Regenerative endodontic therapy is a tissue engineering based approach of treatment for endodontic disease. Its purpose is to achieve the regeneration of the pulp-dentin complex, thus to promote root development of the immature permanent tooth with necrotic pulp. Like other treatments based on tissue engineering techniques, the success of regenerative pulp therapy depends on such three elements as seed cells, scaffold materials and growth factors. Since its inception 20 years ago, there have been various terminologies in the literature, with similarities and differences in connotation. The present article summarizes and analyzes the term evolution, biological basis, clinical considerations and future scientific research directions of regenerative endodontics, in order to find out the unsolved scientific problems and to promote the development and standardization of this technique in clinical practice.
Dental Pulp ; Dental Pulp Necrosis ; Humans ; Regeneration ; Regenerative Endodontics ; Root Canal Therapy ; Tissue Engineering

Devitalization has been widely used in the root canal therapy of primary and permanent teeth in China more than ten years ago. With the development of local anesthetic drugs and injection technologies, this treatment method with high potential risks has been gradually abandoned. However, a questionnaire survey targeted all the participants at the 2018 China Pediatric Dentistry Conference showed that the devitalizer utilization proportion was still as high as 38.1% (383/1 005), even though the ratio was much lower than 75.5% (105/139) in 2003. These doctors had pay more attention to tissue burn caused by devitalizer marginal leakage or direct leakage, and know how to identify and handle with devitalizer burn. Devitalizers were usually made of arsenic trioxide, metal arsenic or paraformaldehyde, which have cytotoxicity, allergenicity, mutagenicity, carcinogenicity, and teratogenic effects on animals. Marginal leakage of devitalizers have high risks of causing soft and hard tissue necrosis. Most of the dentists have an understanding of the potential damages of arsenic containing devitalizers, so they will choose parafor maldehyde with relatively less toxicity. Paraformaldehyde has a certain self limitation, and there are few cases reported, so some dentists lack of vigilance. Paraformaldehyde can also causes tissue necrosis if leakage happens, and the treatment methods are similar to that of arsenic containing devitalizers. When handling with devitalizers burn, the necrosed soft and hard tissue, for example gingiva, alveolar bone or teeth that cannot keep, must be completely removed until fresh blood appears, then rinse with large amount of saline and seal with iodoform gauze. This paper described two cases of devitalizer burn during the root canal treatment of primary molars, both of the doctors failed to identify the devitalizer burn symptoms in the early stage, thus didn't do proper treatments immediately after burning. Resulting in the necrosis of large area of gingiva and alveolar bone, loss of primary molars and permanent tooth germs 1-2 months after devitalizer burn. This paper reported these two cases in detail in order to warn dentists the high risks of using any kind of devitalizers, help them learn how to identify and treat devitalizer burn, and remind them to stop using devitalizers as soon as possible.
Arsenic/toxicity* ; China ; Dental Pulp Devitalization ; Humans ; Necrosis ; Root Canal Therapy ; Tooth Germ ; Tooth Loss/chemically induced* ; Tooth, Deciduous

Dens invaginatus (DI) is a developmental anomaly as a result of a deepening or invagination of the enamel organ into the dental papilla during tooth development. In addition, DI is a malformation with varying anatomical features, which poses numerous challenges to treatment. Endodontic treatment of dens in dente is one of the most complica-ted cases of DI. Herein, an immature lateral incisor that employed regenerative endodontic treatment was presented. The mentioned tooth was diagnosed with DI, pulp necrosis, and chronic apical periodontitis. Hence, a favorable prognosis has been shown by a 2-year review with cone beam computed tomography. The tooth was functional with normal periodontal parameters and exhibited a normal response to the electric pulp sensibility test. Thus, regenerative endodontic treatment can also be recommended to endodontists for teeth with DI.
Humans ; Regenerative Endodontics ; Incisor/diagnostic imaging* ; Dens in Dente ; Dental Pulp Necrosis/therapy* ; Odontogenesis

