Levels of Evidence for the Outcome of Regenerative Endodontic Therapy

Correlation between pulp sensibility and magnetic resonance signal intensity following regenerative endodontic procedures in mature necrotic teeth- a retrospective cohort study

BACKGROUND

With increasing studies being published on regenerative endodontic procedures (REPs) as a treatment modality for mature necrotic teeth, the assessment of outcomes following regenerative endodontic procedures has become more challenging and the demand for a better understanding of the regenerated tissues following this treatment is rising. The study aimed to correlate cold, electric pulp testing (EPT), and magnetic resonance imaging (MRI) signal intensity (SI) in mature necrotic teeth treated with regenerative endodontic procedures.

METHODOLOGY

This retrospective cohort study included eighteen adult patients who experienced tooth necrosis in mature maxillary anterior teeth recruited from the outpatient clinic, Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt from July 2017 until December 2018 with 12 months of follow-up. regenerative endodontic procedures via blood clot were performed. The canals were instrumented by ProTaper Next (PTN) files until final sizes X3 or X5. Biodentine was used as cervical plug material. Pre and post-operative clinical follow-up was done where the patients' responses to cold and electric pulp testing were given a scoring system and were compared to the normal contralateral tooth. Pre and post-operative magnetic resonance imaging signal intensity of both the involved tooth and its contralateral at the middle and the apical thirds of the root canals were assessed after 3, 6, and 12 months. Data was analyzed using the ANOVA, Friedman and Bonferroni tests. Significance was set at a p-value < 0.05.

RESULTS

All 18 teeth scored a baseline score of "2" for cold and electric pulp testing. There was a significant difference between scores of the cold test at baseline and 12-month follow-up (p < 0.001). There was a significant difference between scores of the electric pulp testing of baseline and 12-month follow-up (p < 0.001). There was a moderately significant indirect (inverse) correlation between magnetic resonance imaging signal intensity and cold test in both the middle and apical thirds at 12 months. No significant correlations were detected between magnetic resonance imaging signal intensity and electric pulp testingat any of the time intervals (p > 0.05).

CONCLUSION

Magnetic resonance imaging is a successful non-invasive method to assess outcomes of regenerative endodontic procedures and correlating it with another reliable method of assessing pulpal responses, cold test, could validate these outcomes.

CLINICAL TRIAL REGISTRATION

The study was registered with ClinicalTrials.gov (ID: NCT03804450).

Histologic and radiological observations of a human immature premolar with pulp necrosis treated with regenerative endodontic procedure - A case report of a four-year follow-up

Background

Reports are found on long-term radiographic follow-up of teeth treated with regenerative endodontic techniques, but scarce literature is observed regarding the tissue formed in the root canal. A four-year radiographic follow-up with histologic findings in an immature mandibular premolar with dens evaginatus that underwent a regenerative endodontic procedure (REP) is presented here. After four years following REP, the tooth was extracted for orthodontic purposes thereby presenting an opportunity to report the histologic findings.

Summary

The radiographic changes included a slight root lengthening and thickening and apex closure. Histologic evaluation revealed a fibrous connective tissue with an inflammatory infiltrate in the canal space. In the apical region, cementum-like irregular mineralization developed toward the center, giving the appearance of a closed apex. Root thickening, increase in length, and radiographic closure of the apex occurred due to cemental hyperplasia.

Conclusion

After 4 years following REP in an immature mandibular premolar with apical periodontitis, granulation tissue had formed in the root canal, indicating repair and not regeneration.

Effect of rapamycin on human periodontal ligament stem cells that have been exposed to sodium hypochlorite

AIMS

The present study investigated the effect of rapamycin on the viability and osteogenic differentiation potential of human periodontal ligament stem cells (hPDLSCs) in the presence of sodium hypochlorite (NaOCl).

MAIN METHODS

After determining the minimum inhibitory concentration of NaOCl and optimum concentration of rapamycin, the viability of hPDLSCs was evaluated using the MTT assay subsequent to their exposure to NaOCl, rapamycin, or a combination of both. Osteogenic differentiation was evaluated by the cell mineralization assay performed by alizarin red S staining, alkaline phosphatase activity, and monitoring the expression of osteogenic genes markers Runt-related transcription factor 2, osteocalcin, and osteoprotegerin, using real-time quantitative polymerase chain reaction (RT-qPCR). The expression of autophagy-related genes PI3K, Akt, and mTOR, was also analyzed with RT-qPCR.

KEY FINDINGS

Stem cells treated with rapamycin showed the highest percentage of viable cells in the presence of NaOCl. The same trend was observed for all osteogenic differentiation assays. The hPDLSCs treated with rapamycin demonstrated the highest calcium nodule deposition, alkaline phosphatase activity, and the expression of osteogenic gene markers. These effects were not adversely affected by the presence of NaOCl. Rapamycin significantly inhibited mTOR gene expression, while there were no differences in the gene expression of PI3K and Akt.

