Intentional tooth replantation (ITR) is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions. ITR is defined as the deliberate extraction of a tooth; evaluation of the root surface, endodontic manipulation, and repair; and placement of the tooth back into its original socket. Case reports, case series, cohort studies, and randomized controlled trials have demonstrated the efficacy of ITR in the retention of natural teeth that are untreatable or difficult to manage with root canal treatment or endodontic microsurgery. However, variations in clinical protocols for ITR exist due to the empirical nature of the original protocols and rapid advancements in the field of oral biology and dental materials. This heterogeneity in protocols may cause confusion among dental practitioners; therefore, guidelines and considerations for ITR should be explicated. This expert consensus discusses the biological foundation of ITR, the available clinical protocols and current status of ITR in treating teeth with refractory apical periodontitis or anatomical aberration, and the main complications of this treatment, aiming to refine the clinical management of ITR in accordance with the progress of basic research and clinical studies; the findings suggest that ITR may become a more consistent evidence-based option in dental treatment.
Humans ; Tooth Replantation/methods* ; Consensus ; Periapical Periodontitis/surgery*

Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

Objective To investigate the expression of Na +/Ca2 + exchanger 1(NCX1) channel protein in human odontoblasts(OD) and nervous tissue of dental pulp.Methods Twenty intact and healthy third molars extracted for orthodontic purpose were collected.The OD layer and nervous tissue were determined by dentin sialophosphoproteins(DSPP) antibody staining and modified Bielschowsky silver staining respectivelly.The immunohistochemical method was used to detect the expressions of NCX1 protein in human dental pulp tissue.The difference of expression of NCX 1 in human OD at different part of dental pulp was statistically analyzed using Image Pro Plus and SPSS software.Results NCX1 channel protein was mainly expressed on the cell body of OD,and nervous tissue of dental pulp.The expression level of NCX1 on the OD of crown pulp was higher(A=0.146±0.021) than that on the upper part of root pulp (A=0.120±0.034),but the expression difference was not significant(P＞0.05).Conclusions NCX1 channel protein was expressed on human OD and nervous tissue in dental pulp.