Resin-based Root Canal Sealer Research Articles

Cytotoxicity and Genotoxicity of Epoxy Resin-Based Root Canal Sealers before and after Setting Procedures.

Epoxy resin-based sealers are commonly used for successful endodontic treatment. This study aimed to evaluate the cytotoxicity and genotoxicity of epoxy resin-based sealers under unset and set conditions. Three epoxy resin-based sealers were used: Adseal, AH Plus, and Dia-Proseal. To test cytotoxicity, an agar overlay test and a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay were performed using unset and set sealers on L929 mouse fibroblasts. The genotoxicity test of the comet assay was performed using the same cell line. Extract dilutions in the culture media were used as test materials for the MTT and comet assays. The comet tail produced by the damaged DNA was calculated by image analyses. Statistical analyses were performed using one-way analysis of variance and Tukey’s post hoc test. Unset sealers did not show defined decolorized areas. Hardened specimens of resin-based sealers showed circular discolored zones in the agar overlay test. Dia-Proseal was the least cytotoxic after hardening. These results were confirmed in the MTT assay. Cell viability was significantly higher in cells treated with hardened sealers in both groups than that in cells treated with freshly mixed sealers in the MTT assay. Unset AH Plus® and Dia-Proseal™ significantly increased cell viability with decreasing dilution. Adseal™ was the least cytotoxic. Freshly mixed Adseal™ was more genotoxic when freshly mixed than when set. Unset epoxy resin-based sealers were generally more cytotoxic and genotoxic than set materials. Cytotoxicity does not always match the genotoxicity results; therefore, various test tools are required to test toxicity. It is necessary to properly evaluate the toxic effects to establish a biocompatibility test that mimics clinical conditions.

Do resin-based root canal sealers cause more postoperative pain than other sealers? A systematic review of clinical studies and meta-analysis.

To evaluate whether root canal obturation with resin-based sealers increases the incidence and intensity of postoperative pain compared to other sealer types. Medline, Scopus, Web of Science, Google Scholar, Cochrane Library, and gray literature were searched through December 2020. Clinical studies evaluating postoperative pain after obturation with resin-based sealers and other sealer types were included. Risk of bias was assessed through the Cochrane RoB 2.0 tool for randomized clinical trials (RCTs) and ROBINS-I tool for non-randomized clinical trials (nRCTs). Pooled relative risks (RR), standardized mean differences (SMD), and 95% confidence intervals were calculated for quantitative analyses. Of 524 studies, 11 clinical studies (eight RCTs and three nRCTs) involving 1,123 teeth were included. Four studies were assigned low risk of overall bias while seven studies presented high risk of overall bias. Quantitative analyses were performed with six studies for pain incidence, five studies for pain intensity, and four studies for analgesic intake. There was no significant difference between resin- based sealers and other sealer types in postoperative pain incidence at 24 hours (RR 1.102, P = .53), 48 hours (RR 0.943, P = .93), 72 hours (RR 1.019, P = .93), and 1 week (RR 0.559, P = .31), in pain intensity at 12 hours (SMD 0.100, P = .35), 24 hours (SMD 0.090, P = .25), and 48 hours (SMD 0.217, P = .26), and in analgesic intake at 24 hours (RR 2.253, P = .15) and 72 hours (RR 0.650, P = .59). Based on the available evidence, resin-based sealers do not increase the postoperative pain incidence, intensity, and analgesic intake compared to other sealer types.

Impact of Water Solubility on Chemical Composition and Surface Structure of Two Generations of Bioceramic Root Canal Sealers

