Master Apical File Research Articles

Effectiveness of Chloroform and Orange Oil as Gutta-percha Solvents used in Endodontic Retreatment: An In Vitro Study

The aim of this study was to assess and compare the effectiveness of chloroform and orange oil to dissolve obturated materials during endodontic retreatment. Thirty extracted human permanent maxillary anterior teeth (10 central incisor, 10 lateral incisor and 10 canine) which fulfilled specific inclusion criteria were de-coronated and after biomechanical preparation using step-back technique obturated with gutta-percha and AH plus sealer and stored in 370C in 100% humidity for 2 weeks. Then the teeth were assigned into 2 groups randomly: Chloroform (n= 15) and Orange oil (n= 15). Solvents were applied to reservoir created on the coronal root third for 2 minutes. Then instrumentation was initiated to remove obturated materials using Hedstrom file until the master apical file size 40 for central incisor and canine and 35 for lateral incisor reach the working length. The time to reach the working length and the time to obtain the last debris were recorded. Data were collected and analyzed by using SPSS version 22. The results showed no statistically significant difference (P>0.05) between two gutta-percha solvent groups in relation to time required to reach the working length by master apical file and time required to remove total obturated material from root canal. In conclusion, there was no statistically significant difference in effectiveness between chloroform and orange oil as gutta-percha solvent during retreatment procedure. So, orange oil can be used in retreatment procedure with the same efficacy of chloroform to dissolve obturated material in the root canal.

Effectiveness of mechanical vs. chemomechanical methods in removing intracanal calcium hydroxide medication: a randomised trial.

To compare the mechanical and chemomechanical methods for removing calcium hydroxide medication from the root canal system. The triple-blind, randomised clinical trial was conducted at the Department of Operative Dentistry and Endodontics, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan, from December 16, 2022, to June 15, 2023, and comprised patients having necrotic teeth and chronic apical pathosis. They were randomised into groups A and B. On the initial visit, after access opening and chemomechanical preparation, calcium hydroxide paste was placed as an intracanal medication in both groups. the patients were recalled after two weeks. In Group A, calcium hydroxide was removed from the canals using a rotary master apical file, while in Group B, an endoactivator was used to sonically agitate the endodontic irrigant. Verification of placement was done by using a periapical radiograph. Data was analysed using SPSS 26. Of the 98 individuals assessed initially, 60(61.22%) were included; 34(57%) females and 26(43%) males with age ranging from 19 to 57 years. There were 27(45%) incisors, 22(36.7%) premolars and 11(18.3%) canines. There were 30(50%) patients in each of the 2 groups. The intergroup difference was not statistically significant (p=0.43). Tooth arch did not significantly correlate with the removal method (p=0.79). Both methods were found to be equally effective in removing water-based calcium hydroxide medication from the endodontic system. NCT05744661.

Effect of apical foraminal enlargement on postoperative pain and inflammatory markers in asymtomatic single-rooted mandibular teeth with apical periodontitis - An in vivo randomized controlled trial.

This study aims to assess the effect of apical foraminal enlargement on inflammatory markers and pain in patients with asymptomatic single-rooted mandibular teeth with apical periodontitis. The study included 60 patients based on inclusion and exclusion criteria. Before beginning root canal treatment (RCT), a blood sample was obtained from the antecubital fossa to evaluate the inflammatory markers, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Access opening was done and initial irrigation was done. Working length (WL) was determined with an electronic apex locator and verified with a radiograph. In the control group, the determined WL was maintained, while in the experimental group, the WL was set till the apical foramen. Biomechanical preparation was done in both groups till F2 or F3 based on the initial apical file, followed by final irrigation and obturation based on the master apical file size. Patients were given a Visual Analog Scale to record pain sensations at 24, 48, and 72 h postoperative. After 72 h, patients were recalled for follow-up appointments, and blood was taken from the antecubital fossa again to evaluate inflammatory markers. The resultant findings for the reduction in inflammatory markers before and after RCT with or without foraminal enlargement were statistically analyzed using the Student's t-test. The pain was statistically examined with one-way "analysis of variance" and Tukey's post hoc test for inter-group comparison of pain. The level of significance was set at P < 0.05. The statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) Version 23 for Windows (SPSS Inc., Chicago, IL, USA). As pain in the control groups is zero before and after RCT, statistical analysis is not required as the overall pain score is zero. The P values of the CRP and ESR of the control group were 0.02 and 0.03, respectively, which indicates it is significant whereas the P values of the ESR and CRP of the experimental group were 0.0002 and 0.0008 which indicates it is highly significant. Results indicate that the experimental group is more effective compared to the control group in reducing inflammatory markers. Pain in the control group after RCT was zero at the end of 24, 48, and 72 h. In the experimental group, where RCT was done with apical foraminal enlargement, mild pain was present at the end of 24 h which gradually decreased at the end of 48 h and no pain was reported at the end of 72 h. Reduction in inflammatory markers was more effective in RCT with apical enlargement than without apical enlargement. RCT with apical enlargement caused mild pain in the patients immediately after treatment which gradually decreased over time.

