Ersan Çiçek

Evaluation of Microcrack Formation in Root Canals After Instrumentation With different NiTi Rotary File Systems: A Scanning Electron Microscopy Study

The aim of this study was to evaluate the dentinal microcrack formation of ProTaper Universal, ProTaper Next, and WaveOne. Sixty extracted mandibular molars were selected. The mesial roots were resected and randomly divided into four groups (n = 15). The canals were prepared with hand files (group 1), ProTaper Universal (group 2), ProTaper Next (group 3), and WaveOne (group 4) instrument systems. The roots were separated horizontally at 3, 6, and 9 mm from the apex. Digital images were captured at ×40 magnification using scanning electron microscopy to detect microcrack formation. Statistical analysis was performed by Pearson Chi-square test. The prevalence of microcracks in group 2, group 3, and group 4 were significantly higher when compared to group 1 (p < 0.001). Group 2, group 3, and group 4 demonstrated similar prevalence of microcracks without significant difference (p > 0.05) in all sections. All instruments caused microcracks except for hand file. The highest percentage of microcrack was recorded in 3 mm section for all groups.

Influence of Diode Laser Application on the Efficiency of QMiX and EDTA Solutions in Removing Smear Layer

OBJECTIVE The aim of this study was to compare the efficacy of QMiX and ethylenediaminetetraacetic acid (EDTA) solutions with diode laser treatment in smear layer removal. BACKGROUND DATA Removing the smear layer from the apical thirds of root canals is difficult, regardless of the solution used. Researchers have been improved some irrigation agitation methods to overcome this challenge, and agitation of irrigants with laser devices has become popular. METHODS Seventy-five extracted mandibular premolars were used. After root canals were, prepared the specimens were divided into five groups (n = 15): Group 1, no irrigation; Group 2, 17% EDTA; Group 3, QMiX solution; Group 4, 17% EDTA with diode laser; and Group 5, QMiX with diode laser. The roots were split longitudinally and prepared for scanning electron microscopic (SEM) investigation. The smear layer was evaluated under × 500, × 1000, and × 2000 magnifications. RESULTS The amount of smear layer was found significantly high in the control group (p < 0.001). In the EDTA group, the amount of smear layer was significantly high at the apical thirds, and the differences among the three regions were statistically significant (p < 0.001). In the QMiX group, no difference was found between the coronal and middle thirds; however, the amount of smear layer was significantly high at the apical thirds (p < 0.001). In the EDTA plus laser and the QMiX plus laser groups, the smear layer was found significantly high at the apical thirds (p < 0.001). However, no differences were found between the coronal and middle thirds in either group. CONCLUSIONS None of the solutions completely removed the smear layer, especially at the apical thirds. Diode laser treatment with solutions decreased the amount of smear layer, without significance.

Influence of passive ultrasonic irrigation on the efficiency of various irrigation solutions in removing smear layer: A scanning electron microscope study

To evaluate the influence of passive ultrasonic irrigation (PUI) to remove the smear layer with different irrigation solutions. Seventy‐eight single rooted mandibular premolars were used. The working lengths were measured and the root canals were prepared by using nickel titanium rotary files. The specimens were subjected to six different irrigation regimens: sodium hypochloride (NaOCl) with classic irrigation (CI); NaOCl with PUI; EDTA with CI; EDTA with PUI; QMix with CI; and QMix with PUI. The specimens were split longitudinally. Scanning electron microscopy images were taken to evaluate the amount of residual smear layer and scored. Statistical analysis was performed with the Kruskal–Wallis test. The Dunns test was used for post hoc testing after the Kruskal–Wallis test. The smear layer scores of apical thirds were significantly higher than coronal and middle thirds except for NaOCl + CI group (p < 0.001). The irrigation with PUI improved the efficacy of all irrigation solutions on removal of smear layer in both coronal and middle thirds (p < 0.001). The PUI activation increased the activity of NaOCl, EDTA, and QMix, respectively without any significance. All irrigation regimens were significantly more effective in coronal and middle thirds compared to apical third. PUI significantly increased the efficacy of smear layer removal regardless of irrigation solution.

