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The aim of this study was to evaluate the bond strength between the fibre post and root dentin after different cleaning protocols to remove eugenol from dentin. The residues and elemental composition of dentin were analysed using SEM and EDS. Bovine incisor roots were obturated with eugenol-based sealer. The post space was prepared, and the roots were divided into the following groups according to the cleaning protocol: unfilled (negative control), saline solution (positive control), 70% ethanol, acetone and 70% isopropyl alcohol. The fibre posts were cemented and push-out test realised. Chemical analysis of the dentin was performed using SEM and EDS. The bond strength values were analysed by anova/Fisher's and were as follows: negative control (7.30 ± 2.77) = 70% ethanol (6.64 ± 2.91) = 70% isopropyl alcohol (5.01 ± 3.15) = acetone (4.42 ± 1.53) >positive control (1.29 ± 0.56). It was concluded that 70% ethanol may be a good cleaning protocol to remove eugenol from dentin., (© 2018 Australian Society of Endodontology Inc.)

Objective: This study aimed to perform an epidemiological survey of the cases of oral lesions diagnosed in a Brazilian dental school., Materials and Methods: An epidemiological survey was carried out at the Faculty of Dentistry of the University of Passo Fundo (FOUPF), Rio Grande do Sul, Brazil, between March 2015 and June 2017, characterizing the patients in terms of gender, age, and ethnicity. A total of 3,200 records were evaluated, from which 716 presented information on oral lesions diagnosed and treated at the clinics of the FOUPF. The data were evaluated by descriptive statistics of frequency., Results: The most frequent change was the coated tongue (13.83%). The majority of the patients were female (56%), white (31.57%), in the sixth decade of life (21.65%). Regarding the classification of lesions, the most frequent group was developmental changes (25%)., Conclusion: It is considered that the sample studied presented a significant index of oral lesions and normality changes, considering that 716 (22.38%) patients studied showed some type of change in the oral cavity., Clinical Significance: The sample studied presents peculiar characteristics regarding the number of oral lesions/conditions diagnosed. It is also considered that Schools of Dentistry are valuable environments for carrying out epidemiological surveys in stomatology, providing the diagnostic exercise, as long as the students are stimulated for this purpose.

Purpose: To evaluate the influence of subcutaneous injection nicotine in osseointegration process on different implant surfaces., Methods: Twenty-two male rabbits were distributed into two groups according to the subcutaneous injections: (1) nicotine 3 mg/day/kg and (2) 0.9 % NaCI 3 mL/day/kg, three times a day; subgroups were then designated-machined and anodized implants were placed in the right and left tibia bones, respectively. The animals were submitted euthanasia after periods of eight weeks to determine nicotine and cotinine levels, alkaline phosphatase and biomechanical analysis., Results: The plasmatic levels of nicotine and cotinine were 0.5 ± 0.28 ng/mL and 9.5 ± 6.51 ng/mL, respectively. The alkaline phosphatase analyses in blood levels in control group were observed 40.8 ± 11.88 UI/L and 40.75 ± 12.46 UI/L, for the surfaces machined and anodized, respectively. In the test group was observed levels 37.9 ± 4.84 UI/L, for both implant surfaces. No significant differences were observed between control and test groups and between the implant surfaces regarding alkaline phosphatase blood levels. For biomechanics, no significant differences were observed in control group between the machined (25±8.46 Ncm) or anodized (31.2 ± 6.76 Ncm) implants. However, the treatment with nicotine induced higher torque than control in both machined (38.3 ± 13.52 Ncm) and anodized (35.5 ± 14.17 Ncm) implants, with p = 0.0024 and p = 0.0121, respectively., Conclusion: Subcutaneous injection of nicotine following implant insertion didn't have effect on osseointegration, independently from the implant surface.