Outcomes of root canal treatments with three different sealers for 120 fractured maxillary fourth premolar teeth in small-to medium-sized dogs.

Tooth fracture is one of the most common traumatic maxillofacial injuries in dogs and cats. For fractures with pulp exposure occurring in functionally important teeth, the literature indicates that root canal treatment (RCT) is an effective therapy option that may be the remedy of choice before extraction. The most commonly reported fractures in the United States involve canine teeth; however, fractures of the maxillary fourth premolars are more common in Korea, where there are many small-and medium-sized dogs. RCT mechanically and chemically removes pulp tissue and bacteria (cleaning and shaping) from the infected root canal, and obturates the root canal with filling material to restore tooth functionality without inflammation. Various techniques, instruments, and materials used in humans have been modified for application in veterinary dentistry. This study analyzed the results of RCT of the maxillary fourth premolar in 120 small-and medium-sized dogs (weighing less than 25 kg) using three different sealers (silicone-based sealer, bioceramic sealer, and calcium hydroxide-based sealer) through a simple application of the single-cone technique. The overall success rate of RCT in maxillary fourth premolars was 90.83%, with 8.33% no evidence of failure (NEF) and 0.83% failure. There were no significant differences between the three different sealers. Furthermore, preexisting periapical lesion (PAL) was reconfirmed as a factor in reducing the success rate of RCT. In addition, the working length and master apical file of each root were analyzed in our study as a novel reference for endodontic veterinarians.

Comparative Evaluation of Solite RS3 and HyFlex Remover Retreatment Files in Conserving Remaining Dentin Thickness During Endodontic Retreatment Using Cone Beam Computed Tomography: An In Vitro Analysis.

Introduction Non-surgical retreatment is seen as a conservative choice for dealing with recurrent infections, instead of opting for periapical surgery. The retreatment processes should be promptly and efficiently carried out, utilizing a suitable armamentarium. The objective of this experiment is to evaluate the quantity of root dentin that remains following the removal of gutta-percha (GP) from the root canal employing two distinct retreatment files. Materials and methods Sixty single-rooted teeth were selected for the examination. The process of shaping and cleaning was performed using the step-back approach, with a master apical file size of 40. The smear layer was effectively eliminated by rinsing with a solution of 3% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Paper points were employed to desiccate the canals. The obturation process involved the utilization of the lateral compaction technique with the AH Plus sealer (Dentsply Sirona, NC, USA). The teeth were classified into two groups: Group I (n=30) underwent retreatment using HyFlex Remover (Coletene India, Pvt., Ltd.), whereas Group II (n=30) received therapy with Solite RS3 retreatment files (Solite Dental in Chennai, India). The remaining dentin thickness (RDT) was assessed by cone beam computed tomography at levels 3, 6, and 9 mm from the cemento enamel junction after the removal of GP. The acquired data underwent examination using an independent t-test to determine statistical significance. Results The findings demonstrate that the utilization of Solite RS3 files led to a higher level of dentin thickness remaining at 3 mm, 6 mm, and 9 mm on the mesial side in comparison to HyFlex Remover retreatment files. The observed difference was found to be statistically significant at a significance level of p<0.05 on the mesial side. Nevertheless, there was no notable disparity seen between the two file types at these three levels on the distal side (p>0.05). Conclusion Based on the obtained results of the study, it can be concluded that Solite RS3 files show promise in preserving the RDT. However, further studies encompassing diverse parameters are needed to establish a conclusive and definitive conclusion.

Effect of Coronal Flaring on Initial Apical File Size Estimation in Curved Canals Using Three Distinct Rotary Instruments: A Comparative In Vitro Study.