SIGNIFICANCE

Rapamycin counteracts the cytotoxic effect of NaOCl by enhancing the viability and osteogenic differentiation potential of hPDLSCs. Rapamycin appears to accomplish these processes via autophagy activation, by inhibiting mTOR gene expression. The incorporation of rapamycin in regenerative endodontic therapy may encourage a higher success rate.

Outcomes reporting in systematic reviews on revitalization: A scoping review for the development of a core outcome set

BACKGROUND

Revitalization is a type of regenerative endodontic treatment (RET) that offers the exciting prospect of revitalizing damaged tissue, therefore improving outcomes for non-vital immature teeth. To evaluate its potential, there needs to be consistency in outcome reporting of clinical studies investigating revitalization to allow for evidence synthesis and inform clinical decision making.

OBJECTIVES

The aim of this scoping review was to identify outcomes that are reported in systematic reviews on revitalization including how and when these outcomes are measured. Additionally, evidence of selective reporting bias in the reviews was assessed.

METHODS

A comprehensive electronic search of healthcare databases and grey literature was conducted to identify systematic reviews published in the English language reporting outcomes of revitalization in permanent immature teeth. There was no restriction on the date of publication. Outcome data was extracted by four reviewers independently and mapped with a healthcare taxonomy into five core areas: survival, clinical/physiological changes, life impact, resource use and adverse events. Selective reporting bias and how it was measured was assessed independently by two reviewers.

RESULTS

Twenty-six systematic reviews were included in this scoping review. There was lack of standardization in reporting and significant heterogeneity across reviews in outcome endpoints. The outcomes reported could be aligned within the five core areas of the taxonomy including tooth survival which was reported in nine reviews. Patient-reported outcomes were generally limited and no review reported on Oral Health Related Quality of Life. Many of the reviews reporting on randomized control trials were at low risk of selective reporting bias whilst other study designs were at higher risk.

DISCUSSION

Consistency in outcome reporting is necessary to realize the benefits of old but particularly novel therapies. Data from this review confirmed heterogeneity in reporting outcomes of revitalization and the need for development of a core outcome set (COS).

CONCLUSIONS

Several important outcomes including survival, root development, tooth discolouration and periapical healing have been identified in this review which could inform the development of a COS in this area.

REGISTRATION

Core Outcome Measures in Effectiveness Trials (COMET) database (registration no. 1879).

Clinical and radiographic outcomes of regenerative endodontic treatment performed by endodontic postgraduate students: a retrospective study

Objectives

Regenerative endodontic treatment is a clinical procedure aimed at biologically regenerating damaged root canal tissue of immature permanent teeth. This study aimed to report the outcomes of regenerative endodontic treatment performed by endodontic postgraduate students.

Materials and Methods

Clinical and radiographic data of 27 patients, aged 10–22 years, who underwent regenerative treatment of immature permanent teeth from 2015 to 2019 were followed up, wherein clinical and radiographic examinations were performed for each patient. Postoperative success rate and tooth survival were analyzed, and the postoperative radiographic root area changes were quantified.

Results

A total of 23 patients attended the dental appointments, showing that all teeth survived and were asymptomatic. Specifically, 7 periapical pathosis cases were completely healed, 12 were incompletely healed, and 4 cases failed. Moreover, significant differences were found between discolored and non-discolored teeth, and between the presence or absence of periapical radiolucency. Additionally, 3 anterior teeth showed complete closure of the apical foramen, while the apical foramen width was reduced in 17 teeth and failed in 3 teeth. Root length was also found to have been increased in 7 anterior and 4 posterior teeth, and the average length ranged from 4.00–0.63 mm in the anterior teeth, 2.85–1.48 mm of the mesial root, and 2.73–2.16 mm of the molar teeth distal root. Furthermore, calcified tissue deposition was observed in 7 teeth.

Conclusions

A favorable outcome of regenerative endodontic treatment of immature permanent teeth with necrotic pulp was achieved with a high survival rate.

Comparing Antibiotic Pastes with Electrospun Nanofibers as Modern Drug Delivery Systems for Regenerative Endodontics

Nanomaterials have various features that make these types of materials able to be applied in different biomedical applications like, diagnosis, treatment, and drug delivery. Using such materials in endodontic filed both to face the challenges that occur during treatment processes and to make these materials have an antibacterial effect without showing any harm on the host cells. The approach of nanofibers loaded with various antibacterial drugs offers a potential treatment method to enhance the elimination procedure of intracanal biofilms. Clinically, many models of bacterial biofilms have been prepared under in vitro conditions for different aims. The process of drug delivery from polymeric nanofibers is based on the principle that the releasing ratio of drug molecules increases due to the increase in the surface area of the hosted structure. In our review, we discuss diverse approaches of loading/releasing drugs on/from nanofibers and we summarized many studies about electrospun nanofibers loaded various drugs applied in the endodontic field. Moreover, we argued both the advantages and the limitations of these modern endodontic treatment materials comparing them with the traditional ones.