Aimed to evaluate the effect of water solubility on chemical properties and surface structure of bioceramic-based (BC-HiFlow and BC-EndoSeqence) compared with resin-based (Adseal) root canal sealers. Fresh mix was inserted into polyethylene mold (n = 10) and subjected to Vicat needle to evaluate the setting time. The set discs were analyzed by Fourier transform infrared (FTIR) spectroscopy then immersed in deionized water for 1, 7, 14 and 28 days. The solubility%, pH changes, released calcium (Ca2+), phosphate (PO43−) and silicon (Si4+) ions were evaluated after each immersion period. The discs were analyzed by scanning electron microscopy/Energy dispersed X-ray (SEM/EDX) before and after solubility test. Although FTIR detected similar composition of both bioceramic-sealers, BC-EndoSequence determined the prolonged setting times. At the end of solubility test, both bioceramic-sealers exhibited significant greater solubility (>3%), alkaline pH (>11) at p < 0.001. Adseal displayed the significant greatest Ca2+ and PO43− released, while BC-HiFlow displayed the significant greatest Si4+ release (p < 0.001). SEM revealed voids and pores on the surface of all tested sealers with the greatest value on Adseal surface. In conclusion, although both bioceramic-sealers had high solubility, BC-Hiflow complied the ISO standard regarding setting time and least surface micropores better than that of BC-EndoSequence.

Comparative Evaluation of the Effect of Herbal Irrigants on the Push-out Bond Strength of Epoxy Resin Based Sealer to Root Dentin: An In-vitro Study

Introduction: Favourable outcome of root canal treated teeth depends on the irrigants used, Sodium Hypochlorite (NaOCl) is one of the most commonly used irrigants in endodontic treatment. NaOCl has cytotoxic effects; limited ability to eliminate bacteria, along with jeopardizing of the bond strength between epoxy resin-based sealers and root dentin. Contemporary medicine orchestrates the use of biological medical extract from natural plants. Herbal alternatives are coveted as they are readily available, less expensive, have enhanced shelf life and low toxicity. Despite that, literature is sparse regarding the effect of herbal irrigants on Push-out Bond Strength (PBS) of sealer to root dentin. Aim: To compare and assess the effect of the PBS of epoxy resin based root canal sealer to root dentin following the use of two novel herbal irrigants,10% proanthocyanidins (PAs) and 2% Azadirachta indica (neem extract) with 3% sodium hypochlorite. Materials and Methods: This in-vitro study was conducted in the Department of Conservative and Endodontics at KLE VK Institute of Dental Sciences, Belagavi, Karnataka, India, between June 2019 and August 2019. The study was done on 30 extracted single rooted human mandibular premolar teeth, of which root canals were prepared using rotary instruments. The use of standard susceptibility tests {Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentration (MBC)} was done to determine appropriate concentration of the irrigant against E. faecalis. The teeth samples were randomly divided into 3 groups (n=10 each). Group 1 has teeth irrigated with 3% NaOCl (control group), Group 2 has teeth irrigated with 10% grape seed extract (10% proanthocyanidins) and Group 3 has teeth irrigated with 2% Neem leaf extract (2% Azadirachta indica). Obturation of all the three groups was done with F3 gutta percha and AH Plus sealer followed by push-out bond strength testing using universal testing machine. One way ANOVA and Tukey’s Post hoc tests were used for statistically analysing the data. The p-value<0.05 was considered as statistically significant. Results: Group 2 had significantly higher push-out bond strength as compared to Group 3 (p-value <0.001). However, there was no significant difference seen between Group 2 and Group 1 (p-value= 0.207). Conclusion: It was concluded that the PBS of 10% Proanthocyanidins was the highest, followed by 3% NaOCl and Azadirachta indica. However, biocompatibility and safety of these novel intracanal irrigants has to be assessed with the help of further clinical and in-vitro experiments to validate these findings.

Dissolving efficacy of xylene on epoxy resin-based and bioceramic-based root canal sealers

Background: Epoxy resin-based and bioceramic-based root canal sealers are used in endodontic treatment as root canal obturation materials because they are considered to have many advantages. The complete removal of these materials during root canal retreatment is crucial in order to ensure adequate disinfection. Due to the difficulty in accessing root canal ramifications, removal of these filling materials without damaging the teeth can be successfully achieved using endodontic solvents. Objective: The aim of this study was to evaluate the solubility of two types of root canal sealers in xylene used in endodontics. Methods: A total of 34 epoxy resin and bioceramic samples were stored for 72 h in an incubator to set. The samples were then immersed for 2 min in 1 mL of xylene. The excess xylene on the samples was drained with an absorbent paper and stored in an incubator for 24 h to dry. The pre- and post-immersion weight of the samples was measured using a digital analytical scale, then the weight difference between the groups was analyzed using the independent t test at a 5% significance level. Results: No significant difference was observed between the epoxy resin-based root canal sealer group and the bioceramic-based root canal sealer group (P ≥ 0.05). Conclusion: Xylene endodontic solvent has a similar efficacy for removing epoxy resin-based and bioceramic-based root canal sealers in in vitro study.