The initial size of a root canal is established by progressively introducing K-files according to the increase in the International Organization for Standardization (ISO) size in the apical region. The initial file-fit sensation is caused by coronal interferences rather than always occurring at the apex, as is commonly believed. Flaring the canal at its earliest stages enables the practitioner to accurately assess the size of the canal approaching the apex. This enables more informed judgments on the selection of the master apical file required for shaping and cleaning the apex. The aim of this in vitro study is to examine the impact of cervical flaring on the first estimation of apical file size using three distinct rotary instruments. Sixty-four extracted permanent maxillary first molars with a curvature of between 10⁰ and 20⁰ were chosen. Conventional access openings were made, and the precise length of the canal was determined, leaving it 1 mm short of the apex. The apical fit was deemed to have materialized when the largest file successfully reached the apex, and further progression beyond that depth was unattainable. An initial file that exhibited tactile resistance both before and following expansion at the designated working length (WL) was observed. The initial file that elicited a sensation of being securely attached was affixed using methacrylate into the root canal. A diamond sectioning disc was used to horizontally cut the apical 0.5 mm of the mesiobuccal root. This was done to expose the canal and the instrument at the WL. The uppermost portions were observed using a 3D optical profilometer, and digital photographs were captured for each sample. The occurrence of coronal interferences and the choice of instruments for flaring had a notable impact on the estimation of the initial apical file (IAF) size. The file size frequency was augmented following flaring using various rotary instruments, namely ProTaper, HyFlex CM, and Endoflare. Group 1, which did not undergo preflaring, exhibited the highest disparity of 257.3 ± 54.4. The variation was substantially different (p<0.01) from all the groups that underwent flaring. The use of HyFlex CM (group 3) for preflaring resulted in the smallest average difference (124.4 ± 29.6) between the maximum diameter of the canal at the apex and the diameter of the initial file used. Endoflare (group 4) exhibited the second lowest mean disparity (178.7 ± 46) between the maximum width of the apical root canal and the diameter of the IAF, with the ProTaper group (211 ± 43.5) following closely behind. Nevertheless, there was no statistically significant discrepancy observed in the average differences between groups 2 and 4 (ProTaper and Endoflare groups, respectively). Coronal preflaring significantly contributes to minimizingthe variation between the IAF and the diameter of the apical canal. Prior coronal expansion using rotary files enables a more precise identification of the IAF. The choice of equipment used for flaring affects the estimation of the IAF size.

Comparative evaluation of incidence of dentinal defects after root canal preparation using three different endodontic retreatment systems - An in vitro study.

Safe and efficient removal of all root filling materials from the root canal system without compromising radicular dentin structure is essential for optimal nonsurgical retreatment. The aim of this study was to evaluate and compare the incidence of dentinal defects caused during root canal filling removal using conventional, rotary, and reciprocating retreatment file systems. A detailed protocol explaining purpose and procedures of the study was submitted to the Institutional Ethics Committee and ethical clearance obtained. Sixty human maxillary permanent central incisors were collected and decoronated to 12-mm standardized length. The canals prepared up to a master apical file size F3 with Protaper hand files, obturated using AH plus sealer, examined under the stereomicroscope (×40 magnification): Group I: Control (n = 15), Group II: Conventional (n = 15), Group III: Protaper Universal Retreatment Files (n = 15), and Group IV: Reciproc Blue (n = 15). After instrumentation, teeth were sectioned at 3, 6, and 9 mm from the apex to evaluate the presence of dentinal defects under the stereomicroscope. Statistics were performed using the SPSS, version, 25 (SPSS Inc., Chicago, IL, USA). Initially, normality test was done using the Shapiro-Wilk test and data were not normally distributed followed by Kruskal-Wallis test. P < 0.05 is considered statistically significant. Maximum percentage increase in dentinal defects was observed in Protaper Universal Retreatment Files followed by Conventional method and Reciproc Blue. Significantly Reciproc Blue reduced the incidence of dentinal defects after root canal preparation.

