Mandible / maxilla
Odontogenic cysts
General

Author: Annie Morrison, M.D. (see Authors page)
Editor: Kelly R. Magliocca, D.D.S., M.P.H.

Revised: 21 June 2018, last major update May 2018

Copyright: (c) 2004-2018, PathologyOutlines.com, Inc.

PubMed Search: Odontogenic cyst [title] mandible maxilla

Cite this page: Morrison, A. Odontogenic cysts: general. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/mandiblemaxillaodontogeniccyst.html. Accessed September 25th, 2018.
Definition / general
  • Oral cavity cysts exist in jaw bones and soft tissue, including gingiva
  • Odontogenic: arise from tissues involved in tooth formation
  • In jaw, cysts are either odontogenic or non-odontogenic in origin
Terminology
  • Jaw / gnathic bones are maxilla and mandible; pathology is termed intra-osseous / central
  • Pathology within oral soft tissue is termed extra-osseous / peripheral
  • Odontogenic cyst: heterogenous group of lesions, classified into three groups:
    • Inflammatory, such as periapical / radicular cyst
    • Developmental, such as lateral periodontal cyst
    • Neoplastic, such as keratocystic odontogenic tumor
  • Non-odontogenic cyst: also heterogenous group of lesions, such as nasopalatine duct cyst
Epidemiology
  • Most common odontogenic cyst is periapical / radicular cyst (inflammatory cyst), followed by dentigerous cyst, which is usually considered developmental but can arise from inflammation (J Investig Clin Dent 2014;5:9)
Sites
  • Odontogenic cyst, inflammatory: originate in tooth bearing areas of maxilla and mandible; precise location depends on cyst type
  • Odontogenic cyst, developmental or neoplastic: variable location within maxilla or mandible depending on cyst type
Etiology
  • Teeth develop from bud-like invagination of ectodermal lining of primitive oral cavity epithelium
  • Through various complex interactions, dental lamina guides tooth bud formation for primary (deciduous / baby) teeth and permanent (succedaneous / adult) teeth
  • Each tooth bud consists of an enamel organ which has several layers, both epithelial and mesenchymal
  • Crown of tooth is formed first, with root formation completed afterwards
  • A specialized form of epithelium (Hertwig epithelial root sheath) directs root formation, and once complete, it degenerates, leaving epithelial rests of Malassez
  • These rests are not isolated but form vague net-like structures around root of tooth within periodontal ligament (fibrous tissue connection between tooth root and bone of jaw)
  • Residual dental lamina, from bud-like invagination process of tooth formation, is source of epithelial rests of Serres, located primarily in gingival soft tissues
  • A third source of epithelium is reduced enamel epithelium, which arises from enamel organ (www.Embryology.ch., chapter 19, J Endod 2007;33:908)
Microscopic (histologic) description
  • Odontogenic cysts are variable, depends on cyst type
  • Rests of Malassez (from Hertwig epithelial root sheath): small spherules of 6 - 8 epithelial cells with high nuclear to cytoplasmic ratio; little or no reverse polarity of cells
Virtual slides

Images hosted on other servers:

Developing tooth / dental lamina

Positive stains
Negative stains
Electron microscopy description
Rests of Malassez:
  • High nuclear - cytoplasmic ratio of epithelial cells
  • Nucleus with condensed heterochromatin and 1 - 2 poorly developed nucleoli; nuclear contour is irregular with occasional deep infoldings
  • Tonofilaments and relatively abundant mitochondria in most cells
  • Varying amounts of glycogen granules and lipid droplets in cytoplasm
  • Rough endoplasmic reticulum is poorly developed and Golgi complex is close to nucleus (Arch Oral Biol 1989;34:179)
Odontogenic cysts:
  • Variable, depends on cyst type
Videos

Images hosted on other servers:

Eruption of teeth

Tooth development

Tooth development

Differential diagnosis
  • In general, 'epithelium' within an intraosseous, gnathic location may have a broad differential diagnosis depending on the amount of epithelium present for evaluation, type of epithelium, anatomic location of lesion in gnathic bones, radiographic appearance, clinical scenario and patient demographics

  • Odontogenic, inflammatory cysts: apical cyst, buccal bifurcation cyst, lateral cyst, residual cyst
  • Odontogenic, developmental cysts: botryoid odontogenic cyst, dentigerous cyst, glandular odontogenic cyst, lateral periodontal cyst, orthokeratinized odontogenic cyst, primordial cyst
  • Odontogenic, neoplastic cysts: calcifying odontogenic cyst, carcinoma ex-cyst, keratocystic odontogenic tumor (often referred to as odontogenic keratocyst), unicystic ameloblastoma
  • Non-odontogenic cysts: dermoid cyst, epidermoid cyst, median palatal cyst, nasopalatine duct cyst, surgical ciliated cyst
  • Benign odontogenic hamartomas and odontogenic tumors that may contain epithelium:
  • Primary intraosseous carcinoma:
  • Malignant epithelial lesions: metastatic or invading by extension into jaw bones: (Oral Oncol 2008;44:743)
    • Basal cell carcinoma, by extension / perineural invasion from overlying skin, not metastasis
    • Breast
    • Lung
    • Prostate
    • Squamous cell carcinoma
    • Squamous cell carcinoma, by extension from oral cavity
  • Odontogenic rests or benign regional anatomy:
    • Inflamed gingival crevicular epithelium in periodontal disease; may be fragmented and appear intraosseous
    • Normal dental follicle epithelium around unerupted teeth
    • Rests of Malassez
Additional references