Apically Extruded Sealers: Fate and Influence on Treatment Outcome

Clinical outcome of non-surgical root canal treatment using different sealers and techniques of obturation in 237 patients: A retrospective study

OBJECTIVES

The aim of this retrospective study was to compare the clinical results of two root canal sealers and three obturation techniques used for non-surgical root canal treatment.

MATERIALS AND METHODS

A total of two hundred eighty-three root canal treated teeth in two hundred thirty-seven patients with minimum a 6-month follow-up was included for this study. The canals were filled with three different modes: 1) cold lateral condensation (CLC) and AH Plus Sealer; 2) continuous wave condensation technique (CWC) and AH Plus Sealer, and 3) sealer-based obturation technique (SBO) and AH Plus Bioceramic Sealer. The treatment outcome was analysed based on clinical signs and symptoms, and periapical radiograph (periapical index, PAI).

RESULTS

There were no significant differences in treatment outcome between various sealers and filling techniques applied. The sealer extrusion was found most frequently in the CWC group (60.67%), followed by SBO (59.21%) and CLC (21.19%) with statistically significant differences (p < .05). The initial diagnosis, previous treatment and sealer extrusion (p < .05) were prognostic factors that affected treatment outcome.

CONCLUSIONS

Based on the findings of this study, neither the sealer type nor the filling technique affected the treatment success while preoperative diagnosis, previous treatment and sealer extrusion had significant effect on the outcome.

CLINICAL RELEVANCE

A bioceramic sealant applied along with the single-cone technique might be considered as an alternative method in root canal obturation.

The efficacy of premixed bioceramic sealers versus standard sealers on root canal treatment outcome, extrusion rate and post-obturation pain: A systematic review and meta-analysis

BACKGROUND

Limited evidence is available regarding the superior clinical properties of bioceramic sealers comparted with traditional standard sealers.

OBJECTIVES

This review aimed to answer the following research questions: 'In healthy patients requiring a root canal treatment (P), what is the efficacy of premixed bioceramic sealers (I) compared with traditional root canal epoxy resin-based sealers (C) in terms of survival, success rates (PICO1) sealer extrusion and resorption (PICO2) post-obturation pain (PICO3) (O)?'

METHODS

Authors independently searched three electronic databases: PubMed (including MEDLINE), Web of Science, Embase and Scopus up to 31 October 2023. This was accompanied by both grey literature and manual search. Detailed selection criteria were applied, namely mature permanent teeth requiring root canal treatment, premixed bioceramic sealer with gutta-percha as an intervention group, a standard filling technique as control group and full-text available in English. A random-effect meta-analysis was used to synthesize the body of evidence regarding the use of bioceramic sealers in root canal treatment and their impact on post-obturation pain. Effect sizes were represented as relative risks on a logarithmic scale for binary outcomes and as mean differences for continuous outcomes.

RESULTS

A total of 941 articles were identified. Fifteen Comparative clinical studies were finally included. Eleven were randomized clinical trials, and four were prospective clinical trials with control group. The follow-up of these studies was not greater than 2 years. No publication bias was observed in any study. No significant differences were observed between the two groups in terms of survival and success rates. A small non-significant lower risk of extrusion was observed for bioceramics. A small, non-significantly lower post-operative-pain within 24-h was observed when bioceramics were used.

DISCUSSION

The majority of current evidence shows inconsistencies in reporting and is of short-term duration. Robust prospective long-term trials are needed in this area to better support future recommendations.

CONCLUSION

This systematic review is the first to analyse several clinical outcomes using premixed sealers. Included studies differed in terms of clinical protocol and operator expertise, but reported a similar outcome when comparing bioceramic versus standard sealers. Tooth survival, treatment outcome, post-operative pain and periapical extrusion were similar and presented no significant differences between the two sealer types.

REGISTRATION

PROSPERO database (CRD42023449151).

Characterisation and evaluation of physical properties of AH-Plus sealer with and without the incorporation of petasin, pachymic acid, curcumin and shilajit-an invitro study

BACKGROUND

AH Plus, an epoxy resin-based sealer, is widely used in endodontic practice, owing to its good physical properties that confers longstanding dimensional stability and good adhesion to dentin. Nevertheless, its propensity to trigger inflammation, especially in its freshly mixed state, has been extensively documented. Phytochemicals such as Petasin, Pachymic acid, Curcumin, and Shilajit are known for their anti-inflammatory and analgesic effects. This study aimed to analyze and determine the effect of these natural products on the physical properties of AH Plus sealer when incorporated with the sealer.

METHODS

AH Plus (AHR) sealer was mixed with 10% petasin, 0.75% pachymic, 0.5% and 6%shilajit to obtain AHP, AHA, AHC and AHS in the ratio of 10:1 and 5:1 respectively. Five samples of each material were assessed for setting time, solubility, flow, and dimensional stability in accordance with the ISO 6876:2012 standardization. Sealers were characterized through scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Statistical evaluation involved the Kolmogorov-Smirnov and Shapiro-Wilks tests for normality and the one-way ANOVA test for analysis.

RESULTS

In this investigation, the characterisation analysis revealed a relatively similar microstructure in all the experimental root canal sealers. All experimental groups, excluding the control group, exhibited an increase in flow ranging from 11.9 to 31.4% at a 10:1 ratio. Similarly, for the 5:1 ratio, the increase ranged from 12.02 to 31.83%. In terms of dimensional stability, all groups at the 10:1 ratio showed a decrease compared to the control group. The addition of natural agents to AHR in 10:1 ratio led to a reduction in setting time by 8.9-31.6%, and at a 5:1 ratio, the reduction ranged from 8.1 to 31.5%. However, regarding solubility, the addition of natural agents did not induce any significant alterations.

CONCLUSION

Based on the results of this study, it can be concluded that all tested root canal sealers exhibited properties that met the acceptable criteria outlined in the ISO 6876:2012 standardization.

The Effect of Calcium Hydroxide Pastes on Isolated Vital Nerve Fibers

INTRODUCTION

Calcium hydroxide pastes (CHPs), commonly used for disinfecting root canals during endodontic treatment, are generally considered safe. However, accidental extrusions result in minimal injuries and little to no discomfort, except when extruded pastes come into contact with nerve bundles, such as the inferior alveolar nerve. Currently, there is a lack of information about the possible role of specific paste vehicles on the extent of nerve injury. The purpose of this study was to compare the role that paste vehicles, such as water or methylcellulose, may play when nerve fibers are exposed to CHP.

METHODS

Isolated sciatic nerves of Sprague-Dawley rats were exposed to either water-based or methylcellulose-based CHP for varying durations of time (30, 60, or 90 minutes). Histopathological changes, including axonal edema, myelin alterations, and loss of cellular outlines, were assessed, and the degrees of changes were compared using chi-square intraclass correlation coefficient tests.

RESULTS

Both groups exposed to the pastes demonstrated varying degrees of histopathologic changes, including axonal edema, myelin changes, and loss of cellular outlines, at different exposure times. The water-based calcium hydroxide paste induced these changes more rapidly than the methylcellulose-based paste. Similar patterns were observed in the scanning electron microscopic findings. Exposure time emerged as an important difference in the effects of the 2 pastes. In each of these tests, all observations of water-based paste exposure were rated as moderate to severe, whereas the observed cellular changes (axonal, myelin, and intact cellular outline) were rated as mild to moderate after exposure to methylcellulose-based paste for the same exposure durations. The chi-square tests indicated a statistically significant association between the material and each of the outcomes (axonal changes: χ²15 = 81.0, P < .001; myelin changes: χ²15 = 81.0, P < .001; intact cellular outline, χ²15 = 81.0, P < .001). The intraclass correlation coefficient value was 0.93.

CONCLUSIONS

The study demonstrates that axonal and myelin damage increase with longer exposure times, with water-based CHP causing more damage than methylcellulose-based CHP at each time point.

The Effects of Calcium Silicate- and Calcium Hydroxide-based Root Canal Sealers on Postoperative Pain: A Randomized Clinical Trial

INTRODUCTION

This study aimed to compare the postoperative pain level changes resulting from using calcium silicate- (EndoSeal MTA) and calcium hydroxide-based (Sealapex) root canal sealers in mandibular first and second molar teeth with symptomatic apical periodontitis.

METHODS

A total of 60 patients with symptomatic apical periodontitis in their lower molar teeth were randomly allocated into 2 groups according to sealer type (n = 30). Demographic data, including gender, age, and smoking habit, and preoperative pain measures were recorded. Root canal treatments were performed in a single visit. Postoperative pain measurements and analgesic intake were measured at 6, 12, 24, and 48 hours and after 3, 5, and 7 days using the visual analog scale. The data were statistically analyzed using a chi-squared test (to compare gender, age, smoking habit, analgesic intake, and sealer extrusion), the Mann-Whitney U test (to compare pain levels), Friedman tests (for the evaluations of the reduction in pain levels over time), and Spearman's correlation test (to analyze the relationships of age, gender, smoking habit factors with postoperative pain) (P = .05).

