Demet Altunbaş

Bactericidal effect of KTP laser irradiation against Enterococcus faecalis compared with gaseous ozone: an ex vivo study.

OBJECTIVE The objective of this study was to evaluate the antimicrobial activity of potassium-titanyl-phosphate (KTP) laser and gaseous ozone in experimentally infected root canals. STUDY DESIGN Eighty single-rooted teeth with straight canals were selected. After preparation and sterilization, the specimens were inoculated with 10 microL Enterococcus faecalis for 24 hours at 37 degrees C. The contaminated roots were divided into 2 experimental groups, 1 negative control group, and 1 positive control group of 20 teeth each: Group 1, KTP laser group; Group 2, gaseous ozone group; Group 3, sodium hypochlorite group (NaOCl) (negative control); and Group 4, saline group (positive control). Sterile paper points used to sample bacteria from the root canals were transferred to tubes containing 5 mL of brain heart infusion broth. Then 10-microL suspension was inoculated onto blood agar plates. The colonies of bacteria were counted and data were analyzed statistically using Kruskal-Wallis 1-way analysis of variance and Mann-Whitney U tests. RESULTS There were statistically significant differences between all groups (P < .05). The saline group had the highest number of remaining microorganisms. Complete sterilization was achieved in the 2.5% NaOCl group. The KTP laser and gaseous ozone did not completely sterilize the root canals. CONCLUSION Both KTP laser and gaseous ozone have a significant antibacterial effect on infected root canals, with the gaseous ozone being more effective than the KTP laser. However, 2.5% NaOCl was superior in its antimicrobial abilities compared with KTP laser and gaseous ozone.

The Influence of Various Irrigants on the Accuracy of 2 Electronic Apex Locators in Locating Simulated Root Perforations

Introduction: The aim of this study was to assess the accuracy of the Dentaport ZX (Morita Co, Kyoto, Japan) and the Rootor (Meta Biomed, Cheongwon‐gun, Korea) electronic apex locators (EALs) in detecting root perforations in dry conditions and in the presence of the following irrigation solutions: 2.5% sodium hypochlorite (NaOCl), 0.9% saline solution (NaCl), and 17% EDTA. Methods: Twenty extracted, single‐rooted human teeth were perforated artificially in the middle section. The actual canal lengths (ALs) up to the perforation site were determined, and then the teeth were embedded in an alginate mold. The electronic measurements of the perforations were obtained using a size 20 K‐file by each EAL in various conditions. For each tooth, the AL was subtracted from the electronic length of the perforation. Statistical analyses were performed using the Friedman and Wilcoxon signed rank tests at a significance level of P < .05. Results: The most accurate measurements for both EALs were obtained in dry conditions. Among the irrigation solutions in the Dentaport ZX group, EDTA gave the most accurate results, and NaOCl gave the least accurate ones. However, measurements with NaCl were closer to the AL than those obtained with EDTA for the Rootor group. Significant differences were noted among the EALs when the measurements were taken with NaOCl, NaCl, and EDTA (P < .05). Conclusions: The Dentaport ZX was more accurate compared with the Rootor in the presence of different irrigants. The content of the root canal affected the accuracy of both EALs. The most accurate measurements were obtained in dry canals. HighlightsThe Dentaport ZX and Rootor apex locators (EALs) detected the root canal perforations within a range of clinically acceptable variations in all conditions.The Dentaport ZX was more accurate compared with the Rootor in the presence of NaOCl, NaCl, and EDTA.The content of the root canal affected the accuracy of the measurements obtained by both EALs. The most accurate measurements were obtained in dry canals.

Influence of Different Kinematics on Apical Extrusion of Irrigant and Debris during Canal Preparation Using K3XF Instruments

Introduction This in vitro study was designed to evaluate the amount of apically extruded irrigant and debris during root canal preparation using K3XF instruments (SybronEndo, Orange, CA) with different kinematics and using hand files with a step‐back technique. Methods A total of 80 extracted mandibular premolars were selected and randomly assigned to 4 groups (n = 20). The root canals were instrumented with K‐type stainless steel instruments using a step‐back technique and with the K3XF system using the following kinematics: reciprocating motion, adaptive motion, and continuous rotation. Bidistilled water was used as an irrigant. Preweighed Eppendorf tubes were used to collect apically extruded debris during instrumentation. Extruded irrigant was collected from the drainage cannula using a plastic insulin syringe, and the volumes were recorded. After complete evaporation of the liquid inside the tube, the weight of extruded debris was determined for each specimen. Data were analyzed statistically using the Kruskal‐Wallis and Mann‐Whitney U tests at a significance level of P < .05. Results Hand file instrumentation was associated with a significantly greater extrusion of debris compared with the K3XF groups (P < .05). Among the different kinematics, the highest mean debris extrusion value was obtained with reciprocating motion and the least with continuous rotation, but this difference was not significant (P > .05). No significant differences were observed between groups in terms of irrigant extrusion (P > .05). Conclusions Hand instrumentation extruded more debris than K3XF instruments that were used with different kinematics. All instrumentation kinematics were associated with apical debris and irrigant extrusion. HighlightsThe purpose of this study was to evaluate the amount of apically extruded irrigant and debris using K3XF instruments with reciprocation, adaptive motion, or continuous rotation and hand files with a step‐back technique.Hand file instrumentation was associated with a significantly greater extrusion of debris compared with the K3XF groups.Among the different kinematics, the highest mean debris extrusion value was obtained with reciprocating motion and the least with continuous rotation, but this difference was not significant.No significant differences were observed between groups in terms of irrigant extrusion.