Influence of the use of chelating agents as final irrigant on the push-out bond strength of epoxy resin-based root canal sealers: A systematic review.

This systematic review (PROSPERO - CRD42020150722) was performed to answer the following question: Does the use of chelating agents affect the dislodgment resistance of epoxy resin-based root canal sealers? A search was conducted in PubMed, EMBASE, Scopus, LILACS and Web of Science, hand searching of two endodontic journals and grey literature until September 2020. Extracted data included: teeth used, sample size, root canal preparation, irrigant, chelating solution, neutralisation solution, type of resin-based sealer and obturation approach, storage method and duration, root third and slice thickness, plunger dimension and loading direction and the push-out testing parameters and values. The search retrieved a total of 2.389 studies. After analysis, 12 studies fulfilled the eligibility criteria and were included. Most of the final irrigation protocols with chelating agents had a positive impact and promoted an improvement in the dislodgment resistance of epoxy resin-based sealers to the root dentin.

The effect of two rotary and two reciprocating NiTi systems on postoperative pain after root canal retreatment on single-rooted incisor teeth: A randomized controlled trial.

This randomized clinical trial aimed to assess the effect of two rotary (ProTaper Retreatment + ProTaper Gold and Hyflex EDM) and two reciprocating (Reciproc Blue and WaveOne Gold) NiTi systems on postoperative pain after root canal retreatment on single-rooted incisor teeth. One hundred and eighty patients scheduled for root canal retreatment were randomly assigned to one of the four groups according to the NiTi system (ProTaper Retreatment + ProTaper Gold, Hyflex EDM, Reciproc Blue or WaveOne Gold) used for the removal of root canal fillings and further canal preparation. The working length was determined to be 1mm shorter than the '0.0' mark of the apex locator. Root canals were filled with gutta-percha and an epoxy resin-based root canal sealer using a lateral compaction technique. The teeth were restored using a resin composite material. A single operator performed the retreatments in a single visit. The incidence and intensity of postoperative pain were rated on a numeric rating scale by patients 24, 48 and 72h after retreatment. The number of analgesic tablets (400mg Ibuprofen) taken by patients was also recorded. Data were analysed using the Mann-Whitney U, Wilcoxon and chi-square tests. For the intensity of postoperative pain, the difference between the four groups was not significantly different (p>.05). No significant difference was found between the groups in terms of analgesic medication intake (p>.05). The rotary and reciprocating NiTi systems tested in this study were associated with similar intensity of postoperative pain and intake of analgesics following root canal retreatment on single-rooted incisor teeth completed in one visit.

A comparative evaluation of the sealing ability of two calcium silicate based sealers and a resin epoxy-based sealer through scanning electron microscopy and bond strength

Aim: this study aimed to compare the sealing ability of two types of commercially available calcium silicate bioceramic based root canal sealers and a resin based root canal sealer. Methods: Twenty one single-rooted teeth were used, samples (n= 21) were randomly divided into three groups according to the sealer used (group A; ADSEAL, group B; Wellroot, group C; Ceraseal). Roots were then cleaved longitudinally in the labiolingual direction; all samples were then sectioned at three, six, and nine mm from the root tip. The penetration of sealers into the dentinal tubules was examined at 1000x with a scanning electron microscope. Data were tested for normality using Shapiro Wilk test. ANOVA test was used for analyzing normally distributed data followed by Bonferroni post hoc test for pair-wise comparison. Significance level p≤0.001. Results: groups B and C showed better sealing ability than group A in all the three sections. The coronal section showed higher sealing ability than the middle section followed by the apical section in the three tested groups. Conclusion: it can be concluded that both calcium silicate-based sealers had better sealing ability and higher bond strength than the resin epoxy- based sealer.

