Evaluation of Immediate and Delayed Placement of Post on Sealing ability of Periapical Area: An Original Research.

Objective: The purpose of this research is to compare the effects of post placement-immediate and delayed-on the periapical area's capacity to close after root canal therapy (RCT). Techniques: A random split of sixty recently removed human single-rooted teeth was made into two groups: Group A received immediate post placement, whereas Group B received post placement after seven days. Standard guidelines were followed in the preparation of root canals and the placement of posts. A dye penetration method was used to measure microleakage, a measure of sealing capacity. Findings: Compared to the immediate post placement group (0.62 ± 0.08) (P < 0.001), the delayed post placement group had a considerably lower mean microleakage score (0.35 ± 0.06), showing improved sealing capacity. In conclusion, post implantation done later enhances the periapical area's sealing capacity after RCT. This research underscores the significance of scheduling endodontic treatments to maximize treatment success and improve tooth retention, as well as the possible therapeutic advantages of postponing post implantation.

Evaluation of the Sealing Ability of Various Root Canal Obturation Techniques in Permanent Molars: An In vitro Study.

Background: Achieving a reliable seal in root canal obturation is essential for the success of endodontic treatment. Despite the availability of multiple techniques, the comparative sealing abilities of these methods remain a topic of investigation, particularly in permanent molars. Materials and Methods: This in vitro study involved 60 extracted permanent molars, divided randomly into three groups: Group A (lateral compaction), Group B (thermoplasticized gutta-percha), and Group C (single cone). After instrumentation and obturation, the sealing ability was assessed using a dye penetration method. Arbitrary values were assigned to quantify the extent of dye penetration. Results: The mean dye penetration values were as follows: Group B (thermoplasticized gutta-percha) had the lowest penetration (2.1 ± 0.3 mm), followed by Group A (lateral compaction) (3.5 ± 0.4 mm), and Group C (single cone) exhibited the highest penetration (5.2 ± 0.6 mm). Conclusion: In this study, thermoplasticized gutta-percha demonstrated superior sealing ability compared to lateral compaction and single cone techniques in permanent molars. These findings underscore the importance of selecting an effective obturation technique to ensure optimal seal integrity in root canal therapy.

Evaluation of Immediate and Delayed Placement of Post on Sealing Ability of Periapical Area: An Original Research.

Objective: The purpose of this research is to compare the effects of post placement-immediate and delayed-on the periapical area's capacity to close after root canal therapy. Techniques: A random split of 60 recently removed human single-rooted teeth were made into two groups: Group A received immediate post placement, whereas Group B received post placement after seven days. Standard guidelines were followed in the preparation of root canals and the placement of posts. A dye penetration method was used to measure microleakage, a measure of sealing capacity. Findings: Compared to the immediate post-placement group (0.62 ± 0.08) (P < 0.001), the delayed post-placement group had a considerably lower mean microleakage score (0.35 ± 0.06), showing improved sealing capacity. In conclusion, post implantation done later enhances the periapical area's sealing capacity after root canal therapy. This research underscores the significance of scheduling endodontic treatments to maximize treatment success and improve tooth retention, as well as the possible therapeutic advantages of postponing post implantation.

Assessment of sealing efficacy, radiopacity, and surface topography of a bioinspired polymer for perforation repair.

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.

A Study on Nanoleakage of Apical Retrograde Filling of Premixed Calcium Silicate-Based Cement Using a Lid Technique.

This study aimed to compare the nanoleakage of retrograde fillings with premixed calcium silicate-based putty and mineral trioxide aggregate (MTA), using two different techniques (traditional and Lid). Sixty-four extracted human teeth were decoronated, then root canals and ends were instrumented for retrograde filling and divided into four groups according to the retrograde filling technique: the traditional and the Lid technique. Each group (n = 15) was filled with Ceraseal + Well-Root putty, Well-Root putty, Ceraseal + ProRoot MTA, and ProRoot MTA. The nanoleakage was evaluated using the Nanoflow device (IB Systems) on days 1, 3, 7, 15 and 30. Data were collected twice per second at the nanoscale (nL/s) and calculated after archiving the stabilization of fluid flow. The Kruskal-Wallis and Mann-Whitney U-tests were used for statistical analysis. All groups showed enhanced sealing ability over time. Regardless of filling materials, the Well-Root putty, Ceraseal+Well-Root putty, and Ceraseal+ProRoot MTA groups indicated less nanoleakage than the ProRoot MTA group in the first week of evaluation (p < 0.05). Although all groups did not show significant differences after 2 weeks, the Ceraseal+ProRoot MTA group leaked less than ProRoot MTA on Days 3 and 7 (p < 0.05). The scanning electron microscopic examined good adaptation to the cavity wall, which was similar to nanoleakage results. Premixed calcium silicate-based putty retrograde filling material alone and using the "lid technique" were shown to be faster and less prone to nanoleakage when compared to MTA.

