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.

A novel simplified approach for endodontic retrograde surgery in short single-rooted teeth.

BACKGROUND: High technical thresholds, long operative times, and the need for expensive and specialized equipment impede the widespread adoption of endodontic microsurgery in many developing countries. This study aimed to compare the effects of a simplified, cost-effective, and time-efficient surgical approach involving orthograde obturation using biological ceramic material greater than 6 mm combined with apicoectomy for single-rooted teeth with short lengths with those of the conventional and current standard methods. MATERIALS AND METHODS: Forty-five premolars equally categorized into three groups: conventional surgery group, standard surgery group, and modified surgery group. A µCT scan was used to calculate the volume of voids. A micro-leakage test and scanning electron microscope (SEM) were performed to assess the sealing effect. Additionally, four cases of chronic periapical periodontitis in the anterior region were selected, and the patients received either the modified approach or the standard surgery for endodontic microsurgery. RESULTS: The volumes of voids in the apical 0-3 mm of the modified group and the standard group were comparable. The micro-leakage test and SEM examination demonstrated closely bonded fillings in the dentinal walls in both the modified surgery group and standard surgery group. The outcomes of the preliminary application of this modified procedure on patients were successful at the time of the follow-up cutoff. CONCLUSIONS: The modified surgery group exhibited similar root canal filling and apical sealing abilities with the standard procedure for single-rooted teeth with short lengths (< 20 mm). The preliminary application of this modified surgical procedure achieved favorable results.

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.

The infection control of post-and-core crown restoration.

Post-and-core crown is one of the most common forms of restoration of tooth after root canal therapy (RCT). Infection control is the core objective of RCT, which is usually well realized by endodontists. However, many prosthodontists often neglect the infection control of the tooth and the maintenance of the curative effect of RCT during the process of post-and-core crown, which may lead to the failure of the final restoration. The concept of integrated crown-root treatment advocated recently requires clinicians to consider the RCT and final restoration as a whole, rather than simply divided into two parts-endodontic treatment and restorative treatment. As the core content of integrated crown-root treatment, infection control should be taken seriously by clinicians and implemented throughout the whole treatment process, especially in the restorative treatment that is easily overlooked after RCT. Therefore, this article describes the infection control of post-and-core crown restoration, classifies the tooth requiring post-and-core crown restoration, and puts forward the measures of infection control before and during post-and-core crown restoration, in order to provide reference and guidance for clinical practice.

In vitro evaluation of the sealing ability of combined use of iRoot BP Plus and iRoot SP for root-end filling.

OBJECTIVES: The aim of this in vitro study was to evaluate the sealing ability of combined application of iRoot BP Plus Root Repair Material (BP-RRM) and iRoot SP Injectable Root Canal Sealer (SP-RCS) for root-end filling. MATERIAL AND METHODS: A total of 120 extracted human teeth were used in this study and were randomly divided into four groups. The BP-RRM+SP-RCS group included teeth retro-filled with combined use of BP-RRM and SP-RCS (n=45), and the BP-RRM group included teeth retro-filled by BP-RRM alone (n=45). Teeth without root-end preparation and filling were equally divided into positive control (n=15) and negative control (n=15). The apical sealing ability was evaluated by micro-CT analysis, dye penetrant examination, bacterial leakage test, and glucose leakage test. RESULTS: Micro-CT analysis showed that the total void fraction of BP-RRM+SP-RCS group was significantly lower than that of BP-RRM group, particularly at the coronal 1/3 segment of the retro-filled roots. Consistently, the maximum linear depth of dye leakage in BP-RRM+SP-RCS group was less than that of BP-RRM group. Bacterial leakage test showed that the microbial leakage in BP-RRM+SP-RCS group was significantly less than that in BP-RRM group. However, no significant difference in glucose leakage between BP-RRM+SP-RCS group and BP-RRM group was observed. CONCLUSION: Combined use of BP-RRM and SP-RCS for root-end filling promotes apical sealing in vitro. CLINICAL RELEVANCE: Combined use of BP-RRM and SP-RCS for root-end filling exhibited better apical sealing as compared to BP-RRM alone in vitro, and this may help reducing technical sensitivity and promoting clinical efficiency during endodontic microsurgery.

Analysis of the effects of apical backfilling depth on apical sealing of different root canal filling qualities and morphologies.

