ProTaper Rotary Files Research Articles

Effect of diode laser and ultrasonics with and without ethylenediaminetetraacetic acid on smear layer removal from the root canals: A scanning electron microscope study.

Aim:To evaluate the effect of diode laser and ultrasonics with and without ethylenediaminetetraacetic acid (EDTA) on the smear layer removal from root canals.Materials and Methods:A total of 120 mandibular premolars were decoronated to working the length of 12 mm and prepared with protaper rotary files up to size F3. Group A canals irrigated with 1 ml of 3% sodium hypochlorite (NaOCl) followed by 3 ml of 3% NaOCl. Group B canals irrigated with 1 ml of 17% EDTA followed by 3 ml of 3% NaOCl. Group C canals lased with a diode laser. Group D canals were initially irrigated with 0.8 ml of 17% EDTA the remaining 0.2 ml was used to fill the root canals, and diode laser application was done. Group E canals were irrigated with 1 ml distilled water with passive ultrasonic activation, followed by 3 ml of 3% NaOCl. Group F canals were irrigated with 1 ml EDTA with passive ultrasonic activation, followed by 3 ml of 3% NaOCl. Scanning electron microscope examination of canals was done for remaining smear layer at coronal middle and apical third levels.Results:Ultrasonics with EDTA had the least smear layer scores.Conclusion:Diode laser alone performed significantly better than ultrasonics.

Importance of rotary systems in dental care by undergraduate students in patients of a public health service of Belo Horizonte.

BackgroundThe aim of this study was to evaluate the fracture rates of ProTaper rotary files used in the endodontics extension clinic of the Undergraduate Dentistry Course of the Pontifical Catholic University of Minas Gerais during the prior eight years.Material and MethodsControl record data regarding file usage by students were collected and analyzed by semester. For each period, the total number of patient consultations, the frequency of file use, the occurrence of fractures and the file numbers for which fractures occurred were noted. Descriptive statistics, including frequency of file fractures were calculated for all file types. The chi-square test was used to evaluate differences in the frequency of file fractures between all file types.ResultsThe study results revealed that during the examined period, there were 1006 consultations and 7993 uses of files. A total of 30 file fractures were recorded throughout this period; thus, fractures occurred in 0.37% of total file uses and 2.98% of all consultations. The most frequently used files were S1, S2 and F1, and these files also accounted for the most fractures. However, no differences in the frequency of file fractures were observed between the file types (p𰀎0.05).Conclusions The low fracture rates observed in this study indicate that the examined instruments can be used to safely provide dental care to patients. Key words:Dental instruments, endodontics, public health.

An Evaluation of Apical Cracks in Teeth Undergoing Orthograde Root Canal Instrumentation

IntroductionDentinal damage and cracks induced by orthograde preparation methods have been reported in studies using extracted teeth. The purpose of this in situ investigation was to evaluate dentinal cracks in nonextracted teeth after final instrumentation. The null hypothesis is that orthograde root canal instrumentation will have no effect on crack initiation in teeth retained in the natural periodontium. MethodsMandibular first and second premolars of pig jaws were selected. Forty single-rooted canals were divided into 5 groups (n = 8):(1) WaveOne (Dentsply Tulsa Dental Specialties, Tulsa, OK) 25/08;(2) ProTaper rotary S1, S2, F2 (25/08) (Dentsply Tulsa Dental Specialties);(3) crown-down GT hand files 20/12, 20/10, 20/08 (Dentsply Tulsa Dental Specialties);(4) positive control (purposefully cracked); and(5) negative control (uninstrumented teeth). After instrumentation, superficial soft tissue was removed, and bone was carefully peeled away with surgical burs to the level of the root apices. Roots were resected 1 mm coronal to the working length, stained with caries indicator dye, and transilluminated; images were captured and viewed at 30× magnification to determine the presence or absence of dentinal cracks. ResultsWaveOne, ProTaper rotary, and GT hand files produced no cracks. All positive controls had cracks; all negative controls had no cracks. ConclusionsWithin the limits of this investigation, the presence of natural periodontal structures may prevent cracking or dentinal damage in teeth receiving orthograde root canal instrumentation.

Satisfaction of undergraduate students at University of Jordan after root canal treatment of posterior teeth using rotary or hand preparation.

