Endodontic regeneration: hard shell, soft core

Regenerative Medicine, 2009

Dental pulp tissue is vulnerable to infection. Entire pulp amputation followed by pulp-space disinfection and filling with an artificial rubber-like material is employed to treat the infection – commonly known as root-canal therapy. Regeneration of pulp tissue has been difficult as the tissue is encased in dentin without collateral blood supply except from the root apical end. However, with the advent of the concept of modern tissue engineering and the discovery of dental stem cells, regeneration of pulp and dentin has been tested. This article will review the early attempts to regenerate pulp tissue and the current endeavor of pulp and dentin tissue engineering, and regeneration. The prospective outcome of the current advancement in this line of research will be discussed.

Journal of endodontics, 2016

The development of regenerative endodontic therapies offers exciting opportunities for future improvements in treatment outcomes. Advances in our understanding of regenerative events at the molecular and cellular levels are helping to underpin development of these therapies, although the various strategies differ in the translational challenges they pose. The identification of a variety of bioactive molecules, including growth factors, cytokines, chemokines, and matrix molecules, sequestered within dentin and dental pulp provides the opportunity to present key signaling molecules promoting reparative and regenerative events after injury. The protection of the biological activity of these molecules by mineral in dentin before their release allows a continuing supply of these molecules, while avoiding the short half-life and the non-human origin of exogenous molecules. The ready release of these bioactive molecules by the various tissue preparation agents, medicaments, and materials c...

Mansoura Journal of Dentistry, 2021

Stem Cells International, 2016

Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage o...

Journal of Tissue Engineering and Regenerative Medicine, 2018

More than two thirds of the global population suffers from tooth decay, which results in cavities with various levels of lesion severity. Clinical interventions to treat tooth decay range from simple coronal fillings to invasive root canal treatment. Pulp capping is the only available clinical option to maintain the pulp vitality in deep lesions, but irreversible pulp inflammation and reinfection are frequent outcomes for this treatment. When affected pulp involvement is beyond repair, the dentist has to perform endodontic therapy leaving the tooth non-vital and brittle. Ongoing research strategies have failed to overcome the limitations of existing pulp capping materials so that healthy and progressive regeneration of the injured tissues is attained. Preserving pulp vitality is crucial for tooth homeostasis and durability, and thus, there is a critical need for clinical interventions that enable regeneration of the dentin-pulp complex to rescue millions of teeth annually. The identification and development of appropriate biomaterials for dentin-pulp scaffolds are necessary to optimize clinical approaches to regenerate these hybrid dental tissues. Likewise, a deep understanding of the interactions between the micro-environment, growth factors, and progenitor cells will provide design basis for the most fitting scaffolds for this purpose. In this review, we first introduce the long-lasting clinical dental problem of rescuing diseased tooth vitality, the limitations of current clinical therapies and interventions to restore the damaged tissues, and the need for new strategies to fully revitalize the tooth. Then, we comprehensively report on the characteristics of the main materials of naturally-derived and synthetically-engineered polymers, ceramics, and composite scaffolds as well as their use in dentin-pulp complex regeneration strategies. Finally, we present a series of innovative smart polymeric biomaterials with potential to overcome dentin-pulp complex regeneration challenges.

Dental pulp therapy of teeth degraded by caries, dental wear lesions (abrasion, attrition, erosion) or trauma is currently limited to conventional restorations such as pulp capping or root canal therapy. Therefore, dental research focusing on strategies for vital pulp therapy might open a promising alternative to the removal of the whole pulp by maintaining the function of the tooth. The implementation of a medical device in dental and oral tissue engineering is based on potential cell sources and biocompatible materials applied as direct pulp capping agents, which can also serve as a carrier of signalling molecules. In addition to nerves and blood vessels, the pulp contains highly proliferative stem/progenitor cells possessing a self-renewal and differentiation capability. The latter have the ability to regenerate degraded dentin in vivo when compromised dentin is located close to the pulp. Hence, the design of a suitable biomaterial is focused on both the healing potential through...

Clinical Oral Investigations, 2008

Considerable focus on the biocompatibility of dental materials over the last three decades has provided a platform for a wealth of studies on the cellular and molecular responses of the cells of the pulp to injury, both from the disease process and from subsequent restorative intervention. These studies have been fundamental to understanding not only how we can achieve a biocompatible response during restoration of dental disease but also how we can exploit the pulpal cellular responses to achieve wound healing and tissue regeneration in the dentine-pulp complex. This article examines the responses of the pulp to injury and the events leading to tissue regeneration. As new biologically based regenerative therapies emerge for the dental tissues, it is important that these develop in partnership with more traditional approaches using dental materials.

Iranian Endodontic Journal, 2014

Regenerative endodontic procedure is introduced as a biologically based treatment for immature teeth with pulp necrosis. Successful clinical and radiographic outcomes following regenerative procedures have been reported in landmark case reports. Retrospective studies have shown that this conservative treatment allows for continued root development and increases success and survival rate of the treated teeth compared to other treatment options. Although the goal of treatment is regeneration of a functional pulp tissue, histological analyses show a different outcome. Developing predictable protocols would require the use of key elements for tissue engineering: stem cells, bioactive scaffolds, and growth factors. In this study we will review the evidence based steps and outcomes of regenerative endodontics.

Journal of Endodontics, 2020

Stem cell-mediated regenerative endodontics has reached the human clinical trial phase; however, many issues still exist that prevent such technology to be a widely used clinical practice. These issues are not straightforward and are complicated. They should be because pulp regeneration is dealing with a small dead-end space. In addition, when regeneration is needed, the space is often heavily infected. The true standard of pulp regeneration should be everything except generation of some fibrous connective tissue and amorphous mineral deposit. As of now, we are still far short of reaching the standard of complete vascularized and innervated pulp regeneration with newly formed tubular dentin in all types of teeth. Thus, we need to go back to the bench and use established animal models or create new animal models to tackle those issues. This article will address several key issues including the possibility of pulp regeneration in small canals of molar teeth by enhancing the neovascularization, and whether the organized tubular dentin can be generated on the canal walls. Data from our semi-orthotopic tooth fragment mouse model have shown that complete pulp regeneration using dental pulp stem cells (DPSCs) in small canal has been inconsistent because of limited blood supply. This inconsistency is similar in our orthotopic miniature swine model, although in some cases vascularized pulp-like tissue can be formed throughout the canal space after DPSC transplantation. Furthermore, no tubular dentin was observed in the orthotopic pulp regeneration, despite the fact that DPSCs have the capacity to generate some tubular dentin-like structure in the hydroxyapatite/tricalcium phosphate-mediated ectopic pulp/dentin formation model in mice. Potential strategies to be tested to address these regeneration issues are discussed herein.

International journal of health sciences

Nanotechnology has completely revolutionized the field of Dentistry with enormous applications and opened up ample research opportunities in the field. Most research activities in Endodontics are performed in pursuit of regeneration of pulpo-dentinal complex. As in other fields, nanotechnology has ameliorated regenerative Endodontics and has brought about considerable promise to the field. Application of nanotechnology could even increase thesuccess rate of regeneration owing to biomimetic modifications in stem cells and scaffolds, which may soon be translated to clinical practice. This review highlights the important research activities in regeneration of dental pulp in collaboration with nanotechnology.