RESULTS

The statistical analysis showed no significant differences between the groups in postoperative pain and analgesic intake at any of the time intervals evaluated (P > .05).

CONCLUSIONS

Patients treated with calcium silicate- and calcium hydroxide-based root canal sealers experienced similar postoperative pain and no statistically significant differences were observed in analgesic intake.

Evaluation of the Impact of Calcium Silicate-Based Sealer Insertion Technique on Root Canal Obturation Quality: A Micro-Computed Tomography Study

BACKGROUND

Calcium silicate-based sealers have gained in popularity over time due to their physicochemical/biological properties and their possible use with single-cone obturation. The single cone technique is a sealer-based obturation and there is still a knowledge gap regarding the potential impact of the sealer insertion method on the root canal-filling quality. Therefore, the aim of this micro-CT study was to assess the impact of the calcium silicate-based sealer insertion technique on void occurrence and on the sealer extrusion following single-cone obturation.

METHODS

Thirty-six single-rooted mandibular premolars with one canal were shaped with Reciproc® R25 (VDW, Munich, Germany) then divided randomly into four groups of nine canals, each depending on the TotalFill® BC Sealer insertion technique used with single cone obturation: injection in the coronal two-thirds (group A); injection in the coronal two-thirds followed by direct sonic activation (group B); injection in the coronal two-thirds followed by indirect ultrasonic activation on tweezers (group C); sealer applied only on the master-cone (control group D). Samples were then scanned using micro-CT for voids and sealer extrusion calculation. Data were statistically analyzed using v.26 IBM; Results: No statistically significant differences were noted between the four groups in terms of voids; nevertheless, sonic activation (group B) followed by ultrasonic activation on the tweezers (group C) showed the best results (p = 0.066). Group D showed significantly less sealer extrusion when compared with group C (p = 0.044), with no statistically significant differences between groups D, A and B (p > 0.05).

CONCLUSIONS

Despite no significant differences observed between the different sealer placement techniques, the use of sonic and ultrasonic activation might be promising to reduce void occurrence. Further investigations are needed to demonstrate the potential benefit of calcium silicate-based sealer activation especially in wide and oval root canals in order to improve the quality of the single-cone obturation.

Effectiveness of root canal filling materials and techniques for treatment of apical periodontitis: A systematic review

BACKGROUND

Apical periodontitis (AP) is an inflammatory disease of the apical periodontium as sequelae of pulp death. It is managed by disinfection and filling of the root canal space.

OBJECTIVES

The aim of this systematic review was to investigate whether obturation techniques and materials used for root canal filling led to the management of AP.

METHODS

A systematic review protocol was written following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist and registered on the international prospective register of systematic reviews (PROSPERO; CRD42021260275) including two populations, interventions, comparisons, outcomes and time (PICOT) for the research questions querying the effectiveness of obturation techniques (PICOT 1) and materials (PICOT 2) for the management of AP. Electronic searches were conducted on PubMed, ScienceDirect, Scopus and Embase search engines. Searches on International Endodontic Journal, Journal of Endodontics, Clinical Oral Investigations, Journal of Dental Research and Journal of Dentistry websites were also conducted, until May 2021. Both primary (tooth survival) and secondary outcomes were evaluated. The risk of bias was assessed by Cochrane RoB2 for the randomized and ROBINS-I for the nonrandomized trials.

RESULTS

The search strategy identified 1652 studies, with 1600 excluded on the title and abstract screening, leaving 52 studies for full-text screening. In total, 10 studies met the inclusion criteria. The obturation technique and materials used did not affect the outcome of AP. Vertical compaction resulted in faster resolution of periapical lesions. The oral health-related quality of life of patients treated with lateral condensation exhibited poorer outcomes compared with single matched cone after 6 months of recall.

DISCUSSION

The inclusion and exclusion criteria used for this systematic review enabled the capture of all the literature available on the effect of obturation techniques and materials on the outcome of AP. The data were heterogenous, and a number of articles investigating obturation techniques had no information on the materials and techniques used as they looked at the quality of fill.

CONCLUSIONS

Included studies did not find any difference between different procedures (PICOT 1) and materials (PICOT 2). The risk of bias was high, thus the findings should be interpreted with caution.

REGISTRATION

PROSPERO registration number: CRD42021260275.

The Effect of Unintentional AH-Plus Sealer Extrusion on Resolution of Apical Periodontitis After Root Canal Treatment and Retreatment-A Retrospective Case-control Study

INTRODUCTION

This study aimed to investigate the effect of unintentional AH Plus sealer extrusion on the outcome of nonsurgical root canal treatment and retreatment in teeth with apical periodontitis (AP) compared to teeth with AP and no sealer extrusion at the 1-year follow-up.

METHODS

In a retrospective case-control study conducted from September 2016 to September 2021, teeth presenting clinical and radiographic signs of AP prior to treatment were included. The study comprised 2 groups: AH Plus sealer extrusion group (n = 60): initial root canal treatment or nonsurgical retreatment with unintentional apical extrusion of AH Plus sealer; and no AH Plus sealer extrusion group (n = 60): underwent the same treatment types without sealer extrusion. Additional factors, including sex, age, tooth type, tooth location, and treatment type, were recorded as potential outcome predictors. At 1-year follow-up, teeth were evaluated clinically and radiographically, and outcomes were classified as favorable (healed/healing) or unfavorable (uncertain/non-healing). Statistical analyses, such as the χ2 test, logistic regression, and Mann-Whitney U test, were employed for data analysis.

RESULTS

A favorable outcome was observed in 88.4% and 85% of the cases of the AH Plus sealer extrusion and no AH Plus sealer extrusion groups, respectively. There was no statistically significant difference between the groups in terms of outcomes (P > .05) when analyzed categorically or ordinally. Of independent variables, nonsurgical retreatment showed lower healing of AP in both groups.

CONCLUSIONS

Unintentional AH Plus sealer extrusion did not affect the healing of AP. However, initial root canal treatment showed better healing of AP than nonsurgical retreatment in the presence of AH Plus sealer extrusion. The analyzed outcome predictors had no effect on treatment outcome.

Influence of sealer type on treatment outcome of teeth with apical periodontitis: a systematic review

BACKGROUND

The purpose of this article was to Evaluate the influence of sealer on the outcome of non-surgical endodontic treatment or retreatment of permanent teeth with apical periodontitis (PROSPERO registration: CRD42020205951).

METHODOLOGY

A systematic review of original clinical studies was carried out following PRISMA guidelines to answer whether the type of sealer used in endodontic treatment or retreatment influences the repair of apical periodontitis determined by clinical and radiographic parameters. Electronic searches were performed in PubMed, Embase, Web of Science, Scopus, and the Cochrane Library database, until May 2023. Gray literature and a hand search of reference lists were also performed. The risk of bias was assessed using Cochrane RoB2 for randomized trials and the Newcastle-Ottawa Scale (NOS) for prospective and retrospective cohort and case-control studies.

RESULTS

Among 1046 studies, a total of 819 were selected by title and abstract, resulting in 23 for full-text review. In total, 11 studies met the inclusion criteria (1467 patients/teeth with apical periodontitis). The quality assessment using RoB2 included five randomized control trials, of which four had medium risk and one had a low risk of bias. According to the NOS scale, five studies were classified as low risk and one study was considered as medium risk of bias. The sealer type and obturation techniques varied, and the mean follow-up time was 3.7 years. Most studies used two-dimensional radiographic criteria to assess the treatment outcome sealers and not cements. Eight studies did not find significant differences when comparing cements. The healing rates ranged from 56.7% to 90%.

CONCLUSIONS

The results of this review support that the current endodontic sealers do not seem to influence the treatment outcome of permanent teeth with apical periodontitis. Although the studies had medium and low risk of bias, the results should be interpreted with caution. More randomized studies of long-term outcomes comparing filling materials are needed to strengthen this claim and allow for a meta-analysis.

Tip and taper compatibility of accessory gutta-percha points with rotary and reciprocating instruments

Objectives

This study was conducted to evaluate and compare the tip and taper compatibility of accessory gutta-percha points (AGPs) with various rotary and reciprocating instruments.

Materials and Methods

Using a profile analyzer, tip and taper measurements were taken of 10 AGPs of each of the 14 models available from Odous de Deus and the 4 models available from Dentsply-Maillefer. Diameter measurements were taken at 1-mm intervals, from 3 mm from the tip (D3) to 16 mm.