The aim of this study was to report the satisfaction of fifth year undergraduate students on the clinical use of rotary endodontic preparation compared with stainless steel standard technique and to evaluate the impact of rotary nickel-titanium instruments on undergraduate teaching. This study was carried out by the fifth year undergraduate students attending peer review sessions as a part of their training program using a questionnaire to assess their satisfaction with these two techniques. The overall results indicated a statistically significant satisfaction of the undergraduate students with the use of the nickel-titanium system (P < 0.001) compared to stainless steel standard technique. Under the conditions of this study, the results showed a positive acceptance and consensus among novice dental students regarding the use of ProTaper rotary files and the need for undergraduate teaching of rotary nickel-titanium systems in Jordan.

Effects of different instrumentation techniques on calcium hydroxide removal from simulated immature teeth.

The aim of this study was to evaluate the effectiveness of endodontic instrument systems in the removal of calcium hydroxide [Ca(OH)(2)] from simulated immature teeth. The root canals of 106 human single-rooted teeth were shaped with ProTaper rotary files up to an F5 file size. Simulation of roots with immature apices was carried out using size 4 green 1.5-mm diameter Unicore drills. A non-setting Ca(OH)(2) was injected into each root canal and inserted into the working length using lentulo spiral, after which cotton pellets were placed over canal orifices. The apical and coronal side of the roots were then sealed with glass ionomer cement and light cured. Specimens were stored in distilled water for 3 months at 37 °C. After 3 months, the temporary coronal seal was removed and the samples were randomly divided into five experimental groups according to the method used for Ca(OH)(2) removal (ProTaper, Reciproc, OneShape, WaveOne, and Manual) (n = 20), one positive control group (n = 3) and one negative control group (n = 3). The amount of remaining Ca(OH)(2) in the canal walls was measured under a stereomicroscope at 30× magnification. The data were analyzed using Kruskal-Wallis test and Mann-Whitney U test at a significance level of 0.05. Positive and negative control groups were found to be statistically different from all other groups (p < 0.05). There were no significant differences among the ProTaper, Reciproc, OneShape, WaveOne, and Manual groups (p > 0.05). As a conclusion, none of the techniques completely removed Ca(OH)(2) from simulated immature teeth.

Comparison of Different Irrigation Activation Regimens and Conventional Irrigation Techniques for the Removal of Modified Triple Antibiotic Paste from Root Canals

IntroductionThe aim of this study was to compare the efficacy of irrigation activation regimens and conventional syringe irrigation technique in the removal of modified triple antibiotic paste (mTAP) from root canal walls. MethodsFifty-six extracted human mandibular premolars were prepared using ProTaper rotary files (Dentsply Maillefer, Ballaigues, Switzerland) up to size F4. The root canals were filled with mTAP medicament, and after 21 days, the roots were randomly assigned to 5 groups (n = 10) according to the irrigation regimens used: conventional syringe irrigation (CI), Self-Adjusting File (SAF; ReDent-Nova, Ra'anana, Israel), EndoVac (Discus Dental, Culver City, CA), EndoActivator (Dentsply, Tulsa, OK), and passive ultrasonic irrigation (PUI). In 3 teeth, mTAP was not removed (positive controls), and another 3 teeth were not filled with mTAP (negative controls). The roots were sectioned, and the amount of remaining medicament at each root half (n = 20) was evaluated at 30× magnification using a 4-grade scoring system. Data were evaluated using the Kruskal-Wallis and Mann-Whitney U tests. ResultsThere were statistically significant differences among all experimental groups; of which, the CI group was the significantly least efficient in removing mTAP from the root canal (P < .05). At the apical and middle third, the PUI, SAF, EndoVac, and EndoActivator groups removed significantly more mTAP medicament than the CI group (P < .05); however, there were no significant differences between these groups (P > .05). The SAF and PUI showed significantly better performances in removing mTAP from the coronal third (P < .05). ConclusionsThe use of irrigation activation regimens significantly improves the removal of mTAP from root canals when compared with CI.

