Journal of the Japanese Association of Regenerative Dentistry
J Jpn Assoc Regenerative Dent Vol.7(1) pp.25-33
ISSN 1348-9615


Histological Investigation of the Neurotization of Human Dental Pulp by Indirect Pulp Capping using MTA

Atsushi OOKUBO, Masaaki INOUE, Tsunenori MATSUNAGA, Masaki TSUJIMOTO
HIU Dental Clinical Institute

Objectives: The white Mineral Trioxide Aggregate / ProROOT MTA® is authorized in Japan from October, 2006, and it is sold. There is necessity evaluating ProROOT MTA®. For reports of the inflammatory reaction of the pulp tissue which the possibility that some problem of ultra-microelement, arsenic trioxide and the strong alkali pH included in MTA inhibit mineralized contribution.
Materials and method: We got patient compliance and used 4 cases caries-free human permanent third molars and premolars scheduled for extraction for orthodontic reasons from 19 and 22 years old woman, in which mechanical pulp exposures, hemostasis in 2%NaClO, dried with disinfection pledget and capped with ProROOT MTA®. We reviewed human pulp tissue regeneration of 2 weeks and 4 weeks by H-E staining for histological regeneration and S100 positive staining for dental pulp neurotization.
Results and discussion: The histological transendothelial time comparison is not possible so that a condition varies with human. As for the results, the dentin-bridge formation and the regeneration of the dental pulp nervous system are not seen in pulp tissue under ProROOT MTA® which did pulp capping almost in 2 weeks statueDHowever, the hyperaemia and the tissue degeneration were not recognized around ProROOT MTA® particle. We showed the osteoid or cement-like dentin-bridge formed by about 200 µm width in 4 weeks statue. Normal pulp tissue and odontoblast are recovering the boundary surface right under the mineralized layer. The Schwann cells were not observed in the statue at all for 2 weeks statue, but there was much statue which regenerated right under mineralization lamina, and the Schwann cells were observed in statue for 4 weeks statue. Hyperaemia and tissue degeneration were not found in human pulp tissue around the MTA particle which did extravasation for 2 and 4 weeks statue of both specimensDWe think ultramicro arsenic trioxide and alkali pH does not have the influence with the human pulp tissue and biological regulation is considered to be it.
Also, there seemed to be association in dental pulp neurotization and dentin mineralization from these specimens.

Keyword: ProROOT MTA®, pulp capping, S100 positive staining, dental pulp neurotization, dentin-bridge formation