Regenerative endodontic procedures (REPs) is a biologic-based treatment modality for immature permanent teeth diagnosed with pulp necrosis. The ultimate objective of REPs is to regenerate the pulp-dentin complex, extend the tooth longevity and restore the normal function. Scientific evidence has demonstrated the efficacy of REPs in promotion of root development through case reports, case series, cohort studies, and randomized controlled studies. However, variations in clinical protocols for REPs exist due to the empirical nature of the original protocols and rapid advancements in the research field of regenerative endodontics. The heterogeneity in protocols may cause confusion among dental practitioners, thus guidelines and considerations of REPs should be explicated. This expert consensus mainly discusses the biological foundation, the available clinical protocols and current status of REPs in treating immature teeth with pulp necrosis, as well as the main complications of this treatment, aiming at refining the clinical management of REPs in accordance with the progress of basic researches and clinical studies, suggesting REPs may become a more consistently evidence-based option in dental treatment.
Humans ; Consensus ; Regenerative Endodontics ; Dental Pulp Necrosis/therapy* ; Dentists ; Professional Role ; Dental Care

Pulpal and periapical diseases are the most prevalent dental conditions damaging the oral health of children in China. In view of China's national condition, the level of diagnosis and treatment for pulpal and periapical diseases of deciduous teeth is uneven and clinically there are inconsistent standards on the selection of operation methods for the endodontic treatment in deciduous teeth. Targeting these problems, the Society of Pediatric Dentistry, Chinese Stomatological Association organized experts from several famous universities and hospitals in China to carry out a panel discussion. The results of domestic and overseas researches and diagnosis and treatment experiences on dental pulp disease and periapical disease of deciduous teeth were also referred to. The present guideline was finally developed for the reference of dental clinicians.
Child ; Dental Care ; Dental Pulp ; Dental Pulp Necrosis ; Humans ; Periapical Diseases ; Tooth, Deciduous

BACKGROUND AND OBJECTIVES: Recombinant amelogenin protein (RAP) was reported to induce soft-tissue regeneration in canine infected endodontically treated permanent teeth with open apices. To characterize identities of the cells found in the RAP regenerated tissues compared to authentic pulp by identifying: 1) stem cells by their expression of Sox2; 2) nerve fibers by distribution of the axonal marker peripherin; 3) axons by their expression of calcitonin gene–related peptide (CGRP); 4) the presence of astrocytes expressing glial fibrillary acidic proteins (GFAP).METHODS: A total of 240 open-apex root canals in dogs were used. After establishment of oral contamination to the pulp, the canals were cleaned, irrigated, and 120 canals filled with RAP, and the other 120 with calcium hydroxide.RESULTS: After 1, 3, and 6 months, teeth were recovered for immune-detection of protein markers associated with native pulp tissues. Regenerated pulp and apical papilla of RAP group revealed an abundance of stem cells showing intense immunoreactivity to Sox2 antibody, immunoreactivity of peripherin mainly in the A-fibers of the odontoblast layer and immunoreactivity to CGRP fibers in the central pulp region indicative of C-fibres. GFAP immunoreactivity was observed near the odontoblastic, cell-rich regions and throughout the regenerated pulp.CONCLUSIONS: RAP induces pulp regeneration following regenerative endodontic procedures with cells identity by gene expression demonstrating a distribution pattern similar to the authentic pulp innervation. A- and C-fibers, as well as GFAP specific to astrocytic differentiation, are recognized. The origin of the regenerated neural networks may be derived from the Sox2 identified stem cells within the apical papilla.
Amelogenin ; Animals ; Astrocytes ; Axons ; Calcitonin ; Calcitonin Gene-Related Peptide ; Calcium Hydroxide ; Dental Pulp Cavity ; Dental Pulp Necrosis ; Dogs ; Gene Expression ; Glial Fibrillary Acidic Protein ; Nerve Fibers ; Odontoblasts ; Periapical Periodontitis ; Regeneration ; Stem Cells ; Tooth