Results

Based on the mean values obtained, 3-dimensional (3D) models of the AGPs were drawn in Autodesk Fusion 360 and superimposed on 3D models of each instrument selected (Mtwo, Reciproc, RaCe, K3, and ProDesign Logic) to determine the compatibility between the instrument and the AGP. Data corresponding to the tips and tapers of the various AGPs, as well as the tip and taper differences between the AGPs and the instruments, were analyzed using descriptive statistics. The tapers of the AGPs were subject to the American National Standards Institute/American Dental Association No. 57 standard. The Odous de Deus extra-long medium and extra-long extra-medium AGPs were shown to be compatible with Mtwo, K3, and ProDesign Logic instruments with taper 0.06 and tip sizes 25 and 30, while the Dentsply fine and fine medium cones were compatible with Mtwo, RaCe, and K3 instruments with conicity of 0.04 and tip sizes 35 and 40.

Conclusions

Both the Odous de Deus and Dentsply commercial brands included 2 AGP models with tip (D3) and taper compatibility with Mtwo, RaCe, K3, and/or Prodesign Logic instruments.

Outcome of root canal treatment of teeth with chronic apical periodontitis treated with foraminal enlargement and 2% chlorhexidine gel: a retrospective cohort study

INTRODUCTION

This retrospective cohort study aimed to estimate the success rate (SR) of primary root canal treatment on teeth with a diagnosis of pulp necrosis (PN) and asymptomatic apical periodontitis (AAP) when using 2% chlorhexidine gel as an auxiliary chemical substance (ACS) and foraminal enlargement instrumentation technique.

METHODS

This study evaluated 178 patients with 206 teeth submitted to primary root canal treatment performed by graduate residents in endodontics. The inclusion criteria were patients who underwent treatment over a period of 1 to 7 years on teeth with a diagnosis of PN and AAP. The SR was evaluated clinically and radiographically and categorized considering strict' (complete resolution of periradicular lesion) or 'loose' (reduction in the size of existing periradicular lesion) criteria. Cases of clinical and/or radiographical absence of repair were classified as a failure. Two calibrated examiners independently assessed treatment outcomes using the ImageJ software.

RESULTS

The SR were 81.1% (95% CI: 75.7% - 86.4%) and 87.4% (95% CI: 82.8% - 91.9%) when considering the 'strict' or 'loose' criteria, respectively. Females had a higher SR when strict criteria were applied. Also, the SR was significantly reduced when there was an increase in the patient's age.

CONCLUSION

Within the limitations of this study, it was found that teeth with a diagnosis of PN and AAP and treated associating the use of 2% chlorhexidine gel and foraminal enlargement achieved substantial SR. Gender and age were prognostic factors that played a significant role in the SR. Future randomized controlled trials should further investigate the effects of foraminal enlargement and 2% chlorhexidine gel as an ACS.

Dimensional changes of endodontic sealers-An in vitro model simulating a clinical extrusion scenario during 18 months

OBJECTIVES

To examine the dimensional changes of endodontic sealers during 18 months using three-dimensional (3D) surface scanning and subtraction radiography in a novel in vitro sealer-extrusion model.

MATERIAL AND METHODS

Fifty endodontically instrumented acrylic teeth were randomly allocated to five groups (n = 10) filled with Apexit Plus, AH Plus, BioRoot RCS, TubliSeal EWT, and gutta-percha (control). Freshly mixed sealers were intentionally extruded during obturation. All teeth were immersed in a physiologic solution for up to 18 months. Blinded 3D surface scans (resolution: ~10 μm) and digital radiographs of the teeth were obtained at baseline (immediately after obturation); and then after 1 week, and at 1, 3, and 18 months. For blinded assessment of sealer dimensional change, 3D models and radiographs were superimposed using specific software. Volumetric differences, root mean square (RMS), and area change from subtraction radiography measured at each period within each sealer group were thereafter calculated. Repeated measures analyses were done with Bonferroni adjustment for multiple comparisons; standard errors, p values, and 95% confidence intervals (CI) were reported.

RESULTS

Analyses of the volumetric data confirmed significant, progressive material loss for Apexit Plus when compared to the other investigated sealers or the control group (p ≤ 0.02). Immersion period significantly influenced the volumetric dimensional changes of Apexit Plus already after 1 month (p < 0.01). For TubliSeal EW, the effect of the immersion period on the dimensional changes was noted after immersion for 3 months (p ≤ 0.02), while for BioRoot RCS this was evident only at 18 months (p < 0.01). Same trends were noted for the RMS data, whereas progressive dimensional changes using subtraction radiography only revealed significant changes for Apexit Plus (p = 0.01).

CONCLUSIONS

The largest dimensional changes were shown by Apexit Plus, followed by Tubliseal EWT and BioRoot RCS. AH Plus remained stable throughout 18 months.

The Use of Premixed Calcium Silicate Bioceramic Sealer with Warm Carrier-Based Technique: A 2-Year Study for Patients Treated in a Master Program

Background: Recently several calcium silicate flowable sealers have been introduced as endodontic materials for the root canal. This clinical study tested the use of a new premixed calcium silicate bioceramic sealer in association with the Thermafil warm carrier-based technique (TF). Epoxy-resin-based sealer with the warm carrier-based technique was the control group. Methodology: Healthy consecutive patients (n = 85) requiring 94 root canal treatments were enrolled in this study and assigned to one filling group (Ceraseal-TF n = 47, AH Plus-TF n = 47) in accordance with operator training and best clinical practice. Periapical X-rays were taken preoperatively, after root canal filling and after 6, 12 and 24 months. Two evaluators blindly assessed the periapical index (PAI) and sealer extrusion in the groups (k = 0.90). Healing rate and survival rate were also evaluated. Chi-square tests was used to analyze significant differences between the groups. Multilevel analysis was performed to evaluate the factors associated with healing status. Results: A total of 89 root canal treatments in 82 patients were analyzed at the end-line (24 months). The total drop-out was 3.6% (3 patients; 5 teeth). A total of 91.1% of healed teeth (PAI 1-2) was observed in Ceraseal-TF, with 88.6% in AH Plus-TF. No significant difference was observed on healing outcome and survival among the two filling groups (p > 0.05). Apical extrusion of the sealers occurred in 17 cases (19.0%). Of these, 6 occurred in Ceraseal-TF (13.3%) and 11 in AH Plus-TF (25.0%). Three Ceraseal extrusions were radiographically undetectable after 24 months. All the AH Plus extrusions did not change during the evaluation time. Conclusions: The combined use of the carrier-based technique and premixed CaSi-based bioceramic sealer showed clinical results comparable with carrier-based technique and epoxy-resin-based sealer. The radiographical disappearance of apically extruded Ceraseal is a possible event in the first 24 months.

Factors that affect the outcomes of root canal treatment and retreatment-A reframing of the principles

This paper undertakes a broad and comprehensive synthesis of relevant clinical, biological, biomechanical, technical and healthcare services data to understand the factors affecting outcomes of periapical healing after root canal (re)treatment. The medical and dental evidence-based era (1980-present) is contextualized with the earlier evidence drive in endodontics (1911-1940) triggered by the focal infection era. The current evidence-based approach has a sharper focus on evidence quality and derivation of practice guidelines. Contrary views question whether guideline-driven, or expertise-development-driven endeavours would best serve outcome improvement in society. The endodontic discipline functions in a broad healthcare framework and sustains industrial, economic and trend pressures that may be deemed to influence outcomes. The nature of root canal treatment and the challenges in determining the factors that affect its outcomes is discussed. The factors potentially affecting periapical healing after root canal treatment are classified into pre-operative, intra-operative and postoperative groups. These categories subsume multiple elements with interactive influences, creating a complex picture, further confounded by some apparently surprising, counter-intuitive and contradictory findings. The technical versus biological conundrum in root canal treatment continues to cause cognitive dissonance. However, due reflection and cross-discipline-synthesis resolve the apparent data conflicts into a very simple, consistent and plausible picture of how root canal treatment works and the key factors that affect periapical healing. Root canal retreatment is considered mainly in the context of its differences from primary treatment as the majority of factors influencing outcomes are common to both. The exceptional difference is that retreatments have a proportionately reduced probability of healing by virtue of compromised apical root canal ramification access or modified host/infection interactions. Root canal (re)treatment outcomes are dominantly influenced by the nature of prior dynamic host/infection interaction (pre-operative patient factors) and how the direction of this dynamic is influenced by two factors: (1) the active efficacy of the operators' root canal treatment protocol to sustain a microbial ecological shift (intra-operative treatment factors) and dampen periapical inflammation; and (2) the passive ability of the functional tooth (and its restoration margin) to maintain its integrity to resist infection reversal (postoperative restorative factors).

Comparison of the sealing ability of bioceramic sealer against epoxy resin based sealer: A systematic review & meta-analysis

Objective

This systematic review and meta-analysis aimed to evaluate if bioceramic sealers had superior sealing properties to epoxy resin-based sealers.