Retrievability of Intracanal Medicament from Root Canals: An In-vitro CBCT Volumetric Analysis

Introduction: The complete removal of Calcium Hydroxide {Ca(OH)2 } using various techniques remains a challenge in root canal therapy. One of the most commonly used methods for removing calcium hydroxide is by using a Master Apical File (MAF) along with sodium hypochlorite and Ethylenediaminetetracetic Acid (EDTA). Various new modalities, like Canal Brush, NaviTip and file systems, have emerged to tackle the residual calcium hydroxide in the canal; but none of these methods have been able to completely remove it from the canal. Aim: To evaluate and compare the efficacy of H-files, NaviTip FX and Canal Brushes in removing calcium hydroxide intracanal medicament from root canals. Materials and Methods: This in-vitro study was carried out in the Department of Conservative Dentistry and Endodontics at KM Shah Dental College and Hospital, Vadodara, Gujarat, India, from December 2023 to March 2024. To standardise the length at 14 mm, 30 mandibular premolar teeth (n=30) with a single root were decoronated at the Cementoenamel Junction (CEJ). The working length was determined, followed by the cleaning and shaping of all specimens using ProTaper Rotary Files. Intracanal medicament (Metapex) was placed and the canals were sealed with Glass Ionomer Cement (GIC). The specimens were then placed at 37±1ºC and 100% relative humidity for 30 days. The medicament was subsequently removed by three different protocols: H-file, NaviTip FX and Canal Brush (n=10 each). The residual volumes in the mesial, distal and apical thirds were assessed, referring to the volume of medicament left in the canal, which was measured using Cone-beam Computed Tomography (CBCT). The recorded variables were analysed using one-way Analysis of Variance (ANOVA) post-hoc tests (p&lt;0.05). Results: The Canal Brush removed the maximum amount of Metapex in the apical third (0.108) of the roots of the premolars, followed by NaviTip FX and then H-file. In the middle third of the root, NaviTip FX removed more Metapex than the Canal Brush, followed by H-files. A comparison of retrieval between and within the groups it showed that none of the techniques were capable of removing all the Metapex from the specimens, with p&gt;0.05. Conclusion: The present study demonstrated that the Canal Brush showed superior results in retrieving Metapex from the apical third of the root and the distal side (middle third), whereas NaviTip FX removed more Metapex from the mesial side (middle third) of the root, but H-file exhibited the least efficacy in the retrieval of Metapex. Total removal of calcium hydroxide from the entire canal is not possible regardless of the technique used.

Analysis of the depth of penetration of an epoxy resin-based sealer following a final rinse of irrigants and use of activation systems: An in vitro study.

The objective of the study was to compare and evaluate the depth of penetration of an epoxy resin-based sealer following a final rinse of 17% ethylenediaminetetraacetic acid (EDTA) and 18% 1-hydroxyethylidene 1, 1-diphosphonate (HEDP), with diode laser and passive ultrasonic activation (PUI): an in vitro confocal laser scanning microscopy study. Fifty-two extracted human mandibular premolar teeth with single root and single canal were selected. They were disinfected in 0.1% thymol solution, cleaned of calculus and soft tissues, and stored in 0.1% thymol solution till use. All teeth were radiographed and selected as per the inclusion and exclusion criteria. The teeth were decoronated using a diamond disk under copious water spray to acquire a standardized root length of 14 mm. Working length was established by inserting a size 10-K file into each root canal until it is visible at the apical foramen and by subtracting 1 mm from the recorded length. Instrumentation of the root canal was done till master apical file size of F3 using ProTaper universal, rotary instruments. The canals were irrigated with 2 mL of 3% sodium hypochlorite between successive files. Teeth were randomly divided into four subgroups n = 12 according to the intervention. Passive ultrasonic irrigation and diode laser were used to activate the irrigants. Final irrigation was performed with distilled water. These specimens were examined using confocal laser scanning microscope (OLYMPUS FLUOVIEW FV 3000) for dentinal tubule penetration of the sealer. Two-way ANOVA test and Tukey's multiple post hoc test were used for statistical analysis. Highly significant difference was seen between the groups with EDTA and HEDP, with HEDP demonstrating the highest penetration. Among the activation techniques used in this study, PUI showed the highest penetration of the sealer. The least penetration was seen with diode laser activation and EDTA. The irrigation activation techniques significantly influence the penetration of sealer into root dentinal tubules. When penetration of sealer with different irrigation techniques and irrigants was evaluated, significant greater level of sealer penetration was attained with PUI activation of HEDP.