Comparison of Postobturation Pain Experience after Apical Extrusion of Calcium Silicate– and Resin–Based Root Canal Sealers

IntroductionThis study compared the intensity of postobturation pain after unintentional apical extrusion of calcium silicate–based root canal sealers (EndoSequence BC Sealer [Brasseler USA, Savannah, GA] and Bio-C Sealer [Angelus, Londrina, PR, Brazil]) with a resin-based sealer (AH Plus; Dentsply Sirona, York, PA). MethodsA total of 330 patients referred for root canal treatment on molar teeth with asymptomatic irreversible pulpitis were recruited. Root canals were prepared using WaveOne Gold instruments (Dentsply Sirona) in a crown-down technique and irrigated with 2% chlorhexidine gel and saline solution. Next, patients were randomly distributed into 3 groups according to the root canal sealer used (n = 110): AH Plus, BC Sealer, and Bio-C Sealer. Root canal filling was then accomplished with a vertical compaction technique. Patients presenting with an unintentional extrusion of sealers (n = 13/group) were assessed for postobturation pain experience using a visual descriptor scale ranging from 0–10 at 6-, 12-, 24-, and 48-hour and 1-week intervals after treatment. Mixed analysis of variance repeated measures were used to assess the results (α = 0.05). ResultsThe extrusion rate was similar for all sealers (~12%). There was no significant difference in the postobturation pain results between the root canal sealers evaluated (P > .05). However, after the time interval of 12 hours, AH Plus (P = .04073) and Bio-C Sealer (P = .04327) demonstrated a significant reduction in pain, whereas BC Sealer did not show differences in pain intensity, even in the maximum period evaluated of 1 week (P > .05). ConclusionsThe occurrence of unintentional apical extrusion of calcium silicate–based root canal sealers presents similar postoperative pain results compared with resin-based sealers with low-intensity pain.

Evaluation of the Effect of Final Rinse with Chitosan Nanoparticles and EDTA on the Push-out Bond Strength of Resin-based and Bioceramic-based Root Canal Sealers (A Comparative In Vitro Study)

Evaluation of the Effect of Final Rinse with Chitosan Nanoparticles and EDTA on the Push-out Bond Strength of Resin-based and Bioceramic-based Root Canal Sealers (A Comparative In Vitro Study)

Evaluation of the cytocompatibility of methacrylate resin-based root canal sealers with osteoblast-like cells.

This study compared the cytocompatibilities of three methacrylate resin-based root canal sealers [MetaSEAL Soft (MSS), Hybrid Root SEAL (HRS), and Superbond Sealer (SBS)] in either freshly mixed or set conditions using the Kusa A1 osteoblastic cell line. The three sealers and an epoxy resin-based sealer (AH Plus; AHP) were extracted in culture medium; cell growth and osteogenic properties were analyzed. Cell adhesion on set sealers was analyzed with scanning electron microscopy. The respective extents of cell growth were as follows in freshly mixed and set sealer extracts: SBS>MSS>AHP>HRS and SBS=AHP>MSS>HRS. Light irradiation of MSS and HRS increased the cell growth of set sealer extracts. Set SBS, MSS, and AHP did not alter expression of osteogenic genes or formation of mineralized nodules. Attached cells were observed only on SBS. In conclusion, the four sealers exhibited varying degrees of compatibility to osteoblasts; SBS and HRS were the most and least compatible, respectively.

Solubility of bioceramic- and epoxy resin-based root canal sealers: A systematic review and meta-analysis.

This systematic review and meta-analysis evaluated whether epoxy resin-based root canal sealers present an increased solubility than calcium silicate-based root canal sealers. A systematic search was performed in the following databases: PubMed, Science Direct, Scopus, Web of Science and Open Grey. The inclusion criteria consisted of invitro studies that compared the solubility of epoxy resin-based and calcium silicate-based sealers. The quality assessment and data extraction of the selected articles were performed. The meta-analysis of the pooled data and the subgroups according to the root thirds were carried out using the RevMan software (P < 0.05). After the duplicate removal and eligibility criteria assessment, a total of 22 studies were included all of them were considered as having a low risk of bias. The meta-analysis demonstrated overall lower solubility of AH Plus. AH Plus presented lower solubility than Bio-C Sealer, BioRoot RCS, MTA Fillapex, Sealer Plus and Total Fill BC Sealer.