A Prospective Study of Long-Term Regenerative Endodontics Outcomes of Necrotic Immature Permanent Teeth: An 8-Year Follow-Up

For the management of necrotic immature teeth, regenerative endodontics offers the advantage of further root lengthening, thickening of dentin wall, and apical closure. This prospective study aimed to evaluate the long-term outcome of regenerative endodontics in immature necrotic permanent teeth. A total of 23 immature roots were medicated by triple antibiotic paste. After 21 days, bleeding was induced by over-instrumentation, and then mineral trioxide aggregate and coronal restoration were applied. Patients were scheduled for clinical and radiographic follow-up for 8 years. The radiographic changes of root dimensions were assessed using the ImageJ Plugin and statistically analyzed by Kruskal-Wallis test at a 95% confidence level. For qualitative evaluation, images were overlapped and analyzed using Photoshop software. All teeth were asymptomatic one month after the treatment. All teeth (n = 18) with preoperative periapical radiolucency showed complete resolution within 6-9 months. Recall rate at two, three, and eight years was 69.6%, 56.5%, and 34.8%, respectively. Continuous root development with a significant increase in root length and thickening of dentin wall accompanied by a significant decrease in apical canal diameter was seen at the end of the observation period (p < 0.001). In conclusion, the long-term outcome of regenerative endodontics revealed successful clinical and radiographic results with appropriate case selection.

Knowledge, Attitude, and Perception Among Endodontists Toward Regenerative Endodontics: A Cross-sectional Survey of Four Indian Universities

Background:

Regenerative endodontics is a rapidly developing field in dentistry. However, the regenerative endodontic procedures are not familiar to many clinicians in India.

Aim:

This survey aimed at assessing the level of knowledge, attitude, and perception (KAP) among endodontists toward regenerative endodontics.

Materials and Methods:

A cross-sectional survey was conducted in the year 2019 to collect data. A questionnaire to collect data on KAP toward regenerative endodontics was administered to 49 faculty and 69 postgraduate students of endodontics from four universities. The Chi-Square test and logistic regression were applied to study the association between KAP and demographic variables. Spearman's rho was computed to study the correlation between KAP scale scores of the participants. The data were analyzed by using Statistical Package for the Social Sciences software program (SPSS), version 15.0 (South Asia, Bangalore).

Results:

The survey yielded an overall response rate of 81%. Less than 50% of the participants had sound knowledge, 65% had a positive attitude, and only 21% had a positive perception about Regenerative Endodontic Procedures (REPs). Most of the participants (86.5%) were of the opinion that regenerative therapies should be a part of dentistry. Majority of the participants (89.6%) were inclined to receive training in REPs. About 80% of the participants felt that the higher cost of treatment is a significant hurdle for patients to accept REPs. Less than half the participants (41.7%) were using REPs in their clinical practice, such as the use of membranes, scaffolds, and revascularization.

Conclusion:

Endodontists have a positive attitude toward the use of regenerative therapies. However, there is a deficiency of training in REPs in dental colleges.

Clinical cell-based versus cell-free regenerative endodontics: clarification of concept and term

There is no consensus on the true meaning of clinical regenerative endodontics, and there is confusion over the concept and the term. Commonly used terms include revitalization and revascularization. The clinical methods for endodontic revitalization procedures and the tissue engineering concept differ depending on whether there is exogenous delivery of cells - called cell therapy, or not. Here, in this review, the difference is clarified by emphasizing the correct terminology: cell-free versus cell-based regenerative endodontic therapy (CF-RET versus CB-RET). The revitalization procedures practised clinically do not fit into the modern tissue engineering concepts of pulp regeneration but can be categorized as CF-RET. The modern tissue engineering concept in pulp regeneration is a CB-RET, which so far is at the clinical trial stage. However, histological examination of teeth following regenerative endodontic treatments reveals healing with repair derived from stem cells that originate from the periodontal, bone and other tissues. The aim of regenerative endodontics is regeneration of the pulp-dentine complex. This review discusses why CF-RET is unlikely to regenerate a pulp-dentine complex with current protocols. The American Association of Endodontists and the European Society of Endodontology have not yet recommended autologous stem cell transplantation (CB-RERT) which aspires for regeneration. Therefore, an understanding of the concept, term, difficulties and differences in current protocols is important for the clinician. However, rather than being discouraged that ideal regeneration has not been achieved to date, repair can be an acceptable outcome in clinical regenerative endodontics as it has also been accepted in medicine. Repair should also be considered in the context that resolution of the clinical signs/symptoms of pulp necrosis/apical periodontitis is generally reliably obtained in clinical regenerative endodontics.