Methodology

A systematic search was performed in the following databases: MEDLINE Ovid (from 1946 onwards), Scopus, Google Scholar, EBSCO, and a hand search of references of included articles was also done. In vitro and ex vivo studies were included. Risk of bias was assessed, and quantitative synthesis was performed for microleakage measured using vertical dye penetration, horizontal dye penetration, and dentin-sealer gap. Summary effect was reported as Standardized Mean Difference with 95% CI. Subgroup analysis was performed based on the imaging modalities, the obturation techniques, and the file systems employed.

Results

A total of 24 studies were included. Meta-analysis demonstrated no significant difference between the sealing ability of bioceramic sealer and epoxy resin-based sealer when measured using the microleakage tests [SMD -0.59(95%CI: 1.74,0.55)]. Subgroup analysis revealed no significant differences except when manual K-files were used. Heterogeneity was low when sub-group analysis was done.

Conclusion

Bioceramic sealers and epoxy resin-based sealers both exhibited comparable sealing ability.

Endodontic treatment of the mandibular first molar with six root canals: A case report and literature review

The mandibular first molars normally have three or four root canals and rarely have five or more root canals. The present study reported a rare anatomical configuration with six root canals in the mandibular right first molar diagnosed during endodontic treatment using a dental operating microscope and confirmed with the help of cone-beam computed tomography (CBCT) images. The present case report revealed that there is an increasing possibility of detecting additional canals through the magnification of the microscope and the improvement of CBCT diagnostic technology. As more abnormal morphologies in root canals are reported, dentists need to understand this diversity in anatomical structure and improve treatment techniques.

Influence of Apical Diameter on Filling Material Extrusion during Retreatment - A Micro-CT and CBCT evaluation

AIM

To investigate whether foraminal widening performed at primary treatment has an effect on the amount of apically extruded obturator material during retreatment and to evaluate the sensitivity of cone beam computed tomography (CBCT) in detecting extruded obturator material.

METHODS

Forty palatal roots of maxillary molars were selected based on micro-CT and divided into two groups (n=20): with foraminal widening (WE) and without foraminal widening (NE). To standardize the apical foramen, all specimens were instrumented to the foramen using the Protaper Next system, up to instrument X3. The WE group was instrumented to the foramen up to instrument X5, and the NE group was instrumented 1 mm lower. The canals were obturated 1 mm below the apical foramen with gutta-percha and AH Plus and stored for 7 days at 37 °C and 95% humidity. Roots were fixed in microtubes filled with 1.5% agar gel. The obturation material was removed with Reciproc R50. Scans of the teeth and agar were performed using micro-CT and CBCT. Comparison between groups and between methods was performed using Mann-Withney test (p ≤0.05).

RESULTS

No statistical difference was found when comparing the extruded material between groups using micro-CT (p = 0.589) or CBCT (p = 0.953). CBCT measured a greater volume of extruded material than micro- CT (p = 0.0004).

CONCLUSION

Foraminal widening had no effect on the extrusion of filling material during retreatment. The CBCT favored the evaluation of apically extruded filling material.

Do resin-based sealers increase post-operative pain following root-canal treatment?

Design Systematic review. Case selection This systematic review had a focused and structured research question in term of PICO (Population, Intervention, Comparison and Outcomes). Patients included within the study were those with undergoing primary root canal treatment on a permanent tooth. The intervention was obturation with gutta percha and a resin-based sealer in comparison to obturation with gutta percha and another sealer type. The primary outcome being measured was post-operative pain incidence and/or intensity. An additional, secondary outcome, aimed to assess analgesic intake following treatment.Data analysis Data analysis was carried out by two independent reviewers using a specifically designed template which gave a concise summary of the study included within the review. The form allowed the following details to be recorded: whether a single operator completed treatment; pulpal status; irrigants used; sealer placement technique and type; obturation technique and quality; evaluation time; and outcome measures. An assessment was carried out of each study to ascertain the risk of bias which was categorised as low risk, having some areas of concerns or high risk.Six studies were included within the quantitative analysis which involved analysis of post-operative pain experiences at specified intervals. Qualitative data analysis was completed using a digital software package which allowed comparable results to be combined.Results The results from this systematic review demonstrated no significant difference in post-operative pain incidence between endodontic treatment using resin or non-resin sealers. While seven of the studies had high risk of overall bias, four were deemed low risk, and the majority of studies confirmed that there was no significant difference in the intensity of pain between the two groups. This review also confirmed that analgesic intake is not increased in patients where resin-based sealers are used when compared to non-resin sealers.Conclusion There is no significant difference in post-operative pain when resin-based root canal sealers are used when compared to other root canal sealers. For both resin and non-resin sealers, analgesics use, pain incidence post-operatively and intensity of pain reduce after 24 hours.

Clinical outcome of bioceramic sealer iRoot SP extrusion in root canal treatment: a retrospective analysis

Background

During the obturation procedure, sealer extrusion occurs in some cases. iRoot SP is a kind of bioceramic sealer with superior physicochemical and biological properties. This article reports the outcome of iRoot SP extrusion in root canal treatment and the potential factors associated with the outcome.

Methods

Ninety-nine patients and one hundred and eighty-five teeth treated between 2014 and 2020 were included in this retrospective study. All of the cases were filled with a single-cone technique and the iRoot SP sealer. The minimum follow-up visit period was 1 year. The outcome was evaluated by clinical examination and radiographic examination at recall and was classified as healed, healing (success), or not healed (failure).

Results

The overall success rate of all teeth was 96.8%. The success rate of adequately filled teeth was 97.3%, while that of iRoot SP extrusion was 95.8%; the difference was not statistically significant. Factors such as gender, age, tooth position, follow-up visit period, size of periapical lesion, treatment type and extruding sealer amount had no influence on the outcome of iRoot SP extruded teeth.

Conclusions

The results suggested that iRoot SP extrusion has no adverse effect on the outcome of root canal treatment, which may contribute to the endodontic treatment.

Laboratory study of tissue repair of resin-based endodontic sealers in critical surgical defects

Filling materials should be restricted to the root canal space. However, sometimes it is impossible to control the apical extrusion, in this case, the fate of the filling material and the result of the treatment will depend on its physicochemical properties and biocompatibility.

Pilot Evaluation of Sealer-Based Root Canal Obturation Using Epoxy-Resin-Based and Calcium-Silicate-Based Sealers: A Randomized Clinical Trial

The purpose of this randomized controlled clinical trial was to assess the short-term clinical effectiveness of sealer-based root canal obturation using calcium-silicate-based sealer (CSBS) and epoxy-resin-based sealer (ERBS). A total of eighty patients (eighty teeth) were enrolled and seventy-two patients (seventy-two teeth) were randomly assigned into four different sealer groups: AH Plus (AH, Dentsply Sirona), ADseal (AD, Meta Biomed), CeraSeal (CS, Meta Biomed), or EndoSeal TCS (ES, Maruchi). At the first visit, root canal treatment was performed using ProTaper. Next, the NiTi file system and passive ultrasonic irritation was applied with 2.5% NaOCl. At the second visit, the teeth were obturated with a sealer-based obturation technique using the assigned sealer. The quality of filling obturation was evaluated with postoperative radiographs in terms of the presence of voids and sealer extrusion. The patients were recalled at 1-week, 1-month, and 3-month intervals, and pain levels were measured using visual analog scales (VAS), and clinical examination performed with percussion and palpation. Radiographs were also taken. The results were statistically compared by using the χ2 test or Fisher exact test. Among the 80 teeth included, 72 teeth received allocated intervention and 71 teeth were included in the analysis (98.6% recall). There was no significant difference among the sealers in void and sealer extrusion (p > 0.05). Postoperative pain was not indicated prominently regardless of the type of sealer. For a 3-month follow-up period, all cases were maintained successfully except for one case from AD. According to the findings, there was no significant difference between CSBS and ERBS in terms of postoperative pain or the healing process, and the variation in filling quality appears to be linked to the properties of each product.

Periapical Healing following Root Canal Treatment Using Different Endodontic Sealers: A Systematic Review

The healing of the periapical tissues is crucial to the success of root canal treatment. The review studies effectively examine various endodontic root canal sealants in terms of periapical healing. This systematic review was formulated following the PRISMA 2020 guidelines and registered in the international prospective register of systematic reviews (PROSPERO) number-CRD42021239192. To find relevant articles, PubMed Central and Medline databases (until February 2022) were searched. Studies that evaluated healing following the application of different endodontic sealers were analysed. A primary outcome measure was the resolution of periapical lesions following the endodontic treatment. In vivo studies comparing radiographic treatment outcomes and articles with a minimum of 6-month follow-up were included. A total of 9 clinical trial studies that met all the inclusion criteria were included in the analysis. The overall risk of bias was high in four studies out of nine studies. Periapical lesions showed significant healing after endodontic treatment regardless of sealer type, although bioceramic and bioactive sealers had shown better results.