Sealing Ability Comparison of Three Different Obturating Systems to Intraradicular Dentin-An In Vitro Stereomicroscopic Study.

Background: Different obturation techniques are being used to improve canal sealing, thereby minimizing marginal leakage. Aims and Objectives: To evaluate the marginal leakage of three different obturating materials and techniques using stereomicroscope. Materials and Methods: Thirty freshly extracted maxillary anterior teeth were collected and were divided into three groups of 10 each for which the biomechanical preparation was done. The teeth were divided into three experimental groups according to the obturation material and technique used, Group I: gutta-percha with AH Plus root canal sealer (lateral condensation): Group II: thermoplasticized gutta-percha technique-non-carrier-based (calamus) with AH Plus sealer (backfill): Group III: C point (self-sealing root canal obturating system) with bioceramic sealer (single cone). Each specimen was subjected for testing apical sealing ability. The values of microleakage associated with different root canal sealers were evaluated using a stereomicroscope. Results: There was no statistically significant difference in the mean scores of apical dye penetration/leakage among all the three groups (P = 0.091), whereas Group I showed a higher degree of apical leakage than the other techniques tested. Conclusion: None of the tested filling materials provided a gap-free or void-free root canal filling; however, thermoplasticized gutta-percha is used with AH Plus sealer exhibited less voids and gaps when compared to other tested materials.

The effect of 2% chlorhexidine iontophoresis on dentin sealing ability of etch-and-rinse adhesive: An in vitro study.

Background/purpose: Iontophoresis could enhance the delivery of chlorhexidine into oral tissue. This study aimed to determine the effect of 2% chlorhexidine iontophoresis (CHI) on the sealing ability of etch-and-rinse adhesive in human dentin using hydraulic conductance (HD) measurement, scanning electron microscopy and energy dispersive x-ray spectroscopy (SEM-EDS). Materials and methods: Thirty-nine sound dentin specimens were prepared from 39 extracted intact third molars. Thirty specimens were used for HD measurement and randomly divided into 3 equal-sized groups; (1) No chlorhexidine treatment (control), (2) passive chlorhexidine treatment (CHT) and (3) CHI on acid-etched dentin. Each dentin surface was treated with etch-and-rinse adhesive. HD of each specimen was measured before treatment, after immediate bonding and after 14 days. The other 9 specimens were subjected to SEM-EDS analysis of the acid-etched dentin and the dentin treated with CHT and CHI. ANOVA test and Student-Newman-Keuls method were used for statistical analysis. Results: After bonding, there was no significant difference in percentage decrease of HD among the treatment groups (P > 0.05). After 14 days, CHI and CHT groups had greater percentage decrease of HD than the control (P < 0.001 and P = 0.009, respectively). Under SEM-EDS analysis, acid-etched dentin with CHI presented opened dentinal tubule orifices and more chlorhexidine precipitates on dentin than the dentin with CHT, which strongly related to a higher percentage of chloride ions on the CHI dentin surface (P < 0.001). Conclusion: The use of CHI on acid-etched dentin had a positive effect on dentin sealing ability of etch-and-rinse adhesive.

Sealing ability of various endodontic sealers with or without ethylenediaminetetraacetic acid (EDTA) treatment on bovine root canal.

This study investigated the wettability and consistency of various endodontic sealers, both inorganic and organic, and evaluated their sealing ability of root canals using the single-cone obturation technique, with and without ethylenediaminetetraacetic acid (EDTA) treatment. Bovine root canals were endodontically prepared and filled in preparation for the dye penetration test with toluidine blue solution. All sealers exhibited contact angles similar to or lower than dentin and displayed superior consistency. Among the sealers, organic sealers used without EDTA treatment showed reduced dye penetration compared to inorganic sealers. However, some inorganic and organic sealers showed dye penetration in the sealer and dentin of root canals subjected to EDTA treatment. In conclusion, the single-cone obturation technique, combined with these endodontic sealers, achieved close contact with root canal dentin due to their wettability and consistency. However, the sealing ability of certain sealers was influenced by EDTA treatment.