PURPOSE: The aim of this study was to evaluate the effects of apical backfilling depth on the apical sealing of different root canal filling qualities and morphologies. METHODS: 3D-printed root canals (A: round, B: oval, C: long oval, D: flat) were used and divided into subgroups by root canal filling quality (a: good, b: poor, c: nonfilling) and backfilling depth (3 mm, 5 mm). A glucose microleakage device was used to measure leakage. RESULTS: (1) 3-mm iRoot BP Plus was filled at the apex, and no obvious leakage occurred in the good root canal filling group, which was significantly smaller than that in the poor/nonfilling groups (P < 0.05). Under good root canal filling conditions in groups A, B, C, and D, no obvious leakage was observed. Under poor/nonfilling root canal filling conditions, there was significant leakage; A and B (P > 0.05) and C and D were compared (P < 0.05). (2) Apical backfilling with 5-mm iRoot BP Plus showed no significant leakage in the poor root canal filling groups with the four morphologies. CONCLUSION: 3-mm iRoot BP Plus was filled at the apex, root canal filling was poor, apical sealing was poor, and root canal morphology affected apical sealing. Apical backfilling with 5-mm iRoot BP Plus improved apical sealing under poor root canal filling conditions, and apical sealing was unaffected by root canal morphology.

Comparison of Apical Sealing Capacity of ActiV GP/Glass Ionomer Sealer Versus Resilon/RealSeal and Gutta Percha/AH plus Sealers.

BACKGROUND: In recent years, concerns have arisen regarding the sealing efficacy of traditional root canal obturation materials such as gutta-percha (GP) and various sealers. The resin-based obturation complexes like RealSealTM (SybronEndo, Orange, CA) and ResilonTM (Resilon Research LLC, Madison, CT) had been developed as replacements for conventional obturation materials, gutta-percha, and various types of sealers. Additionally, ActiV GPTM (Brasseler USA, Savannah, GA), a glass-ionomer-based obturation system, has gained attention. AIM: This in vitro study's objective was to evaluate ActiV GPTM/GI (glass ionomer) sealer's sealing capacity and compare it to that of ResilonTM/RealSeal TM as well as gutta-percha/AH PlusTM (Dentsply International Inc, York, PA) taken as a control. METHODS AND MATERIALS: In this in vitro investigation, 90 freshly excised single-rooted human premolars of the mandible were chosen. According to the substance used to seal the root canals, the teeth were randomly separated into three separate groups (n=30). Group 1: The ActiV GPTM obturation system was used to seal and obturate the canals. Group 2: ResilonTM/RealSealTM was used to obturate and block the canals. Group 3: GP points and AH PlusTM were used to seal the canals employing the lateral condensation methodology. All of the root surfaces-aside from the last 2 mm of the root-were painted with two coats of nail polish before being submerged in 2% methylene blue for a duration of 24 hours at a temperature of 37°C. The highest amount of dye leakage was determined using a stereomicroscope at 20X magnification. RESULTS: The extent of dye penetration at the apical region in specimens of the ActiV GPTM category was 4.93±1.48 mm. The depth of dye penetration at the apical region in specimens of the ResilonTM category was 2.78 ±1.62 mm. The extension of penetration of dye was 0.48± 0.46 mm in specimens of the GP/AH PlusTM category. The degree of microlikeage was maximum in ActiV GPTM specimens and it was minimum in GP/AH PlusTM specimens. The microlikeage in specimens of the Resilon category was greater than GP/AH plusTM while it was lower than ActiV GPTM specimens. The observations were statistically meaningful (p<0.001). CONCLUSION: Based on the results of the dye penetration examination, it can be concluded that the root canal wall sealing capabilities of ActiV GPTM with GI Sealer were inferior to those of GP/AH PlusTM and ResilonTM with RealSealTM.

The infection control of post-and-core crown restoration / 华西口腔医学杂志

Post-and-core crown is one of the most common forms of restoration of tooth after root canal therapy (RCT). Infection control is the core objective of RCT, which is usually well realized by endodontists. However, many prosthodontists often neglect the infection control of the tooth and the maintenance of the curative effect of RCT during the process of post-and-core crown, which may lead to the failure of the final restoration. The concept of integrated crown-root treatment advocated recently requires clinicians to consider the RCT and final restoration as a whole, rather than simply divided into two parts-endodontic treatment and restorative treatment. As the core content of integrated crown-root treatment, infection control should be taken seriously by clinicians and implemented throughout the whole treatment process, especially in the restorative treatment that is easily overlooked after RCT. Therefore, this article describes the infection control of post-and-core crown restoration, classifies the tooth requiring post-and-core crown restoration, and puts forward the measures of infection control before and during post-and-core crown restoration, in order to provide reference and guidance for clinical practice.

