Gingival Cysts in Adults

Gingival Cyst of Adults

• Proposed origins: odontogenic epithelial cell rests, traumatic implantation of surface epithelium, or cystic degeneration of deep surface epithelium projections.

Clinical Features (Gingival Cyst of Adults)

• Age: 5th to 6th decade of life
• Gender: Equally affects males and females
• Site: Mandible, canine and premolar area; attached gingiva or interdental papilla
• Signs and Symptoms: Slow, painless, well-circumscribed enlargement, swelling on the facial aspect of free/attached gingiva. Smooth, normal-colored surface; fluctuant, adjacent teeth vital. Less than 1cm in diameter.

Radiological Features (Gingival Cyst of Adults)

• No significant radiographic changes are typically seen.
• A faint radiographic shadow suggestive of superficial bone erosion might be present.

Histology (Gingival Cyst of Adults)

• Histological features similar to lateral periodontal cysts.
• Lining typically thin, flattened stratified squamous epithelium.
• Possible focal thickenings (plaques) within the lining.
• Epithelial lining contiguous with the junctional epithelium of an adjacent tooth.

Gingival Cyst of Infants

• Also known as Bohn's Nodules, Epstein's pearls, or Dental lamina cysts of the newborn.
• Originates from remnants of the dental lamina, which proliferate to form small keratinizing cysts.
• Typically present as multiple nodules along the alveolar ridge in neonates.
• Fragments of dental lamina remaining in the alveolar ridge mucosa after tooth formation proliferate.
• Asymptomatic, white nodules commonly found on the upper alveolar ridge of newborn infants.
• Originates from epithelial rests of Serres within the gingivae.

Epstein's Pearls

• Similar small cysts along the midpalatine raphe in newborns.
• May enlarge slightly to appear as creamy-colored swellings (few millimeters in diameter), but resolve spontaneously within weeks/months.
• Small keratin-filled cysts at the junction of the hard and soft palates in newborn infants
• Dental Lamina Cyst, distributed on the alveolar ridges in newborns

Histology (Gingival Cysts of the Newborn)

• Histologically lined by a bland stratified squamous epithelium.
• No detectable radiographic changes.
• Resolves spontaneously due to deciduous tooth eruption, usually no treatment needed.

Lateral Periodontal Cyst

• Non-inflammatory developmental cyst that occurs laterally to the root of a vital tooth.
• Non-keratinized developmental cyst.
• Needs distinction from a lateral radicular cyst (associated with a non-vital tooth) and odontogenic keratocysts arising next to the tooth root.
• Gingival cysts of the adult are histologically and pathologically similar.
• Originates from the epithelial rests of Malassez within the lateral periodontal ligament.

Clinical Features (Lateral Periodontal Cyst)

• Age: 20-60 years, peak incidence in the 6th decade.
• Sex: Males more commonly affected.
• Site: Primary occurrence in the canine and premolar region of the mandible, and lateral incisor region of the maxilla.
• Symptoms: Usually asymptomatic; occasionally pain and swelling on the lateral aspect of the tooth root can occur.

Radiological Features (Lateral Periodontal Cyst)

• Round to ovoid, unilocular radiolucent area with sclerotic margins.
• Typically located between adjacent roots. Rarely at root divergence.
• Located between the cervical margin and the root apex.
• Distinguishing from collateral OKC radiographically possible when multilocular.
• Well-corticated margins suggestive of slow enlargement observed in radiographs.
• Radiolucent lesion between the roots of a vital mandibular canine and first premolar

Histological Features (Lateral Periodontal Cyst)

• Lined by thin, non-keratinized squamous or cuboidal epithelium (1-5 cell layers).
• Exhibits focal plaque-like thickenings resembling reduced enamel epithelium.
• Underlying connective tissue lacks chronic inflammatory cells.
• Lumen usually a hollow sac.

Calcifying Odontogenic Cyst (Gorlin Cyst)

• Also known as an odontogenic ghost cell cyst or Gorlin cyst.
• Odontogenic lesion with mixed features of a cyst and solid neoplasm.
• Unicystic process originating from reduced dental epithelium or dental lamina remnants.
• Lining has the potential to induce dentinoid or even odontoma formation sometimes within adjacent connective tissue.