Postoperative pain intensity after using different instrumentation techniques: a randomized clinical study

Abstract Postoperative pain is a frequent complication associated with root canal treatment, especially during apical instrumentation of tooth with preexisting periradicular inflammation Objectives The aim of this clinical study was to evaluate the influence of the instrumentation techniques on the incidence and intensity of postoperative pain in single-visit root canal treatment. Material and Methods Ninety patients with single root/canal and non-vital pulps were included. The patients were assigned into 3 groups according to root canal instrumentation technique used; modified step-back, reciprocal, and rotational techniques. Root canal treatment was carried out in a single visit and the severity of postoperative pain was assessed via 4-point pain intensity scale. All the participants were called through the phone at 12, 24 and 48 h to obtain the pain scores. Data were analyzed through the Kruskal–Wallis test. Results There was significant difference between all groups (p<0.05). The modified step-back technique produced postoperative pain significantly lower than the rotational (p=0.018) and reciprocal (p=0.020) techniques. No difference was found between the reciprocal and rotational techniques (p=0.868). Postoperative pain in the first 12 h period (p=0.763) and in the 24 h period (p=0.147) was not significantly different between the groups. However, the difference in the 48 h period was statistically different between the groups (p=0.040). Conclusion All instrumentation techniques caused postoperative pain. The modified step-back technique produced less pain compared to the rotational and reciprocal techniques.

Comparison of apically extruded debris associated with several nickel-titanium systems after determining working length by apex locator.

Background/Aim: To compare apically extruded debris using ProTaper Universal (PTU), ProTaper Next (PTN), WaveOne (WO), Twisted File (TF), M-Two (MT), and Revo-S (RS) after determining the working length (WL) with root ZX. Materials and Methods: Seventy-two teeth were selected. The WL determination was performed with root ZX. The teeth were divided into six experimental groups, randomly. In groups, root canals were prepared with PTU to size F4/0.06, with PTN to size X4/0.06, with WO to size 40/0.08, with TF to size 40/0.04, with MT to size 40/0.06, and with RS to size AS40/0.06. After preparations were completed, final irrigation was performed with 2 mL distilled water, and a total of 10 mL of distilled water was used in each tooth. Tubes were stored in an incubator at 68°C for 5 days to evaporate the distilled water before weighing the dry debris. Data were analyzed by the Mann-Whitney U-test. Results: The RS group led to the highest amount of extruded debris, however, WO led to the least amount of extruded debris. There was no statistically difference among the groups (P > 0.05). Conclusions: The authors conclude that the results obtained might depend on the apex locator used to determine the WL.

Apical transportation during removal of root canal filling with different retreatment systems

Introduction This study aimed to compare apical transportation during retreatment using ProTaper Universal retreatment (PTUR), Mtwo R and D-RaCe instruments in curved root canals. Methods 36 extracted mandibular molar teeth with curved mesiobuccal roots were selected. The teeth were embedded into acrylic blocks. The blocks were fixed on the experimental setup. After determining the working length (WL), mesiobuccal canals were prepared with ProTaper Universal rotary instruments to size F1 (20/0.06). After the obturation, the teeth were randomly divided into groups; the PTUR files were used as D1 (30/0.09) for coronal third and D2 (25/0.08) at WL Mtwo R files, R1 (15/0.05) and R2 (25/0.05) were used at WL D-RaCe files were used as DR1 (30/.10) in cervical third and DR2 (25/0.04) at WL Image J analysis software was used to measure the apical transportation. Differences between the 3 groups were analyzed with a 1-way ANOVA or Kruskal-Wallis tests. Results There was no significant difference between groups in the apical transportation in either the mesiodistal (p = 0.166) or buccolingual (p = 0.518) direction. Among the 3 groups, the apical transportation was the greatest in the D-RaCe group. Conclusions It can be concluded that all retreatment systems caused a similar level of apical transportation.