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.

An In Vitro Evaluation of Apical Leakage in Gutta-percha/ AH Plus and Resilon/Epiphany-filled Root Canals Using Two Dye Penetration Techniques.

AIM: Aim of the present study was to evaluate the apical leakage in gutta-percha/AH plus and resilon/epiphany filled root canals using two dye penetration techniques. MATERIALS AND METHODS: Sixty freshly extracted human single-rooted teeth were collected. The crown portion of each tooth was sectioned from the cementoenamel junction using a diamond disk. The canals were instrumented using Step back technique up to a caliber of 40. The roots were randomly divided into four experimental groups of 15 sample units each. All the groups are obturated using lateral compaction technique. Samples were placed in India ink and stored in an incubator for 7 days after which they were thoroughly washed under tap water and dried. The roots were divided into longitudinal splitting technique with diamond disks and using clearing technique was checked for linear dye penetration using stereomicroscope. The surfaces were scanned and surfaces with greatest dye penetration were measured by using De winter Biowizard software system. RESULTS: The mean leakage for groups I, II, III, and IV are 2.31980, 2.68140, 4.11567, and 4.21047 respectively. One-way ANOVA was applied to the mean leakage scores of different groups, found a significant difference between mean leakage scores. F value of 3.266 and it was found to be significant with a p value of 0.028. Significant differences were obtained for mean comparisons of groups I and III, groups I and IV and groups III and IV. Further, between groups I and II, groups II and III, and groups III and IV no significant differences were observed. CONCLUSION: In conclusion, gutta-percha/AH Plus sealed root canals showed lesser leakage than the Resilon Epiphany groups and there was no significant difference in the two different methodologies used for dye penetration. CLINICAL SIGNIFICANCE: Tightly adapted endodontic filling material is one of the goals in successful clinical endodontics and Improvements in the adhesive technology have fostered attempts to reduce apical and coronal leakage by bonding to the root canal walls to obtain a solid monoblock.

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.

A comparison of apical sealing ability of different root canal obturation techniques in oval root canals / 口腔疾病防治

Objective@# To investigate the effect of different root canal obturation techniques on apical sealing in oval root canals. @*Methods@#120 recently extracted human premolars with single oval canal were randomly divided into 6 groups, including single point obturation, warm gutta percha vertical condensation, cold lateral condensation obturation method combined with different root canal sealers (iRoot SP or AH-Plus). There're six groups in total, including single point iRoot group, warm gutta percha iRoot group, cold gutta percha iRoot group, single point AH group, warm gutta percha AH group, cold gutta percha AH group. @*Results @#Root depth of dye penetration in warm gutta percha iRoot group and warm gutta percha AH group were significantly lower than group single point iRoot group and single point AH group (P < 0.05), and root depth of dye penetration of warm gutta percha iRoot group, cold gutta percha iRoot group was less than warm gutta percha AH group, cold gutta percha group (P < 0.05), but there was no statistic difference between other groups (P > 0.05). @*Conclusion @#In root canal treatment, warm gutta-percha condensation technology can make the oval canal root achieve better sealing effect, using iRoot SP is better than using AH-Plus.

The effect of semiconductor laser irradiation on root cannal seal / 实用口腔医学杂志

Objective:To evaluate the effect of semiconductor lasers irradiation after routine root canal preparation on root cannal seal.Methods:60 Single-rooted freshly extracted human teeth were randomly divided into 6 groups(n=10).The crowns were removed at the cementoenamel junction and the roots were endodontically prepared with conventional methods.The roots in groups A and B were irradiated with 1 W semiconductor laser for 20 s,in group C and D were ultrasonically washed for 1 min,in group E and F without any treatment were used as the controls.Then all the roots were filled by vertical condensation of warm gutta-percha.The root cannal seal was evaluated with microleakage measurement.The data was analyzed by ANOVA.The teeth of group B,D and F were sectioned and examined under scanning electron microscope(SEM).Results:The microleakage(mm) of group A,C and E was 1.70±0.82,2.02±0.40 and 4.56±2.72 respectively(A vs E,P0.05).SEM observation showed the melting,narrowness or closure of most dentinal tubules in group B,past and/or gutta-percha in the most dentinal tubules of group D.Conclusion:Semiconductor laser irradiation prior to root cannal filling can promote the effects of cannal seal.

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.

Apical Sealing Ability of a Novel Material: Analysis by Fluid Filtration Technique.