Evaluation of Postoperative Pain in Response to Polydimethylsiloxane and Calcium Silicate-Based Endodontic Sealers Using the Visual Analog Scale (VAS).

BACKGROUND: The main purpose of obturation is to achieve a complete three-dimensional sealing of the pulp space to create a tight seal and prevent bacterial movement and its toxins to the periapical tissues. Different approaches and sealants have been developed due to the root canal system's intricacy for ensuring tight adherence. The root canal sealants need to establish a bond between the material and root dentine in order to prevent leakage. Even though the biocompatibility and sealing abilities of the materials are prioritized in modern endodontics, some sealers incorporate therapeutic or antibacterial drugs like corticosteroids or calcium hydroxide. An endodontic sealer's cytotoxicity and antibacterial capabilities must be perfectly balanced. Due to the limited evidence in endodontic literature regarding the relationship between postoperative pain and the sealers that are used in this study, we conducted the research to explore the same. AIM: This study aimed to evaluate and compare pain in responses to polydimethylsiloxane and calcium silicate-based endodontic sealers (CS-BG). METHODOLOGY: The participants were divided into two groups, Nanoseal (Nanoseal-S™; Prevest, DenPro, USA) and Bioceramic (CeraSeal™; Mera Biomed Co., Cheongju, Korea) with 20 patients in each group. After caries excavation and access opening, the biomechanical preparations were performed in each tooth. To avoid over-instrumentation, the working length was verified after each instrument use. The standard irrigation protocol was performed. Sealers were mixed according to the manufacturer's instructions followed by obturation. The patients were asked to take medicines only if they had pain. The pain was evaluated using the visual analog scale (VAS) postoperatively at 24 hours, 48 hours, and a week after the root canal obturation. RESULTS: Pain perception using Nanoseal-S™ and CeraSeal™ materials were compared at 24 hrs, 72 hrs, and seven days. Nanoseal showed statistically significant repletion at 24 hrs and seven days. CONCLUSION: The decreased irritation character of CS-BG for the periapical tissues explains the lesser percentage of pain during and pain immediately after root canal obturation observed in this investigation, which proves CS-BG is highly biocompatible with periapical tissue and further reduces patient anxiety during root canal obturation.

Comparison sealing ability in three bioceramic sealers applied in hydraulic condensation technique by using micro-computed tomography.

Background/purpose: Sealing ability in root canal obturation has always been a key concern for endodontic success. The purpose of this study was to analyze the percentage of voids in root canal space obturated by using single cone hydraulic condensation with different root canal sealers and to compare those with AH Plus sealer. Materials and methods: Experiments were conducted using twenty 3D-printed upper first premolars. After the buccal root canals were prepared using Ni-Ti rotary instruments, the teeth were divided into four groups: the AH Plus, BC sealer, BC sealer HiFlow, and Endoseal MTA groups. All buccal canals were obturated by single-cone hydraulic condensation. All specimens were scanned using micro-computed tomography and the percentage volume of the voids inside and outside the filled materials (Vin and Vout) at three different canal depth intervals were calculated by a Bruker micro-CT software. Differences according to root canal sealers were evaluated statistically using the Kruskal-Wallis test and the Wilcoxon Rank Sum test at a significance level of 0.05. Results: The results indicated that most of the voids were presented near the interface (Vout), the Vin is very small and not significant different between groups. The Vout decreased in the following order: AH Plus(1.837% ± 1.226%)≅BC sealer (1.225% ± 0.836%)>BC sealer Hiflow(0.349% ± 0.071%)>Endoseal MTA(0.203% ± 0.049%). Conclusion: For the percentage volume of voids between the root canal filling material and root canal surface, though the BC sealer Hiflow is slightly larger than Endoseal MTA, which is still much less than BC sealer and AH Plus.

Microleakage Evaluation of Temporary Restorations Used in Endodontic Treatment-An Ex Vivo Study.