Regenerative Endodontic Procedures: An Umbrella Review

The Regenerative Endodontic Procedure (REP) is a biologically based method in which a damaged pulp-dentin complex is replaced by a new vital tissue. This umbrella review aimed to critically assess the available systematic reviews (SRs) on REP. An electronic database search was conducted (PubMed-Medline, CENTRAL, Scielo, Web of Science, and LILACS) until December 2020. Studies were included if they were an SR on REP. The Risk of Bias (RoB) of SRs was analyzed using the Measurement Tool to Assess SRs criteria 2 (AMSTAR2). The primary outcome was the methodological quality in each specific section of REP protocols and outcomes. From 403 entries, 29 SRs were included. Regarding the methodological quality, ten studies were of critically low, three of low, fourteen of moderate, and two were rated as high quality. The quality of evidence produced by the available SRs was not favorable. Future high standard SRs and well-designed clinical trials are warranted to better elucidate the clinical protocols and outcomes of REP.

Regenerative Endodontic Procedures, Disinfectants and Outcomes: A Systematic Review

AIMS

This systematic review aims to identify and synthesise available evidence to determine the clinical and radiographic outcomes of REP involving any disinfection irrigant together with a non-antibiotic intracanal medicament.

METHODS

Experimental and observational studies evaluating the outcomes of REP in immature non-vital permanent teeth in 6-16 year olds, where the protocol used any type of disinfectant irrigant together with a non-antibiotic intracanal medicament (non-setting calcium hydroxide) were included. Data was narratively synthesised and presented in respect to the primary outcome (elimination of symptoms and infection) and secondary outcomes (increase in root length/width; positive response to vitality testing; patient-reported outcomes; adverse effects).

MAIN FINDINGS

1628 studies were identified, of which five met the eligibility criteria for inclusion in the review. Studies included one randomised control trial and four observational studies. All five studies showed an absence of clinical signs and symptoms for all teeth postoperatively with radiographic resolution or absence of pathology following the disinfection stages of the REP used. Choice of secondary outcomes were inconsistent but included further root development, coronal discolouration and root canal calcifications postoperatively. There was a high risk of bias in all five studies and subsequently the quality of the evidence base was judged to be low.

PRINCIPLE CONCLUSIONS

REP using a non-antibiotic disinfectant approach appears capable of providing satisfactory outcomes for a non-vital immature permanent tooth. Further high-quality research is required before solid recommendations towards clinical practice guidelines for the disinfection portion of REP can be implemented.

Effect of Intracanal Medicaments and Irrigants on the Release of Transforming Growth Factor Beta 1 and Vascular Endothelial Growth Factor from Cervical Root Dentin

INTRODUCTION

This study aimed to evaluate (1) the effect of irrigating solutions and intracanal medicaments on the release of transforming growth factor beta 1 (TGF-β1) and vascular endothelial growth factor (VEGF) from cervical root dentin and (2) the effect of associating triple antibiotic paste (TAP) and calcium hydroxide paste (CH) with 2% chlorhexidine (CHX) on TGF-β1 release.

METHODS

First, 119 specimens from roots (cervical thirds) were obtained and were distributed into 5 groups: 2% CHX, 2.5% sodium hypochlorite, TAP, CH, and 10% EDTA by each growth factor (TGF-β1 [n = 8] and VEGF [n = 8]). Then, specimens were distributed as follows (n = 13): TAP + 2% CHX, CH + 2% CHX, and 10% EDTA and treated with irrigating solutions and intracanal medicaments. After the treatments, the specimens were immersed in 10% EDTA (20 minutes), and the solution was analyzed using the enzyme-linked immunosorbent assay. The data were submitted to normality, homogeneity of variance, and Mann-Whitney tests (P < .05).

RESULTS

Significant differences were found between the irrigating solutions (P < .05) and intracanal medicaments for TGF-β1 (P < .05). No VEGF release was detected for any group. Our results showed no significant differences among the TAP + 2% CHX and EDTA groups for TGF-β1 but a significant difference between CH + 2% CHX and the other groups (P < .05).

CONCLUSIONS

The use of 2% CHX as the irrigating solution, CH as the intracanal medicament, and 10% EDTA as the final irrigation provides higher TGF-β1 release from the cervical root dentin, whereas VEGF was not detected. Moreover, TAP and 2% CHX with 10% EDTA as the final irrigation resulted in greater TGF-β1 release from cervical root dentin than CH + 2% CHX.

Clinical Outcomes of Immature Teeth Treated with Regenerative Endodontic Procedures-A San Antonio Study

INTRODUCTION

Factors that influence clinical outcomes for regenerative endodontic procedures (REPs) are unknown. This retrospective study aimed to assess tooth healing, root development, pulp vitality, and esthetics post-REPs and categorize them into clinician- and patient-centered outcomes. Furthermore, this study identified significant predictors affecting such outcomes.