Measuring the Amount of Apically Extruded Debris of Endosequence ESR, R-Motion, F6 SkyTaper and Endosequence CM Files in Curved Canals: An in Vitro Study

Aim of the study: Assessing the relationship between Endosequence ESR, R-motion, F6 sky taper and Endosequence CM files use in curved canals and the quantity of apically extruded debris. Materials and methods: 60 curved mesial roots of lower molars with 20-30 degree curvature were selected for this study, The samples were then divided randomly into four groups (n = 15)-Group I: EndoSequence ESR, Group II: R-motion (RM), Group III: F6 SkyTaper and Group IV: EndoSequence CM. This research followed the protocol devised by Myers and Montgomery, wherein debris were collected in vials and weighed before and after instrumentation using a 0.00001-sensitive balance. The instrumentation of all groups was terminated at master apical file #25. Irrigation with 10 ml of deionized water was administered using a needle with a side vent. The collected debris weight was calculated by deducting each vial's pre-instrumentation weight from its post-instrumentation weight. The analysis of variance (ANOVA) and the honestly significant difference (HSD) tests were used to assess the statistical significance of the variation in debris levels across the groups under investigation, using a significance level of 0.05. Results: The results revealed that all tested groups had produced apical debris in different amounts. Conclusions: Under the purview of the present investigation, apical debris was produced in all tested groups. The EndoSequence CM produced less amount of debris than other tested groups. While the RM and F6 SkyTaper produced a comparable amount of apical debris. The EndoSequence ESR produced the most amount of apical debris.

Comparative evaluation of a novel herbal formulation with commercially available synthetic solution in cleaning used endodontic instruments: An in vitro study

The study aimed to compare the cleaning effectiveness of a novel herbal solution with commercially available cleaning solution in eliminating biological debris from the surfaces of used endodontic instruments.Thirty freshly extracted human single rooted premolars were decoronated to the standardized length. The root canals were prepared using rotary files till master apical size 35 (0.04 taper) and distilled water as irrigant. Used master apical files were assessed under scanning electron microscope (SEM) at 40x magnification at apical, middle and coronal third of working end independently for debris accumulation on the cutting surface of file and scored. All the specimens were randomly divided according to the group distribution as follows: Group 1: Synthetic cleaning solution, Group 2: Novel herbal cleaning solution. All files were immersed in the solution for five minutes according to the allocated groups and wiped using sterile gauze piece with one complete rotation covering all the flutes. Each used file was again examined under SEM at 40x at apical, middle and coronal third levels by an independent blinded evaluator and the residual debris were scored. The collected data were subjected to independent sample t test (p&amp;#60;0.05).Statistically significant difference was observed amongst the two groups at middle and apical third of endodontic files (p &amp;#60; 0.05), however, difference at coronal third level was insignificant (p &amp;#62; 0.05).The herbal solution effectively removed the clogged debris from endodontic files as compared to commercial formulation.

Removal of Calcium Hydroxide Medicament from the Apical Root Canal using Different Irrigation Methodologies: A Scanning Electron Microscopy Study

Introduction: To evaluate the efficiency of different irrigants and agitation techniques in the removal of calcium hydroxide Ca(OH)2 medicament from the root canal walls. Material and Methods: N=84 mandibular premolars were selected for this study. The root canal of these 84 premolars was cleaned up using the ProTaper rotary system up to the file size F3 and then filled with Ca(OH)2 medicament. For seven days, the root samples were maintained at 37o C and 100% relative humidity. The sample was divided into four groups (n=20 each) using random allocation employing different agitation methods: Group 1- MAF - Master Apical File, Group 2 - PUI - Passive Ultrasonic Irrigation, Group 3 - CB - Canal Brush, and Group 4 - FF - F File. Each group was further subdivided into two subgroups based on the specific chelating agent employed: (a) 10% Citric Acid and (b) 17% EDTA. Longitudinal bisection was performed in the apical (lower) third of the root structure. Further, an assessment was done using SEM (scanning electron microscopy) to study the elimination of Ca(OH)2. Kruskal- Wallis and Mann-Whitney tests were used for statistical analysis. Results: Groups 1 (MAF) and Group 3 (CB) showed a significant statistical difference (p&lt;0.05) when compared to Group 2 (PUI) and Group 4 (FF). An insignificant difference (p&gt;0.05) was seen between the performance of chelating agents (10% Citric Acid and 17% EDTA). Conclusion: Irrespective of the specific chelating agents employed, both the PUI (Passive Ultrasonic Irrigation) and FF (F File) agitation techniques exhibited superior efficacy in the removal of Ca(OH)2 medicament from the apical (lower) third when compared to the CB (Canal Brush) and MAF (Master Apical File) methods.

