Thomas H F, Payne R C
J Dent Res. 1983 May;62(5):532-6. doi: 10.1177/00220345830620050201.
Different regions of crown dentin from erupted human premolars were examined ultrastructurally to determine the contents of the dentinal tubules. Odontoblast processes were limited to inner dentin, and nerve fibers were not observed in any tubules examined.