Physicochemical properties and osteoclastogenesis for three premixed calcium silicate-based sealers post set

Solubility, pH, ion release, cytotoxicity, and osteoclastogenesis inhibition in bone marrow-derived monocyte macrophages (BMMs) were evaluated in EndoSequence BC Sealer (END), Bio-C Sealer (BC), and Sealer Plus BC (SPBC). pH was determined after immersion of the sealers in deionized water (DW) and Minimum Essential Medium Alpha (α-MEM). Solubility was obtained by mass loss. Ion release was measured by using X-ray fluorescence spectroscopy (XRF). Cytotoxicity was evaluated by MTT assay. Inhibition of osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase (TRAP). Data were analyzed using the t-test, ANOVA and Tukey/Dunnett's post-hoc tests (α = 0.05). END had the highest pH in DW (p < 0.05), and BC, in α-MEM (p < 0.05). Solubility in DW was the lowest for SPBC (p < 0.005). The highest calcium release was observed for BC in DW at 12 h (p < 0.05), and in α-MEM at 12 and 24 h (p < 0.05). The lowest toxicity was detected for END (p < 0.05). BC had the highest inhibitory effect on osteoclasts (p < 0.05). Overall, the highest solubility and pH values were found in DW. However, the calcium silicate-based sealer showed higher solubility than the ISO standards. Calcium release was the highest for BC. END showed the highest cell viability, and BC, the highest osteoclast inhibition.

The evaluation of cytotoxicity and cytokine IL-6 production of root canal sealers with and without the incorporation of simvastatin: an invitro study

Background

Freshly mixed root canal sealers when proximate the periapical tissues, trigger varying degrees of cytotoxicity/inflammatory reactions. Simvastatin, a class of the drug statin, is a widely used cholesterol-lowering agent with additional anti-inflammatory activities. This study assessed the effects of simvastatin on cytotoxicity and the release of IL-6 (Interleukin-6) production when incorporated in zinc oxide eugenol and methacrylate resin-based sealers.

Methods

Experimental groups consisted of conventional zinc oxide eugenol and methacrylate based-EndoREZ sealers (ZE & ER respectively) and 0.5 mg/mL simvastatin incorporated sealers (ZES & ERS). L929 mouse fibroblast cells were exposed to freshly mixed experimental sealers and evaluated for cytotoxicity (MTT assay) and inflammation levels (inflammatory marker IL-6 for ELISA) at various time intervals (0h, 24h and 7th day). The values were compared to the cell control (CC; L929 cells alone) and solvent control (SC; L929 cells + DMSO) groups. All the experiments were conducted in triplicates and subjected to statistical analysis using IBM SPSS Statistics software. Non parametric tests were conducted using Kruskal-Wallis and Friedman tests for inter-group and intra-group comparisons respectively. Pairwise comparison was conducted by post hoc Dunn test followed by Bonferroni correction. P values < 0.05 were considered statistically significant.

Results

All the experimental groups (ZE, ER, ZES, ERS) exhibited varying degree of cytotoxicity and IL-6 expression compared to the control groups CC and SC. The cell viability for ZE and ER decreased on day 7 as compared to 24 h. ZES and ERS had higher viable cells (75.93% & 79.90%) compared to ZE and ER (54.39% & 57.84%) at all time periods. Increased expression of IL-6 was observed in ZE & ER (25.49 pg/mL & 23.14 pg/mL) when compared to simvastatin incorporated ZE & ER (ZES-12.70 pg/mL & ERS-14.68 pg/mL) at all time periods. Highest level of cytotoxicity and inflammation was observed in ZE compared to all the other groups on day 7.

Conclusions

Addition of 0.5 mg/mL of simvastatin to the sealers (ZES and ERS) decreased the cytotoxicity in the freshly mixed state and reduces their inflammatory effect.

Obturation of Root Canals By Vertical Condensation of Gutta-Percha – Benefits and Pitfalls

Vertical condensation of gutta-percha is one of the frequently used techniques of hermetic and three-dimensional obturation of root canal system which is one of the primary goals of endodontic tooth treatment. Techniques for filling root canals have been described since ancient Egypt and have undergone dynamic development in recent decades. The aim of the article is to analyze the technique of obturation of root canals using vertical condensation of guttapercha and to point out its benefits and pitfalls.

The poor-quality treatment of the tooth deteriorates its prognosis, function, and long-term survival in the oral cavity; thus, the hermetic obturation of the root canals is one of the most important pillars of the complex tooth treatment. Obturation of the root canals by vertical condensation of warm gutta-percha is nowadays considered in the correct indications as one of the most commonly used techniques in the excellent dental practices. Even though it is quite technologically challenging and time-consuming it enables to reach high level of predictability and clinical success. Currently, the obturation technique based on master gutta-percha cone combined with the calcium-silicate based sealer is emerging. However, long term results of clinical studies and follow-up are needed to make a significant improvement in the area of endodontics.

Influence of Commonly Used Endodontic Irrigants on the Setting Time and Metal Composition of Various Base Endodontic Sealers

The present study aimed to evaluate if commonly used endodontic irrigants such as 3% sodium hypochlorite (NaOCl, Prime Dental, Thane, India), 2% chlorhexidine (CHX, Sigma-Aldrich Co., St. Louis, MO, USA), and 17% ethylenediaminetetraacetic acid (EDTA, Meta-Biomed Co. Ltd., Cheongju-si, South Korea) influenced the setting time and metal composition of different base endodontic sealers on exposure. AH Plus (Dentsply De Trey GmbH, Konstanz, Germany), Sealapex (SybronEndo, Orange, CA, USA), mineral trioxide aggregate (MTA) Fillapex (Angelus Soluções Odontológicas, Londrina, Brazil), and Tubli-Seal (Kerr Dental, Orange, CA, USA) were selected as the different base representatives of endodontic sealers. These sealers were exposed to 3% NaOCl, 2% CHX, and 17% EDTA, and the individual setting time of the sealers was analyzed. The samples were analyzed for heavy metal elements such as chromium (Cr), nickel (Ni), cobalt (Co), cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), and beryllium (Be) by using inductively coupled plasma mass spectrometry (ICP-MS) analysis. For statistical analysis, one-way ANOVA and post hoc Tukey’s tests were used. All selected sealers showed variation in setting time post-exposure to different irrigants. MTA Fillapex had the shortest mean setting time (215.7 min, post-exposure at 187.3 min) (p < 0.05). Mean setting time was also affected for AH Plus (479.6 min, post-exposure at 423.9 min) (p < 0.05) and Tubli-Seal (514.7 min, post-exposure at 465.2 min) (p < 0.05). Sealapex showed the maximum reduction of setting time (864.8 min, post-exposure at 673.4 min) (p < 0.05). All tested sealers showed heavy metals (Cr, Ni, Co, Cd, As, Hg, and Pb) in their composition, and the quantities were influenced by interaction with different irrigants. The heavy metal Be was not seen in any of the samples. Sealapex showed the longest setting time in comparison to other test sealers. Heavy metals were most present in Sealapex, followed by AH Plus, Tubli-Seal, and MTA Fillapex. MTA Fillapex was seen to have the shortest setting time, and heavy metal composition was least affected on interaction with different commonly used endodontic irrigants. Further, this study provides significant insight into the influence of different endodontic irrigants on interaction with different base endodontic sealers, which has not been reported previously, and future studies should emphasize endodontic irrigant-sealer interactions and their possible effects in the long run.

An in vitro study on the effects of serum proteins on Enterococcus faecalis adhesion to three types of root sealers and gutta-percha

BACKGROUND

The extrusion of overfilled materials that extend beyond the apical foramina into the periradicular tissue may serve as a reservoir for bacterial adhesion and further affect recovery from periapical diseases. The aim of this study was to evaluate the effects of serum proteins on Enterococcus faecalis adhesion and survival on the surface of a calcium hydroxide-based root canal sealer (Apexit Plus), an epoxy resin sealer (AH-Plus) and a bioceramic sealer (iRoot SP).

METHODS

Apexit Plus, AH-Plus and iRoot SP were evenly coated on gutta-percha, using gutta-percha alone as the control. After root canal sealer setting, the number of E. faecalis adhering to the root canal sealers and gutta-percha was counted in fetal bovine serum (FBS) or tryptic soy broth supplemented with 1% glucose (TSBG) by viable cell plate counts. The morphology of 7-day-old E. faecalis biofilms in FSB and TSBG was observed by scanning electron microscopy (SEM). Furthermore, E. faecalis biofilms on the three root canal sealers were labeled with a LIVE/DEAD BacLight™ Bacterial Viability Kit, and the ratios of viable to dead cells were analyzed using laser scanning microscopy operative software (Zen software).

RESULTS

In the assays, after 1 and 7 days, the number of E. faecalis adhering to the root canal sealers or gutta-percha in FBS were significantly lower than those in TSBG (P < 0.05). In FBS, E. faecalis adhesion to iRoot SP and gutta-percha was reduced to a greater extent than that adhered to Apexit Plus and AH-Plus. Few E. faecalis accumulated on iRoot SP in FBS, whereas many bacteria assembled on iRoot SP and formed biofilms in TSBG. The ratio of viable cells in the E. faecalis biofilm on iRoot SP was the lowest.