(1) Background: Coronal microleakage can lead to endodontic treatment failure. This study aimed to compare the sealing ability of different temporary restorative materials used during endodontic treatment. (2) Methods: Eighty sheep incisors were collected, uniformized in length, and access cavities were performed, except for in the negative control group, where the teeth were left intact. The teeth were divided into six different groups. In the positive control group, the access cavity was made and left empty. In the experimental groups, access cavities were restored with three different temporary materials (IRM®, Ketac™ Silver, and Cavit™) and with a definitive restorative material (Filtek Supreme™). The teeth were submitted to thermocycling, and two and four weeks later, they were infiltrated with 99mTcNaO4, and nuclear medicine imaging was performed. (3) Results: Filtek Supreme™ obtained the lowest infiltration values. Regarding the temporary materials, at two weeks, Ketac™ Silver presented the lowest infiltration, followed by IRM®, whereas Cavit™ presented the highest infiltration. At four weeks, Ketac™ Silver remained with the lowest values, whereas Cavit™ decreased the infiltration, comparable to IRM®. (4) Conclusion: Regarding temporary materials, Ketac™ Silver had the lowest infiltration at 2 and 4 weeks, whereas the highest infiltration was found in the Cavit™ group at two weeks and in the IRM® group at 4 weeks.

Utility of biphasic calcium phosphate cement as a seal for root-end filling.

The recently developed biphasic calcium phosphate cement (BCPC) consists of α-tricalcium phosphate-tetracalcium phosphate as the solid phase and calcium phosphate solution as the liquid phase. BCPC powder is composed of a single solid solution with a monomodal size distribution. Here, we used a bacterial leakage model to examine the utility of BCPC as a seal for root-end filling. We prepared large (median particle size=9.96 µm; BCPC-L) and small (median particle size=4.84 µm; BCPC-S) BCPC powders. In total, 45 single-rooted teeth were instrumented, resected at the root-end, and retrofilled with experimental materials. Mineral trioxide aggregate (MTA) was used as the control. After visual confirmation of BCPC powder size and retrofilling quality by microscopy, bacterial leakage tests were conducted using Enterococcus faecalis. The bacterial leakage tests did not reveal any significant differences between BCPC-S and MTA. Our findings suggest that BCPC-S is useful for root-end filling.

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.

A Spectrophotometric comparative evaluation of the sealing ability of various perforation repair materials with a novel eggshell modified GIC.

Objectives: The objective of this study was to evaluate and compare the sealing ability of mineral trioxide aggregate (MTA), Biodentine, glass ionomer cement, and glass ionomer cement modified with Chicken Eggshell Powder when used as furcation perforation repair material. Materials and Methods: In the present study, 80 human lower first molars were used. Collected teeth had no caries or restoration, and none had fused roots. Every molar had an endodontic access cavity made utilizing a high-speed, long-shank round bur for the initial entry and an Endo-Z for lateral extension and finishing the cavity walls. Each canal's orifice was covered with a temporary filling material. The pulpal floor and cavity walls of every molar were thoroughly coated with two successive coats of clear nail polish. A significant perforation was made between the orifices to the furcation area using a high-speed long shank round bur #4. The perforation centered between the mesial and distal orifice. They were divided into four experimental groups: Group I: 20 molars were repaired using MTA, Group II: 20 molars with Biodentine, Group III: 20 molars were repaired with glass ionomer cement, and Group IV was repaired using glass ionomer cement modified with 7% chicken eggshell powder. Moist cotton pellets were placed over the repair materials, and molars were kept in 100% humidity for 24 h to allow materials to set. Then, according to each group, molars were put in Petri dishes. Methylene blue dye was applied inside the access cavity of all samples for 24 h. Molars were placed under running tap water for 30 min to remove all residues of methylene blue, and then varnish was removed with a Parker blade #15 and polishing discs. Molars were placed in vials containing 1 mL of concentrated (65 wt%) nitric acid for 3 days. Vials were centrifuged at 14,000 rpm for 5 min. The supernatant from each sample was transferred in a quantity of 200 L to a 96-well plate. Sample absorbance was read by an automatic microplate spectrophotometer at 550 nm using concentrated nitric acid as a blank. Statistical analysis was performed using one-way analysis of variance. When the analysis of variance test was significant, the pairwise comparison of the means was done using a Duncan post hoc test. The significance level was set at P < 0.05. Statistical analysis was performed with SPSS 14.0 (SPSS Inc., Chicago, IL, USA) for Windows (Microsoft, Redmond, WA, USA). Results: The highest dye absorbance was seen in Group III, followed by Groups IV, II, and I. Conclusion: Within the limitations of study it was concluded that maximum sealing ability was seen in Biodentine followed by MTA, Glass Ionomer Cement modified with 7% Chicken Eggshell powder and Glass Ionomer Cement.