AIM: The aim of this study is to evaluate the sealing ability of Biodentine(TM), which is new calcium-silicate based dental cement and has endodontic indications similar to those of MTA. METHODS: The study sample consists of 21extracted human mandibular anterior teeth. The teeth were submitted to root-end preparation and instrumented up to file #40 by step back technique and randomly divided into 3 study groups (n=7): White MTA Angelus(TM) (Angelus, Angelus Odontológica, Londrina, PR, Brazil), Biodentine(TM) (Septodont, SeptodontSpecialités, Saint-MaurdesFosses, France) and the controls. The length of dye penetration between the filling material and tooth structure was measured in millimetres, using a calibrated stereo microscope (Leica MZ75, Germany) at 20× magnification under the same conditions. One-way Analysis of Variance (ANOVA) was used to indicate differences between the experimental groups and the controls. In addition, Tukey Multiple Comparisons Test was used to indicate differences within each group. RESULTS: The results showed that none of the groups were completely sealed. The mean and standard deviation for dye penetration in Biodentine(TM) group was 0.63±0.20 and in MTA Angelus(TM) group, it was 0.26±0.25. Regarding the comparisons between each group, significant differences were not observed (P=0.0193). The comparison between materials only found a significant difference only between MTA Angelus(TM) and Biodentine(TM) (P<0.05). CONCLUSIONS: This study evaluated the possibility of Biodentine(TM)'s sealing ability and marginal adaptation, since no studies are available on Biodentine. However, further in vitro and in vivo investigations should be conducted to determine the suitability of Biodentine(TM) for clinical application.

Avaliação do selamento proporcionado pelo cimento MTA e pasta LC em retro-obturações / Sealing evaluation of mineral trioxide aggregate and pasta LC in retrofilling

Este estudo teve por objetivo avaliar o selamento proporcionado por dois materiais em retro-obturações. Trinta e três dentes humanos permanentes não vivos cujos canais radiculares foram retro-obturados, foram utilizados e divididos aleatoriamente em três grupos iguais, de acordo com o material empregado: G1 = Pasta LC, G2 = MTA e G3 = LC+MTA. As amostras foram impermeabilizadas, imersas em soro fetal bovino por 48 horas e, a seguir, clivados longitudinalmente para medir a infiltração por meio de escores. O resultado dos três grupos foi semelhante depois de submetidoà análise estatística por meio do teste de Kruskal-Wallis.

The purpose of this study was to evaluate the apical sealing of two materials in root-end filling. For this, thirty-three permanent human teeth were root-end prepared divided in three groups randomly, with eleven teeth in each one. The following materials were used: G1 = Pasta LC, G2 = MTA and G3 = LC+MTA. The samples were waterproofed and immersed in fetal bovine serum for 48 hours. After, the roots were separated longitudinally for measuring the infiltration by scores. The results were similar among the groups after submitted to the analysis statistics using the test of Kruskal-Wallis.

Evaluation of canal preparation for apical sealing with various Ni-Ti rotary instruments / 대한치과보존학회지

OBJECTIVES: The aim of this study was to evaluate the various NiTi rotary instruments regarding their ability to provide a circular apical preparation. MATERIALS AND METHODS: 50 single canal roots were selected, cut at the cementodentinal junction and the coronal 1/3 of the canals was flared using Gates Glidden burs. Samples were randomly divided into 5 experimental groups of 10 each. In group I, GT files, Profile 04 and Quantec #9 and #10 files were used. In Group II Lightspeed was used instead of Quantec. In Group III, Orifice shaper, Profile .06 series and Lightspeed were used. In Group IV, Quantec #9 and #10 files were used instead of Lightspeed. In Group V, the GT file and the Profile .04 series were used to prepare the entire canal length. All tooth samples were cut at 1 mm, 3 mm and 5 mm from the apex and were examined under the microscope. RESULTS: Groups II and III (Lightspeed) showed a more circular preparation in the apical 1mm samples than the groups that used Quantec (Group I & IV) or GT files and Profile .04 series.(Group V)(p < 0.05) There was no significant difference statistically among the apical 3, 5 mm samples. In 5 mm samples, most of the samples showed complete circularity and none of them showed irregular shape. CONCLUSIONS: Lightspeed showed circular preparation at apical 1 mm more frequently than other instruments used in this study. However only 35% of samples showed circularity even in the Lightspeed Group which were enlarged 3 ISO size from the initial apical binding file (IAF) size. So it must be considered that enlarging 3 ISO size isn't enough to make round preparation.