Evaluation of Apical Transportation and Curve Straightening of Curved Root Canals after Preparation with Different Nickel - Titanium Rotary Systems (Comparative in Vitro Study)

The goals of endodontic preparation were to shape and clean the space of the root canal and remove microorganisms, affected dentin and pulp, the apical foramen and the canal curve should be protected from being transported during endodontic canal preparation. The aim of this study was to evaluate the curve straightening of curved root canals and apical transportation after preparation with four rotary systems. Forty mesial roots of the lower 1st molars teeth only the mesiobuccal canals were used, these roots were immersed into cold clear acrylic , the teeth roots divided into four groups according to rotary system used for preparation of the canals (ten roots for each group):. group I: ProTaper Next rotary system, group II: IRaCe Plus rotary system, group III: HeroShaper rotary system, group IV: ProTaper rotary system, instrumentation were done to size 30 master apical file and with copious irrigation, total amount of 10 ml of 2.5% of sodium hypochlorite (NaOCl) then rinsed the canals with distilled water 5 ml. radiograph was taken for all roots before and after instrumentation in one direction buccolingual using digital radiograph system. The degree of curve straightening of the root canal and the apical transportation were measured using Image J software and Adobe photoshop CS6 software. Statistical analysis was done and the result showed that group IV had the highest mean values in curve straightening and apical transportation, there were significant difference between group IV and all of the other groups and there were non- significant difference between group I , group II and group . All the four used rotary systems produced adequate geometry during canal preparations. However, some apical transportation in ProTaper group was seen, which might need a caution when used protaper in instrumentation of curved canal.

Scanning Electron Microscopic Analysis of Deformation of TruNatomy File Systems: An Ex-vivo Study.

Aim The aim of the study was to assess the instrument deformation following the usage of the TruNatomy(Dentsply Sirona, USA) file system in extracted premolars using Scanning Electron Microscopy (SEM). Materials and Methods For the present study, 84 extracted mandibular bicuspids were selected. The teeth were divided into two groups: Group 1, TruNatomy(n=42), and Group 2, Hero Shaper(Micro Mega, France) (n=42).The samples were shaped with 0.03 taper to size 36 with TruNatomy instruments and 0.04 taper to size 30 with Hero Shaper instruments. 5 ml of 5.25% Sodium Hypochlorite (NaOCl) and 2 ml of 17% ethylenediaminetetraacetic acid (EDTA) were used for the final irrigation of root canals. The master apical file was used to instrument seven teeth samples for assessing the safety of the instruments after multiple uses and autoclaving. So, a total of six files per group was used for the analysis of any distortions, cracks or micro-fractures after instrumentation of 42 teeth, at the tip (D0) and 5 mm from the tip (D5) of the rotary file under SEM at 500x magnification. Statistical analysis To determine the significance between the groups, the Mann-Whitney U-testwas applied. Results The mean surface wear of the instruments, at the tip (D0) in Group 1 was 1.2857 and in Group 2 was 1.4762. The mean spiral distortion of the instruments, at the tip (D0) in Group 1 was 1.1905 and in Group 2 was 1.4286. A statistically significant difference (P<0.05) was observed between the groups for surface wear and spiral distortion at the tip of the file (D0). There was no significant difference between groups for surface wear and spiral distortion values of the instruments at 5 mm from the tip (D5) (P>0.05). Conclusion The instrument distortion of the rotary file systems analysed was minimal following the biomechanical preparation of seven mandibular bicuspids without root curvature, using a single file. Therefore, both rotary file systems can be considered safe.

A Comparative Evaluation of the Apically Extruded Debris from Root Canals Prepared by R-Motion NiTi File System.

