Autosomal dominant polycystic kidney disease (ADPKD), an inherited disease, 
leads to cyst formation in the kidneys. In this condition, the kidneys are 
grossly enlarged with multiple cysts that result in kidney failure in a majority 
of individuals. This condition is also associated with cysts in other organs. 
Recent research has focused on defects in signaling mediated by the primary 
cilia as the causative factor in ADPKD. Primary cilia are also present in 
odontogenic epithelium. Dentigerous cyst also is a developmental cyst whose 
pathogenesis is controversial. Recent studies have shown that loss of Ptch and 
Shh signaling pathways are involved in the cystogenesis of dentigerous cyst. The 
Shh signaling pathway is active in the primary cilia. A scanning electron 
microscopic study of a dentigerous cyst wall in an ADPKD patient showed 
structures similar to primary cilia. Based on the presentation of a dentigerous 
cyst in an autosomal dominant polycystic kidney patient and the demonstration of 
primary cilia like structures on the cyst wall by using a scanning electron 
microscope, a new hypothesis for the pathogenesis of dentigerous cyst is 
proposed.