The efficacy of two rotary NiTi instruments and H-files to remove gutta-percha from root canals.

Objective: The aim of this study was to evaluate the efficacy of R-Endo® and K3® rotary nickel-titanium instruments compared with manual instrumentation with H-files, with use of a solvent, for removal of gutta-percha during retreatment. Study design: Forty five freshly extracted human single-rooted teeth, each with one root canal, were instrumented with K-files and filled using cold lateral compaction of gutta-percha and AH 26® sealer. The teeth were randomly divided into three groups of 15 specimens each. Removal of gutta-percha was performed with the following devices and techniques: Group 1 (H-files), Group 2 (R-Endo®), and Group 3 (K3®). The specimens were rendered transparent for the evaluation of the area of remaining gutta-percha/sealer in buccolingual and mesiodistal directions. Statistical analysis as performed by using one-way ANOVA and Kruskal-Wallis tests (p=0.05). Results: All retreatment techniques used in this study left some filling material inside the root canal. Images in buccolingual and mesiodistal directions showed no significant differences between the groups (p>0.05). Conclusions: Under the experimental conditions, the remaining filling material after retreatment was similar for each group. Key words:Gutta-percha removal, K3®, NiTi, R-Endo®.

In vitro comparison of four different electronic apex locators to determine the major foramen using the clearing technique

OBJECTIVES The aim of this study was to evaluate the accuracy of four electronic apex locators (EALs) (DentaPort ZX, Raypex 5, Endo Master and VDW Gold) in detecting the major foramen using the clearing technique. MATERIALS AND METHODS Forty-eight extracted single-rooted extracted teeth with mature apices were used for the study and divided into four groups of 12 teeth each. All teeth were embedded in an alginate model. Electronic measurements were taken using a size 15 K-file attached to the holder. Then, the teeth were cleared and photographed under a stereomicroscope with a digital camera. The distance between the tip of the file and the major foramen was measured by using an image analysis software program. Positive and negative values were recorded when the file tip was beyond or short of the major foramen and zero value when the file tip and the major foramen coincided. Statistical analysis was performed using the Kruskal-Wallis and Chi-square tests at a significance level of 0.05. RESULTS Mean distance from the file tip to the major foramen were 0.302 ± 0.202, 0.065 ± 0.293, 0.117 ± 0.475, and 0.258 ± 0.160 mm in the DentaPort ZX, Raype 5, Endo Master, and VDW Gold groups, respectively. There were no statistically significant differences among the devices (P > 0.05) . CONCLUSION Under the experimental conditions, all EALs showed an acceptable determination of the major foramen.

Effectiveness of Two Apex Locators to Determine Simulated Horizontal Root Fractures

Corresponding author: Assist. Prof. Dilara Arslan İstanbul Aydın Üniversitesi, Diş Hekimliği Fakültesi Endodonti Anabilim Dalı, İnönü caddesi No:38 34295 İstanbul Tel: 0090 212 411 30 00 E-mail: dilaraarslan@aydin.edu.tr. SUMMARY Aim: The aim of this study was to evaluate in vitro the effectiveness of the two different electronic apex locators (Dentaport ZX and Rootor-EALs) in locating simulated horizontal root fractures. Materials and Methods: Forty extracted human single-rooted teeth with mature apices were randomly divided into two groups of 20 teeth each. An incomplete horizontal fracture was simulated by preparing a with a 0.25 mm thick disk in the middle and apical portion of the root and the teeth were mounted in an alginate mold. The electronic measurements (ELs) of the simulated root fractures were established with a size 10 K-file by each EAL in both fracture levels. The actual canal lenghts (ALs) were measured under a stereomicroscope. The ALs were subtracted from the ELs of the fractures. The data were analyzed using the Mann-Whitney U and the Wilcoxon signed-rank tests at a significance level of P < .05. Results: The mean differences between the ELs and ALs were -0.12 ± 0.27; 0.09 ± 0.38; -0.10 ± 0.25; 0.18 ± 0.53 mm in the Dentaport ZX and Rootor groups and middle and apical horizontal fracture levels, respectively. The Dentaport ZX performed measurements within ±0.5 mm in 18 and in 19 samples while the Rootor performed in 12 and in 11 samples, middle and apical horizontal fracture levels respectively. Statistically, significant differences were found among the EALs at both horizontal fracture levels (P < .05). However; no statistically significant differences were found between the fracture levels in each of the EALs (P > .05). Conclusions: The Dentaport ZX measurements were shorter than ALs whereas the Rootor measurements were longer than Als. Furthermore, the number of measurements obtained within ± 0.5 mm in Dentaport ZX is more than that of Rootor. Under the conditions of this study, the Dentaport ZX group showed an acceptable determination of the horizontal root fracture.