Sealing ability in vitro study and biocompatibility in vivo animal study of different bioceramic based sealers.

INTRODUCTION: The effectiveness of root canal therapy in endodontic practice is largely determined by providing a compact fluid-tight closure at the apex of the root canal, which inhibits irritant entry and buildup, which leads to a biological breakdown of the attachment mechanism and failure. During obturation, along with gutta-percha, root canal sealers are employed to fill voids and seal root canals. Root canal sealers come in a variety of shapes and sizes, each with its own set. AIM: Evaluation of sealing ability in vitro study by using scanning electron microscopy (SEM) and biocompatibility in vivo animals study of BioRoot RCS and meta Biomed bio_ceramic sealer (CeraSeal RCS) and compared the findings with that of Zinc oxide eugenol (ZOE) sealer as control. MATERIALS AND METHODS: This study utilized two bio_ceramic sealers (BioRoot RCS and meta Biomed bio_ceramic sealer (CeraSeal RCS) and compared the findings with that of ZOE sealer as control. Biocompatibility was determined by examining histopathological biopsy specimens collected from rabbits. Each rabbit had four dentin tubes implanted into the subcutaneous tissues, one for BioRoot RCS, one for CeraSeal RCS, and one for ZOE RCS, with the fourth tube being empty haematoxylin and eosin were used to stain histological sections, and a light microscope was used to evaluate them. Extracted human single canal premolars were used to evaluate the sealing ability. The root canals were divided into three sections (coronal, middle, and apical). SEM was used to assess the adhesion quality at the sealer-dentin interface. RESULTS: BioRoot and CeraSeal sealers have excellent sealing adaptation and biocompatibility, as well as rapid tissue recovery, while ZOE sealers have a slower recovery of inflammatory reaction results when compared to bio_root and ceraSeal sealers, as well as a less sealing adaptation than the two other bio_ceramic sealers. CONCLUSION: In general, the two bioceramic sealers tested were biocompatible and capable of sealing or adhesion. While ZOE had less adherence ability and less biocompatibility.

Comparative Evaluation of Apical Sealing Efficacy of Guttaflow Bioseal, Super-Bond Rc Sealer and Adseal Root Canal Sealer.

Objectives: The objectives of this study is to evaluate apical sealing ability of GuttaFlow Bioseal, Super-Bond RC Sealer, and Adseal root canal sealer. Material and Methods: 36 extracted human single rooted permanent teeth, divided into three groups (n = 12) and obturated by lateral condensation technique. Obturation and root canal sealing was done by either Group I: using GuttaFlow Bioseal, Group II: using Super-Bond RC Sealer and Group III: using Adseal sealer, system. Microleakage was assessed by means of dye penetration method. Results: The dye penetration in Group II was more than in Groups I and III in both vertical and horizontal directions, suggesting that GuttaFlow Bioseal and Adseal sealer are effective in reducing the apical leakage compared to Super-Bond RC Sealer. Conclusion: Bioceramic GuttaFlow Bioseal root canal sealers seal are better root canal sealer but they cannot totally eliminate apical leakage.

Comparative Evaluation of Microleakage of Various Restorative Materials in Pulpotomized Primary Molars - In Vitro Study.

Background and Objectives: Conventionally, stainless steel crown (SSC) is the preferred material for the restoration of pulpotomized primary molars. However, in situations where stainless steel cannot be used necessity for other restorative material arises. Aim: The aim of this study is to assess the microleakage of several coronal seal materials in pulpotomized primary molars- in vitro. Methodology: Seventy-five primary molars were prepared with proximo-occlusal cavities. Restoration was done with Zinc oxide eugenol cement, SSC, composite resin, resin-modified glass-ionomer cement (GIC), and amalgam. Microleakage was assessed using dye penetration technique with stereomicroscope and scanning electron microscope. Statistical Analysis and Results: The Kruskal-Wallis and Mann-Whitney tests were used to statistically analyze the results. Conclusion: With regard to this present study composite resin and resin-modified GIC offers a good alternative for SSC.

Sealing Ability of Obturation with Different Sealers Applied Over Apically Separated Rotary File - Retrograde Bacterial Leakage Study.