Effect of Sodium Thiosulfate on Interfacial Adaptation and Penetration of an Epoxy Resin-Based Root Canal Sealer.

Our study evaluated the impact of sodium thiosulfate (ST) irrigation, subsequent to sodium hypochlorite (NaOCl) and just before root canal filling, on the filling quality (interfacial adaptation and penetration segment) of an epoxy resin-based root canal sealer. Twenty single-rooted human teeth were prepared with the ProTaper system. The specimens were then divided into the following groups: 5.25% NaOCl irrigation (NaOCl group) and 5.25% NaOCl irrigation+0.5% sodium thiosulfate (NaOCl+ST group). The root canals were filled using single-cone technique with ProTaper F3 cones and AH-Plus sealer, labeled with rhodamine B dye to allow analysis under a confocal laser scanning microscopy (CLSM). All samples were sectioned at 2, 4, and 6 mm from the apex and prepared for CLSM analysis. The percentage of voids, gaps and dentinal sealer penetration segment of the canal were calculated at the apical, middle and coronal thirds. The non-parametric Mann-Whitney statistical test was used at 5% significance level. Higher percentage of gaps and voids were observed at all root thirds of the NaOCl group when compared to the NaOCl+ST group (P<0.05). There was a significant increase in the penetration segment of NaOCl+ST group at the coronal and middle root third when compared to the NaOCl group (P<0.05). Our in vitro results showed that the use of ST as an antioxidant agent after NaOCl irrigation promoted a better interfacial adaptation and penetration of epoxy resin-based root canal fillings.

Comparative evaluation of retreatability of calcium silicate-based root canal sealers and epoxy resin-based root canal sealers in curved canals-An In-Vitro micro-CT analysis.

To compare and evaluate the retreatability of calcium silicate-based root canal sealers and epoxy resin-based root canal sealers in curved canals using micro-CT scanning. Forty-five maxillary molars with curved roots were selected after confirming with the Schneiders test. Teeth were decoronated near the cemento-enamel junction and moderate to severely curved canals were selected for the study using cone-beam computed tomography. All the samples were subjected to pre-operative micro-CT scanning. Cleaning and shaping were done using step-back preparation, obturation was done using lateral compaction technique, and homogeneous obturation was achieved. All the specimens were kept in 10 mL of phosphate buffered-saline solution at a pH of 8.4 for 48 h and transferred to a plastic container containing moistened foam with 10 mL of phosphate- buffered saline solution, and stored at 37 °C with 100% relative humidity for 4 months. Retreatment was performed for all the samples using Protaper universal retreatment files. Micro-CT scanning was performed to compare and evaluate the remaining sealer volume and resultant cracks formed in the root canal after retreatment. The volume of sealer remaining in the root canal and the length of a crack within the groups were analysed using kruskal-Wallis test and among the groups using post-hoc scheffe test showed that more sealer present in the Diaproseal sealer followed by MTA Fillapex and Bioroot RCS and more crack length was seen in Diaproseal sealer followed by MTA Fillapex and no visible cracks were seen in Bioroot RCS, which had statistically significant results with a P value of < 0.05. Within the limitations of the study it was concluded that in-terms of retrievability, Diaproseal sealer was the best among the tested groups followed by MTA Fillapex and Bioroot RCS.

The effect of two calcium silicate-based and one epoxy resin-based root canal sealer on postoperative pain: a randomized controlled trial.

To compare the effect of two calcium silicate-based (Endoseal MTA and EndoSequence BC Sealer) and an epoxy resin-based (AH Plus) root canal sealer on postoperative pain following single-visit root canal treatment on molar teeth. Patients (n=90) having one first or second molar tooth diagnosed with asymptomatic irreversible pulpitis were randomly divided into three groups according to the sealer used (n=30) and were treated by two endodontists having at least 10years of experience. All patients received a single-visit root canal treatment. After the treatments, postoperative pain scores and analgesic intake were recorded at 6, 12, 24 and 48h, and 3, 4, 5, 6 and 7days. The data were analysed statistically using non-parametric Kruskal-Wallis tests (for the comparisons of the age and VAS scores), Friedman tests (for the assessments of the changes in pain scores over time), chi-squared tests (for the comparisons of categorical variables) and Spearman's correlation test (for the correlation assessments of the age and gender factors with postoperative pain; α=0.05). There were no significant differences amongst the groups in terms of postoperative pain at any time-points assessed (P>0.05) nor for analgesic intake of patients amongst the groups (P>0.05). Analgesic intake decreased significantly after 12h in all groups (P<0.05). The sealers tested in this study were associated with similar levels of postoperative pain and were associated with a similar intake of analgesics.