CONCLUSIONS

Calcium hydroxide-based root canal sealers, epoxy resin sealers and bioceramic sealers may provide a substrate for E. faecalis adhesion, and the bioceramic sealer in this study showed the least E. faecalis adhesion in the presence of serum proteins compared to the other two sealers.

The influence of different NiTi instrumentation techniques on postoperative pain after single-visit root canal treatment

This study aimed to evaluate the effect of multi-file rotary (Protaper Universal) and reciprocating single-file (Reciproc Blue) root canal preparation techniques on the occurrence of postoperative pain in asymptomatic mandibular molar teeth with large periapical lesions in single-visit root canal treatment (RCT). A hundred and twenty teeth were randomly assigned to two groups: Protaper Universal (PTU) or Reciproc Blue (RB) instruments. Postoperative pain at 6, 12, 24, 48, 72 h and 7 days after obturation was measured. Mann-Whitney U-test was performed to compare the pain scores between the groups and to assess the relation of pain with patients' age and gender. Spearman's rank correlation was utilized to correlate the pain intensity and analgesic intake at different time points. There was no significant difference between the instrumentation techniques regarding postoperative pain at any time points evaluated (P > 0.05). There was a correlation between analgesic intake and intensity of pain (P < 0.05). No statistically significant difference was found among the groups assessed in the study in terms of analgesic intake (P > 0.05).

The Structural, Physical, and In Vitro Biological Performance of Freshly Mixed and Set Endodontic Sealers

Objective:

The objective of this study was to evaluate the in vitro performance of endodontic sealers in their freshly mixed and set forms.

Methods:

The commercially used endodontic sealers (AH Plus, Dia-ProSeal, GuttaFlow 2, and Pulpdent Root Canal Sealer) were investigated and the chemical structure of freshly mixed and set sealers were assessed with Fourier transform infrared spectroscopy (FTIR). The surface morphology and elemental analysis were assessed with a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy. The pH and solubility analysis were performed and the cytotoxicity was done on extracts of freshly mixed and set materials using Alamar blue assay. One way ANOVA and Post Hoc Tukey analysis was used to do multiple comparison analysis of the mean values and standard deviation results through SPSS version 20 (IBM Software, NY, USA) for pH, solubility, and cytotoxicity analysis.

Results:

FTIR analysis revealed the structural pattern and the difference in freshly mixed and set samples was observed with the change in intensities of the peaks. The morphological pattern revealed the presence of micro/nano-particles with pores distributed throughout their structure. The sealer with the least solubility was AH Plus (0.10±0.01) followed by Dia-ProSeal (0.77±0.25), GuttaFlow 2 (1.88±0.82) and Pulpdent Root Canal Sealer (3.03±0.18). The solubility of AH plus was significantly lower (P<0.05) in comparison to GuttaFlow 2 and Pulpdent Root Canal Sealer. The highest pH (10.09±0.034) in the freshly mixed state and highest cytotoxicity in the freshly mixed (70.08±5.852) and set sealers (83.87±5.409) (P<0.05) at day 7 was observed in Dia-ProSeal. GuttaFlow 2 was the most biocompatible sealer in the set state and AH Plus was the most biocompatible sealer in the freshly mixed state at day 7.

Conclusion:

Clinically, the sealer is applied in fresh state, whereby this study signifies that which material is more biocompatible in fresh state and provides insight information to clinicians. AH Plus showed least solubility and cytocompatibility in fresh state compared to other groups.

Comparing the incidence of postoperative pain after root canal filling with warm vertical obturation with resin-based sealer and sealer-based obturation with calcium silicate-based sealer: a prospective clinical trial

OBJECTIVE

This prospective clinical study compares postoperative pain after single-visit, non-surgical root canal treatment of teeth with irreversible pulpitis using two different root canal filling techniques.

MATERIAL AND METHODS

All cases were treated by endodontic residents with a standardized protocol (minimum apical size 35) and filled with one of the two techniques: warm vertical compaction technique (WVT) with gutta percha and epoxy resin-based sealer (AH Plus Jet Root Canal Sealer, Dentsply Maillefer, York, PA, USA) or sealer-based filling technique (SBT) with single cone gutta percha and calcium silicate-based sealer (EndoSequence BC Sealer, Brasseler, Savannah, GA, USA). Surveys were given to participating patients to record pain intensity on a numeric rating scale (NRS, 0-10) at 4, 24, and 48 h postoperatively. Statistical significance was set at 0.05 level.

RESULTS

One hundred ninety-four surveys were distributed over eighteen months. Ninety-two patients returned the survey (41 WVT and 51 SBT), of which 38% were asymptomatic irreversible pulpitis cases. The NRS values reduced over time for both techniques. No statistical difference was found between the two groups at the three time points assessed (p > 0.05). Postoperative pain was related to age, gender, presence of preoperative pain, and sealer extrusion (p < 0.05), however not related to preoperative periapical symptoms (percussion/palpation), dental arch, root type, and experience of the provider (p > 0.05).

CONCLUSIONS

The intensity of postoperative pain for the two obturation techniques was equivalent at evaluated time points.

CLINICAL RELEVANCE

The obturation technique does not influence postoperative pain. After endodontic treatment of symptomatic irreversible pulpitis teeth, the pain subsides in 48 h regardless of the technique.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT04462731.

Microscopic evaluation of sealer penetration and interfacial adaptation of three different endodontic sealers: An in vitro study

Background:

The dentinal tubular penetration depth and interfacial adaptation of sealer are important factors for successful root canal treatment.

Aims:

This study aims to assess and evaluate the sealer penetration depth and interfacial adaptation of AH Plus, Apexit Plus, and GuttaFlow Bioseal sealer to root dentin.

Materials and Methods:

After decoronating sixty extracted single-rooted premolar teeth, preparation was done using ProTaper Gold rotary files until F3. The samples were randomly divided into three groups (n = 20 each) consistent with the sort of sealer used for obturation. After obturation with lateral compaction technique, half of the samples (n = 10 each) were sectioned transversely for measuring tubular depth penetration under a confocal laser scanning microscope. Longitudinal sections were obtained for the rest half the samples to gauge the difference of sealer using the scanning electron microscope.

Statistical Analysis Used:

Data were analyzed using one-way analysis of variance and Tukey's post hoc tests.

Results:

GuttaFlow Bioseal has shown a significantly higher depth of sealer penetration and minimum interfacial adaptation than resin-based sealer and calcium hydroxide-based sealer (P < 0.05).

Conclusion:

At all root regions, the GuttaFlow Bioseal sealer exhibited more sealer penetration and minimum interfacial adaptation whereas the Apexit Plus sealer exhibited less sealer penetration and maximum interfacial adaptation.

Effect of Endodontic Sealer in Young Molars Treated by Undergraduate Students - A Randomized Clinical Trial

The progression of caries in permanent molar teeth of young patients, frequently result in endodontic treatment. This randomized blinded clinical trial assessed the effect of two endodontic sealers (Sealer 26 and AH Plus) on the incidence of pain and apical repair after endodontic treatment of young molar teeth, and secondly identify factors associated with the outcomes. Endodontic treatment was performed by undergraduate students in molar teeth (n=69) of young patients (n=54) at the Endodontic and Restorative Public Extension Clinic Service. Protaper Next was used and the endodontic sealers were allocated which were restored with direct composite resin. Two primary clinical outcomes - apical repair and postoperative pain, were assessed after 12 and 24 months for blinded operators. Description of incidence rates and mixed-model regression using Generalized Estimation Equations (GEE). After 2 years 69 molar teeth of 54 patients were evaluated. No effect of the endodontic sealer was observed irrespective of period of evaluation. Apical repair incidences and asymptomatic teeth were, respectively, 90.5 and 89.3, 96.8 and 90.0% during 1 and 2 years of follow-up. Failed apical repair was associated with unsatisfactory pulpectomy (p=0.003) and periapical conditions (p=0.007) as well as their interaction (p=0.016). None of these independent variables was able to predict the occurrence of pain in both periods. Prognosis of apical repair is dependent on the initial conditions. Endodontic treatment of young molars associated with composite resin restorations performed by undergraduate students have satisfactory results after 2 years and was effective to prevent the risk of permanent teeth loss.

The effect of two different irrigation needles on post-operative pain after pulpectomy in primary molar teeth: A randomized clinical study

BACKGROUND

Post-operative pain (PP) following pulpectomy is of concern for endodontic patients and dentists.

AIM

This study evaluated the intensity of PP following pulpectomy in primary maxillary molars, using two irrigation needles.