Clinical Features (Calcifying Odontogenic Cyst)

• Age: Wide range, peak in 2nd decade.
• Sex: Equally affected.
• Site: Anterior segment of both jaws.
• Symptoms: Swelling most common complaint; seldom associated with pain. Occasionally, facial asymmetry (due to hard bony expansion), or tooth displacement can occur.

Radiological Features (Calcifying Odontogenic Cyst)

• Well-defined, commonly unilocular radiolucency.
• Irregular calcified masses of varying sizes often within the lucency.
• Displacement of roots observed with or without resorption; cortical plate expansion may be observed.
• Radiographic image of calcifying odontogenic cyst of the maxilla typically show well-defined margins and calcification may be observed.

Histological Features (Calcifying Odontogenic Cyst)

• Thin lining (typically 6-8 cells), but can be thicker at various sites.
• Lining exhibits characteristic odontogenic features.
• Reversely polarized basal cell layer commonly observed.
• Presence of ghost cells (enlarged, eosinophilic cells with well-defined borders) sometimes seen in thickened areas of the cyst lining.
• Cells may occasionally fuse.
• Frequent calcification, and occasionally tubular dentinoid or complex odontome formation within connective tissue close to lining.
• Sheets of ghost cells and focal calcifications noted in stratified squamous epithelium.
• Induction of a strip of dysplastic dentine (dentinoid) in the connective tissue area.

Glandular Odontogenic Cyst

• Rare odontogenic cyst also called sialo-odontogenic cyst.
• Diagnosed primarily in middle-aged patients.
• Involves the mandible, often anterior to molars.
• Painless, and is unilocular or multilocular expansion of the jaw. - Can cause displacement and resorption of teeth.

Radiographic Features (Glandular Odontogenic Cyst)

• Radiographic margins could be well-defined and sclerotic, or more aggressive lesions indicate ill-defined peripheral borders.
• Presents in variations in size - can be less than 1cm to involve jaw bilaterally.

Histopathology (Glandular Odontogenic Cyst)

• Lined by epithelium varying in thickness, a superficial layer of columnar or cuboidal cells present.
• Composed of small glands lined by mucous cells secreting mucin. Epithelial lining thickenings present.

Botryoid Odontogenic Cysts

• Rare variant of the lateral periodontal cyst, characterized by multilocular structure.

• Commonly found in mandibular premolar to canine areas, affecting those over 50. Tendency to recur.

• Easily mistaken for odontogenic keratocysts.

• Multilocularity features not always readily identifiable in radiographic images.

• Corticated (well-defined), scalloped outlines may indicate possible multilocularity in radiologic imaging, but no other clear distinguishing cyst characteristic may be present.

• Often indistinguishable from lateral periodontal cyst histologically, featuring similar appearances, however, multiple cyst cavities are distinctly different from a single cyst cavity.

Radicular Cyst

• Inflammatory preapical periodontal cyst (subdivided into apical, lateral and residual types).
• Apical radicular cysts most common cystic lesion in jaws.
• Always associated with non-vital teeth and located around the apical foramen.
• Develops as inflammatory hyperplasia of Malassez cells, and often follows pulp necrosis.

Pathogenesis (Radicular Cysts)

• Originates from inflammatory hyperplasia of the epithelial rests of Malassez within the apical periodontal ligament, often after pulp necrosis.
• Necrotic debris from dead pulp can incite apical bone inflammation.
• This then leads to granuloma formation, composed of inflammatory cells, granulation tissue, scar.
• This stimulates epithelial proliferation and the formation of periapical cysts.
• Periapical cysts walls separate the pulpal irritation from the bone.

Clinical Features (Radicular Cysts)

• Age: Peak incidence in 3rd, 4th, and 5th decades.
• Sex: More common in males.
• Site: Maxillary anterior region, often for non-vital teeth; less common mandibular area.
• Symptoms: Progresses slowly and presents with painless swelling. Symptomatic only when cyst size increases substantially. Swelling is commonly rounded and initially hard, and progresses to a fluctuant swelling.

