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.

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.

Apical Sealing Ability of Calcite-Synthesized Hydroxyapatite as a Filler of Epoxy Resin-Based Root Canal Sealer.

BACKGROUND: The success of root canal treatment is influenced by hermetic root canal obturation. This study was conducted to analyze the apical sealing ability after the addition of calcite-synthesized hydroxyapatite (HA) as an epoxy resin sealer filler. METHODS: Calcite-synthesized HA powder was prepared using the microwave hydrothermal process. HA resin sealer powder and epoxy resin paste (3:1) were mixed, and concentrations of 10%, 20%, 30%, 40%, and 50% were prepared. A sample of thirty maxillary incisors were prepared in the root canal and then, the crown was cut to leave 13 mm of the root and a working length of 12 mm. The root canal was prepared using the crown-down technique and irrigated using 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid alternately. The samples were divided into six groups, with each group consisting of five roots. Group I was obturated with gutta percha using an epoxy resin sealer without HA (HA-0%) as a control group. In each of the Groups II, III, IV, V, and VI, 10% HA resin sealer, 20% HA, 30% HA, 40% HA, and 50% HA were used. All the samples were incubated in a 10-ml simulated body fluid solution at 37°C for 4 weeks. Apical closure density measurement was done using a scanning electron microscope, and the results were analyzed using the Kruskal-Wallis and Mann-Whitney U-tests. RESULTS: A significant increase in the apical sealing ability was observed in the HA-20% sealer group and the HA-30% and HA-40% groups compared to that in the control group. However, the HA-50% sealer group showed a decrease in the apical sealing ability, whereas the HA-10% sealer group showed no difference. The HA-30% had the highest sealing ability than other concentrations. CONCLUSION: The addition of calcite-synthesized HA as a filler at concentrations of 20%, 30%, and 40% increased the apical sealing ability of the epoxy resin sealer.

Comparison of apical sealing ability of bioceramic sealer and epoxy resin-based sealer using the fluid filtration technique and scanning electron microscopy.

BACKGROUND/PURPOSE: A perfect sealing of root canal system is essential for preventing ingress of bacteria from the oral environment. The purpose of this study was to evaluate the apical sealing ability of bioceramic (EndoSequence BC Sealer®) and epoxy resin-based (AH Plus®) sealers at 24 h, 7 days and 4 weeks. MATERIALS AND METHODS: Forty two extracted human upper anterior teeth were sectioned to leave the root 15-mm long, then all the roots were instrumented using a set of ProTaper® rotary instruments. Four roots were selected randomly as controls, and the remaining 38 roots were randomly divided into 2 groups of 19 roots each: group 1: EndoSequence BC Sealer® and gutta-percha, and group 2: AH Plus® and gutta-percha using a multiple wave condensation technique. The apical sealing ability of the filled root canal was measured using the fluid filtration method with 200 mmHg (26.67 KPa) above atmospheric pressure at 24 h, 7 days and 4 weeks. Scanning electron microscopy (SEM) was used to assess the adaptation and penetration of the sealers. The apical microleakage between 2 groups was compared using Student's t-test. P < 0.05 was considered statistically significant. RESULTS: EndoSequence BC Sealer® had significantly better sealing ability than AH Plus® at all test periods (P < 0.001). SEM showed EndoSequence BC Sealer® had better penetration into dentinal tubules. CONCLUSION: Bioceramic sealer could promote proper sealing of root canals obturated with multiple wave condensation.

Comparative Evaluation of Physicochemical Properties and Apical Sealing Ability of a Resin Sealer Modified with Pachymic Acid.

Objective: The addition of pachymic acid (PA) to AH Plus (an epoxy resin sealer) offsets the cytotoxicity of the latter. Prior to the clinical implementation of this formulation, a thorough knowledge of its physicochemical properties and sealing ability becomes mandatory. Hence, this in vitro study aimed to characterize and evaluate the physicochemical properties and apical sealing ability of AH Plus (AHP) with and without the addition of PA. Methods: Flow, setting time, film thickness, solubility and radiopacity of AHP (group 1) and AHP modified with PA (AHP/PA, group 2) were evaluated in accordance with the guidelines put forth by ISO 6876:2012. The percentage was determined under each parameter. Apical sealing ability was assessed using fluid filtration device. An independent samples t-test was used for inter- and intra-group comparisons of mean fluid flow (MFF). Results: Incorporating PA to AHP decreased its flow, setting time and film thickness by 24.34%, 2.14% and 31.71% respectively. The solubility of group 2 increased on day 1 by 85.71% and decreased on days 3, 7 and 14 by 46.67%, 34.79% and 13.8% respectively. The radiopacity of AHP was not altered by the addition of PA. MFF rates of group 2 was significantly higher than group 1 on day 1, but not significantly different on day 7. Conclusion: AHP/PA exhibited physicochemical properties that were within the requirements of ISO and with time, and showed fluid flow similar to AHP.