OBJECTIVES: To achieve pulp-dentin complex regeneration with tissue engineering, treatment efficacies and safeties should be evaluated using in vivo orthotopic transplantation in a sufficient number of animals. Mice have been a species of choice in which to study stem cell biology in mammals. However, most pulp-dentin complex regeneration studies have used large animals because the mouse tooth is too small. The purpose of this study was to demonstrate the utility of the mouse tooth as a transplantation model for pulp-dentin complex regeneration research. MATERIALS AND METHODS: Experiments were performed using 7-week-old male Institute of Cancer Research (ICR) mice; a total of 35 mice had their pulp exposed, and 5 mice each were sacrificed at 1, 2, 4, 7, 9, 12 and 14 days after pulp exposure. After decalcification in 5% ethylenediaminetetraacetic acid, the samples were embedded and cut with a microtome and then stained with hematoxylin and eosin. Slides were observed under a high-magnification light microscope. RESULTS: Until 1 week postoperatively, the tissue below the pulp chamber orifice appeared normal. The remaining coronal portion of the pulp tissue was inflammatory and necrotic. After 1 week postoperatively, inflammation and necrosis were apparent in the root canals inferior to the orifices. The specimens obtained after experimental day 14 showed necrosis of all tissue in the root canals. CONCLUSIONS: This study could provide opportunities for researchers performing in vivo orthotopic transplantation experiments with mice.
Animals ; Biology ; Dental Pulp Cavity ; Dental Pulp Necrosis ; Edetic Acid ; Eosine Yellowish-(YS) ; Hematoxylin ; Humans ; Inflammation ; Male ; Mammals ; Mice ; Necrosis ; Pulpitis ; Regeneration ; Safety ; Stem Cells ; Tissue Engineering ; Tooth

Dens invaginatusis a rare malformation of the teeth, resulting in frequent pulp necrosis and chronic apical periodontitis. In this paper, the apical barrier technology was used to treat a case of chronic apical periodontitis caused by type Ⅱ dens invaginatus.
Dens in Dente ; Dental Pulp Necrosis ; Humans ; Incisor ; Periapical Periodontitis ; Root Canal Therapy

We report a clinical case of type Ⅲ dens invaginatus with endodontic-periodontal lesion in a maxillary lateral incisor. The palatal radicular anomaly predisposed the tooth to periodontal lesions. The caries along the palatal groove caused tooth pulp necrosis and periapical lesions. By means of microscopic root canal therapy, apical surgery, and guided periodontal tissue regeneration, the apical and periodontal infection were controlled, and the affected tooth was retained.
Dens in Dente ; Dental Pulp Necrosis ; Humans ; Incisor ; Root Canal Therapy

The present report presents a case of dens invaginatus (DI) in a patient with 4 maxillary incisors. A 24-year-old female complained of swelling of the maxillary left anterior region and discoloration of the maxillary left anterior tooth. The maxillary left lateral incisor (tooth #22) showed pulp necrosis and a chronic apical abscess, and a periapical X-ray demonstrated DI on bilateral maxillary central and lateral incisors. All teeth responded to a vitality test, except tooth #22. The anatomic form of tooth #22 was similar to that of tooth #12, and both teeth had lingual pits. In addition, panoramic and periapical X-rays demonstrated root canal calcification, such as pulp stones, in the maxillary canines, first and second premolars, and the mandibular incisors, canines, and first premolars bilaterally. The patient underwent root canal treatment of tooth #22 and non-vital tooth bleaching. After a temporary filling material was removed, the invaginated mass was removed using ultrasonic tips under an operating microscope. The working length was established, and the root canal was enlarged up to #50 apical size and obturated with gutta-percha and AH 26 sealer using the continuous wave of condensation technique. Finally, non-vital bleaching was performed, and the access cavity was filled with composite resin.
Abscess ; Bicuspid ; Dental Pulp Calcification ; Dental Pulp Cavity ; Dental Pulp Necrosis ; Female ; Gutta-Percha ; Humans ; Incisor ; Tooth ; Tooth Bleaching ; Ultrasonics ; Young Adult