Infection and Pulp Regeneration

Abstract

The regeneration of the pulp-dentin complex has been a great challenge to both scientists and clinicians. Previous work has shown that the presence of prior infection may influence the characteristics of tissues formed in the root canal space after regenerative endodontic treatment. The formation of ectopic tissues such as periodontal ligament, bone, and cementum has been observed in the root canal space of immature necrotic teeth with apical periodontitis, while the regeneration of dentin and pulp has been identified in previously non-infected teeth. The current regenerative endodontic therapy utilizes disinfection protocols, which heavily rely on chemical irrigation using conventional disinfectants. From a microbiological point of view, the current protocols may not allow a sufficiently clean root canal microenvironment, which is critical for dentin and pulp regeneration. In this article, the significance of root canal disinfection in regenerating the pulp-dentin complex, the limitations of the current regenerative endodontic disinfection protocols, and advanced disinfection techniques designed to reduce the microorganisms and biofilms in chronic infection are discussed.

Clinical and radiographic evaluation of Biodentine and Mineral Trioxide Aggregate in revascularization of non‐vital immature permanent anterior teeth (randomized clinical study)

“…This finding was in agreement with Kim who reported that cases seen after a long post‐traumatic period showed more complications than those presented within a short period. This could be explained that although it was difficult or impossible to determine the presence of viable cells clinically or to assess the ability of these cells to survive and differentiate, the duration of the infection appears to be an indicator of that potential …”

“…One case in the MTA group was identified as a clinical failure due to the presence of pain on biting and pain on percussion at 12‐month follow‐up. As postulated by several reports, the failure might be due to the increased bacterial growth in the dentinal tubules, accessory canals or the biofilm on the canal wall, and thus, the canal became re‐infected and caused tissue destruction.…”

Regenerative endodontics: a comprehensive review

“…Journal of Endodontics 43, 2034-40. Zhujiang A, Kim SG (2016) Regenerative endodontic treatment of an immature necrotic molar with arrested root development using recombinant human platelet-derived growth factor: a case report. Journal of Endodontics 42, 72-5.…”

“…However, if infection is not under control, not only regeneration but also repair will not occur (Myers & Fountain 1974). The presence of prior infection could negatively affect the process of pulp tissue regeneration by damaging tissue forming cells as well as stem cells in the periapical tissues (Kim 2016). This is supported by the histological findings from animal studies and human case reports that tissues formed in the root canal space in the previously infected root canals were not the pulp-dentine complex but of periodontal origin such as bone, cementum and periodontal ligament (Wang et al 2010, Becerra et al 2014, Lei et al 2015, Saoud et al 2015.…”

“…Mechanical debridement is not recommended in RET for immature permanent teeth with a necrotic pulp because removal of root canal dentine could weaken the already thin and fragile root and render the root more prone to fracture. However, the effectiveness of disinfection protocol in RET was questioned , Nagata et al 2014, Kim 2016, Vishwanat et al 2017). Similar to nonsurgical and surgical endodontic therapy, control of root canal infection is the key to the success of regenerative endodontic therapy (Fouad 2017).…”