Efficacy of MTAD with shortened irrigation time on smear layer removal after rotary canal instrumentation: An in vitro study

Context: A search in the endodontic literature showed the absence of any reports regarding the use of a mixture of tetracycline, acid, and detergent (MTAD) to remove smear layer at shortened irrigation time. Aims: To determine the efficacy of MTAD with shortened irrigation time on smear layer removal after Pro Taper rotary canal instrumentation. Methods: Twenty single-rooted lower premolar teeth were randomly divided into two experimental groups. After decoronation of all the samples, working length was determined and all the teeth were instrumented to master apical size # 30 (F3), using Pro Taper rotary files. Teeth were irrigated with 3% NaOCl during instrumentation. Experimental groups one and two were irrigated with a 5 ml final rinse using MTAD for 5 min and 2.5 min, respectively. After irrigation, all root canals were dried with absorbent paper points. The teeth were then sectioned longitudinally and prepared for a scanning electron microscopic examination. The scanning electron microscope photographs were evaluated using a standard scoring system developed by Rome et al . Statistical Analysis Used: Results were statistically analyzed using Mann–Whitney U-test. Results: When intercomparison was made between Group 1 and 2 at the coronal and middle third, statistically significant difference was observed, with Group 1 having significantly less smear layer than Group 2. In apical third, no statistically significant difference was observed between Group 1 and 2, even though smear layer removal was more in Group 1 than Group 2. Conclusion: Effective smear layer removal was not possible with shortened irrigation time using MTAD.

Effectiveness of different irrigation protocols on calcium hydroxide removal from simulated immature teeth after apexification

Aim: To evaluate the effectiveness of different irrigation solutions and ultrasonic activation of the irrigation solutions on the removal of calcium hydroxide (Ca(OH)2) from the simulated immature root canals after apexification.Materials and methods: One-hundred and one single-rooted teeth were used. The root canals were shaped with ProTaper rotary files up to F5. Simulation of roots with immature apices was carried out using size 4 Unicore drills. An injectable Ca(OH)2 was injected into each root canal, and packed to the working length. Then, cotton pellets were placed over canal orifices, and apical and coronal parts of the roots were sealed with resin-modified glass ionomer cement, and light cured. Specimens were stored in distilled water for 3 months at 37°C. After 3 months, the temporary coronal seal was removed and the samples were randomly divided into: (a) saline (n = 20), (b) ultrasonic activation of saline (n = 20), (c) sodium hypochlorite (NaOCl) (n = 20), (d) ultrasonic activation of NaOCl (n = 15), (e) chlorhexidine digluconate (CHX) (n = 20) and one positive control group (n = 3) and one negative control group (n = 3). The amount of remaining Ca(OH)2 on the canal walls was measured under stereomicroscope with 30× magnification. Comparisons between groups were made by the non-parametric Kruskal-Wallis test and Dunn post-test at a significance level of p < 0.05.Results: There were no significant differences among the saline, ultrasonic activation of saline, NaOCl, ultrasonic activation of NaOCl and CHX (p > 0.05) groups.Conclusions: Irrigation solutions and ultrasonic activation of the irrigation solutions could not completely remove Ca(OH)2 from the simulated immature root canals.

A Comparative SEM Investigation of Smear Layer Remaining on Dentinal Walls by Three Rotary NiTi Files with Different Cross Sectional Designs in Moderately Curved Canals

The objective of this study was to compare the smear layer formed on root canal walls during canal preparation of extracted human teeth by Twisted, Mtwo, and ProTaper rotary nickel titanium instruments. Sixty single rooted human premolar teeth with root curvature <25(0) were selected and randomly divided into three Groups (n= 20 teeth per Group). Three types of rotary nickel titanium instruments were used, Twisted (SybronEndo, Orange, CA, USA), Mtwo (VDW, Munich, Germany) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) according to manufacturer's instructions to instrument the root canals. Irrigation for all groups was performed after each instrument change with 3ml of 3% sodium hypochlorite followed by Glyde (File Prep, Dentsply, Maillefer, Ballaigues, Switzerland) as chelator paste and lubricant. Three different areas (coronal, middle and apical thirds) of the root canal were evaluated using scanning electron microscopy (SEM). The canal wall of each sample was assessed and compared using a predefined scale for the presence or absence of smear layer. Data were analysed statistically using ANOVA and Tukey HSD test Results: All three groups showed statistically significant more smear layer in the apical thirds of the canal as compared to the coronal and middle thirds (p<0.001). Mtwo rotary file system produced significantly less smear layer (p<0.001) compared to Twisted and ProTaper rotary instruments in the apical portion. Twisted Files resulted in less smear layer formation in the apical thirds of the canal compared to ProTaper rotary instruments but were statistically insignificant. Completely clean root canals were not found after instrumentation with any of the three instruments. Under the confines of this study Mtwo instruments produced significantly cleaner dentin wall surfaces throughout the canal length in comparison to Twisted and ProTaper rotary files. Twisted Files proved to be comparable to ProTaper rotary instruments with respect to canal cleanliness in the apical thirds of the root canal.

