Update on the adaptive immune responses of the dental pulp.

Recent advances in immunology have disclosed the enormous complexity of the immune regulatory system. The dental pulp is equipped to mount adaptive immune responses to caries, which include at least antigen-presenting cells, lymphocytes, mast cells and their cytokines, and chemokines. The purpose of this review is to summarize our current understanding of the roles of these cellular and molecular components in the irreversibly inflamed pulp. The immunopathology of abscess formation and the mechanisms for painless pulpitis are also discussed.