Immature permanent teeth exhibiting pulpal necrosis present unique clinical challenges that differ significantly from those seen in mature dentitions, primarily due to open apices, thin dentinal walls, and compromised structural integrity during function. For decades, the standard of care for managing such teeth involved apexification procedures using calcium hydroxide or mineral trioxide aggregate (MTA) to induce apical barrier formation, thereby facilitating obturation. However, apexification techniques, although predictable in creating an apical stop, do not allow for continued root maturation, leaving the tooth structurally vulnerable. Recent advances in biologically based therapies have led to the emergence of regenerative endodontic procedures (REPs), which aim not only to resolve infection but also to stimulate tissue repair or regeneration within the root canal space, resulting in potential increases in root length, thickness of dentinal walls, and apical closure. A growing body of literature has revealed compelling advantages of regenerative approaches, especially in the context of restoring physiology, improving mechanical properties of the tooth, and reducing long-term fracture risk. Nonetheless, REPs remain clinically variable because of differences in case selection, disinfection protocols, scaffolds, and intracanal medicaments and because true regeneration versus repair is a topic of ongoing debate. The objective of this expanded review is to comprehensively compare the biological, clinical, radiographic, and long-term prognostic outcomes of regenerative endodontics and traditional apexification, drawing from contemporary evidence and clinical experience. Special emphasis is placed on procedural nuances, cellular biology, success metrics, limitations, and indications in modern endodontic practice. This article aims to be a thorough and academically rigorous narrative review to inform clinicians, researchers, and advanced dental students about current best practices and emerging directions in the management of immature necrotic teeth.