DESIGN

One hundred patients in ages ranging from 6-9 years requiring pulpectomy for asymptomatic primary teeth with non-vital pulp were included in the study. The participants were randomly assigned to two groups of 50 patients each, according to the type of irrigation needle used, that is, a conventional open-ended needle and a double side-vented needle. The teeth were obturated and then permanently restored. The presence of PP was assessed after six, 12, 24, 48, and 72 hours, and finally after one week, using a four-point pain intensity scale. The PP scores were then statistically analysed.

RESULTS

In 6, 12, and 24 hours time intervals, patients who had their teeth irrigated with the open-ended needle exhibited more intense PP than those who had their teeth irrigated with a double side-vented needle (P < .05). After 48 hours, 72 hours, and 1 week, however there was no significant difference between the groups (P > .05).

CONCLUSIONS

Side-vented needles may be preferred in order to decrease PP at the first 24 hours after pulpectomy in primary molars.

Physical Properties and Biofunctionalities of Bioactive Root Canal Sealers In Vitro

Calcium silicate-based bioactive glass has received significant attention for use in various biomedical applications due to its excellent bioactivity and biocompatibility. However, the bioactivity of calcium silicate nanoparticle-incorporated bioactive dental sealer is not much explored. Herein, three commercially available bioactive root canal sealers (Endoseal MTA (EDS), Well-Root ST (WST), and Nishika Canal Sealer BG (NBG)) were compared with a resin-based control sealer (AH Plus (AHP)) in terms of physical, chemical, and biological properties. EDS and NBG showed 200 to 400 nm and 100 to 200 nm nanoparticle incorporation in the SEM image, respectively, and WST and NBG showed mineral deposition in Hank's balanced salt solution after 28 days. The flowability and film thickness of all products met the ISO 3107 standard. Water contact angle, linear dimensional changes, and calcium and silicate ion release were significantly different among groups. All bioactive root canal sealers released calcium ions, while NBG released ~10 times more silicon ions than the other bioactive root canal sealers. Under the cytocompatible extraction range, NBG showed prominent cytocompatibility, osteogenecity, and angiogenecity compared to other sealers in vitro. These results indicate that calcium silicate nanoparticle incorporation in dental sealers could be a potential strategy for dental periapical tissue regeneration.

Postoperative pain after root canal filling with different endodontic sealers: a randomized clinical trial

The aim of this randomized clinical trial was to compare the occurrence and intensity of postoperative pain and analgesic intake after root canal treatment, using different root canal sealers. Sixty single-rooted teeth diagnosed with asymptomatic necrosis and apical periodontitis were randomly assigned to 3 experimental groups (n=20), according to the root canal sealer: AH Plus, Endofill or MTA Fillapex. Endodontic treatment was performed in two sessions, and calcium hydroxide was used as the intracanal dressing. Patients were instructed to record pain intensity as none, slight, moderate and severe. Scores from 1 to 4 were attributed to each level of pain after 24 h, 48 h and 7 days. The need for analgesic intake was also recorded. Differences in the incidence of postoperative pain and the need for an analgesic were analyzed using the chi-square test. Differences in pain intensity after treatment were analyzed using the ordinal (linear) chi-square test. No significant differences were detected among the groups in terms of either incidence or intensity of postoperative pain, or need for analgesic intake, at any timepoint (p>0.05). No pain was reported after 7 days. AH Plus, Endofill and MTA Fillapex used for filling root canals resulted in the same rate of postoperative pain and need for analgesic medication.

Secondary Root Canal Treatment with Reciproc Blue and K-File: Radiographic and ESEM-EDX Analysis of Dentin and Root Canal Filling Remnants

Secondary root canal treatment requires the complete removal of filling materials with different chemical-physical properties. A newly developed single-use NiTi instrument (Reciproc Blue, RB) may be more effective in root canal retreatment. The aim of the present study was to evaluate morphology and composition of remnants after retreatment with RB compared to traditional K-File technique, in canals obturated with Thermafil/AH Plus. Twenty-four single-rooted human teeth were shaped with NiTi obturated with AH-Plus/Thermafil and retreated using RB NiTi instruments or manual K-Files. Radiographs were taken to evaluate endodontic space and radiopacity of residual filling-material before/after procedures. After retreatment, samples were longitudinally split and observed by environmental scanning electron microscopy connected to energy dispersive X-Ray spectroscopy (ESEM-EDX) to analyze the debris/remnant position, microchemistry, and dentinal surface morphology. Time for retreatments was recorded and compared using one-way ANOVA (p-value = 0.05). Radiopaque filling residuals were found in both groups. RB system resulted statistically faster than manual K-File in retreatment procedure (p < 0.001). Root canal space radiographic appearance obtained after retreatment with RB was wider than K-File (p < 0.05). ESEM-EDX revealed 4 different morphological dentin area. Area-1: debris-free with typical Ca, P, and N composition of dentin and detected in 70% of the surface. Area-2: presence of deproteinized smear layer free from N and debris in 15% of the surface. Area-3: a thick packed smear layer N-free and with fine debris consisting of trace elements from sealer in 10% of the surface. Area-4: packed with debris and trace elements. No difference was observed between both instruments regarding root canal space appearance and ESEM-EDX analysis. Both systems were able to remove filling material but created a dentine morphology composed of packed debris and filling materials embedded into the smear layer. Dentin surface composition resulted in collagen depleted by irrigation procedures. The reciprocating system required less time to complete retreatment.

The effect of smear layer on bacterial penetration through roots obturated using zinc oxide eugenol-based sealer

BACKGROUND

Smear layer removal has been shown to reduce bacterial penetration through root canal obturations when resin-based endodontic sealer is used. The purpose of this in vitro study was to test this effect when a non-resin-based sealer is used.

MATERIAL AND METHODS

Thirty root segments were assigned to the following groups: Smear layer removed (n = 8); smear layer retained (n = 8); negative controls (n = 10; 5 with smear layer, 5 without); and positive controls (n = 4; 2 with smear layer, 2 without). After rotary instrumentation, smear layers were removed in the treatment group and half of controls using 17% ethylenediamenetetraacetic acid (EDTA) prior to obturation. Each obturated root was affixed into a dual-chamber leakage model employing Streptococcus mutans. Roots were incubated at 37 °C for 120 d. Days until lower chamber turbidity occurred was recorded for each sample, and data were analyzed using Kaplan-Meier survival curve analysis (p = 0.05).

RESULTS

No negative controls leaked, while all positive controls were turbid within 1 day. Mean days to leakage for roots with smear layer intact was 82.75 (+/- 33.29, 95% CI), although three never leaked. Mean days to leakage through roots with smear layer removed was 46.25 (+/- 26.67, 95% CI), and all leaked. Treatment survival curves were significantly different (p = 0.048).

CONCLUSIONS

Under the conditions and limitations of this study, retaining the smear layer reduced the rate of bacterial penetration through canals which had been obturated using zinc oxide eugenol (ZOE) -based sealer.

Determining the Effects of Eugenol on the Bond Strength of Resin-Based Restorative Materials to Dentin: A Meta-Analysis of the Literature

The aim of this study was to determine whether the residual presence of eugenol in coronal dentin may compromise the bond strength of resin-based restorative materials. A search was performed on MEDLINE/Pubmed, Scopus, and by hand search for relevant papers. No restriction was applied for language and publication date. The studies selected for analysis tested specimens with reduced size (micro-shear bond strength (µSBS) and micro-tensile bond strength (µTBS)) of adhesive systems and resin-based restorative materials applied to coronary dentin “contaminated” with eugenol-based materials. The search provided 335 articles, but only 10 studies met the inclusion criteria. The pooled global analysis showed a significant influence of eugenol, as it negatively influenced the bond strength of resin-based restorations (5.79 (3.31–8.28) MPa, p < 0.00001). The subgroup analyses for conventional etch-and-rinse (p = 0.003) and self-etch (p < 0.0004) adhesive systems, as well as for µSBS (p = 0.01) and µTBS (p < 0.0001), showed a negative influence of eugenol on the bond strength. Data were statistically heterogeneous. However, it was possible to observe that eugenol could negatively affect the bonding of resin-based restorative materials to dentin. Further evidence is necessary in order to acquire more accurate information about this issue and confirm that the residual presence of eugenol in dentin compromises the bond strength of resin-based materials.

Current Trends in Practice of Residents in the Saudi Board of Endodontics Program

Objectives The purpose of the current study was to collect information about some techniques and armamentarium currently used by the Saudi Board of Endodontics residents in relation to the technical steps of root canal therapy.

Materials and Methods A web-based survey was sent to the Saudi Board of Endodontics residents, based in the western area of Saudi Arabia. The survey assessed controversial concepts, and collected information regarding new instruments and materials, used in the technical steps of nonsurgical root canal treatment. A one-sample chi-square test, with a 95% level of significance, was applied to determine whether there were significant differences between respondents’ answers.