Apically extruded debris (AED) is an inherent concern during root canal treatment for both endodontists and general practitioners. The present study investigates the AED of the novel R-Motion single-file reciprocating system compared to standard single reciprocating and multifile rotary systems. Fifty-six moderately curved palatal roots of upper maxillary first molars were selected for the present study. The samples were then divided randomly into four groups (n = 14)- Group I: R-motion (RM), Group II: WaveOne Gold (WOG), Group III: ProTaper Next (PTN), and Group IV: HyFlex EDM (HFEDM). The researcher has modified Myers and Montgomery's method to simulate human body temperature. Vials were used to collect debris and weighted using a 0.00001 sensitive balance before and after instrumentation. The instrumentation of all experimented groups was done at 37°C, terminated at master apical file #25. An auto syringe with a side vented needle was used to deliver 8 ml of deionized water for irrigation of each sample during preparation. Vials were stored in a dry sealed desiccator which contained CaSO4 crystals, for 24 hr before weighing. The weight of the collected debris was obtained by subtracting the preinstrumentation weight from the postinstrumentation weight for each vial. The Kruskal-Wallis and Mann-Whitney U tests were performed to analyse the statistical difference in the amount of debris between the tested groups at a 0.05 significance level. The RM system produced less debris extrusion than all tested groups, with a significant difference between the former and the WOG and the PTN systems. However, WOG, PTN, and HFEDM showed no statistically significant difference in the amount of AED. All tested groups produced apical debris in different amounts. The RM produced substantially less AED than WOG and PTN. Meanwhile, WOG, PTN, and HFEDM caused a comparable amount of AED.

Effect of nano-silver gel and calcium hydroxide paste on the bond strength of epoxy-resin based sealer to root canal dentin in anterior teeth: An in vitro study

Aim: The objective of this study was to determine and compare the Push-out bond strength of AH Plus sealer of root canal following prior application of calcium hydroxide (Ca[OH]2) paste and Nano-silver gel as intracanal medication in single-rooted human extracted maxillary incisors.Methodology: Using of ProTaper System up till master apical file # F5 have been carried out to prepare root canals of 30 human extracted maxillary incisors. According to the intracanal medication applied, division of teeth were carried out in random manner into three groups. Group I: Control group (No intracanal medication), Group II: Nano-silver gel and Group III: Calcium hydroxide Ca(OH)2. Three weeks later, the elimination process of the intracanal medications were achieved by using passive ultrasonic irrigation of 5 mL 2.5% NaClO, in addition to that, a 17% (Ca[OH EDTA was used in the step of final flush for duration of 60 seconds succeeded by 5 mL of distilled water. Using the master cone #F5 and AH plus sealer, the single cone approach was used to fill the canals. After 1 week, the universal testing machine was implemented to test the push out-bond strength of the samples, which was performed for a 2-mm-thick of coronal, middle and apical thirds of each root.Results: A remarkable difference was evident between the control group and the comparison groups (p < 0.001). Within the control group, the greatest value was evident (4.85±1.65), followed by calcium hydroxide (2.11±1.17), meanwhile the lowest value was discovered in nano-silver (1.41±1.08). Post hoc pairwise comparisons demonstrated a remarkably higher value in the control group than the rest of groups (p < 0.001) with no statistically remarkable difference between calcium hydroxide and Nano-silver group.Conclusion: Prior calcium hydroxide and nano-silver placement seemed to decrease the push-out bond strength of epoxy resin-based Ah plus sealer.

Efficacy of different chelating agents in smear layer removal

Aim The aim of this study was to assess the ability of 17% EDTA, 10% citric acid, 2.25% peracetic acid and 1% phytic acid (IP6) in removing smear layer from root canal system of human teeth using scanning electron microscopic analysis. Materials and methods Forty freshly extracted single canal human mandibular premolars with nearly straight mature fully developed roots were used in this study. Teeth were decoronated perpendicular to their long axises leaving roots ∼ 13 ± 1 mm. Chemomechanical preparation was done using ProTaper instrument in a crown down technique up to F4 master apical file (40/0.06) with irrigation of 2.5% sodium hypochlorite throughout instrumentation. Depending on the used final irrigation solution, the samples were divided randomly into four experimental groups (n = 10). Group I: 17% EDTA. Group II: 10% citric acid. Group III: 2.25% peracetic acid. Group IV: 1% phytic acid. The experimental time periods were 1 min. These samples were prepared and then observed by using scanning electron microscopic analysis for the absence or presence of smear layer, there by analyzing their cleaning effectiveness in the coronal, middle, and apical thirds of the root canal system. Results In intergroup comparison, there was no statistically significant difference among the four groups. In intragroup comparison, there was no statistically significant difference between coronal and middle thirds. However, there were statistically significant differences between apical third versus both coronal and middle thirds in all tested groups. Conclusions The four tested final irrigation solutions can effectively remove the smear layer from the coronal and middle root canal thirds, but they did not completely remove the smear layer at the apical one third.

