UNASSIGNED: The aim of this in vitro study was to compare the cyclic fatigue resistance of three different endodontic nickel-titanium rotary instruments using a dynamic testing device.
UNASSIGNED: Ten files each of ProTaper Gold (PG), Hyflex Electro-discharge Machining (HEDM), and TruNatomy (TN) were tested in a custom-fabricated dynamic cyclic fatigue testing device at 60° curvature having a radius of curvature of 5 mm. The number of cycles to the fracture (NCF) of each instrument was calculated and three continuous groups were compared by the Kruskal-Wallis test and Dunn post hoc test was used for pairwise comparison.
UNASSIGNED: Cyclic fatigue resistance of HEDM was the highest, followed by TN. PG had the lowest among the three.
UNASSIGNED: Within the limitations of the present in vitro results, it can be concluded that HEDM files appeared to be suitable for shaping complex canals with the greater number of cycles before it fractures.

UNASSIGNED: Recent innovations in the physical and mechanical features of endodontic file systems have diminished the prospect of stress generation and fracture risk in novel endodontic files.
UNASSIGNED: The purpose of this research was to comparatively evaluate the stress distribution of recently introduced endodontic rotary files with distinct features and metallurgy at three different levels of the root canal wall by finite element analysis.
UNASSIGNED: Forty endodontic files were used in this experiment after being inspected through a scanning electron microscope for any surface deformities. Based on their metallurgy and design, the scanned files were divided into four groups, each with 10 samples: Group A-2Shape files, Group B-F360, Group C-One Curve, and Group D-TruNatomy. To assess the mechanical behavior of these files, the stress produced by computer-aided models of these instruments on the dentinal wall of a simulated root canal was numerically analyzed using ANSYS® 15 Workbench finite element software.
UNASSIGNED: A one-way ANOVA was used to assess all the raw data with post hoc Tukey analysis, the Shapiro-Wilk test, and Levene\'s test. F360 files exerted the maximum stress on the dentinal wall, while TruNatomy files exerted the least stress at all the distinct levels of dentinal walls.
UNASSIGNED: There was no statistically significant variation in the stress generated between the four groups. Therefore, it can be concluded that improvements in rotary file design and metallurgy have the potential to reduce the stress during canal shaping and the risk of instrument breakage during clinical use.

Dental caries is indeed the biggest cause of tooth loss, particularly in the primary dentition. In primary teeth with carious pulp involvements, endodontic intervention in the form of pulpotomy (removal of only the coronal pulp) or pulpectomy (removal of coronal and radicular pulp) is advocated. Pulpectomy can be laborious and time-consuming, especially when using traditional hand endodontic files to shape root canals. In paediatric dentistry, motorised nickel-titanium (Ni-Ti) rotary instrumentation has proved significant in enhancing the quality of pulpectomy. In primary dentition, however, these files may leave more than half of the root canals unaltered by instrumentation, just as they do in permanent dentition. The XP-endo® Shaper is a revolutionary heat-dependent endodontic file that uses an asymmetrical rotating motion to address the maximum area of the root canal space, resulting in anatomic root canal instrumentation. The case series describes the use of this novel XP-endo® Shaper file for anatomic root canal instrumentation in primary molars with irreversible pulpitis. The purpose is to demonstrate the efficacy and advantages of this cutting-edge endodontic treatment method. This case series can be an informative resource for other endodontic specialists by providing a practical illustration of how adaptable instrumentation can be utilised to successfully treat a patient. In conclusion, The use of the XP-endo Shaper® for pulpectomy demonstrated faster and instrumentation that was confined with the original shape of the canals, although further research is required to fully utilise these findings.

