WHO 2017 Odontogenic cysts Flashcards
Classifications of cysts
Developmental - dentigerous - okc - lat periodontal cyst - gingival cyst - glandular odontogenic cyst - calcifying odontogenic cyst - orthokeratinized odontogenic cyst Inflammatory - radicular - collateral inflammatory cyst
Why is okc taken out of tumor classficiation
- PTCH gene mutation can also occur in non-neoplasms
2. The shrinkage of lesion upon marsupialization does not indicate a neoplastic process.
Histopath characteristics of OKC
Thin stratified squamous epithelium 5-6 layers
Without rete ridges
Palisaded and hyperchromatic basal cells
Wht is COC
A developmental cyst
A cystic form of DGOC
Mixed radiolucent radiopaque lesion - could be unilocular or multilocular with irregular calcifications
Treated by E&C
What is OOC orthokeratinized odontogenic cyst
Developmental cyst
Previously falls under KCOT (orthokeratinized type)
But is being pulled out as a single entity becos has very different characters
- not assoc with syndromes
- low to no recurrent rate
- do not show aggressive behaviour
Histopath:
Stratified squamous epithelium 5-6layers without retw ridges
NO palisaded basal cells
What is diff dx of glandular odontogenic cyst
Central mucoepidermoid carcinoma
However- GOC has no mutations in MAML2 gene
Clincal presentation ofGOC
Unilocular or multilocular radiolucency
Histopath characterized by stratified squamous epithelium that exhibits surface columnar cells with cilia.
Numerous microcysts containing mucinous material are present.
Recurrence rate of OKC for various treatments
10-15% when cyst enucleation + carnoys
whats the penetration of Carnoys in cyst wall, mucosa, nerve and bone when applied for 5mins
Nerve - 0.15mm
Mucosa - 0.5mm
Cyst wall - 0.75mm
Bone - 1.5mm
Reasons for recurrence of OKC
Satellite cyst
Daughter cyst
Thin friable epithelium deemed incomplete removal
Remnants of dental lamina