The Impact of Different Irrigation Regimens on the Chemical Structure and Cleanliness of Root Canal Dentin.

This in vitro study aimed to evaluate the effect of different irrigation regimens on the chemical composition and cleanliness of root canal dentin. Forty-eight extracted single-rooted permanent human teeth were collected. Root canals were instrumented using step-back technique up to master apical file size 60. Samples were divided into 3 groups (n=16) based on the type of the irrigant used. The irrigation solutions were 5.25% sodium hypochlorite, 2% chlorhexidine gluconate, and saline solution as a control. Root canal cleanliness was assessed using stereomicroscope and scanning electron microscope. Scanning electron microscope energy dispersive X-ray was used for the inorganic analysis. Fourier transform infrared spectrometer was used for the organic analysis. One-way analysis of variance (ANOVA) and multiple comparison post hoc test were used for comparison between the three groups. The highest mean percentage of remaining debris was in saline group followed by chlorhexidine gluconate group. Sodium hypochlorite group showed the lowest mean value of remaining debris. Furthermore, our results showed that canal irrigation with sodium hypochlorite affected the chemical structure of root canal dentin more than chlorhexidine gluconate. Based on the results, 5.25% sodium hypochlorite emerges as the preferred irrigant for root canal treatment. This research sheds light on the significance of irrigation regimens in endodontics and emphasizes the need for careful consideration of irrigant selection in clinical practice.

Reinforcement of Endodontically Treated Teeth by Different Intraorifice Barrier Materials

Background: Fracture incidences are more common in teeth with endodontic therapy and hence endodontic therapy should aim toward the reinforcement of such teeth by placing various restorative materials. Aims: Comparative evaluation of different intraorifice barrier material on strengthening the fracture resistance of teeth requiring endodontic therapy. Methods: Sixty extracted human mandibular premolars with one root were divided into four groups (n = 15); Group 1- Light cured Glass ionomer cement, Group 2 - Nanohybrid composite (NHC), Group 3 - High copper amalgam, Group 4-Control. Decoronation of specimens was done to a standardized length of 14 mm and was instrumented up to International Organization for Standardization (ISO) #30 size master apical file. Gutta percha was used to carry out the obturation by the cold lateral compaction technique. With the exception of the control group, elimination of 3 mm obturation from the coronal portion was done and intraorifice barrier materials were placed. Universal Testing Machine was used for testing fracture resistance. Statistical Analysis: Analysis of variance was applied to analyze the data obtained and pairwise comparison was done by post hoc tukey's test (P &lt; 0.05). Results: Better resistance to fracture incidence was seen with NHCs. Control group presented the least values. Conclusion: On placement of intraorifice barrier materials in teeth with endodontic therapy, there was a reduction in fracture incidence.

Comparison of the Time Required by Six Different Retreatment Techniques for Retrieval of Gutta-Percha: An In Vitro Study

Abstract Objective A retreatment is a conservative approach than periapical surgery in case of failed root canal treatment. Retreatment techniques that are efficient and faster should be the main concern to treat endodontic failure. This study aimed to compare the time required by various hand and rotary retreatment systems for the retrieval of gutta-percha (GP) from root canals. Materials and Methods A total of 120 extracted single-rooted premolar teeth with straight canals were chosen. Biomechanical preparation was completed using the Step-Back approach keeping the master apical file size 35. Then, teeth were down-packed and back-filled with System B device, along with AH Plus sealer. The teeth were categorized into six groups (n = 20) at random as per techniques applied for retrieval of GP: group I hand instrumentation (Hedstrom files and Gates-Glidden drills); group II ProTaper Universal Retreatment (PTUR) system; group III Mtwo Retreatment (Mtwo R) system; group IV D-RaCe; group V R-Endo; and group VI Mani Gutta Percha Remover (NRT-GPR). A chronometer was used to measure the time required for retrieval of GP. Data were examined by comparative evaluation of one-way analysis of variance and chi-square test. Results Among all the retreatment techniques used, D-RaCe was faster in GP retrieval than other groups. NRT-GPR system also took less time than other groups except for the D-RaCe system. The Mtwo R system was the slowest among all groups. Conclusion D-RaCe retreatment instruments required extensively less time for retrieval of GP than other groups (p &lt; 0.001).