Results A total of 45 out of 50 residents (90%) responded to the questionnaire. The majority of Saudi Board residents of Endodontics, who participated in this survey, used the mean of working length (ML) measured by periapical X-Ray and apex locator in the presence of a radiographic lesion (63.3%), and maintained apical patency in all cases (80.0%). ProTaper Universal (40%) and ProTaper Next (41.2%) were the most common NiTi rotary systems used for root canal instrumentation. Thirty percent of respondents used adjunct device with irrigation, and 80% advocated smear layer removal. Zinc oxide–eugenol-based sealers were the most common used sealers (70%), and most residents (86.6%) did not advocate sealer extrusion.

Conclusions This study revealed that residents of the Saudi Board of Endodontics program adopt new endodontic technologies. There is, however, a need for more investigations regarding this objective, including responses from all residents in Saudi Arabia.

Assessment of Extrusion and Postoperative Pain of a Bioceramic and Resin-Based Root Canal Sealer

Objectives  The objective of this study was to compare a bioceramic and a resin-based endodontic sealer with regard to extrusion and postoperative pain.

Materials and Methods  Sixty-four patients requiring endodontic treatment of single-rooted maxillary teeth with necrotic pulps were included in this study. The root canal treatments were performed in a single visit using a size 40.06 single-file reciprocating system under 2.5% NaOCl irrigation. After irrigation with 17% ethylenediaminetetraacetic acid (EDTA) and 2.5% NaOCl, the canals were dried and randomly divided into two different groups ( n = 32) depending on the sealer used: resin-based group (RG) in which the canals were filled with the AH Plus, and the bioceramic group (BG) in which the canals were filled with the Sealer Plus BC. Ibuprofen (600 mg) was prescribed every 6 hours if the volunteers experienced pain. The patients registered their pain sensation in a visual analog scale (VAS) card, ranging from 0 to 10 at 24-hour, 48-hour, 72-hour, and 1-week intervals. Statistical analysis  For statistical analysis, the level of significance was set at p < 0.05.

Results  Sealer extrusion occurred in nine patients of the RG and in 19 patients of the BG ( p < 0.05). The average pain level at 24-hour and 48-hour intervals was, respectively, 1.46 ± 1.96 and 0.44 ± 0.86 for RG, and 1.21 ± 2.09 and 0.09 ± 0.38 for BG. There was no report of pain after 48 hours. The mean number of tablets taken for pain relief was 0.03 ± 0.17 for RG and 0.06 ± 0.24 for BG. No statistically significant difference was found with regard to pain level and intake of pain killer tablets ( p > 0.05).

Conclusions  The BG sealer presented significantly more extrusion than the RG sealer. Sealer extrusion was not associated with pain. The average pain level and the mean number of tablets taken for pain relief were similar in both groups.

Effectiveness of a reciprocating single file, single cone endodontic treatment approach: a randomized controlled pragmatic clinical trial

OBJECTIVES

To compare the root filling quality, the sealer extrusion, and the healing rates of apical lesions addressed via two endodontic treatment approaches. The hypothesis tested was that both techniques present similar apical periodontitis healing results.

MATERIALS AND METHODS

This study was a parallel-design, pragmatic, and randomized clinical trial. One hundred twenty anterior teeth with necrotic pulps and apical periodontitis were randomly allocated to be either instrumented with hand files and obturated with the lateral compaction technique or instrumented with a single file in a reciprocating movement and obturated with a single-cone technique. The root canal filling quality, the occurrence of sealer extrusion, and apical periodontitis healing were the outcomes of interest. Data were analyzed through chi-square analysis, and the odds ratio for healing was adjusted using a logistic regression model (α = 0.05).

RESULTS

No significant differences were observed between the endodontic techniques regarding the root filling quality or sealer extrusion. Six months after treatment, both endodontic techniques presented equivalent results regarding apical periodontitis healing. The healing rate was affected only by the periapical status at baseline.

CONCLUSIONS

The obturation of the root canal of the anterior teeth using reciprocating file-matched single cones presented a similar quality to that obtained with manual instrumentation followed by the lateral condensation technique. Similar healing rates of apical lesions were also observed.

CLINICAL RELEVANCE

For treating anterior teeth with apical periodontitis, a reciprocating single-file, single-treatment protocol was as effective as a traditional protocol combining hand instrumentation and the lateral compaction obturation technique.

Relationship between unintentional canal overfilling and the long-term outcome of primary root canal treatments and nonsurgical retreatments: a retrospective radiographic assessment

AIM

To determine retrospectively the long-term radiographic outcome of root canal treatments and root canal retreatments with unintentional root canal overfilling.

METHODOLOGY

A total of 220 root canal treatments (143 primary/77 retreatments) with postoperative unintentional canal overfilling and performed by two endodontists during their 45 years of private practice were included in the study. Lateral condensation techniques and nine different sealers were used. Overfilling was confirmed with a postoperative periapical radiograph and patients were scheduled regularly for recall visits. Average recall time was 4.86 years (maximum = 30 years). Two calibrated observers evaluated the radiographs and determined the long-term outcome using the PAI score pooled in a 3-category scale. The persistence or resorption of the extruded material was registered. The Kappa coefficient (K) was calculated and a logistic regression was used for further analysis. Odds ratios and their 95% CI were estimated.

RESULTS

The level of inter-observer agreement was 66.1%. Primary root canal treatments had a significantly (P = 0.015) greater rate of success (91.6%) than retreatments (81.8%). Tooth location (P = 0.019) was the only other factor that significantly affected the outcome. The type of extruded material, and its resorption or persistence did not relate to the outcome. Persistence of extruded material was significantly affected by tooth location and recall time after treatment.

CONCLUSION

The outcome of root canal treatment with unintentional canal overfilling was not associated with the type of extruded material or its resorption or persistence. The persistence of extruded material did not relate to a favourable or unfavourable outcome.

Do in vitro solubility studies on endodontic sealers demonstrate a high level of evidence? A systematic review

OBJECTIVE

To systematically review the quality of evidence of available in vitro solubility studies on endodontic sealers according to prespecified evidence criteria.

MATERIAL AND METHODS

This systematic review was based on the PRISMA guidelines and the AMSTAR measurement tool. A systematic duplicate search of the literature on endodontic sealer solubility studies was conducted in PubMed and Embase databases (until 18 October 2017). Mapping terms to subject headings and free text terms were used and combined with hand searching before exclusion of duplicates. Studies specifically dealing with endodontic sealer solubility were selected. The evidence level was graded (low, medium or high) independently by two investigators following systematic data extraction in pilot forms, which was based on prespecified evidence criteria and the modified CONSORT checklist for in vitro studies on dental materials.

RESULTS

The search retrieved 1053 articles, from which 88 were assessed in full. From the 63 articles retained in the final analysis, 11 were classified as having moderate and 52 as low quality of evidence (0 high). The studies graded as low had low sample size (n < 10) and/or insufficient details to allow replicability. Most of the studies did not conform to the modified CONSORT checklist and did not include parameters considered relevant in the prespecified criteria.

CONCLUSIONS

Existing in vitro studies on the solubility of endodontic sealers do not demonstrate a high quality of evidence. Most of these studies do not present systematic reporting nor employ relevant parameters prespecified in our evidence criteria.

Evaluation of apoptosis/necrosis and cytokine release provoked by three root canal sealers in human polymorphonuclears and monocytes

AIM

To evaluate the in vitro cytotoxicity and cytokine release of three fresh root canal sealers and to determine the type of cell death they induce.

METHODOLOGY

The sealers tested were Sealer 26 (S26), AH Plus (AHP), and Endosequence BC Sealer (END). Fresh sealers were cultivated in contact with monocytes and polymorphonuclears (PMNs) obtained from the peripheral blood of humans. Cell viability, apoptosis and necrosis were analysed at 4 h (PMNs) or 24 h (monocytes) using Annexin-V and propidium iodide in a cytometer. The supernatants were used to quantify Interleukin (IL)-4, IL-6, IL-10, IL-12 and tumour necrosis factor-α (TNF-α) in monocytes and IL-8 in PMNs by ELISA. One-way ANOVA and the Tukey post-test were used to compare data for cytotoxicity, and the multiple T-test was used to determine the differences between sealers in the release of cytokines that were statistically significant.

RESULTS

After 4 h of treatment, S26 was associated with greater cell viability than the other sealers (P < 0.05) in the PMN culture and had similar values of necrosis as END (P > 0.05). After 24 h of treatment, AHP and END had greater monocyte cell viability than S26 (P < 0.05), which had more necrosis (P < 0.05). END had the lowest levels of IL-12 compared to the other sealers (P < 0.05) and higher levels of IL-6 compared to S26 (P < 0.05). The tested sealers did not differ in the release of IL-8, IL-10, TNF-α and IL-4 (P > 0.05).

CONCLUSIONS

The effect of toxic agents released varied depending on the cell type studied. The composition of the sealers appeared to alter the form of self-regulation in the production of these cytokines by cells.