METHODS

Immature permanent teeth diagnosed with pulp necrosis treated with REPs between 2008 and 2018 with a minimum of 1-year follow-up were included. Outcomes included success and survival rates, changes in root development using 2-dimensional radiographic root area (RRA) and 3-dimensional measurements, pulp vitality, and tooth discoloration. Predictor variables of success included age, sex, etiology of pulp necrosis (PN), type of medicament, sodium hypochlorite (NaOCl) concentration, type of biomaterial used over the blood clot, and preoperative apical diagnosis. Statistical analyses included Cox proportional hazard analyses and generalized regression models.

RESULTS

Fifty-one teeth with an average of 2.1 years of follow-up satisfied the criteria. The survival rate was 92%. The success rate was 84.3% with age, etiology of PN, type of medicament, and NaOCl concentration being significant predictors of failure. Root development occurred in 91.4% of cases with age, sex, etiology of PN, type of medicament, NaOCl concentration, and apical diagnosis being significant predictors for RRA change. Positive pulp sensibility responses were associated with greater RRA change, and, finally, the type of biomaterial was a significant predictor for tooth discoloration after treatment.

CONCLUSIONS

REPs provide a high survival rate. Patient and clinical factors may affect outcomes, and this knowledge may help to define the criteria for optimal treatment planning of REPs.

Knowledge, attitudes, and practices of undergraduate students concerning Regenerative Endodontics

BACKGROUND

Knowledge, attitudes, and beliefs of the students are important for the Tissue Engineering in Endodontic practice. The opinion of these future dentists would ultimately will decide the endurance of REPs as routine procedures in endodontic practice. The aim of this study was to perform a survey to identify the knowledge, attitudes, and practices of undergraduate students about regenerative endodontic procedures (REPs).

METHODS

The questionnaire was obtained after cross-cultural adaptation of a questionnaire previously applied in USA and was applied to two hundred forty-eight undergraduates. Data were statistically analyzed.

RESULTS

Most of the students (82.9%) agreed that regenerative therapy should be incorporated to dentistry and 87.5% of them believed that stem cells banks would be useful for the tissue regeneration. Most participants (58.1%) would like to obtain an internship/tutoring that addresses REPs and 80.8% of participants think that the major obstacle to a patient accepting a REP was the expected high cost of the treatment. The freshmen students were more optimistic about offering stem cell treatments to their patients (P≤0.05).

CONCLUSIONS

The undergraduates were very optimistic about the future of REPs, stem cell banking, and tissue engineering. Although seniors demonstrated less enthusiasm towards REPs than the freshman, most students are willing to recommend these treatments to their patients.

Revitalisation endodontic treatment of traumatised immature teeth: a prospective long-term clinical study

PURPOSE

Continuation of root development following revitalisation endodontics (RET) has been shown to be unpredictable with lower success rates in traumatised teeth. This study reports the outcomes for RET in traumatised teeth over a review period of 4 years.

METHODS

A prospective uncontrolled study, where RET was performed on traumatised upper immature anterior teeth with necrotic pulps in 15 children (mean age = 8.3 years), was conducted. Patients were reviewed at 3, 9, 12, 24, and 48 months, where clinical and radiographic assessments were performed. At the last review appointment, patients and parents answered questions assessing their perception and acceptance of tooth colour change over time. McNemar's Exact test and linear mixed model assessment were used to assess changes in pulpal electrical response and radiographic evidence of continuation of root development over time, respectively.

RESULTS

There was 83.3% healing with no significant changes in EPT responses, and no significant changes in root lengths, while significant changes in root widths (p < 0.05) and root apex widths (p < 0.001) were found over time. Twenty-five percent of patients and 33% of parents felt that there were changes in tooth colour following RET over time.

CONCLUSION

Within the limitations of this study, traumatised teeth treated using RET showed no significant root lengthening, however, acceptable periapical healing, slow thickening of root dentinal walls, and rapid development of apical closure were evident over a period of 43 months. Using Portland cement and omitting minocycline, did not eliminate crown colour change following RET.