Effect of heat application on the physical properties and chemical structure of calcium silicate-based sealers.

To determine the effect of heat application on the setting and chemical properties of HiFlow BC Sealer and compare to other calcium silicate (CSBS) and epoxy resin-based root canal sealers. AH Plus, BioRoot RCS (BioRoot), Endosequence BC (Endosequence), and HiFlow BC (HiFlow) sealers were placed at 37 °C or subjected to heat at 200 °C for 10 or 30 s, followed by incubation at 37 °C in a humidified incubator during experiments. Setting time, viscosity, and flow were assessed, and changes in chemical structure were evaluated using the Fourier-transform infrared spectroscopy (FTIR). Thermogravimetric analysis was also used to evaluate the weight change (%) of the sealers upon heating from room temperature to 37 °C or 200 °C at a rate of 20 °C/min. Data were analyzed using a two-way ANOVA with a Bonferroni post-hoc test (p = 0.05). Application of heat extended the setting time for Endosequence and HiFlow but resulted in a faster setting of AH Plus and BioRoot. The highest flow and lower viscosity were observed in HiFlow at high temperature (p < 0.05), whereas the lowest flow with the highest viscosity and greatest weight loss were observed in BioRoot after heat application (p < 0.05). FTIR spectra demonstrated no changes to functional groups after heat application, except for the strong H-O-H absorption peak corresponding to water in BioRoot. Endosequence and HiFlow showed similar chemical properties with a higher flow and lower viscosity in HiFlow after heat application. Heat application resulted in reduced flow, increased viscosity, and weight loss for BioRoot. The setting of AH Plus was fastened with heat, while its weight loss, viscosity, and flow characteristics were stable. HiFlow, Endosequence, and AH Plus can be all used with WVC obturation techniques. Heat application resulted in minor changes in their physical properties including setting time, flow, weight loss, and chemical properties, while BioRoot showed a significant amount of weight loss, increase in viscosity, and reduced flowability after heat application.

Adhesion capacity of bioceramic and resin-based root canal sealer to root dentin: an integrative review

Objetivo: comparar a capacidade de adesão do cimento biocerâmico EndoSequence BC e do cimento resinoso AH Plus através de uma revisão integrativa. Material e Métodos: os bancos de dados online Medline/PubMed, Scopus, Web of Science e BVS foram utilizados para a revisão da literatura. Os critérios de elegibilidade incluíram artigos disponíveis na íntegra nas bases de dados pesquisadas, em inglês, e o conteúdo referente à adesão do cimento Endosequence BC sealer em comparação ao AH Plus. Resultados: foram encontrados 45 artigos. Após a remoção duplicada, 22 artigos foram selecionados. Após a leitura dos resumos, textos completos e aplicação dos critérios de inclusão, foram incluídos no total oito artigos. Em relação à capacidade de adesão dos cimentos testados, o AH Plus apresentou melhor adesão do que o cimento BC sealer em três artigos e menor adesão em dois artigos. Força de adesão semelhante foi observada entre os grupos em três estudos. Conclusões: com base nos estudos incluídos, o AH Plus apresenta maior resistência de união quando comparado ao BC Sealer

Novel Bioactive and Therapeutic Root Canal Sealers with Antibacterial and Remineralization Properties.

