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Concept: Ralph Frederick Sommer


The term “endo-perio” lesion has been proposed to describe the destructive lesion resulting from inflammatory products found in varying degrees in both the periodontium and the pulpal tissues. In most of the cases, clinical symptoms disappear following successful endodontic therapy. However failure after conventional root canal treatment calls for surgical intervention. A 35 year old male patient with endo-perio lesion in right maxillary lateral incisor was treated with platelet rich fibrin (PRF) and alloplastic bone substitute after conventional endodontic therapy. At the end of 6 months there was gain in clinical attachment, increased radiographic bone fill and reduction in probing depth which was maintained till 18 month follow-up. Present case report aims to evaluate the efficacy of PRF and alloplastic bone substitute in the management of intrabony defect associated with endo-perio lesion in maxillary lateral incisor because the healing potential of PRF and bone graft has not been widely studied in endodontics. The use of PRF allows the clinician to optimize tissue remodelling, wound healing and angiogenesis by the local delivery of growth factors and proteins. The novel technique described here enables the clinician to be benefited from the full regenerative capacity of this autologous biologic material.

Concepts: Wound healing, Extracellular matrix, Angiogenesis, Root canal, Endodontic therapy, Endodontics, Incisor, Ralph Frederick Sommer



The use of dentin preconditioning techniques in regenerative endodontic procedures is currently promising. Several growth factors have been detected on dentin after ultrasonic irrigation with EDTA. This study aimed to evaluate the effects of dynamic irrigation with different solution regimens on apical papilla cell (APC) attachment in an ex vivo immature tooth model.

Concepts: Immune system, Bacteria, Root canal, Endodontic therapy, Endodontics, Ralph Frederick Sommer



This study compared the efficacy of HyFlex NT (HF; Coltene, New York, NY) and Mani GPR (MN; Mani Inc, Tokyo, Japan) systems followed by a supplementary approach with passive ultrasonic irrigation (PUI) in removing the filling material from curved root canals during retreatment. The mesial canals from 20 extracted mandibular molars with Vertucci type IV configuration were instrumented and obturated (N = 40). Each mesial canal was retreated using either HF or MN instruments, alternating the system used per canal from root to root. The final preparation size was 40/0.04 for both systems. The volume of canal filling material was assessed by means of micro-computed tomographic (micro-CT) imaging before and after retreatment, and the working time was recorded. Canals still showing remnants of filling material were subjected to a supplementary approach with PUI, and another micro-CT scan was taken. The percentage of filling material removed with MN instruments and HF was similar (95.5% and 92.7%, respectively) (P > .05). MN required significantly less time to remove the filling material (P < .05). The supplementary approach with PUI significantly enhanced the removal of filling material (P < .05). Both systems were equally effective in removing the root canal filling during retreatment. MN was faster than HF. The supplementary approach with PUI significantly improved filling material removal.

Concepts: Root canal, Endodontic therapy, Irrigation, Canal, Remove, Irrigation district, Ralph Frederick Sommer, Filling


Regenerative endodontics has been defined as “biologically based procedure designed to replace damaged structures, including dentin and root structures, as well as cells of the pulp-dentin complex.” This is an exciting and rapidly evolving field of human endodontics for the treatment of immature permanent teeth with infected root canal systems. These procedures have shown to be able not only to resolve pain and apical periodontitis but continued root development, thus increasing the thickness and strength of the previously thin and fracture-prone roots. In the last decade, over 80 case reports, numerous animal studies, and series of regenerative endodontic cases have been published. However, even with multiple successful case reports, there are still some remaining questions regarding terminology, patient selection, and procedural details. Regenerative endodontics provides the hope of converting a nonvital tooth into vital one once again.

Concepts: Gene, Natural selection, Species, Root, Teeth, Root canal, Endodontics, Ralph Frederick Sommer


The goal of endodontics is to save teeth. Since inception, endodontic treatments are performed to obturate disinfected root canals with inert materials such as gutta-percha. Although teeth can be saved after successful endodontic treatments, they are devitalized and therefore susceptible to reinfections and fractures. The American Association of Endodontists (AAE) has made a tremendous effort to revitalize disinfected immature permanent teeth in children and adolescents with diagnoses including pulp necrosis or apical periodontitis. The American Dental Association (ADA) in 2011 issued several clinical codes for regenerative endodontic procedures or apical revascularization in necrotic immature permanent teeth in children and adolescents. These AAE and ADA initiatives have stimulated robust interest in devising a multitude of tissue engineering approaches for dental pulp and dentin regeneration. Can the concept of regenerative endodontics be extended to revitalize mature permanent teeth with diagnoses including irreversible pulpitis and/or pulp necrosis in adults? The present article was written not only to summarize emerging findings to revitalize mature permanent teeth in adult patients but also to identify challenges and strategies that focus on realizing the goal of regenerative endodontics in adults. We further present clinical cases and describe the biological basis of potential regenerative endodontic procedures in adults. This article explores the frequently asked question if regenerative endodontic therapies should be developed for dental pulp and/or dentin regeneration in adults, who consist of the great majority of endodontic patients.