Regenerative endodontics: a comprehensive review

The European Society of Endodontology and the American Association for Endodontists have released position statements and clinical considerations for regenerative endodontics. There is increasing literature on this field since the initial reports of Iwaya et al. (Dental Traumatology, 17, 2001, 185) and Banchs & Trope (Journal of Endodontics, 30, 2004, 196). Endogenous stem cells from an induced periapical bleeding and scaffolds using blood clot, platelet rich plasma or platelet-rich fibrin have been utilized in regenerative endodontics. This approach has been described as a 'paradigm shift' and considered the first treatment option for immature teeth with pulp necrosis. There are three treatment outcomes of regenerative endodontics; (i) resolution of clinical signs and symptoms; (ii) further root maturation; and (iii) return of neurogenesis. It is known that results are variable for these objectives, and true regeneration of the pulp/dentine complex is not achieved. Repair derived primarily from the periodontal and osseous tissues has been shown histologically. It is hoped that with the concept of tissue engineering, namely stem cells, scaffolds and signalling molecules, that true pulp regeneration is an achievable goal. This review discusses current knowledge as well as future directions for regenerative endodontics. Patient-centred outcomes such as tooth discolouration and possibly more appointments with the potential for adverse effects needs to be discussed with patients and parents. Based on the classification of Cvek (Endodontics and Dental Traumatology, 8, 1992, 45), it is proposed that regenerative endodontics should be considered for teeth with incomplete root formation although teeth with near or complete root formation may be more suited for conventional endodontic therapy or MTA barrier techniques. However, much is still not known about clinical and biological aspects of regenerative endodontics.

Regenerative Endodontic Procedures among Endodontists: A Web-based Survey

INTRODUCTION

The protocols that endodontists implement for regenerative endodontic procedures (REPs) are unknown. The aim of this study was to examine current REP protocols among practicing endodontists in the United States.

METHODS

A Web-based survey was sent to 4060 active members of the American Association of Endodontists (AAE). A total of 850 participants completed the survey, representing a 20.9% response rate.

RESULTS

Responses indicated 60% reported having performed REPs; most performed 1 to 3 per year. The most commonly selected source (60.8%) for the clinical protocol was the "AAE Clinical Considerations for a Regenerative Procedure." Time constraints were the most common reason why 92.4% of respondents did not report their REP cases to the AAE.org database; additionally, 15.5% were unaware of it. Almost half (49.8%) of the participants reported they would attempt an REP on a patient of any age. The most commonly used irrigants were >3% sodium hypochlorite at the first appointment and EDTA at the scaffold formation appointment. As the intracanal medicament, 52.2% used calcium hydroxide, whereas 23.5% used triple antibiotic paste. At the scaffold formation appointment, 77.1% used a local anesthetic without a vasoconstrictor, and 94.3% used a blood clot as the scaffold. Mineral trioxide aggregate was the coronal barrier most often selected. Considering factors most likely to encourage the use of REPs in the future, 79.8% reported the availability of good candidates followed by 40.1% who desired better evidence.

CONCLUSIONS

Based on the results of this survey, REP protocols appear to be heterogeneous and do not strictly conform to the "AAE Clinical Considerations for a Regenerative Procedure."

A review of regenerative endodontics: current protocols and future directions

This review outlines the biological basis and clinical protocols currently used in regenerative endodontic procedures (REPs) and discuss future directions in pulp regeneration approaches. The treatment of immature teeth with REPs has been described as a ‘paradigm shift’ as there is the potential for further root maturation. Clinically, REPs involve disinfection of the root canal system without damaging the endogenous stem cell potential present in the apical papilla and other tissues. These stems cells are introduced into the root canal space by inducing a blood clot followed by placement of an intracanal barrier to prevent microleakage. The biological concept of REPs involves the triad of stem cells, scaffold and signalling molecules. Currently, repair rather than true regeneration of the ‘pulp-dentine complex’ is achieved and further root maturation is variable. However, may clinicians consider the treatment of teeth with REPs as the optimal treatment approach for immature teeth with pulp necrosis.

A prospective clinical study of regenerative endodontic treatment of traumatized immature teeth with necrotic pulps using bi-antibiotic paste

AIM

To evaluate the treatment outcomes of a revitalization endodontic technique (RET) for the management of traumatized immature teeth with necrotic pulps in children.

METHODOLOGY

Fifteen healthy children (age range = 7-10 years) with traumatized immature maxillary incisors with necrotic pulps treated with bi-antibiotic revitalization endodontic technique were prospectively assessed over approximately two years (mean = 22 months). One operator undertook all treatments, clinical reviews and standardized radiographic exposures with radiographic analysis being carried out by two calibrated experienced clinicians. Crown colour change was assessed using an objective published methodology. Wilcoxon signed-rank test was used to compare root lengths, root dentinal widths and apical foramen widths over time.

RESULTS

Interoperator measurement reliability was consistently strong for all measurements. There was no significant difference in root lengths or root dentinal wall widths following RET. A significant difference in apical foramen widths was observed after 2 years (P = 0.013) with resolution of clinical signs of infection in all cases. Despite omitting minocycline and using Portland cement (nonbismuth containing cement), a noticeable crown colour change (yellower, redder and lighter), as measured by an objective colour measurement system with ΔE = 7.39, was recorded. Most patients, however, were satisfied with the aesthetic outcome.

CONCLUSION

Traumatized immature teeth with necrotic pulps treated with revitalization endodontic technique did not demonstrate continuation of root development or dentine formation when assessed by periapical radiographs. However, apical closure and periodontal healing were observed. A measurable change in crown colour (yellower, redder and lighter), with mostly no aesthetic concern to the patients/parents, was also observed.

