Evaluating root and canal configuration of mandibular first molars with cone beam computed tomography in a Turkish population

Background/purpose: During root canal therapy, third roots of mandibular first molars (MFMs) provide an important route for bacterial leakage that can lead to root canal treatment failure and the need for additional surgical intervention. Therefore, the aim of this study was to investigate root and canal morphology of permanent MFMs in a Turkish population using cone beam computed tomography (CBCT)

Effects of ethylenediaminetetraacetic acid and sodium hypochlorite on the bond strength of bonding agents to pulp chamber lateral walls

Barutcugil, Cagatay/0000-0002-5321-2299; harorli, osman tolga/0000-0001-6828-5063WOS: 000342263000004Background/purpose: The purposes of this in vitro study were to determine the microtensile bond strengths of four different dentin adhesive materials placed in pulp chamber walls, and to test the effects of 5% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA) pretreatments on resin dentin bond strengths. Materials and methods: Recently extracted human third molars were selected. The teeth were divided into four groups. Specimens in each group were treated as follows: irrigated with distilled water; irrigated with EDTA for 5 minutes; irrigated with sodium hypochlorite for 5 minutes; and irrigated with EDTA for 5 minutes followed by NaOCl. for 5 minutes. Treated specimens were dried, bonded with a total-etching adhesive, two self-etching adhesives, or a one-bottle self-etching adhesive system. After the bonding procedure and composite restoration, teeth were sectioned, and 15 dentin sticks were obtained. Microtensile testing was performed, and scanning electron micrographs were taken of each irrigated group. Results: In the control group, the one-bottle self-etching adhesive system showed statistically higher bond strength values. EDTA irrigation did not affect the bond strength except for the total-etching adhesive. NaOCl significantly reduced the bond strengths of all adhesives. The EDTA and NaOCl combination did not show a statistically significant reduction in bond strengths of the adhesives to pulpal dentin. Conclusion: There was a reduction in bond strengths of all adhesive systems used to test pulp chamber lateral walls after endodontic irrigation solutions were used. Copyright (C) 2012, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved

The color differences of direct esthetic restorative materials after setting and compared with a shade guide

harorli, osman tolga/0000-0001-6828-5063; Barutcugil, Cagatay/0000-0002-5321-2299; BAYINDIR, FUNDA/0000-0001-5699-2879WOS: 000291844800019PubMed: 21628688Background. The authors conducted a study to evaluate esthetic restorative materials' color differences after setting and color matching between set materials and a shade guide. Materials and Methods. The authors evaluated 13 resin-based composites, one silorane-based composite, two polyacid-modified resin composites and one conventional glass ionomer cement. They measured the color parameters of the samples, which were 8 millimeters in diameter and 1 5 mm in thickness, before and after they were set according to the Commission International de l'Eclairage (CIE) L*a*b* color scale relative to standard illumination against a white background by means of a dental colorimeter. They also compared the final colors of the restorative materials with a shade guide. Results. Color difference values for each restorative material ranged from 3.25 to 14.04. With the exception of Fuji IX (GC, Tokyo), Filtek P60 (3M ESPE) and Te-Econom (Ivoclar Vivadent), the restorative materials exhibited a perceptible color change after setting. Color difference values between the set materials and the shade guide tabs ranged from 1.86 to 11.83. With the exception of Filtek Supreme XT (3M ESPE) and Fuji IX, the materials exhibited a perceptible difference. Conclusion. Most of the materials tested exhibited a significant color change after polymerization and did not match the shade guide tab after undergoing light curing.Ataturk University Research FundAtaturk University [2003/158]This study was supported partially by Ataturk University Research Fund (project 2003/158)

Push-Out Bond Strength Between Composite Core Buildup and Fiber-Reinforced Posts After Different Surface Treatments

