Alper Kuştarcı

Apical extrusion of intracanal debris and irrigant following use of various instrumentation techniques

OBJECTIVE The purpose of this study was to compare in vitro the amount of debris and irrigant extruded apically from extracted teeth, using manual technique and crowndown pressureless technique by K3, RaCe, and FlexMaster instruments. STUDY DESIGN Sixty human single-rooted mandibular premolar teeth were randomly assigned to 4 groups, 15 teeth each. The teeth in 4 groups were instrumented until the working length with RaCe, K3, FlexMaster, and K-type stainless steel instruments respectively. Debris and irrigant extruded from the apical foramen were collected into vials and the amounts were determined. The data obtained were analyzed using Kruskal-Wallis 1-way analysis of variance and Mann-Whitney U tests, with alpha = 0.05 as the level for statistical significance. RESULTS No statistically significant difference was observed among the groups in terms of debris extrusion (P > .05). On the other hand, a statistically significant difference was observed between K3 and manual technique groups in terms of irrigant extrusion (P < .05). The difference between other groups was not statistically significant (P > .05). CONCLUSION Based on the results, all instrumentation techniques produced extruded debris and irrigant; however, the engine-driven nickel-titanium systems were associated with less apical extrusion and irrigant.

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.

Apical extrusion of intracanal bacteria following use of various instrumentation techniques

AIM To evaluate the number of bacteria extruded apically from extracted teeth ex vivo after canal instrumentation using a manual technique and three engine-driven techniques utilizing nickel-titanium instruments (K3, RaCe, and FlexMaster). METHODOLOGY Seventy extracted human mandibular premolar teeth with similar dimensions were used. Access cavities were prepared and root canals were then contaminated with a suspension of Enterococcus faecalis and then dried. The contaminated roots were divided into four experimental groups of 15 teeth each and one control group of 10 teeth. G1. RaCe group: the root canals were instrumented using RaCe instruments. G2. K3 group: the root canals were instrumented using K3 instruments. G3. FlexMaster group: the root canals were instrumented using FlexMaster instruments. G4. Manual technique group: the root canals were instrumented using K-type stainless steel instruments. G5. CONTROL GROUP no instrumentation was attempted. Bacteria extruded from the apical foramen during instrumentation were collected into vials. The resultant microbiological samples were removed from the vials and then incubated in culture media for 24 h. The number of colony-forming units (CFU) was determined for each sample. The data obtained were analysed using the Kruskal-Wallis one-way analysis of variance and Mann-Whitney U-tests, with alpha = 0.05 as the level for statistical significance. RESULTS There was a significant difference between experimental-control and engine-driven-manual technique groups (P < 0.05). The manual technique was associated with the greatest extrusion of microorganism. CONCLUSIONS All instrumentation techniques extruded intracanal bacteria apically. No significant difference was found in the number of CFU among the engine-driven techniques; manual techniques extruded significantly more microorganisms.

Efficacy of Surface Roughness and Bond Strength of Y-TZP Zirconia After Various Pre-Treatments

OBJECTIVE The aim of this study was to evaluate surface roughness (SR) and the influence of various surface treatments (STs) on the veneer ceramic shear bond strength (SBS) to Y-TZP zirconia. BACKGROUND DATA STs can improve the bonding properties of zirconia ceramics. However, little is known about the effect of Er,Cr:YSGG laser irradiation on SBS between zirconia and veneer ceramic/resin cement. METHODS Eighty ceramic discs of yttria-tetragonal zirconia polycrystals (Y-TZP) were prepared, and specimens were divided into eight groups (n=10): untreated (control), air abrasion, and Er,Cr:YSGG laser irradiation with different energy intensities (1-6 W). Average SR of each specimen was determined with a profilometer, and a veneering ceramic recommended for zirconia was fired into cylinder-shaped Y-TZP specimens. SBS test was performed for each specimen at a crosshead speed of 1 mm/min, and the average means of SBS and SR were calculated. Fracture modes and the surface topography were evaluated with various microscopes after STs. Data were analyzed by using one way analysis of variance (ANOVA) and Tukey honest significant difference (HSD) tests. RESULTS The highest mean force value was observed in the air abrasion group, and followed by 6 and 5 W laser irradiations, respectively. The difference between control and air abrasion groups was found to be statistically significant (p<0.05). All laser irradiations increased the SBS value, but 1 and 2 W laser irradiations showed no statistically significant differences compared with the control group. However, the SR value for air abrasion group was significantly higher than that of the control group and 1 W (p<0.05), and there were no significant differences between the SR of all the laser groups and the control group. CONCLUSIONS The result of this study showed that STs with air abrasion and high laser energy intensities (3-6W), can improve the bonding properties of Y-TZP zirconia.

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®.

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.

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.

İki Farklı Döner Nikel-Titanyum Preparasyon Sistemi Ve İki Farklı El Preparasyon Sisteminin Eğimli Kök Kanallarının Şekillendirilmesindeki Etkinliklerinin Karşılaştırılması

Amac: Bu calismanin amaci, Quantec LX ve Profile 29 doner NiTi enstrumanlar ve Nitiflex ve paslanmaz celik el enstrumanlarinin egri kanallardaki etkinliginin karsilastirilmasidir. Gerec ve Yontem: Bu calismada 25-40° kurvatur acisina sahip 48 adet mandibular molar dise ait mesial kanallar, her biri 12 kanal icerecek sekilde 4 gruba ayrildi. Preparasyon gruplari olarak Nitiflex ve H tipi el enstrumanlari, Profile 29 ve Quantec LX doner NiTi enstrumanlar kullanildi. Calismanin sonunda kanal egiminde ve calisma boyunda meydana gelen degisiklikler, alet kiriklari ve perforasyonlar kaydedildi. Verilerinin istatistiksel olarak degerlendirilmesinde Wilcoxon eslestirilmis iki ornek testi, Kruskal-Wallis ve Mann Whitney-U testleri kullanildi. Bulgular: Doner NiTi preparasyon sistemlerinin kanal egiminde ve calisma boyunda paslanmaz celik kanal egelerine gore daha az degisime neden oldugu saptandi. Paslanmaz celik ve Nitiflex kanal egelerinde alet kirigi saptanmadi. Doner NiTi preparasyon sistemlerinde lateral perforasyonlar gorulurken, paslanmaz celik kanal egesi kullanilan grupta ise strip perforasyonlar saptandi. Sonuclar: Sonuc olarak, doner NiTi preparasyon sistemlerinin egri kok kanallarini, elle kullanilan preparasyon sistemlerine gore daha etkili bir sekil