Root Canal Filling after Revascularization/Revitalization

INTRODUCTION

Revascularization/revitalization therapy is considered an alternative procedure for management of teeth with an immature apex and necrotic pulp, mainly when root development is interrupted in the early phases of formation. However, this clinical treatment protocol should be considered a permanent procedure?

METHOD

A maxillary central incisor with a previous and successful RR treatment was intentionally filled with a biocompatible material with the periapical tissues due to the patient's lack of adherence to the follow-up protocol.

RESULTS

The 20-month follow-up showed absence of clinical, radiological and tomographic signs and symptoms of an endodontic re-infection.

CONCLUSION

This case demonstrates that once the increased thickening of the canal walls, incrementing the root length, apical closure and the total resolution of the apical lesion are observed, the main canal of a previously treated tooth with an RR procedure can be filled.

Regenerative Endodontic Treatment versus Apical Plug in Immature Teeth: Three-Year Follow-Up

This report compares and evaluates the treatment outcomes of regenerative endodontic treatment and apical plug as two accepted treatment protocols in a pair of necrotic immature maxillary central incisors of a 12-year old female. The patient was referred complaining of a dull pain and swelling in her upper lip area. She had a history of trauma to the anterior maxilla two years earlier. Both teeth were clinically diagnosed with pulp necrosis and periapical radiographs revealed that separate periapical radiolucent lesions surrounded the immature apices of both teeth. The left and right incisors were treated with apical plug and regenerative endodontic treatment, respectively, using calcium-enriched mixture (CEM) cement. The patient was followed-up for three years. During this period, both teeth were clinically asymptomatic and showed complete radiographic healing of the periapical lesions. The right central incisor showed root development. No tooth discoloration was evident. Apexification by apical plug placement and pulp regeneration are both reliable treatments for immature non-vital teeth. In order to choose the right treatment the advantages of either technique should be weighed against its drawbacks. CEM cement can be successfully applied for both purposes. This biomaterial causes less discoloration of the tooth.

Regenerative endodontics: a true paradigm shift or a bandwagon about to be derailed?

Aims

Regenerative endodontic techniques (RETs) have been hailed as a paradigm shift for the management of traumatised non-vital immature permanent anterior teeth. In this article the aim was to critically appraise the literature with regards to the outcome of regenerative endodontics on root development.

Methods

Critical review of the literature where regenerative endodontic techniques have been used in the management of immature non-vital teeth with continuation of root development as the main outcome reported.

Results

Most studies published were in the form of case reports and series with very few randomised controlled trials with a high risk of bias. Continuation of root development following the use of RET has been shown to be unpredictable at best with lower success in those teeth losing vitality as a result of dental trauma.

Conclusions

Despite the high success of regenerative endodontics in terms of periodontal healing including resolution of clinical and radiographic signs and symptoms of infection, continuation of root development remains an unpredictable outcome. The use of a blood clot as a scaffold in regenerative endodontics should be reviewed carefully as that might offer an environment for repair rather than regeneration. In addition, preservation of structures, such as Hertwig’s epithelial root sheath, may have an important bearing on the success of this approach and should be further investigated.

Pulpo-Periodontal Regeneration: Management of Partial Failure Revascularization

The aim of this work is to present a case of management of an open apex on a lower molar by using tissue engineering, with two endodontic procedures in the same tooth. We had to resort to pulp regeneration on the distal root and apexification with MTA on the mesial roots after the failure of regenerative therapy on those ones. The management consisted in scheduling regular follow-ups combined with X-rays. After 24 months, the radiological control has shown pulpo-periodontal regeneration associated with walls thickening and distal root elongation and periapical ad integrum healing.

Critical Assessment of Search Strategies in Systematic Reviews in Endodontics

INTRODUCTION

The aim of this study was to perform an overview of literature search strategies in systematic reviews (SRs) published in 2 endodontic journals, Journal of Endodontics and International Endodontic Journal.

METHODS

A search was done by using the MEDLINE (PubMed interface) database to retrieve the articles published between January 1, 2000 and December 31, 2015. The last search was on January 10, 2016. All the SRs published in the 2 journals were retrieved and screened. Eligible SRs were assessed by using 11 questions about search strategies in the SRs that were adapted from 2 guidelines (ie, AMSTAR checklist and the Cochrane Handbook).

RESULTS

A total of 83 SRs were retrieved by electronic search. Of these, 55 were from the Journal of Endodontics, and 28 were from the International Endodontic Journal. After screening, 2 SRs were excluded, and 81 SRs were included in the study. Some issues, such as search of grey literature and contact with study authors, were not fully reported (30% and 25%, respectively). On the other hand, some issues, such as the use of index terms and key words and search in at least 2 databases, were reported in most of the SRs (97% and 95%, respectively). The overall quality of the search strategy in both journals was 61%. No significant difference was found between the 2 journals in terms of evaluation criteria (P > .05).