Comparative evaluation of efficacy of EndoVac irrigation system to Max-I probe in removing smear layer in apical 1 mm and 3 mm of root canal: An in vitro scanning electron microscope study.

The purpose of this study was to compare the efficacy of EndoVac irrigation system and side-vented closed ended needle (Max-I probe) in removing smear layer from root canals at 1 mm and 3 mm from working length using ProTaper rotary instrumentation. A total of 50 freshly extracted maxillary central incisors were randomly divided into two groups after complete cleaning and shaping with ProTaper rotary files. In one group, final irrigation was performed with EndoVac system while in other group, final irrigation was done with a 30 gauge Max-I probe. 3% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetracetic acid were used as final irrigants in all teeth. During instrumentation, 1 ml of 3% NaOCl was used for irrigation after each rotary instrument in the similar manner as in final irrigation. After instrumentation and irrigation, teeth were sectioned longitudinally into buccal and palatal halves and viewed under scanning electron microscope for evaluation of smear layer. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U-test. (P < 0.05). At 3 mm level, there was no significant difference between two groups. At 1 mm level, EndoVac group showed significantly better smear layer removal compared with Max-I probe (P = 0.0001). EndoVac system results in better smear layer removal at 1 mm from working length when compared to Max-I probe irrigation.

Comparison of Push-out Bond Strength of Gutta-percha to Root Canal Dentin in Single-cone and Cold Lateral Compaction Techniques with AH Plus Sealer in Mandibular Premolars.

Background and aims. The single-cone technique has gained some popularity in some European countries. The aim of the present study was to compare the push-out bond strength of gutta-percha to root canal dentin with the single-cone and cold lateral compaction canal obturation techniques.Materials and methods. The root canals of 58 human mandibular premolars were prepared using modified crown-down technique with ProTaper rotary files up to #F3as a master apical file (MAF) and divided randomly into groups A and B based on canal obturation technique. In group A (n = 29) the root canals were obturated with single-cone technique with #F3(30/.09) ProTaper gutta-percha, which was matched with MAF in relation to diameter, taper and manufacturer; in group B (n = 29) the canals were obturated with gutta-percha using cold lateral compaction technique. In both groups AH plus sealer were used. After two weeks of incubation, three 2-mm slices were prepared at a distance of 2 mm from the coronal surface and push-out test was carried out. Data were analyzed with descriptive statistics using independent samples t-test.Results. There were statistically significant differences between two groups. The mean push-out bond strength was higher in group B (lateral compaction technique) compared to group A (single-cone technique; P < 0.05).Conclusion. Use of single-cone technique for obturation of root canals resulted in a lower bond strength compared to cold lateral compaction technique.

Analysis of marginal seal of ProRoot MTA, MTA Angelus biodentine, and glass ionomer cement as root-end filling materials: An in vitro study

Background: Search for a root-end filling material fulfilling all the ideal characteristics is an ongoing process. The present study aimed to evaluate the marginal seal of the following materials when used as root-end filling materials, MTA Angelus, White ProRoot MTA, Biodentine and Glass ionomer cement (GIC). Materials and Methods: Sixty single-rooted maxillary central incisors were included in the study. The crowns were resected followed by cleaning and shaping with hand files and protaper rotary files followed by obturation of the roots. The root ends were resected at 3 mm level. Then, root-end cavity preparation of 3 mm depth was done using ultrasonic tips. The samples were randomly divided into four groups of 15 each and cavities restored with, such as (1) Group 1: MTA Angelus, (2) Group 2: ProRoot MTA, (3) Group 3: Biodentine, and (4) Group 4: GIC. The root samples were coated with two coats of nail varnish and immersed in methylene blue dye 2% for 48 h. Longitudinal root resection was done. The depth of dye penetration was evaluated under the stereomicroscope to examine the extent of microleakage. The amount of dye penetration was measured in millimeters. The results were then statistically analyzed using one-way analysis of variance and post-hoc Tukey's test. Conclusion: Microleakage was present in all the samples. Least amount of apical dye microleakage was seen in biodentine with mean value of 0.16 mm followed by ProRoot MTA 0.68 mm, MTA Angelus 0.74 mm, and GIC 1.53 mm. The best sealing ability was seen in biodentine, and this difference was statistically significant.