According to the American Dental Association Survey of Dental Services Rendered (published in 2007), 15 million root canal treatment procedures are performed annually. Endodontic therapy relies mainly on biomechanical preparation, chemical irrigation and intracanal medicaments which play an important role in eliminating bacteria in the root canal. Furthermore, adequate obturation is essential to confine any residual bacteria within the root canal and deprive them of nutrients. However, numerous studies have shown that complete elimination of bacteria is not achieved due to the complex anatomy of the root canal system. There are several conventional antibiotic materials available in the market for endodontic use. However, the majority of these antibiotics and antiseptics provide short-term antibacterial effects, and they impose a risk of developing antibacterial resistance. The root canal is a dynamic environment, and antibacterial and antibiofilm materials with long-term effects and nonspecific mechanisms of action are highly desirable in such environments. In addition, the application of acidic solutions to the root canal wall can alter the dentin structure, resulting in a weaker and more brittle dentin. Root canal sealers with bioactive properties come in direct contact with the dentin wall and can play a positive role in bacterial elimination and strengthening of the root structure. The new generation of nanostructured, bioactive, antibacterial and remineralizing additives into polymeric resin-based root canal sealers are discussed in this review. The effects of these novel bioactive additives on the physical and sealing properties, as well as their biocompatibility, are all important factors that are presented in this article.

The effect of nonthermal plasma on the push-out bond strength of two different root canal sealers

An optimum bonding between the sealer and dentin is important for impermeable root canal filling and many procedures were applied to improve root canal dentin and in turn the bond strength between the sealer and dentine. There is lack of sufficient data on the effect of nonthermal plasma application on the bond strength of sealers to the root canal dentin. The purpose of this study was to evaluate the effect of NAP on the push-out bond strength (PBS) of a bioceramic and resin-based root canal sealer (RCS) to root canal dentin. Forty single-rooted mandibular premolars were decoronated. After preparation and final irrigation, the specimens were divided into four groups (n = 10). Group AH: Root canals were filled with gutta-percha (GP) and AH Plus RCS, Group P-AH: Root canals were filled with GP and AH Plus RCS following the NAP application, Group BC: Root canals were filled with GP and Endosequence BC RCS, and Group P-BC: Root canals were filled with GP and Endosequence BC RCS following the NAP application. Then roots were sectioned horizontally to obtain ~1 mm thick dentin disks. PBS test was performed to the second (coronal) and fourth (middle) slices. Data were analyzed with the Kruskal-Wallis and t-test. There was a statistically significant difference among the groups for both coronal and middle regions (P < 0.05). P-BC group showed higher PBS than AH and P-AH groups in the coronal region. P-BC group showed higher PBS than the other groups in the middle region. The use of NAP did not influence the push-out bond strength of AH-Plus sealer to the root canal dentin. The Endosequence-BC sealer showed a better bond strength than the AH-Plus sealer after NAP application.

Effect of final irrigant on depth of tubular penetration of resin-based root canal sealer and bioactive sealers using confocal laser scanning microscope

Background: Deep dentin tubular penetration of the sealer provides a three dimensional sealing of root canal space Aim: To evaluate the effect of final irrigant on depth of tubular penetration of resin based root canal sealer and bioactive sealers using Confocal Laser Scanning Microscope (CLSM) Materials and Method: Ninety- six freshly extracted human mandibular first premolar teeth were decoronated at 15 mm from the apex. Cleaning and shaping procedure was accomplished using Hyflex CM rotary files till F3. The sample were divided into three groups(n=32) according to final irrgant used : Group A (17 % EDTA), Group B (QMix 2 in 1), Group C (Distilled water). The final irrigation in each respective group was performed with EndoVac system. The samples were further subdivided into 4 subgroups (n=8) according to the type of sealer used for obturation with 6% guttapercha cones - Subgroup I (AH Plus), Subgroup II (Gutta Flow Bioseal), Subgroup III ( Endosequence BC ), Subgroup IV (EndoSeal MTA). Two mm horizontal sections were obtained at 2 mm (apical sections), 5 mm (middle sections) and 7 mm (coronal sections) from the root apex using CLSM to evaluate the maximum depth and percentage of sealer penetration into the dentinal tubules by using Kruskal-Wallis test for overall analysis and a series of Mann-Whitney U tests for pairwise comparison. Result: Endosequence BC showed maximum depth of penetration and penetrated percentage perimeter, while Gutta Flow Bioseal showed least values. Q Mix 2 in 1 showed better penetration values than EDTA and distilled water. Conclusion: Irrigants, nature of sealer and level of root canal affected sealer penetratio.