The ultrastructure of the rat incisor odontoblast in organ culture.

Extracted incisors were dissected free of adherent soft tissue, split by a longitudinal incision lingually and the pulp sac carefully removed. The predentine-dentine pieces with attached odontoblasts were incubated for up to 24 h in culture medium in 5 per cent CO2, humid air at 37 degrees C. The cultures were recovered and processed for light microscopy and transmission electron microscopy. Examination of the explants showed a homogeneous layer of odontoblasts attached to the dentinal surface. The odontoblasts had a normal structure and nuclear polarity similar to that seen in vivo. There were no apparent degenerative changes.