRYOID ODONTOGENIC CYST  Intra-osseous lesion  Macroscopic and microscopic multilocular growth pattern  Resembling a bunch of grapes  BOC  A developmental cyst of odontogenic epithelial origin.  Considered as a rare multilocular variety of lateral periodontal cyst.  The cystic lesion occurs in the periodontal space of vital teeth.  Clinical Features  The lesion is mostly located in the mandible, mainly the anterior region, but may also occur in the anterior maxilla  Several cases of multiple recurrences have been reported up to nine years after the initial surgery.  Radiographic Features  Unilocular or multilocular radiolucencies. Cysts of Inflammatory Origin  Radicular cyst  The most common cyst (65% of all cysts).  Inflammatory hyperplasia of the epithelial rests of Malassez in PDL  Periapical (related to root apex)  Lateral (related to accessory root canal)  Residual after extraction in edentulous area.  Clinical Appearance Age: Adult life (third to the sixth decades) Sex: M>F Site: Maxilla especially the anterior region. There is usually a non-vital tooth Most are asymptomatic and are discovered during routine dental radiographic examination. Symptoms may develop if infected  RG Features Slow growing  Round or ovoid well-defined radiolucency.  Narrow radio-opaque margin which may not be apparent if the cyst is actively enlarging.  The cyst ranges from 5mm to several cm in diameter  Root resorption of the offending tooth or adjacent teeth may be noted.  Large cyst in the maxilla may extend in any direction and become irregular in shape.  Infection of a cyst causes the outline to become hazy.  Distinction between a small radicular cyst and Collection of granulation tissue a periapical granuloma radiographically is difficult. The difference between them is important to know because granuloma will go away if we do RCT but a cyst will need a different management More than 5mm its most probably a cyst In treatment we have to solve the cause of the problem so extract the tooth or treat it  Residual Cyst Could result in a denture not fitting because it happened after extraction  The necrotic tooth from which a periapical cyst has developed may be extracted and the cyst may persist.  A common causes of swelling of the edentulous jaw.  Complications of residual cysts: - Interfere with the fitness of dentures - Weakening the jaw with possible risk of jaw fracture. Inflammatory Periodontal Cyst  It originates in the vicinity of the neck of the tooth as a result of an inflammatory process in a periodontal pocket.  Frequent periodontal is common when there is a lack of space.  Non-odontogenic Cysts These are cysts arising from non-odontogenic epithelium in the jaws or in the oral cavity and related structures.  Nasopalatine Canal (Duct) Cyst  Nasolabial Cyst  Soft tissue cysts of the jaw and neck Dermoid and epidermoid cysts Thyroglossal tract cyst Benign lymphoepithelial cyst (branchial-cleft cyst) Mucous retention cyst  Cysts of salivary gland Mucous retention cyst Mucous extravasation cyst  Pseudocysts Traumatic bone cyst Aneurysmal bone cyst Static bone cyst Mucous extravasation cyst Nasopalatine Canal (Duct) Cyst  Intraosseous developmental cyst of the midline of the anterior palate.  The most common developmental, -- epithelial, and non-odontogenic cysts of the oral cavity -  May develop from the epithelial remnants of the oro-nasal ducts within the incisive canals Heart shaped in radiographs because of the anterior nasal spine postion  Clinical Features  Age: 30-60 y  Sex: M>F, 2 : 1  Usually asymptomatic unless secondarily infected.  They may open by a tiny fistula near the palatine papilla  The teeth in the area are vital; in edentulous patients denture pressure may cause a typical neuralgia.  Radiographic Features  Round or heart-shaped radiolucency in the midline  There may be superimposition of the ANS  The radiolucency appears to be bilaterally symmetrical. We might think its just the incisive canal so just wait and see if it grows in size  Small cysts may be indistinguishable from a somewhat large incisive foramen, which may reach 6 mm in width.  Nasolabial Cyst Soft tissue cyst so no radiographic evidence unless it causes bon resorption  The nasolabial (nasoalveolar) cyst is not found within bone.  Previously called golobulomaxillary and thought to be due to entrapped epithelium along the junction of lateral nasal and maxillary process.  Recently, originate from nasolacrimal duct nasal epithelium rests.  Clinical Features  F>M  It may encroaches on the nasal cavity.  May become palpable from the labial vestibule.  