Radiological Features (Radicular Cysts)

• Round to ovoid (heart-shaped), unilocular radiolucency.
• Typically noted above the roots of maxillary central incisors.
• Sclerotic borders, possible root displacement, or root resorption. (or expansion of cortical plate).
• Can sometimes cause tooth separation or displacement.

Histological Features (Radicular Cysts)

• Non-keratinized, varying-thickness epithelium noted.
• Inflammatory cells (lymphocytes, macrophages, plasma cells) are present in the connective tissue wall.
• Hyaline and/or Rushton bodies in the epithelium or connective tissues.
• Cholesterol crystals within clefts of connective tissues are occasionally present.
• Epithelium sometimes appears net-like (ring formations, arcades) in more inflamed cysts.
• Presence of mucous cells, indicating potential metaplasia within the tissues.
• Quiescent epithelium present, particularly in long-standing cases.
• Mucous cells sometimes noted in surface layer of stratified squamous epithelium.
• Hyaline bodies present in epithelial lining.
• Mural nodules of cholesterol-containing granulation tissue exhibiting into the cyst cavity occasionally observed.

Residual and Lateral Radicular Cysts

• Residual radicular cysts: Persists after tooth extraction.
• Lateral radicular cysts: Develop from non-vital tooth lateral root canals, instead of the apex.
• Differentiation from lateral periodontal cysts is crucial due to different origins and potential behaviors.

Nasopalatine Duct Cyst.

• Common non-odontogenic cyst arising in the nasopalatine canal (nasopalatine duct).
• Developmental origin thought to originate from residual embryonic epithelial remnants.
• Develops due to trauma, or bacterial or viral infections of the nasopalatine canal lining.
• May occur at various locations along the nasopalatine canal, often within lower portion.
• Asymptomatic, or present with a salty fluid discharge.
• Pain occasionally associated with inflammation or pressure on the nasopalatine nerves.
• Possible differentiation from periapical cysts through assessing tooth vitality.
• Radiographic images often show a well-circumscribed radiolucency, round, ovoid or heart-shaped near maxillary central incisor roots (sometimes separating them)
• Often lined by stratified squamous epithelium or pseudostratified, ciliated columnar epithelium with inflammatory cells, mucous glands, and mucoid material in the lumen. (Epithelial layers can vary in thickness).
• Can occasionally present within soft palate tissue alongside the palatine papillae.
• Presents as superficial bluish swelling, discharging a salty fluid. No radiographic changes are expected.

Nasolabial Cyst

• Rare lesion found in upper lip soft tissue, below alar area. - Considered to arise as a fissural cyst formed at nasal and maxillary processes during development. Likely origination from embryologic remnants of the nasolacrimal duct.
• Clinically, presents as a slow-enlarging soft-tissue swelling.
• Typically involves the nasolabial fold, causing nasal breathing difficulties and occasionally pain or tenderness (if inflameed).
• May cause extra-oral changes such as nasal ala elevation, and/or intra-oral swelling along the labial sulcus.
• Radiographic presence generally exhibits no visible changes, but pressure from the cyst causes punched-out appearance of radiolucent area, seen along side the anterior maxillary aspect, in some cases.
• Cyst lining comprised of pseudostratified, ciliated columnar or stratified squamous epithelium that can contain mucous cells. (Epithelial layer thickness can often vary).

Median Cysts

• Rare cysts in the palate/mandible; uncertain origin and status.
• Epithelium trapped during developmental fusion of palatal elements.
• Radiographically appear as a well-circumscribed radiolucency.
• Histologically lined with a stratified squamous epithelium overlying dense fibrous connective tissue.

This quiz explores key aspects of gingival cysts in adults, including their common age range, associated sites, and characteristic features. Additionally, it delves into the vitality of adjacent teeth and the proposed origins of these cysts. Test your knowledge and understanding of this dental condition.