Biomimetic microenvironments for regenerative endodontics

Abstract

Regenerative endodontics has been proposed to replace damaged and underdeveloped tooth structures with normal pulp-dentin tissue by providing a natural extracellular matrix (ECM) mimicking environment; stem cells, signaling molecules, and scaffolds. In addition, clinical success of the regenerative endodontic treatments can be evidenced by absence of signs and symptoms; no bony pathology, a disinfected pulp, and the maturation of root dentin in length and thickness. In spite of the various approaches of regenerative endodontics, there are several major challenges that remain to be improved: a) the endodontic root canal is a strong harbor of the endodontic bacterial biofilm and the fundamental etiologic factors of recurrent endodontic diseases, (b) tooth discolorations are caused by antibiotics and filling materials, (c) cervical root fractures are caused by endodontic medicaments, (d) pulp tissue is not vascularized nor innervated, and (e) the dentin matrix is not developed with adequate root thickness and length. Generally, current clinical protocols and recent studies have shown a limited success of the pulp-dentin tissue regeneration. Throughout the various approaches, the construction of biomimetic microenvironments of pulp-dentin tissue is a key concept of the tissue engineering based regenerative endodontics. The biomimetic microenvironments are composed of a synthetic nano-scaled polymeric fiber structure that mimics native pulp ECM and functions as a scaffold of the pulp-dentin tissue complex. They will provide a framework of the pulp ECM, can deliver selective bioactive molecules, and may recruit pluripotent stem cells from the vicinity of the pulp apex. The polymeric nanofibers are produced by methods of self-assembly, electrospinning, and phase separation. In order to be applied to biomedical use, the polymeric nanofibers require biocompatibility, stability, and biodegradability. Therefore, this review focuses on the development and application of the biomimetic microenvironments of pulp-dentin tissue among the current regenerative endodontics.

Biomimetic Conditioning of Human Dentin Using Citric Acid

“…Chemically released growth factors are important in regenerative procedures (6,7). Transforming growth factor beta 1 (TGF-b1) induces cell proliferation, differentiation, and chemotaxis in different cell types.…”

Pulp–Dentin Tissue Healing Response: A Discussion of Current Biomedical Approaches

“…Among the newly developed synthetic polymer, a NO releasing biomimetic nanomatrix gel was evaluated as a nature mimicking novel PA based scaffold [145]. This self-assembled PA gel mimics the ECM and provides a controlled release of NO, showing the therapeutic roles of disinfection, revascularization, and regeneration [146] (Figure 2). The antibacterial aspect of NO is critical for dental pulp regeneration to ensure a sterile pulp-dentin tissue environment and recruit healthy cell growth including DPSCs and neurovascular cells to promote revascularization.…”

Platelet-rich plasma for regeneration of neural feedback pathways around dental implants: a concise review and outlook on future possibilities

“…Appropriate animal models, chosen according to various objectives, are likely to produce convincing and clinically relevant results. Thus, it is important to use an animal model with characteristics comparable to those of the ultimate treatment cohort, 95, 96 including common aspects of anatomy, physiology, histology, pathology and even gene expression. For research in implant dentistry, the animal model should have relatively large teeth and extraction sockets that are convenient for surgery, and it should be possible to take radiographs at the surgical site during follow-up.…”