MAXILLARY FIRST PREMOLARS WITH THREE ROOT CANALS: TWO CASE REPORTS

It is very important that the dentists have sufficient information about possible variations in the expected root canal configurations in order to achieve success in endodontic treatment. In addition to having adequate knowledge on the variations of the root canal anatomy, periapical radiographs from different angles, careful examination of the pulp chamber floor, and use of dental operation microscope during the procedure are also important factors that contribute to the diagnosis of the additional roots and canals. The aims of this article are to present the diagnostic approach and root canal treatments of two maxillary first premolar teeth with three canals in two patients.

RECIPROC VERSUS TWISTED FILE FOR ROOT CANAL FILLING REMOVAL: ASSESSMENT OF APICALLY EXTRUDED DEBRIS

Purpose: The aim of this study was to evaluate the amount of apically extruded debris during endodontic retreatment with different file systems. Materials and Methods: Sixty extracted human mandibular premolar teeth were used in this study. Root canals of the teeth were instrumented and filled before being randomly assigned to three groups. Guttapercha was removed using the Reciproc system, the Twisted File system (TF), and Hedström-files (H-file). Apically extruded debris was collected and dried in pre-weighed Eppendorf tubes. The amount of extruded debris was assessed with an electronic balance. Data were statistically analyzed using one-way ANOVA, Kruskal-Wallis, and Mann-Whitney U tests. Results: The Reciproc and TF systems extruded significantly less debris than the H-file (p<0.05). However, no significant difference was found between the Reciproc and TF systems. Conclusion: All tested file systems caused apical extrusion of debris. Both the rotary file (TF) and the reciprocating single-file (Reciproc) systems were associated with less apical extrusion compared with the H-file.

Mtwo ve S5 NiTi döner kanal eğelerinin yapay kök kanalını şekillendirme etkinliklerinin karşılaştırılması

AMAC: Bu calismanin amaci, Mtwo ve S5 nikel-titanyum doner kanal egelerinin yapay egri kanallari sekillendirme etkinliklerinin karsilastirilmasidir. GEREC ve YONTEM: Kirk adet yapay kanal rastgele iki gruba ayrildi (n=20). Kanallar Mtwo ve S5 egelerle apikal cap 30’a kadar sekillendirildi. Dijital kamera kullanilarak elde edilen preoperatif ve postoperatif kanal goruntuleri birlestirildi ve normalden sapmalar kaydedildi. Madde kaldirma 5 farkli noktada olculdu. Istatistiksel degerlendirme 0.05 anlamlilik duzeyinde Kolmogorov-Smirnov testi, independent t-testi ve ki-kare testi kullanilarak yapildi. BULGULAR: Kanallarin ortalama toplam genislikleri, sekillendirmenin apikal son noktasi haric Mtwo grubunda S5 grubundan anlamli olarak daha fazlaydi (p 0.05). SONUC: Mtwo daha genis kanal sekli ortaya koydu. S5 daha merkezi bir apikal sekillendirme sagladi ve orijinal kanal seklini daha iyi korudu.

Shaping ability of reciprocating single-file and full-sequence rotary instrumentation systems in simulated curved canals.

Objective: The purpose of this study was to evaluate the shaping ability of three nickel-titanium systems in simulated curved canals. Materials and Methods: Sixty simulated canals were prepared to apical size 25 with Reciproc, S5, and twisted file (TF) instruments. Standardized pre and postoperative images were taken using a digital camera, were superimposed and aberrations were recorded. Material removal was measured at five points: The canal orifice, halfway to the orifice, beginning of the curve, the apex of the curve, and end-point. The data were analyzed using Kolmogorov–Smirnov, analysis of variance, and Tukey tests. Results: The mean total width of the prepared canals in the Reciproc group was greater than the TF and S5 groups at halfway to the orifice, the beginning of the curve, the apex of the curve, and the end-point (P < 0.05). Mean absolute transportation was always <0.16 mm; however, significant differences occurred between the three systems at the orifice, halfway to the orifice, and the beginning of the curve (P < 0.05). TF created minimal absolute transportation at halfway to the orifice and the beginning of the curve, and greater absolute transportation at the orifice compared with the Reciproc and S5 instruments. However, the difference between the S5 and TF groups was not statistically significant at halfway to the orifice (P > 0.05). Conclusions: Under the conditions of the study, Reciproc produced widest canal shapes. TF provided more centered apical preparation and maintained the original canal shape well.