Odontoblast primary cilia: facts and hypotheses.

Odontoblasts, the cells responsible for the dentine formation, are organized as a single layer of highly polarized and differentiated post-mitotic cells along the interface between the dental pulp and the mineralized tubules. They lay down the physiological secondary dentine throughout the life of the teeth. Odontoblasts play a central role in the transportation of calcium to the dentine and they possibly mediate early stages of sensory processing in teeth. A primary cilium, 9+0 configuration, have been regularly identified in a supra nuclear location. Calbindin D28k has been detected at the base of the cilium membrane. The cilium structure was positive with detyrosinated alpha tubulin antibodies in vivo and in cultured human odontoblasts. Transcripts of tektin, a protein involved in ciliogenesis, were expressed in vitro. The putative role of the primary cilium constituting a critical link between external teeth stimuli and odontoblast responses is extensively discussed.