Redefining regeneration: proposal of a radiographic outcome-based framework for evaluating regenerative endodontic procedures in immature necrotic teeth

Ruchi Singhal; Akshita Bansal; Shiwani Chawla; Ritu Namdev

doi:10.2340/biid.v13.46956

Authors

Ruchi Singhal Department of Pediatric and Preventive Dentistry, Post Graduate Institute of Dental Sciences, Rohtak, Haryana, India https://orcid.org/0000-0002-5514-2482
Akshita Bansal Department of Pediatric and Preventive Dentistry, Post Graduate Institute of Dental Sciences, Rohtak, Haryana, India https://orcid.org/0009-0001-7890-3715
Shiwani Chawla Department of Pediatric and Preventive Dentistry, Post Graduate Institute of Dental Sciences, Rohtak, Haryana, India https://orcid.org/0009-0006-0003-5272
Ritu Namdev Department of Pediatric and Preventive Dentistry, Post Graduate Institute of Dental Sciences, Rohtak, Haryana, India https://orcid.org/0000-0003-3788-5298

DOI:

https://doi.org/10.2340/biid.v13.46956

Keywords:

Regenerative endodontics, revascularization, immature teeth, open apex, radiographic classification

Abstract

Purpose: To propose a radiographic classification system for evaluating outcomes of regenerative endodontic procedures (REPs) in immature necrotic permanent teeth.

Methods: A two-phase retrospective study was conducted. In Phase I, radiographs of 20 cases (2015–2018) were analyzed to identify patterns of apical closure, root lengthening, dentinal wall thickening, intracanal calcification, and periapical healing. Based on these findings, a six-class radiographic classification was proposed:
Class 1: Apical closure with increased root length and dentin thickness;
Class 2: Apical closure with increased root length only;
Class 3: Apical closure with increased dentin thickness only;
Class 4: Apical closure without changes in root length or dentin thickness;
Class 5: Barrier formation within the canal or coronal to the root end;
Class 6: No root dimensional changes with periapical healing of a documented pretreatment periapical radiolucency.
In Phase II, the classification was applied to 54 immature single-rooted permanent teeth from 44 patients aged 8–13 years treated with REPs between 2019 and 2023. Baseline and latest available follow-up radiographs were evaluated by two blinded examiners. Reproducibility was assessed using Cohen’s kappa, and associations with age and pre-treatment root stage were analyzed using Fisher’s exact test.

Results: Class 1 was most frequent. Partial intracanal calcification occurred in 35.18% of cases, with no complete canal obliteration. Age (p = 0.215) and pre-treatment root stage (p = 0.872) were not significantly associated with outcome classes. Inter- and intra-examiner agreement were high (κ = 0.82 and 0.86). All cases were accommodated within the six proposed categories, and no additional outcome classes were observed.

Conclusion: This proposed six-class radiographic framework demonstrated good internal reproducibility and may provide a structured basis for outcome reporting after REPs. Prospective multicenter validation is required.

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