Background and Aims: . Retrieval of separated rotary file may not be possible many times. Then sealing of coronal root canal system depends on sealing ability of root canal sealers. The type of seal to be obtained should be bacterial-tight seal. Hence it is important to evaluate the sealing ability of obturation with different newer sealers with separated file in apical 3rd of root canals with bacterial penetration method using e.fecalis. Methods: Forty six human mandibular molars extracted for periodontal reasons were collected. After Decoronation of teeth Protaper rotary S1 files (Dentsply Maillefer) were intentionally separated in apical third of canal and obturated with gutta-percha (Prime Dental Products, India) along with zinc oxide eugenol sealer (Dental products of India-Mumbai) in Group I, Nano Zinc oxide eugenol (Nano Research Lab, Jharkand, India) in Group II and MTA sealer (Angelus, Londrina, Brazil) in Group III. Samples were assessed for bacterial leakage with E fecalis for 48 hours. The number of colony forming units was assessed. Results: The values obtained were subjected to one way ANOVA test and significance level was set to 0.05. Group I scored the highest mean value of (6.58), followed by Group II (3.91). The lowest Mean value was with Group III (2.91). However there was no statistical significant difference in Mean values among groups with (p-value 0.05). Conclusion: The mean value of colony forming units in Group III was 2.91, in Group II 3.91 and 6.58 in Group I. None of the groups demonstrated complete bacteria-tight seal.

Characteristics and seal ability of blend films based on chicken protein isolate and fish skin gelatin.

Blend films from chicken protein isolate (CPI) and fish skin gelatin (FSG) at various CPI/FSG ratios (100:0, 80:20, 70:30, 60:40, 0:100), prepared at pH 3 or 11 were characterized. At the same pH, tensile strength (TS) of CPI/FSG films was higher than CPI and FSG films, and CPI/FSG film (60:40) had highest TS. Moreover, elongation at break (EAB) of blend films increased as FSG content augmented. EAB of CPI film and CPI/FSG (80:20) film was similar for both pHs. CPI films generally possessed higher water vapor permeability (WVP), light barrier property and b*-value than FSG counterpart. CPI films prepared at both pHs were not sealable. Nevertheless, addition of FSG improved sealing ability of blend films. At the same CPI/FSG ratio, seal strength and seal efficiency were lower for films prepared at pH 11. Moreover, higher TS and b*-value were gained, compared to those of films prepared at pH 3. Less cracks on surface and cross-section appeared for CPI/FSG films as revealed by scanning electron microscopy images, compared to CPI and FSG films. Therefore, incorporation of FSG up to 40% into blend film was able to improve mechanical properties, WVP, and sealing ability of blend films.

A novel bioactive glass-based root canal sealer in endodontics.

BACKGROUND/PURPOSE: Bioactive glass (BG), one type of bioceramics, shows similar or better characteristics to calcium silicate which has been regarded as a promising root filling material in endodontics. This study aimed to develop a novel BG-based root canal sealer for endodontics. MATERIALS AND METHODS: The novel BG-based root canal sealer was composed of phytic acid derived bioactive calcium phosphosilicate glass named PSC mixed with zirconium oxide (ZrO2) as powder, and phosphate solution (PS) dissolved with sodium alginate (SA) named PS-SA as liquid. Moreover, the physicochemical properties, mineralization, sealing ability and biocompatibility of the novel BG-based root canal sealer were evaluated. RESULTS: This study developed a novel BG-based sealer named BGS-SA-Zr which contained the powder of PSC and ZrO2 and the liquid of PS-SA. Results indicated that the flow, film thickness and radiopacity of BGS-SA-Zr conformed to ISO 6876:2012. The setting time and solubility of BGS-SA-Zr were 53.7 ±â€¯1.5 min and 21.46 ±â€¯0.54%, respectively. The pH value of the simulated body fluid (SBF) immersed with BGS-SA-Zr raised slightly up to 7.70. The CCK-8 assay indicated that BGS-SA-Zr had no cytotoxic effects on MG-63 cells. After immersion in SBF for 4 weeks, dense hydroxyapatite crystals were observed on the surface of BGS-SA-Zr. Furthermore, there was no difference in the sealing ability between BGS-SA-Zr and the bioceramic sealer iRoot SP whether setting at 1 day or immersed in SBF for 4 weeks (P > 0.05). CONCLUSION: Our results suggest that the novel BG-based sealer may be a promising sealer for endodontic treatment.