UNASSIGNED: To assess the canal transportation and centering ability in the mandibular first molars\' curved mesiobuccal canals after instrumentation with file systems XP endo Shaper, self-adjusting File (SAF), Hyflex EDM, Pro Taper NEXT, WaveOne Gold, and K files with the help of Cone-Beam Computed Tomography (CBCT).
UNASSIGNED: Ninety recently extracted mandibular first molars with mesiobuccal roots that had a 25-30 degree canal curvature were assessed. Following preoperative CBCT scans, teeth were allocated randomly to six experimental groups of fifteen. After preparation with XP endo Shaper, SAF, Hyflex EDM, Pro Taper Next, WaveOne Gold, and K files, post-instrumentation scans were taken using same parameters as pre operative scans. At 3 mm, 6 mm, and 9 mm from the apex, samples were assessed for canal transportation and centering ratio.
UNASSIGNED: Apical transportation was least for XP endo Shaper as compared to other groups except SAF and the results were statistically significant. K file showed the highest apical transportation toward the lateral wall of the root canal. XP endo Shaper was better in maintaining centering ability of middle and apical third of canal and SAF was better in maintaining centering ability of coronal third.
UNASSIGNED: In root canal preparation, least apical transportation and better centering ability with XP endo Shaper than other file systems compared. K file showed the highest transportation.

UNASSIGNED: The endodontic preparation depends largely on the file systems that are used in the canal preparations. The amount of the intracanal debris that is extruded from the apex may be influenced by the file systems. Hence, the present in vitro study evaluated the amount the debris that is extruded for the two file systems at different working lengths.
UNASSIGNED: Forty human mesiobuccal canals of the first molars were collected that were extracted for various causes. They were equally divided to four groups of Reciproc (full length), Reciproc (short by 1 mm), WaveOne Gold (full length), and WaveOne Gold (short by 1 mm). Routine crown-down technique was followed for the canal preparation with the intermittent irrigation. The extruded debris was weighed and compared for the significance.
UNASSIGNED: The amount of the debris that was extruded weighed similarly in all the four groups with no significant variations. The Reciproc extruded lesser material than the WaveOne Gold.
UNASSIGNED: The file systems seem not to affect the debris extrusion irrespective of the files\' physical properties. Further studies in a clinical setup are warranted.

BACKGROUND: The use of file systems that work with different principles in root canal treatment is becoming widespread. The aim of this study was to evaluate the remaining dentine volume in the coronal region of the root and preparation efficiency after the use of conventional hand files, WaveOne Gold; which works with reciprocating motion, and TruNatomy; which works with rotational motion in the root canal treatment of mandibular molar teeth.
METHODS: All canals of permanent mandibular molars (n = 36) were used. Root canals in each group (n = 12) were prepared with conventional hand files, WaveOne Gold, and TruNatomy. The three-dimensional images were evaluated for remaining dentine volume in the coronal two-millimeter region of the root and change in volume of the entire root canal space.
RESULTS: There was no statistically significant difference between the groups in terms of mean differences pre and postpreparation (P > .05). The mean differences after preparation were observed the most in the WaveOne Gold group and the least in the TruNatomy group in the coronal two-millimeter region of the root and entire canal volume, but the differences were not significant (P > .05, P > .05, respectively).
CONCLUSIONS: Conventional hand files, WaveOne Gold working with reciprocating motion, and TruNatomy working with rotational motion, which are the file systems used in the study, are not superior to each other in terms of remaining dentin volume in the coronal two-millimeter region of the root and preparation efficiency in the entire root canal space in mandibular molars.

This study aimed to evaluate the efficacy of intracanal Enterococcus faecalis reduction using pediatric rotary (EndoArt Pedo Kit Blue, EasyInSmile X-Baby and Denco Kids), rotary (ProTaper Next) and reciprocating (WaveOne Gold) file systems through microbiological analyses in primary molars. Seventy-five mandibular primary second molars were selected and divided into five instrumentation groups and a negative control group. After incubation, five roots were used to confirm biofilm formation on the root canals. Before and after instrumentation, bacterial samples were collected. The bacterial load reduction was statistically analyzed by using Kruskall-Wallis and Dunn post hoc tests at a significance level of 0.05. Denco Kids and EndoArt Pedo Kit Blue promoted higher bacterial reduction than EasyInSmile X-Baby systems. There was no difference in bacterial reduction between ProTaper Next rotary file systems and other groups. Among the single-file techniques, instrumentation with the Denco Kids rotary system showed a more significant bacterial load reduction than WaveOne Gold (p < 0.05). All systems used in the study reduced bacterial counts from root canals in primary teeth. Further studies are required to generate more information about the use of pediatric rotary file systems in clinics.

