Regenerative endodontic procedures are generally accepted by experts part 1

 

Regenerative endodontic procedures (REPs) are biologic-based treatments for pulp necrosis in developing permanent teeth. The main goals of REPs are to regenerate the pulp-dentin complex, prolong the life of the tooth, and regain normal function. Through case reports, case series, cohort studies, and randomized controlled studies, scientific evidence has shown that REPs are effective at promoting root development. However, due to the empirical nature of the original protocols and the quick development of regenerative endodontics as a field of study, there are variations in clinical protocols for REPs. Dental professionals may become confused by the heterogeneity of protocols, so REP guidelines and considerations should be explained.  In order to improve the clinical management of REPs in accordance with the advancement of basic researches and clinical studies, it is suggested that REPs may become a more consistently evidence-based option in dental treatment. This expert consensus mainly discusses the biological foundation, the available clinical protocols and current status of REPs in treating immature teeth with pulp necrosis, as well as the main complications of this treatment.

 

A common condition treated in dental clinics is pulpal and periradicular pathosis, which can be brought on by caries, trauma, or dental abnormalities. The traditional method of treating endodontic diseases in fully developed permanent teeth is root canal therapy (RCT), which has excellent clinical results. For immature permanent teeth with pulp necrosis, the conventional method of treatment is apexification.  Endodontic therapy aims to reduce pulp and periapical inflammation/infection while protecting teeth. However, because the pulp and some dentin tissues are removed during these treatments, the dentinal strength, immunological responses, and proprioceptive functions are compromised, increasing the risk of reinfection and tooth fracture. Modern endodontics aims to reconstruct vital pulp and reestablish the biological function of teeth.

 

Nygaard-stby first proposed the idea of pulp tissue regeneration in the 1960s, setting the stage for regenerative endodontics. Revascularization was successfully used by Iwaya et al.6 in 2001 to induce root development and restore pulpal sensitivity in a young permanent tooth with apical periodontitis. As support for the clinical use of regenerative endodontics, Banchs and Trope7 reported a case in 2004 with a modified protocol of revascularization, specifically creating a blood clot in the canals after disinfection as a matrix for new tissue growth and a bacterial-tight coronal seal to prevent bacterial invasion into the pulp space. Regenerative endodontic procedures (REPs), cell homing, and stem cell transplantation are the main strategies used today. While only REPs have seen widespread use in clinical practice, stem cell transplantation has been reported to successfully regenerate pulp tissue in a clinical setting. The goal of REPs, a biologically based approach that incorporates the idea of tissue engineering to replace damaged structures like dentin and cells of the pulp-dentin complex, is to continue root development and strengthen dentinal tissues to prevent potential root fracture. REPs also aims to heal apical lesions and eliminate signs and symptoms. The ultimate objective is to restore immune competency, a functional pulp-dentin complex, and typical nociception.

 

Since the first case reported in 2001, there has been an increase in studies using REPs to treat young permanent teeth with apical periodontitis. To date, more than 600 articles are found at PubMed when searching with the keywords “revascularization”, “revitalization” and “regenerative endodontics”. Article types include basic researches, case reports, case series, retrospective studies, prospective clinical trials, reviews and guidelines, the majority of which are case reports, basic researches and reviews. At present, two guidelines on REPs are available for dental practitioners. The American Association of Endodontists (AAE) published the clinical guideline on REPs in 2013, and updated the versions in 2016, 2018 and 2021. The European Society of Endodontology (ESE) position statement published in 2016 provides similar procedure details but a few differences in medicament choice, blood clot formation, placement of capping materials and success criteria of REPs.

Regenerative endodontic procedures (REPs), stem cell transplantation, and cell homing are the main strategies used today. Only REPs have seen widespread use in clinical practice, despite reports that stem cell transplantation can successfully regenerate pulp tissue. REPs is a biologically based approach that incorporates the idea of tissue engineering to replace damaged structures, including dentin and cells of the pulp-dentin complex,8 with the goal of promoting continued root development and stronger dentinal tissues to prevent potential root fracture in addition to apical lesion healing and symptom resolution. The end result is the regeneration of a healthy pulp-dentin complex, immune competence, and normal nociception.

 

Terminologies in the REPs field have been evolving, including pulp revascularization, revitalization, regenerative endodontic therapy and regenerative endodontic procedures. Among them, the term “pulp revascularization” has been most commonly used in the publications. However, it should be emphasized that the regenerative procedures aim at not only reestablishment of vascularity in pulp tissues but also functional regeneration of pulp-dentin complex. From this perspective, it is inaccurate to simply name the regenerative endodontic modality as “pulp revascularization”. In 2007, Murray et al.  introduced the term of regenerative endodontic procedures to recapitulate the tissue engineering essence of pulp regeneration. The AAE adopted this terminology in its clinical guideline and also included it in the Glossary of Endodontic Terms of 2020, while ESE referred to this biologically based approach as revitalization. In this expert consensus, “regenerative endodontic procedures” is used to describe this strategy.

 

 See also youtube video about MTA APEXIFICATION case 1 apexification steps