May raise the alar cartilage and obliterate the NLF  Radiographic Features  R,G findings are negative  It may produce pressure resorption of the underlying bone,  distortion of the inferior margin of the anterior nasal opening.  Traumatic bone cyst So its a pseudo cyst  Lacks an epithelial lining  Cannot be classified as a true cyst.  Often no fluid content.  Pathogenesis  Usually associated with mild trauma to the jaw that causes bleeding and haematoma formation within bone  dissolution of the clot  Steady expansion of the lesion occurs until cortical It travels within the bone marrow? So it doesn’t cause expansion of the bone is reached. bone until it reaches cortical bone then the growth stops  Clinical Features  Age: F More common for trauma  Site: Mandible molar - premolar region. occurs in long bones more common than in jaws.  Most cases are asymptomatic, discovered accidentally  Does not cause expansion of the cortical bone in most cases; swelling of the jaws is seen in only 25% of cases.  Teeth associated with the cyst retain their vitality are not often loosened.  Radiographic Appearance  The cyst varies in size and may extend from the body of the mandible into the ramus. If its below the IAC that’s stafine bone cyst  Above the inferior alveolar canal, well demarcated unilocular  May project into the inter-radicular septa and produce a scalloped contour between the roots.  In the anterior region, the outline is usually regular, round or oval in shape with no indentations between the teeth.  Roots of adjacent teeth may be displaced but they are not resorbed nor do they become devitalized.  ANEURYSMAL BONE CYST  Classified as a pseudocyst because it appears radiographically as a cyst-like lesion but microscopically exhibits no epithelial lining.  Clinical Appearance  Age: between 6 and 17 years.  Sex: no predilection  Site: mandibular molar areas.  Appearance: often painful and tender.  At Surgery, excessive bleeding is encountered resembling a blood-soaked sponge.  Radiographic Features Aggressive cyst  Multilocular radiolucency with a honeycomb or soap-bubble appearance.  Teeth may be displaced with or without root resorption.  STATIC BONE CYST (Stafne bone cyst, Latent bone cyst, Submandibular Salivary Gland Depression Cyst)  Not a true cyst as it has no epithelial lining, but appears cystic or radiolucent area on radiographic examination.  It is considered as a cyst-like lesion.  Radiographic Features  Round to ovoid, sharply circumscribed radiolucency with or without a radiopaque margin.  Below the level of the inferior dental canal.  The lesion is constant in size and shape in the same patient and hence the name static.  Sialogram may confirm the diagnosis  Epidermoid Cyst (Sebaceous Cyst)  Any part of the facial skin or neck  Most common in the midcheek and preauricular area.  80% painless, solitary masses, 20% painful because of secondary infection.  Freely movable within the skin, some are fixed because of fibrosis from Repeated infections.  Originate from hair follicle epithelium.  Epidermoid Cyst  Treatment require surgical excision.  Dermoid Cyst  Only 2% occur in head and neck area Mostly also happens in the ovaries and its a teratoma  Can occur in the midline below or above the mylohyoid muscle If above mylohyoid you will see it under the tongue If below you will see it under the mandible  Painless  Compressible Teratoma  The wall contains skin appendages  Tx: excision  Clinical Features Diagnosis  Moves with swallowing  Doughy, smooth, tender if infected  Age: most commonly in the 20s  FNA  cystic fluid  Tx: Sistrunk procedure ↳ Incision of cyst and anterior part and central part of hyoid bone  Branchial Cleft Cysts Rapidly arising swelling in the lateral neck Usually preceded by URI Age: teenage or young adults Dx by FNA, CT, HP  Salivary Retention/ Extravasation phenomena  Trauma or blockage to the SG duct  Minor SG  mucocele (Lower lip)  Sublingual gland  ranula (FOM)  Parotid / SM gland  Sialocele  Excise and remove minor SG involved Mucocele Ranula Plunging Ranula If its below the mylohyoid How to manage a Radiolucent lesion? * First do vitality test before even aspiration it’s non invasive and will remove half of the differential list ① Aspiration:  First  ALWAYS ASPIRATE If yellow (cyst) Blood (auorysmal cyst or vascular tumors) If cyst  straw-colored fluid Nothing (pseudo cyst or traumatic bone cyst) Nothing + no cavity + solid mass ( tumor)  Incisional vs excisional biopsy Depending on size if large excise Cysts of the jaws are treated in one of the following methods: Enucleation Scope out and remove the lining ex: dentigerous cyst Remove the lining + extra step of removing bone done if there is high Curretage reoccurrence rate ex: OKC, glandular Odontogenic cyst Marsupialization Combination Shelling-out of the entire cystic lesion without rupture. - & Should be performed with care, in attempt to remove the cyst in one piece without fragmentation, which reduce the chances of recurrence.  