Comparison of Push-out Bond Strength of Three Different Obturating Systems to Intraradicular Dentin: An In vitro Study.

BACKGROUND: To increase the push-out bond strength of endodontic materials, newer obturation materials and obturation techniques are being introduced. AIM: The present study aimed to evaluate the push-out bond strength of three different obturating materials using a universal testing machine (UTM). MATERIALS AND METHODS: A total of thirty freshly extracted maxillary anterior teeth were collected and randomly divided into three groups of ten each. Biomechanical preparation was done in all the teeth, and they were then divided into three experimental groups according to the obturation material and technique used, as follows: Group I: gutta-percha (GP) with AH Plus root canal sealer (lateral condensation); Group II: thermoplasticized GP technique - noncarrier based (CALAMUS®) with AH Plus sealer (backfill); and Group III: C-points (self-sealing root canal obturating system) with bioceramic sealer (single cone). Each specimen was subjected to push-out test using the UTM, where the punch moved in an apical to coronal direction at a crosshead speed of 0.5 mm/min, which resulted in the displacement of the filling material. The depth of dye penetration was examined under a stereomicroscope at ×30 magnification. RESULTS: All the analyses were performed using SPSS software version 16. P < 0.05 was considered statistically significant. Comparisons of mean values were done using ANOVA with post hoc Games-Howell test and ANOVA with post hoc Tukey's test. Group III demonstrated the highest mean push-out bond strength and Group I exhibited the least bond strength. A statistically significant difference was found between Group III and Group I with regard to the push-out bond strength assessment. CONCLUSION: Push-out bond strength differs among different obturation materials and obturation techniques.

Effect of thermal conductivity on apical sealing ability of 4 dental gutta-percha cones / 北京大学学报(医学版)

Objective:To investigate the effect of thermal conductivity on the apical sealing ability of different dental gutta-percha cones during the warm vertical condensation obturation.Methods:Four kinds of dental gutta-percha cones were used in this study:Bio-GP points (BP,B&L,Korea),large-tapered gutta-percha (DP,DENTSPLY,America),PROTAPER Universal gutta-percha points (DPP,DENTSPLY,America) and mtwo gutta-percha points (VP,VDW,Germany).Volume differences method was used to determine the main components and the thermal conductivity determinator was used to measure the thermal conductivity of these dental gutta-percha cones.Furthermore,20 cones randomly selected from each kind of dental gutta-percha cones.And 10 cones of each dental gutta-percha cones,which were cut out the part of 4 mm in length from the apical end,were heated (200 ℃) from the upper end without compression,and the temperature of the gutta perchacones surface was monitored in time by the infrared thermal imager during the whole heating process.In addition,the rest of the 10 cones of each dental gutta-percha cones were used to obturate the root canal in the transparent root canal resin model using warm vertical condensation technique.The cross-sectional surface was observed by stereomicroscope (× 40) at 1 mm and 3 mm from the working length and the gutta-percha obturation area proportion was measured and analyzed.The data were analyzed by one-way ANOVA.Results:The proportion of inorganic fillers (80.90％ ± 1.14 ％) (P ＜ 0.05) and the thermal conductivity (2.247 ± 0.002)of DP was siguificantly higher than BP (79.28％ ± 3.88％,1.179 ± 0.003),DPP (68.46％ 5.09％,0.604 ±0.001),VP (78.86％ ± 1.87％,1.150 ±0.001) (P ＜0.05).During the thermal obturation without compression at the setting temperature (200 ℃),DP could achieve 65 ℃ beyond 1 mm from the heating point,and BP,DPP and VP only reached 65 ℃ within 1 mm.After warm vertical condensation obturation,all the groups showed increased gutta-percha obturation area proportion.At the position of WL-3,DP (96.89％ ±0.03％) showed significantly higher proportion of gutta-percha obturation area than BP (95.47％ ±0.06％),DPP (95.21％ ±0.03％) and VP (95.15％ ±0.03％) (P ＜ 0.05).Conclusion:DP contains more inorganic fillers,possesses higher thermal conductivity,and leads a better apical sealing ability than BP,DPP and VP at the position of WL-3 during warm vertical condensation obturation.

Apical sealing ability of iRoot SP in oval-root canals in vitro / 实用医学杂志

Objective To evaluate the apical sealing ability of iRoot SP root canal sealer in oval-root canal. Methods After root canals were instrumented by Mtwo, 28 premolars with oval-root canal were randomly divided into 2 groups, 14 teeth in each. The root canals were obturated with AH Plus (group A) and iRoot SP (group B) by modified continuous wave condensation technique. The apical leakage was evaluated by dye penetration method and transparent teeth technique. Results Mean depth of leakage was (0.92 ± 0.26) mm for group A and (0.84 ± 0.40) mm for group B. There was no significant difference between the two groups (t=0.506, P > 0.05). Conclusion The apical sealing ability of iRoot SP is equivalent to AH Plus in oval-root canal.