Effect of retreatment instruments on microcrack formation: a microcomputed tomography study

Introduction The purpose of this study was to compare the occurrence of microcracks in teeth prepared with different retreatment systems using microcomputed tomography (micro-CT). Methods Forty-two freshly extracted mandibular premolar teeth were used. The root canals were instrumented with stainless steel K-files to an apical size of 35/.02 using the balanced-force technique and were obturated using the passive compaction technique. The specimens were divided into 3 experimental groups according to retreatment system used (n = 14): ProTaper Universal retreatment (PTUR), Mtwo retreatment (MTR), or D-RaCe retreatment (D-RC) systems. Each specimen was scanned using a high-resolution micro-CT system before instrumentation, after obturation, and after the removal of the filling material. The images were evaluated, and the presence of microcracks was recorded. Results The PTUR system demonstrated the highest percentage, while MTR and D-RC retreatment systems resulted in similar numbers of microcracks. Conclusions Clinicians should be aware that all retreatment systems may cause microcracks.

Root canal treatment of permanent mandibular first molar with six root canals: a rare case

The awareness of internal dental morphology is an excessively critical step in management of endodontic therapy. [1] The mandibular first molar, the earliest permanent tooth to erupt is assumed to be the tooth that mostly creates need for root canal treatment. The most common root canal morphology of the mandibular first molar is the presence of two canals in the mesial root and one or two canals in the distal root.[2] However, the literature indicates a number of case reports on the anatomic alterations and the variations related to the mandibular first molars. Amazingly, Reeh[3] reported a case with seven canals, involving four canals in the mesial root and three canals in the distal root. The knowledge of such anatomic variations of root and root canals is an essential aspect in managing the degree of success of root canal treatment. Without an efficient exploration, a canal could be left unprepared and inaccurate disinfection of root canal system is inevitable, so the endodontic therapy may result in failure.[4]

The influence of determining the working length with an apex locator on the amount of apically extruded debris following instrumentation with ProTaper Next and HyFlex CM

Aim: The amount of apically extruded debris caused by new nickel-titanium rotary systems after determination of the working length (WL) with an apex locator has not been investigated. To compare the amount of apically extruded debris with ProTaper Next (PTN) and HyFlex CM systems after determination of WL with/without an apex locator. Materials and Methods: Forty-eight extracted mandibular incisor teeth divided into four groups were used in this study. In Groups 1 and 2, a 10 K-file was progressed until it was just visible at the major apical foramen and WL was recorded as 1 mm short. In Groups 3 and 4, the WL was determined with the Root ZX (sensitivity of 0.1) using a 10 K-file. During the instrumentation, the PTN was used to X2 in groups 1 and 3, and the HyFlex CM was used to 25/.06 in groups 2 and 4. Distilled water was used as an irrigant. Debris was collected in tubes then stored in an incubator at 68°C for 5 days to evaporate the distilled water. The Eppendorf tubes, including the extruded debris, were weighed to obtain final weights. The amount of extruded debris was calculated by subtracting the weight of the empty tube from the weight of the dry tube. Data were analyzed by Kruskal–Wallis and Mann–Whitney U-test. Results: Less apically extruded debris was obtained in Group 3, with a significant difference compared to Group 1 and Group 2 (P < 0.05). Conclusions: The usage of apex locator to determine the WL decreased the amount of apically extruded debris. In addition, PTN caused less apical debris extrusion after determination WL with/without apex locator.

Retrieval of the Separated Canal Instruments Within the Root Canal During Root Canal Treatment Procedures: Case Series

Separation of endodontic instrument within the root canal is an unwanted complication during root canal preparation that could effect treatment outcome negatively. Main reasons of instrument separations are using extensive force and repeated use of file. When an instrument separation occurs clinician should inform the patients about the treatment options which are removing the fragment, bypassing the fragment or cleaning/shaping and fiiling of the root canal to the level of the fragment. This article reports series of separeted instrument cases that occurs in clinics and its managment. In these cases Masserann kit and ultrasonics were used. While removing a broken instrument, using the combination of improved armamentarium and treatment by an experienced specialist might increase the success rate..