CONCLUSIONS

There exist areas for improving the quality of reporting of search strategies in SRs; for example, grey literature should be searched for unpublished studies, no language limitation should be applied to databases, and authors should make an attempt to contact the authors of included studies to obtain further relevant information.

Long-Term Follow-Up of a Revascularized Immature Necrotic Tooth Evaluated by CBCT

This case study reports the successful treatment of an immature upper premolar with periapical pathosis and sinus tract using revascularization technique. Clinical and radiographic examination demonstrated the recovery of vitality, continued root development, and periapical healing at the 7-month follow-up. In addition, severe calcification of the canal was noted at the 36-month follow-up. At the 66-month follow-up, cone-beam computed tomography (CBCT) revealed complete periapical healing, apical closure, increase in root length and thickness of dentin, and severe calcification of the root canal. Even though the nature of tissue within the root canal is unknown, revascularization appears to give good clinical and radiographic success. This case report highlights that severe calcification of the canal is one of the long-term outcomes of revascularized root canals.

Regeneration and Repair in Endodontics-A Special Issue of the Regenerative Endodontics-A New Era in Clinical Endodontics

Caries is the most common cause of pulp-periapical disease. When the pulp tissue involved in caries becomes irreversibly inflamed and progresses to necrosis, the treatment option is root canal therapy because the infected or non-infected necrotic pulp tissue in the root canal system is not accessible to the host's innate and adaptive immune defense mechanisms and antimicrobial agents. Therefore, the infected or non-infected necrotic pulp tissue must be removed from the canal space by pulpectomy. As our knowledge in pulp biology advances, the concept of treatment of pulpal and periapical disease also changes. Endodontists have been looking for biologically based treatment procedures, which could promote regeneration or repair of the dentin-pulp complex destroyed by infection or trauma for several decades. After a long, extensive search in in vitro laboratory and in vivo preclinical animal experiments, the dental stem cells capable of regenerating the dentin-pulp complex were discovered. Consequently, the biological concept of ‘regenerative endodontics’ emerged and has highlighted the paradigm shift in the treatment of immature permanent teeth with necrotic pulps in clinical endodontics. Regenerative endodontics is defined as biologically based procedures designed to physiologically replace damaged tooth structures, including dentin and root structures, as well as the pulp-dentin complex. According to the American Association of Endodontists’ Clinical Considerations for a Regenerative Procedure, the primary goal of the regenerative procedure is the elimination of clinical symptoms and the resolution of apical periodontitis. Thickening of canal walls and continued root maturation is the secondary goal. Therefore, the primary goal of regenerative endodontics and traditional non-surgical root canal therapy is the same. The difference between non-surgical root canal therapy and regenerative endodontic therapy is that the disinfected root canals in the former therapy are filled with biocompatible foreign materials and the root canals in the latter therapy are filled with the host's own vital tissue. The purpose of this article is to review the potential of using regenerative endodontic therapy for human immature and mature permanent teeth with necrotic pulps and/or apical periodontitis, teeth with persistent apical periodontitis after root canal therapy, traumatized teeth with external inflammatory root resorption, and avulsed teeth in terms of elimination of clinical symptoms and resolution of apical periodontitis.

A Successful Endodontic Outcome with Non-Obturated Canals

This case report represents the outcome of endodontic treatment in an infected mandibular molar with periradicular periodontitis and inherent poor prognosis of root canal treatment due to severe root curvature. The tooth was successfully treated by leaving the mesial root non-obturated, the canal orifices were coronally sealed with calcium enriched mixture cement and a definitive coronal amalgam restoration, was placed at the subsequent visit.

Pulp Revascularization on Permanent Teeth with Open Apices in a Middle-aged Patient

Pulp revascularization is a promising procedure for the treatment of adolescents' immature permanent teeth with necrotic pulp and/or apical periodontitis. However, the ability to successfully perform pulp revascularization in a middle-aged patient remains unclear. A 39-year-old woman was referred for treatment of teeth #20 and #29 with necrotic pulp, extensive periapical radiolucencies, and incomplete apices. Pulp revascularization procedures were attempted, including root canal debridement, triple antibiotic paste medication, and platelet-rich plasma transplantation to act as a scaffold. Periapical radiographic and cone-beam computed tomographic examinations were used to review the changes in the apical lesions and root apex configuration. The patient remained asymptomatic throughout the 30-month follow-up. Periapical radiographic examination revealed no change in the apical lesions of either tooth at 8 months. The periapical radiolucency disappeared on tooth #20 and significantly decreased on tooth #29 by the 30-month follow-up, findings that were also confirmed by cone-beam computed tomographic imaging. No evidence of root lengthening or thickening was observed. Successful revascularization was achieved in a middle-aged patient's teeth.