Antibacterial and smear layer removal capability of oregano extract solution.

Objective:The aim of this in vitro study was to evaluate the antimicrobial effect of oregano extract solution (OES) against Enterococcus faecalis within root canals and dentin tubules, and its effect on smear layer.Materials and Methods:A total of 180 human maxillary central incisors was selected. After removal of coronal part of the teeth, root canals were prepared using ProTaper rotary files (Dentsply, Tulsa Endodontics, OK, USA) to #F3 with the crown-down manner. The roots were randomly assigned to 15 groups (n = 12 for each). In the first seven groups, the antimicrobial effects of the test groups were evaluated. Suspensions of E. faecalis cultures were adjusted to 1.0 McFarland (1 × 108 colony-forming unit [CFU]/ml), and sterilized teeth were placed in Eppendorf tubes and kept at 37°C for 4 weeks. Samples were then taken from the root canals before irrigation using three sterile paper points. Dentin samples were taken from root canals with ProTaper #F4 and #F5 series rotary instruments after irrigation. The aliquots of samples were placed into the brain heart infusion and incubated at 37°C for 48 h and then the CFUs were counted. In the other eight groups, the efficacy of the irrigation solutions on removing the smear layer was evaluated using scanning electron microscope (Leo 440, Oxford Microscopy Ltd., Cambridge, England) analysis. Statistical evaluation of the microbiological data was performed using the Kruskall–Wallis and Mann–Witney U-test (P < 0.05).Results:There was a statistically difference between the groups (P < 0.05). Chlorhexidine gluconate (CHX), 5% and 2% OES wasn’t found to be statistically significant regarding their antibacterial activities against E. faecalis (P > 0.05). 1% OES and NaOCl showed similar antimicrobial effect (P > 0.05), and 1% OES and NaOCl were better than ethylenediaminetetraacetic acid (EDTA) and saline (P < 0.05) but not as successful as CHX. According to the results obtained from dentin, CHX is the most effective solution within dentinal tubules. Different concentrations of OES were not achieved smear layer removal alone but OES in conjunction with 17% EDTA was the final irrigating solution achieved the smear layer removal without dentin erosion.Conclusions:Within the limitations of this study, OES appears to be a possible alternative to NaOCl as a root canal irrigant on the eradication of E. faecalis and removal of smear layer.

Evaluation of effect of addition of 2% chlorhexidine on the sealing ability of Biodentine: An in vitro study.

Aim:To evaluate the effect of the addition of 2% chlorhexidine on the sealing ability of Biodentine.Materials and Methods:Forty-six extracted human premolar teeth with single canal and apical foramen were selected, cleaned, and decoronated to standardize the length of 17 mm. Canals were prepared using ProTaper rotary files till size F4. The samples were divided into 2 experimental groups of 20 samples each on the basis of absence/presence of 2% chlorhexidine in liquid: Group BM = Biodentine mixed with the provided liquid, Group BC = Biodentine mixed with 2% chlorhexidine in provided liquid. Three samples, each were assigned to control groups: Group BP (positive control) = No root end filling was placed, Group BN (negative control) = Root ends were filled as in Group BM, and entire external surface was coated with sticky wax. The samples were then evaluated for the apical sealing using fluid filtration method.Results:Results were analyzed using Student's t-test (P ≤ 0.05). Group BC showed the better sealing ability (3.06) as compared to Group BM (3.85). However, the difference was statistically insignificant (P > 0.05).Conclusion:Addition of 2% chlorhexidine to the liquid enhanced the sealing ability of Biodentine.

Sealing ability of a novel hydrophilic vs. conventional hydrophobic obturation systems: A bacterial leakage study.

