Dilara Arslan

Tissue Dissolution Ability of Sodium Hypochlorite Activated by Photon-initiated Photoacoustic Streaming Technique

INTRODUCTION The aim of this study was to evaluate the effect of the photon-initiated photoacoustic streaming (PIPS) technique on the pulp tissue-dissolving capacity of sodium hypochlorite (NaOCl) and compare it with the EndoActivator System (Dentsply Tulsa Dental Specialties, Tulsa, OK) and the Er:YAG laser with an endodontic fiber tip. METHODS Bovine pulp tissue samples (45 ± 15 mg) and dentin powder (10 mg) were placed in 1.5-mL Eppendorf tubes with 1 mL 5.25% NaOCl (Wizard; Rehber Kimya, Istanbul, Turkey) or distilled water (control) for 5 minutes with activation by the EndoActivator System, the Er:YAG laser with an endodontic fiber tip, and the PIPS technique. Nonactivated NaOCl served as the positive control. All testing procedures were performed at room temperature. The tissue samples were weighed before and after treatment, and the percentage of weight loss was calculated. The differences were statistically analyzed. RESULTS The highest rate of tissue dissolution was observed in the NaOCl + Er:YAG group (P < .05). The NaOCl + PIPS group dissolved more bovine pulp tissue than the nonactivated NaOCl group (P < .05). There was no statistically significant difference between the rates of tissue dissolution of the NaOCl + EA and the nonactivated NaOCl groups (P > .05). CONCLUSIONS NaOCl activation with the Er:YAG laser with an endodontic fiber tip was the most effective in bovine pulp tissue dissolution. The PIPS technique also promoted superior tissue-dissolving effects when compared with no activation. However, the EndoActivator System had no direct effect on tissue dissolution.

Effects of three different irrigating solutions and KTP laser irradiation on apical leakage: An electrochemical study

Abstract Objective. The purpose of this study was to evaluate the effect of three different irrigating solutions (17% EDTA, 10% citric acid and 2.5% NaOCl) and KTP laser irradiation on apical leakage using an electrochemical method. Materials and methods. Sixty extracted single-rooted human teeth with mature apices were instrumented up to a size 35 K-file. After using each file and before proceeding to the next, canals were irrigated with 2 ml of 2.5% NaOCl. All teeth were then randomly divided into four groups. In group 1, the root canals were irrigated with a final flush of 17% EDTA. In group 2, the root canals were irrigated with a final flush of 10% citric acid. In group 3, the root canals were irradiated with KTP laser at 1 W, 4.45 J/cm2. In group 4, the root canals were irrigated with a final flush of 2.5% NaOCl. The root canals were then filled using the cold lateral condensation method. Apical leakage was evaluated using an electrochemical method over a period of 10 days. Data were analysed using Tukey HSD and Friedmann tests with p = 0.05 as the level for statistical significance. Results. The 17% EDTA and 10% citric acid groups had statistically less apical leakage than the 2.5% NaOCl group at days 7, 8, 9 and 10 (p < 0.05); however, no significant differences were found between the tested groups at the other time intervals (p > 0.05). No significant difference was found between the KTP laser group and other groups tested at all time intervals (p > 0.05). Conclusion. All groups were unable to eliminate apical leakage. However, final irrigation with 17% EDTA and 10% citric acid following root canal preparation reduced postobturation apical leakage compared with 2.5% NaOCl irrigation. When KTP laser and the other three irrigants were compared, no siginificant difference was found.

Pulp tissue dissolution capacity of QMix 2in1 irrigation solution.

Objective: The aim of this study was to evaluate the tissue dissolution efficacy of four root canal irrigation solutions (sodium hypochlorite [NaOCl], chlorhexidine gluconate [CHX], Octenidine [OCT], and QMix 2in1) on bovine pulp tissue. Materials and Methods: Fifty bovine pulp tissue samples, each weighing 6.55 mg, were prepared and randomly divided into four experimental groups and one control group (n = 10) according to the dissolution irrigants used: (1) 5.25% NaOCl group; (2) 2% CHX group; (3) OCT group; (4) QMix 2in1 group; and (5) control group (saline solution). These samples were then placed into special bovine dentin reservoir models and immersed for 1 h with each test solution (0.1 mL of each) at room temperature. The pulp samples were then blotted dry and weighed again. The percentage of weight loss was calculated. Statistically analyzed with one-way analysis of variance and post-hoc Tukey tests (P = 0.05). Results: Saline solution did not dissolve the bovine pulp tissue. All groups, except OCT, dissolved pulp samples more effectively than the control group (P < 0.05). The highest tissue dissolution was observed in 5.25% NaOCl group (P < 0.05). No statistically significant difference was found between the tissue-dissolving effect between QMix 2in1 and those of 2% CHX. Conclusions: Within the limitations of this in vitro study, NaOCl exhibited the best tissue-dissolving effect out of all solutions tested. CHX and QMix 2in1 were able to dissolve pulp tissue but less than NaOCl. OCT and saline solutions could not exhibit significantly tissue-dissolving effectiveness. This study shown that QMix 2in1 has little capacity to dissolve pulp tissue therefore used alone is not sufficient for this purpose.

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.

Apical extrusion of debris during root canal preparation using a novel nickel-titanium file system: WaveOne gold

Aim: This study was intended to evaluate the amount of apically extruded debris following root canal preparation with three different instrumentation systems. Materials and Methods: Sixty mandibular incisor teeth were selected and randomly divided into three groups (n = 20/group) according to the instrumentation system used: the ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), the Twisted File Adaptive (TFA; SybronEndo, Orange, CA, USA), and the WaveOne Gold (WOG; Dentsply Maillefer, Ballaigues, Switzerland). All apically extruded debris was collected and dried in preweighed glass vials. The mean weight of the apically extruded debris was obtained using a microbalance. The time for root canal preparation was also recorded. The data were analyzed using a one-way analysis of variance. Results: The mean weights of apically extruded debris were 0.00035 ± 0.00014 g (PTN); 0.00023 ± 0.0001 g (TFA); and 0.00019 ± 0.0001 g (WOG) (P < 0.01). The mean preparation time value was 301,13 ± 62.14 s (PTN); 234.27 ± 34.88 s (TFA); and 239.8 ± 58.6 s (WOG) (P < 0.05). Conclusions: The PTN system extruded more debris than the TFA and WOG systems. The TFA and WOG systems were faster than the PTN system.

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.