Regenerative approaches for endodontics

Abstract

Complete regeneration of dental pulp tissue is the main focus of procedures in regenerative endodontics. The two major strategies currently under exploration are tissue engineering-based pulp regeneration and pulp revascularization. The pulp regeneration strategies based on tissue engineering rely on three key elements: autologous/exogenous dental stem cells, bioactive scaffolds, and signaling molecules. In these approaches, either the exogenous stem cells are in vitro expanded and transplanted or signaling molecules and/or bioactive scaffolds are used as cues to recruit endogenous stem/progenitor cells into the root canal system. Through either of approaches, the differentiation of stem cells into odontoblast-like cells is expected in order to facilitate the pulp-like tissue formation. Rapid vascularization is of paramount importance in the survival and integration of engineered pulp tissue. Incorporation of pre-fabricated microvascular networks into the engineered tissue constructs could promote immediate connection with the host circulation following implantation. Additionally, endothelial cells derived from dental stem cells could be used in vasculature engineering that will greatly contribute to dental pulp regeneration. In parallel to the tissue engineering approaches, regenerative endodontic procedures (REPs), which focus on dental pulp revascularization, have become a part of routine endodontic clinical practice. REPs mainly include three steps: disinfection, evoking blood into the root canal, and achievement of a coronal seal. Several clinical trials have reported favorable outcomes with this technique in relation to necrotic immature teeth. However, histological studies have shown that tissues formed in the root canal space are cementum, periodontium, and bone-like tissues rather than pulp–dentin complex. Further studies, therefore, are required to optimize the conditions that could promote natural dentin/pulp-complex-like tissue regeneration. Copyright © 2022 Elsevier Ltd.