The incision through the mucosa should not lie directly over the cyst lumen (wound healing problems). The Cyst is usually approached from the area with the thinnest bone.  the concave surface of the curette should be kept facing the bone. The edge of the convex surface performs the stripping of the cyst. Care must be exercised to avoid tearing the cyst and allowing the cystic contents to escape, why? 1. Margins of the cyst is easier to define if the cystic wall is intact. 2. The cyst separates more readily from the bony cavity when the intra-cystic pressure is maintained.  Avoid injury to neurovascular structures in large cysts as nerves and vessels are usually pushed to one side of the cavity by slowly expanding cyst. Once the cyst has been removed, the bony cavity should be inspected for remnants of the tissue. Irrigation and drying the cavity with gauze will aid in visualization the entire bony cavity. Residual tissue is removed with curettes. The bony edges should be smoothed with file before closure.  Used with large lesions that if we removed it it will cause too much trouble ex; its close to vital structures Patient is medically compromised can’t tolerate surgery Cause too much distruction decompression - by creating a surgical window in the wall of the cyst, evacuating the contents of the cyst, and maintaining continuity between the cyst and the oral cavity. The only portion of the cyst that is removed is the piece to produce the window and remaining cystic lining is left in situ. This process decreases intra-cystic pressure and promotes shrinkage of the cyst and bone deposition. O 1. Amount of tissue injury. Proximity of a cyst to vital structures O2. Surgical access. If access to all portions of the cyst is difficult. O 3. Assistance in eruption of teeth.  4. Extent of surgery. In an unhealthy or debilitated patient, ⑧ marsupialization is a reasonable alternative to enucleation,. O during enucleation is possible. 5. Size of cyst. In very large cysts, a risk of jaw fracture  Advantages: 1. O Simple. 2. Avoid damaging nerves. O 3. Avoid pathological fracture. ① Disadvantages: We will leave pathological lining that might be a different diagnosis than the rest of the lesion ↳ ⑧ 1. Leaves pathological tissue (a more aggressive lesion may be present in the residual tissue). ⑧ 2. Needs great compliance (pt need to wear obturator for long periods of time).- Could need more than 6 m + pt is left with a whole on his mouth - 3. O Inconvenience for patient Hygiene demands (bad OH can cause bad smell of the mouth).  Prophylactic antibiotics are not usually indicated in marsupialization.  If the aspirate suspect the diagnosis of a cyst, the marsupialization procedure may proceed.  The initial incision is usually circular or elliptic and creates a large (1 cm or larger) window into the cystic cavity.  If the bone has been expanded and thinned by the cyst, the initial incision may extend through the bone into the cystic cavity.  If the overlying bone is thick, an osseous window is removed carefully with burs and rongeurs.  The cyst is then incised to remove a window of the lining, which is submitted for pathologic examination.  Areas of ulceration or thickening of the cystic wall should alert the clinician to the possibility of dysplastic or neoplastic changes in the wall of the cyst. In this instance enueleation of the entire cyst or incisional biopsy of the suspicious area or areas should be done. If the cystic lining is thick enough, the perimeter of the cystic wall around the window can be sutured to the oral mucosa. Otherwise, the cavity should be packed with strip gauze impregnated with antibiotic ointment. This packing must be left in place for 10 to 14 days to prevent the oral mucosa from healing over the cystic window. By 2 weeks the lining of the cyst should be healed to the oral mucosa around the periphery of the window.  Careful instructions to the patient regarding cleaning of the cavity are necessary  Curettage  After enucleation  Types: 1- mechanical  rotary instruments 2- thermal  cryotherapy 3- chemical  carnoy’s solution Not used anymore because With high recurrence  Recommended for aggressive cysts like OKC Questions?