Aim:Comparative assessment of apical sealing ability of a novel Smart-Seal System, Resilon, and conventional Gutta-Percha system using a bacterial leakage model.Materials and Methods:Seventy freshly extracted human single rooted teeth with fully formed apices were randomly divided into three groups (20 each) and two control groups (5 positive and 5 negative). Teeth were de-coronated, and roots were standardized to a working length of 16 mm. Root canal preparation was done with rotary pro-taper file system in all groups. Group A was obturated using Smart-Seal system (Hydrophilic), Group B using Resilon/Epiphany system (Hydrophilic), and Group C using Gutta-Percha (GP)/AH plus system (Hydrophobic) in a single cone technique. Using Enterococcus faecalis, a split chamber bacterial leakage model was developed to evaluate the sealing ability of three obturation systems. Samples will be monitored every 24 hours for 60 days.Results:All three groups have shown leakage. Novel Smart-Seal System and Resilon have shown similar results and relatively lesser samples leaked in comparison to GP obturations at the end of the observation period. There was no significant difference amongst Resilon and Smart-Seal System (P > 0.05) but there was a significant difference amongst them when compared to GP obturations (P < 0.05).Conclusion:Hydrophilic obturations of the root canal shows a better resistance to bacterial leakage as compared to hydrophobic obturations.

Temperature Profiles Along the Root with Gutta-percha Warmed through Different Heat Sources.

Objectives: To evaluate temperature profiles developing in the root during warm compaction of gutta-percha with the heat sources System B and System MB Obtura (Analityc Technology, Redmond, WA, USA). Thirty extracted human incisor teeth were used. Root canals were cleaned and shaped by means of Protaper rotary files (Dentsply-Maillefer, Belgium), and imaging was performed by micro-CT (Skyscan 1072, Aartselaar, Belgium). Methods: Teeth were instrumented with K-type thermocouples, and the roots were filled with thermoplastic gutta-percha. Vertical compaction was achieved through the heat sources System B and System MB, and temperature profiles were detect-ed by means of NI Dac Interface controlled by the LabView System. With both heat sources, higher temperature levels were recorded in the region of the root far from the apex. When the warm plugger tip was positioned at a distance of 3 mm from the root apex, temperature levels of about 180°C were used to soften gutta-percha, and no statistically significant differences were observed between peak temperatures developed by the two heating sources at the root apex. However, a temperature level higher than 40°C was maintained for a longer time with System MB. Results: Statistically significant differences were observed in peak temperature levels recorded far from the root apex. Thus, with a temperature of about 180°C and the warm plugger positioned at 3 mm from the root apex, both heating sources led to a temperature slightly higher than 40°C at the apex of the root, suggesting that the gutta-percha was properly softened. Significance: A temperature level higher than 40°C was maintained for a longer time with System MB, thus providing an ad-equate time for warm compaction of the gutta-percha.

Assessment of calcium ions diffusion and pH measurements of three intracanal medicaments through dentinal tubules (in vitro comparative study)

Objectives: The purpose of this study was to evaluate the release of Calcium ions from three intracanal medicaments [Ca(OH)2 , White Proroot MTA , Biodentine], and to measure the PH of these three materials. Materials and Methods: Forty-two single rooted permanent teeth were prepared using crown down technique with Protaper rotary files to a master apical file size 40. The canals were irrigated by using 2 ml 5.25% NaOCl for 60 seconds after each instrument change, final irrigation of canals using 5 ml of 17% EDTA for 3 minutes and 5 ml of 5.25% NaOCl for 60 seconds and finally 10 ml of saline solution. The canals were dried and the intracanal medicaments were applied according to manufacturer instruction after setting of materials, both apical and coronal openings were sealed by Cavit and a layer of Epoxy resin on it. Each root was immersed in 30 ml of deionized water. The digital pH meter was used for measuring the pH values for each root 10 times per each studied period (1, 2, 7, 15, 30, 45, 60) days; The Calcium ions release measurements were taken for each studied periods using Atomic Absorption Spectrophotometer device. The results were analyzed statistically using ANOVA (F test), a p-value &lt; 0.05 was considered as a significant. Results: The pH values for Ca (OH)2 and PMTA groups were gradually increased and need more time for increasing than the Biodentine. The pH values for Biodentine were the highest at the first day then decreased in the 2nd and 7th days, then increased over time until sixty days. The calcium ions release values were gradually increase for three medicament and its values were highest for Biodentine followed by Ca(OH)2 and finally PMTA. The differences between groups were statistically highly significant. Conclusions: Biodentine exhibited highest mean values in the calcium ions release and pH measurements than other groups and PMTA showed lowest mean values in the calcium ion release and pH measurement.

