Regenerative endodontics for immature permanent teeth after trauma

Introduction and background

The management of immature permanent teeth with pulp necrosis, often resulting from traumatic injuries or deep carious lesions, represents a major clinical challenge in endodontics. These teeth typically exhibit open apices, thin dentinal walls, and incomplete root development, making them structurally compromised and more susceptible to fracture and long-term failure if inadequately treated [1]. The primary therapeutic goal is not only the elimination of infection but also the facilitation of root maturation to improve the tooth’s long-term structural integrity and functional retention.

Comparison of Revascularization and Apexification Using Mineral Trioxide Aggregate in Young Human Immature Nonvital Teeth: A Systematic Review and Meta-Analysis. Copyright © 2025, Pendse et al. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).

Teeth need root canal retreatment

Recently, regenerative endodontic procedures (REPs) have been generally accepted as a treatment option for necrotic immature teeth. The steps of REPs contain intracanal medicaments, induction of bleeding, and placement of Mineral trioxide aggregate (MTA). If REPs fail or the teeth are traumatized, MTA barrier may need to be removed and RCT could be performed.64 In some teeth, mineralized tissues deposited in the canals and induced PCO after REPs in long-term inspection.65 Analogous to the post removal, MTA removal in the teeth previously treated by REPs may also result in excessive dentinal loss or iatrogenic deviation. An ex vivo study employed SGE for MTA removal and suggest it as a useful way,66 but no clinical report or study has been announced. Moreover, in some cases, the treatment of PCO leads to iatrogenic deviation or perforation in root canals.67 Well-designed 3D guide seemed to be feasible for returning to the original canal and reaching patency during retreatment in some cases,68–71 but it should be clearly evaluated whether the canal relocation is worthy since DGT may furtherly weaken the tooth structure.

Expert consensus on digital guided therapy for endodontic diseases. © The Author(s) 2023. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).

Results

TABLE 6 — Managing pulp pathoses in primary & permanent teeth with traumatic injuries. | Statement | Type of statement | Strength of evidence (percent agreement) 34. | Appropriate follow up of traumatic injuries is important due to the risk of late complications such as discoloration, pulp necrosis, arrest of root formation, apical periodontitis, external inflammatory root resorption, external replacement (ankylosis‐related) resorption, external invasive resorption, and internal resorption. The incidence and management of these complications differ between primary and permanent teeth. | Consensus‐based Recommendation | Conditional (> 70%) 35. | Traumatized immature permanent teeth with pulp necrosis can be managed either by RET or by apical plug using CSC barrier. Both methods have demonstrated comparable clinical, radiographic, and overall success and survival rates. However, RET may be preferred for necrotic teeth in very early stages of root development and for teeth with developmental dental anomalies. | Consensus‐based Recommendation | Conditional (> 70%) 36. | External inflammatory root resorption can be arrested by careful removal of causative factors by endodontic debridement, irrigation, and use of intracanal medicament (Calcium Hydroxide, Triple Antibiotic Paste, Double Antibiotic Paste). External replacement resorption is progressive in nature and cannot be stopped or reversed. In permanent teeth, decoronation or root submergence or autotransplantation and extraction are acceptable treatments in suitable patients. | Consensus‐based Recommendation | Conditional (> 70%)

Consensus‐Based Recommendations on Pulp Therapies in Primary and Permanent Teeth: IAPD Porto Forum. © 2026 The Author(s). International Journal of Paediatric Dentistry published by BSPD, IAPD and John Wiley & Sons Ltd. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).

Discussion

This is particularly important in the immediate post‐trauma period when current diagnostic tools may be unreliable. Studies are needed to identify early indicators of pulp necrosis and better understand healing patterns in different types of traumatic injuries. Age‐related differences in healing responses require further investigation, especially in determining the optimal timing of intervention after trauma. Research into regenerative approaches for traumatized immature permanent teeth is particularly important, as these cases present unique challenges and opportunities for promoting continued root development [23]. Several research priorities span across all areas of pulp therapy. The development of standardized outcome measures and uniform reporting criteria for clinical studies is essential for advancing the field. The need for a well‐sealed restoration following vital pulp therapy is universally recognized; however, there is a critical need to deepen our understanding of the molecular and cellular mechanisms underlying pulp‐dentin complex responses to injury and treatment.

Consensus‐Based Recommendations on Pulp Therapies in Primary and Permanent Teeth: IAPD Porto Forum. © 2026 The Author(s). International Journal of Paediatric Dentistry published by BSPD, IAPD and John Wiley & Sons Ltd. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).

Introduction and background

In contrast, RET, also known as regenerative endodontic therapy (RET), offers the potential for true tissue regeneration within the canal. It leverages the presence of stem cells from the apical papilla, signaling molecules, and a suitable scaffold to regenerate pulp-like tissue that can support continued root growth and apical closure [3]. The technique has shown promising outcomes, including increased root length and dentinal wall thickness, which translate into improved long-term prognosis. MTA is commonly employed as a coronal barrier due to its biocompatibility and sealing properties.

Comparison of Revascularization and Apexification Using Mineral Trioxide Aggregate in Young Human Immature Nonvital Teeth: A Systematic Review and Meta-Analysis. Copyright © 2025, Pendse et al. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).

Introduction

The treatment of pulp necrosis in teeth with open apices poses significant challenges due to factors like wide root canals, thin dentinal walls, and shortened roots [1]. Some authors have proposed regenerative endodontic procedures (REP) as an alternative for the treatment of mature teeth with open apex [2, 3, 4]. The aim of REP is to promote root development, increase root length, thicken the dentine walls, and achieve apical closure [5]. It is believed that REP may reduce the risk of tooth fracture, increasing its longevity [2, 3]. The success rate of REP ranges from 83% to 93% [6]. Several factors are essential for the success of REP, including control of endodontic infection, blood clot formation, stem cells, and activators [7]. However, the composition and concentration of the clot are unpredictable, and this uncertainty increases with age [2, 3, 4, 5].

Regenerative Endodontic Procedure of a Mature Anterior Tooth With Open Apex and Chronic Apical Abscess: A Case Report With 4‐Years Follow‐Up. © 2025 The Author(s). Clinical Case Reports published by John Wiley & Sons Ltd. Creative Commons Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/).