An odontogenic keratocyst (OKC) is a type of developmental cyst involving the mandible or maxilla.
Odontogenic keratocysts typically present in younger patients (2nd - 3rd decades), are often multiple, and may be seen in either the body or ramus of the mandible (approximately 70% of all OKCs), or maxilla. There may be male predilection.
OKCs originate from epithelial cell rests (stratified squamous keratinizing epithelium) found along the dental lamina and periodontal margin of the alveolus of the mandible.
- basal cell naevus syndrome (or Gorlin-Goltz syndrome) : strong association.
- Marfan syndrome
- Noonan syndrome
Plain film (OPG)
Typically seen as a solitary, lucent, unilocular lesion with smooth, corticated borders 5. When in the mandible, they typically grow along the length of the bone. In the maxilla, OKCs may expand into the maxillary sinus (as in Case 2).
They are often associated with an impacted tooth, mimicking a dentigerous cyst. OKCs may occasionally appear septated, making the distinction from ameloblastoma difficult. The presence of multiple OKCs is associated with Gorlin-Goltz syndrome.
An OKC will typically demonstrate 3
- T1 : low signal
- T2 : high signal
Treatment and prognosis
They are locally aggressive. Treatment is often with enucleation / excision + / -aggressive curettage. They however can have a very high recurrence rate (30 - 60%)
- dentigerous cyst if pericoronal
- calcifying odontogenic cyst (Gorlin cyst) and other odontogenic cysts and tumours
- 1. Dunfee BL, Sakai O, Pistey R et-al. Radiologic and pathologic characteristics of benign and malignant lesions of the mandible. Radiographics. 26 (6): 1751-68. doi:10.1148/rg.266055189 - Pubmed citation
- 2. Gorlin RJ, Cohen MM, Hennekam RC. Syndromes of the head and neck. Oxford University Press, USA. (2001) ISBN:0195118618. Read it at Google Books - Find it at Amazon
- 3. Mafee MF, Valvassori GE, Becker M. Imaging of the head and neck. George Thieme Verlag. (2004) ISBN:1588900096. Read it at Google Books - Find it at Amazon
- 4. Yonetsu K, Bianchi JG, Troulis MJ et-al. Unusual CT appearance in an odontogenic keratocyst of the mandible: case report. AJNR Am J Neuroradiol. 22 (10): 1887-9. AJNR Am J Neuroradiol (full text) - Pubmed citation
- 5. Scholl RJ, Kellett HM, Neumann DP et-al. Cysts and cystic lesions of the mandible: clinical and radiologic-histopathologic review. Radiographics. 19 (5): 1107-24. Radiographics (full text) - Pubmed citation
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|Odontogenic keratocyst (OKC)||✗|
|Keratocystic odentogenic tumour||✓|
|Odontogenic keratocysts (OKC)'s||✗|
|Keratocystic odentogenic tumours||✗|
|Keratocystic odentogenic tumor||✗|
|Keratocystic odentogenic tumors||✗|