Concepts: Teeth, Root canal, Endodontic therapy, Endodontics, Dentin, Pulp, American Dental Association, Ralph Frederick Sommer


Mineral trioxide aggregate (MTA) is a dental material used extensively for vital pulp therapy (VPT), scaffold cover during regenerative endodontic procedures, apical barrier in teeth with necrotic pulps and open apices, perforation repair, and root canal filling and root-end filling during surgical endodontics. A number of bioactive endodontic cements (BECs) have recently been introduced to the market. Most of these materials had calcium and silicate in their compositions; however, the bioactivity is the common property of these cements. These materials include: BioAggregate, Biodentine, BioRoot RCS, calcium enriched mixture (CEM) cement, Endo-CPM, Endocem, EndoSequence, EndoBinder, EndoSeal MTA, iRoot, MicroMega MTA,, MTA Bio, MTA Fillapex, MTA Plus, Neo MTA Plus, Ortho MTA, Quick-Set, Retro MTA, Tech Biosealer, and TheraCal. It has been claimed that these materials have properties similar to those of MTA but without the drawbacks. In Part I of this discussion we extensively reviewed available information on the chemical composition of the materials listed above and reported their applications for VPT. In this article the clinical applications of MTA and other BECs will be reviewed for apexification, regenerative endodontics, perforation repair, root canal filling, root-end filling, restorative procedures, periodontal defects and treatment of vertical and horizontal root fractures. In addition, the literature regarding the possible drawbacks of these materials after their clinical applications is reviewed. These drawbacks are including the materials' discoloration potential, systemic effects, and retreatability following use as a root canal filling. Furthermore, the current levels of evidence of these materials are also reported. Based on selected keywords, all publications were searched regarding the use of MTA as well as BECs for the rest of clinical applications. Additionally, the levels of evidence for MTA’s clinical applications and the newly introduced materials was evaluated through a scientometric study. Numerous publications were found regarding the use of BECs for various endodontic applications. The majority of these investigations compared BECs with MTA. Despite promising results of some materials, the number of publications using BECs for various clinical applications was very limited. Furthermore, most studies had several methodological shortcomings and low levels of evidence. This article is protected by copyright. All rights reserved.

Concepts: Root canal, Endodontic therapy, Endodontics, All rights reserved, Copyright, Portland cement, American Dental Association, Ralph Frederick Sommer


Treatment options for endodontic failure include nonsurgical or surgical endodontic retreatment, intentional replantation, and extraction with or without replacement of the tooth. The aim of the present study was to determine the impact of cone-beam computed tomographic (CBCT) imaging on clinical decision making among general dental practitioners and endodontists after failed root canal treatment. A second objective was to assess the self-reported level of difficulty in making a treatment choice before and after viewing a preoperative CBCT scan.

Concepts: Tomographic reconstruction, Decision theory, Decision making software, Root canal, Endodontic therapy, Endodontics, American Dental Association, Ralph Frederick Sommer


Data sourcesMedline, Cochrane CENTRAL databases; most recent two years of seven journals: (Acta Odontologica Scandinavica; Community Dentistry and Oral Epidemiology; Gerodontology; International Endodontic Journal; Journal of Endodontics; Journal of Oral Rehabilitation; and Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology).Study selectionTooth-based longitudinal prospective and retrospective studies, published in English from January 1950 to August 2013, assessing outcomes of NSRCT in adults with permanent teeth.Data extraction and synthesisStudies were independently selected and reviewed by two reviewers. Standardised items were extracted and compiled into a table of evidence. Study quality was assessed by the Wong Scale-Revised and those that scored less than 18 were excluded. Due to the high heterogeneity in reporting, meta-analysis was not conducted. All of the success criteria were implicitly based upon the presence or absence of apical pathology, and each individual study made internal comparisons of success using the same criteria.ResultsOf the twenty four studies selected, involving more than 17,430 teeth, nine were prospective and fifteen were retrospective studies. The overall mean study quality rating was 23(SD = 3) on the 27-point Wong Scale-Revised. Since the majority of the papers did not report raw numbers, and due to the heterogeneity in reporting, meta-analysis was not performed. In summary, eight prospective and fourteen retrospective studies reported no difference in outcomes, principally success which was defined by the absence of apical disease, with age. One prospective and one retrospective study reported an improvement in success with increasing age.ConclusionsThe moderate evidence indicated that increased patient age does not decrease the success of NSRCT.

Concepts: Epidemiology, Report, Root canal, Endodontic therapy, Endodontics, Dentistry, Ralph Frederick Sommer, Journal of Endodontics