UNASSIGNED: The purpose of the present study was to comparatively evaluate the efficacy of Kedo-SG blue rotary files, manual K-files, and manual H-files in eliminating the root canal microflora of primary molars.
UNASSIGNED: Forty-five primary molars requiring pulpectomy were included in the study. Based on type of instrumentation, the teeth were randomly assigned to one of the three groups: group A: Kedo-SG blue rotary files, group B: manual H-files, and group C: manual K-files. Sterile absorbent paper points were used for sample collection and stored in sterile Eppendorf tubes containing saline as transport medium. Culturing was done on thioglycolate agar and blood agar media for the cultivation of anaerobic and aerobic microbes, respectively, and recorded as colony-forming units (CFU) using digital colony counter. Wilcoxon signed-rank test and one-way analysis of variance (ANOVA) test were performed for statistical analysis.
UNASSIGNED: Postinstrumentation, 93-96% reduction of aerobic and anaerobic microbial count was recorded in group A. Whereas, it was 87-91% reduction in group B and 90-91% reduction in group C. No statistically significant difference was noted between the three groups.
UNASSIGNED: Kedo-SG blue rotary files showed a better reduction of microbes in root canals when compared to manual instrumentation. However, there was no significant difference between manual and rotary instrumentation in microbial reduction of primary root canals.
UNASSIGNED: Lakshmanan L, Jeevanandan G. Microbial Evaluation of Root Canals after Biomechanical Preparation with Manual K-files, Manual H-files, and Kedo-SG Blue Rotary Files: An In Vivo Study. Int J Clin Pediatr Dent 2022;15(6):687-690.

It is very important for clinicians to provide restorative treatments that provide durability for endodontically treated teeth. Trauma, occlusal premature contact, and features of teeth are some of the issues that can cause vertical root fractures (VRFs) in root canal-treated teeth. The aim of this 3-D study was to compare stress distribution on mandibular premolar teeth when using a variety of post designs instrumented with different rotary systems. Six mandibular premolar teeth were instrumented with the following tools: ProTaper Next, WaveOne (WO), Reciproc (R), ReciprocBlue (RB), F6-Skytaper, and TF-Adaptive. Teeth were scanned using cone beam computed tomography (CBCT) and the images were transferred to the Catia V5R25 software. Data were recorded in a stereolithography (STL) format. Four different post systems were used, fabricated from metal, fiber, zirconia, and titanium, respectively. Dentin, gutta, post, core, and crown models were added to the solid model. ANSYS V17.2 finite element analysis (FEA) software was used to determine stress distribution on each assembly. Finite analysis models were created that allowed for the calculation of stress distribution of 250-N loading at a 45° angle and vertical in relation to the roots. The maximum principal stress and von Mises values were higher under oblique loading on the roots. The F6-Skytaper and WO systems showed lower stress than other systems. The TF-Adaptive instrument showed higher stress distribution than the other models. Fiber and titanium posts showed lower stress than others. The F6-Skytaper, R, and RB instruments were found to be most effective in terms of displacement of the crown, resulting in the lowest stress values. Fiber and titanium posts showed better results than other post systems, while root canals instrumented with the F6-Skytaper and WO instruments were less likely to result in root fractures.

UNASSIGNED: The objective of this study was to compare the mechanical and structural properties of the nickel-titanium (Ni-Ti) alloy already used in endodontics with titanium-molybdenum (Ti-Mo) and titanium-niobium (Ti-Nb) alloys to determine if these can be suggested in the manufacture of endodontic files.
UNASSIGNED: Orthodontic wires made of the different alloys were used. The previously mentioned alloys were characterized by energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and torsion tests. Cyclic fatigue tests were performed on a simulated canal with a curvature of 86° to 375 rpm. The fractured surfaces of the wires were observed by means of scanning electron microscopy (SEM). A Kruskal-Wallis test and U Mann Whitney test were used to determine significant differences in cyclic fatigue between groups.
UNASSIGNED: In the mechanical tests, similar values of torsion were found for the three alloys. In XRD, the Ti-Nb showed less structural changes. In the cyclic fatigue test, Ti-Nb was found to be significantly more resistant with respect to Ni-Ti and Ti-Mo.
UNASSIGNED: Based on our in vitro study, Ti-Nb is suggested as a possible alloy for the manufacture of rotary files due to its impressive properties.