Comparative assessment of apical sealing ability of three different endodontic sealers: A scanning electron microscopic study

AimThe present in vitro SEM study compared the apical sealing ability of three different endodontic sealers used in single cone obturation technique. Material and method45 freshly extracted mandibular premolars with single canal and fully formed apices were selected. The samples were decoronated at/below the cementoenamel junction (CEJ) obtaining root lengths of 15 mm. The samples were instrumented using ProTaper rotary file system SX-F2. Following instrumentation the samples were randomly divided in three different groups for three different sealers to be used in single cone obturation technique. Group 1 EndoSequence BC, Group 2 GuttaFlow 2 and Group 3 AH Plus. The sealers were allowed to set completely. Following this the samples were longitudinally sectioned at the apical third and gold sputtered for SEM evaluation. The interphase between the radicular dentin and the root canal filling material were obtained in micrometers (μm) from the SEM images. Statistical analysis was performed. ResultsThe groups exhibited a statistically significant difference (p < 0.01). Group 3 presented with the highest interphase distance (p < 0.01), whereas Group 1 and 2 exhibited a statistically similar values (p > 0.05). ConclusionThe GuttaFlow 2 and Endosequence BC endodontic sealers showed better adaptation to the radicular dentin as compared to AH Plus sealer.

Fracture Resistance of Resilon-Filled Roots Following Different Retreatment Techniques

The aim of this study was to investigate whether endodontically retreated teeth filled with Resilon are more resistant to fracture than those filled with guttapercha following hand or rotary removal techniques. Seventy-two upper anterior human teeth were selected, decoronated and reduced to 12 mm. The canals were shaped using rotary ProTaper files and randomly assigned into two groups (n=36). Obturation was performed using guttapercha/AH-Plus in Group 1 and Resilon/RealSeal in Group 2. The roots were stored for one week at 37°C. The roots were then randomly allocated into three subgroups: A (n=10), no further treatment was performed. In B (n=13), the filling was removed using hand K-files and in C (n=13) using ProTaper retreatment files. Subgroups B and C were refilled using the same materials as used in the primary treatment and stored for one week. Three roots from each of the four subgroups were left unfilled to act as a control (n=12). All the roots were embedded in resin and subjected to fracture in a universal testing machine. Data were analysed using Kruskal-Wallis with multiple pairwise comparisons. Resilon-refilled roots showed no significance difference in fracture resistance compared with guttapercha-refilled roots regardless of the retreatment technique. There was no significant difference in fracture resistance between the two retreatment techniques. When used as a root filling material, Resilon was found not to increase the fracture resistance of primarily and previously root filled teeth regardless of the retreatment technique.

An Evaluation of the Apical Seal in Oval-shaped Root Canals Prepared with Either Self-adjusting Files or ProTaper Files

Normal 0 21 false false false TR X-NONE X-NONE Objective: This study aimed to evaluate the apical seal obtained with lateral compaction of gutta-percha in oval-shaped root canals prepared with either self-adjusting files or ProTaper rotary files. Materials and Methods: Twelve pairs of extracted mandibular premolars with oval-shaped root canals were randomly divided into two groups. The first group was biomechanically prepared with ProTaper files, while the self-adjusting file system was used in the second group. The roots were obturated using cold lateral compaction of gutta-percha. Apical microleakage was measured with the computerized fluid filtration method. The results were analyzed statistically using the Mann-Whitney U test. Results: All of the roots in both groups showed leakage. Group 1 demonstrated significantly less microleakage ( p < 0.05) . Conclusions: Instrumentation of oval-shaped canals using a self-adjusting file system with cold lateral compaction of gutta-percha demonstrated significantly greater apical microleakage when compared to ProTaper. The apical leakage with different obturation techniques, combined with self-adjusting files, should be evaluated in further studies.