Objective: The aim of this study was to evaluate the effects of different surface treatments on the pushout bond strength of fiber-reinforced posts to composite resin cores. Materials and methods: Twenty-five translucent glass fiber posts were divided into five groups according to surface treatment methods as follows: an untreated control group, a group coated with silicated alumina particles (Co-Jet system, 3M ESPE, St. Paul, MN), and three groups undergoing surface preparation with erbium: yttrium-aluminum-garnet (Er:YAG) laser under three different power settings (150, 300, and 450 mJ at 10 Hz for 60 sec at 100 mu s duration). After surface treatment, fiber posts were built up to a dual cure composite resin core. All of the specimens were set and sectioned perpendicularly along the long axis of the post using a saw. Two discs (thickness of 2 mm) were obtained from each post-core sample; finally, each group consisted of 10 samples. For artificial aging, the specimens were stored in water (37 degrees C) for 24 h and subjected to thermal cycling (5000 cycles, 5-55 degrees C, and 30 sec dwell time). Pushout tests were performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The pushout pressure values were measured in MPa and analyzed using one way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) post-hoc test (p < 0.05). Fiber post surface images were obtained using a scanning electron microscope (SEM). Results: The bond strength values ranged between 14,949 and 23,879 MPa. The lowest values were observed in the groups treated with the Er:YAG laser at 150 mJ. Irradiation by the Er:YAG laser at 450 mJ affected the bond strength significantly (p < 0.05). After Co-Jet sandblasting, the bond strength increased relatively (19,184 MPa). Conclusions: Er:YAG laser irradiation enhanced the bond strength of fiberre-inforced posts to composite resin cores depending upon the power applied; Co-Jet sandblasting also increased the bond strength

Efficacy of different treatments of root canal walls on the pull-out bond strength of the fiber posts

The aim of this study was to evaluate the efficacy of different irrigation protocols, including laser, on the retention of the fiber-reinforced composite posts to root canal dentinal walls using pull-out tests. Root canals of 60 single-rooted human teeth were filled and post spaces were prepared. Finally, specimens were divided randomly into five groups, each consisting of 12 specimens as follows: 5 % NaOCl (control group), 17 % EDTA, ultrasonic with 17 % EDTA, single 1.5-W Er:YAG laser application, and the combined use of Er:YAG laser and 17 % EDTA. After the root canal procedures, fiber posts were cemented to the root canal. Pull-out tests were performed using a universal testing machine at a crosshead speed of 2 mm/min. The data were analyzed using a one-way ANOVA and Bonferroni post hoc test (p = 0.05). Irradiation by the Er:YAG laser with/without EDTA positively affected the pull-out bond strength (p < 0.001). The pull-out strength was significantly higher in the ultrasonic group than that of the single irrigation with NaOCl or EDTA (p < 0.001). Er:YAG laser irradiation with/without EDTA enhanced the bond strength of fiber posts to root canal dentin walls. Additionally, ultrasonic-EDTA combination increased the bond strength

Effects of post surface treatments including Er:YAG laser with different parameters on the pull-out bond strength of the fiber posts

This study aims to evaluate the effects of Er:YAG laser irradiation under different power settings on the pull-out bond strengths of fiber-reinforced composite posts. The crowns of single-rooted 60 teeth were removed by separation and the root canals were cleaned and shaped. Root canals were filled and post spaces were prepared. Sixty fiber posts were divided into five groups according to surface treatment methods as follows: an untreated control group, a sandblasting-coated group, and three groups undergoing surface preparation with Er:YAG laser under three different power settings (150, 300, and 450 mJ at 10 Hz for 60 s at 100-mu s pulse duration). After root canal procedures, fiber posts were cemented to the root canal. After all of the specimens were set, pull-out tests were performed using a universal testing machine at a crosshead speed of 2 mm/min. The data were analyzed using one-way ANOVA and Tukey post-hoc test (p < 0.05). The pull-out strength values ranged between 5.26 and 6.76 Mpa. The lowest values were observed in the groups without surface treatment. Surface treatment applied by 4.5-W Er:YAG laser increased the pull-out bond strength compared to the control group (p < 0.05). 4.5-W Er:YAG laser irradiation increased the pull-out bond strength of fiber posts to resin cement