Purpose: To evaluate the influence of irrigation protocols and drying procedures on the bond strength of two methacrylate-based sealers to dentin and the associated failure pattern using scanning electron microscopy (SEM)., Materials and Methods: Fifty single-rooted human teeth were prepared with an irrigation protocol using either 5.25% sodium hypochlorite (NaOCl) or 2% chlorhexidine (CHX) and 17% EDTA (ethylenediaminetetraacetic acid) for smear layer removal. The following subgroups were also created based on drying of the root canal walls: paper points, the canals were blot dried with paper points with the last one appearing dry; or, ethanol, excess distilled water was removed with paper points followed by dehydration with 95% ethanol for 1 min and blotting with paper points. Each group was divided into two subgroups on the basis of the root canal sealer: EndoREZ and RealSeal SE. Bond strength was measured by the push-out test. The data were analyzed by ANOVA/Tukey HSD (α = 0.05). Failure patterns were classified as adhesive, cohesive, and mixed in the SEM analysis. The failure mode was evaluated by the chi-squared test (α = 0.05)., Results: The roots irrigated with NaOCl showed significantly lower bond strength than the roots irrigated with CHX (p < .05). RealSeal SE showed higher bond strength when compared with EndoREZ (p < .05). The highest values of bond strength were in the CHX and ethanol groups with RealSeal SE (p < .05). An increase in adhesive failure was observed in the NaOCl and EDTA group., Conclusions: The bond strength of both methacrylate-based sealers is influenced by the irrigant protocol., (© 2017 Wiley Periodicals, Inc.)

Aim: The aim of this study was to evaluate the effectiveness of final decontamination protocols against Enterococcus faecalis and their influence on bond strength of filling material to root canal dentin., Material and Methods: Ninety root canals were enlarged with ProTaper system and inoculated with E. faecalis for 15days. Sixty samples were randomly divided into six groups (n=10) and subjected to following protocols: G1-distilled water(control), G2-2% chlorhexidine, G3-QMix, G4-6.5% grape seed extract, G5-photodynamic therapy with optical fiber and G6-photodynamic therapy without optical fiber. The percentage of bacterial reduction was checked by counting of CFUs. The remaining 30 samples were subjected to the same decontamination protocols (n=5) and filled with gutta-percha and AH Plus sealer in order to perform the push-out test. Data from both tests were subjected to one-way ANOVA followed by Tukey's post hoc procedure (α=0.05)., Results: The greatest bacterial reduction was observed for 2% chlorhexidine, QMix and 6.5% grape seed extract, with no statistically significant difference between them. Photodynamic therapy, with and without optical fiber, demonstrated a significantly higher reduction than distilled water, with no statistically significant difference between them (p<0.05). For the push-out test, final decontamination protocols showed similar bond strength values (p<0.05), with the highest incidence of cohesive failure in all groups., Conclusions: The tested final decontamination protocols showed effectiveness against E. faecalis and did not interfere with the bond strength of filling material to root canal dentin., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Purpose: The aim of this study was to evaluate the influence of cement type and relining procedure on push-out bond strength of fiber posts (FPs) after cyclic loading., Materials and Methods: Forty bovine incisor roots were divided into four groups: group 1, FP luting with RelyX Unicem; group 2, FP relined with resin composite (FPC) luting with RelyX Unicem; group 3, FP luting with RelyX ARC; group 4, FPC luting with RelyX ARC. Afterwards, half the specimens were exposed to 250,000 cycles in a controlled chewing simulator. With the other half of the specimens in each group, the push-out test was performed 24 hours after FP luting (immediate groups). All roots were sectioned transversely, producing 1-mm-thick slices, and the push-out test was performed. Statistical analysis was performed using ANOVA and the Tukey test for post hoc comparisons (α = 0.05)., Results: FPC had higher bond strengths than FP (p < 0.05). RelyX Unicem showed higher bond strength than RelyX ARC (p < 0.05). Cyclic loading did not significantly affect the bond strength value (p > 0.05)., Conclusion: The relining procedure and the cement type are important factors for the bond strength of FPs to root dentin., (© 2015 by the American College of Prosthodontists.)

Aim: The aim of this study was to investigate the influence of cleaning methods to remove zinc oxide-eugenol-based root canal sealer (Endomethasone) on the bond strength of the self-etching adhesive to dentin., Materials and Methods: Twenty crowns of bovine incisors were cut to expose the pulp chamber. A zinc oxide- and eugenol-based sealer was placed for 10 min in contact with the pulp chamber dentin. Specimens were divided into four groups according to the cleaning method of dentin used: G1, no root canal sealer (control); G2, 0.9% sodium chlorite (NaCl); G3, ethanol; and G4, followed by diamond drill. After cleaning, the teeth were restored with composite resin and Clearfil SE Bond. All specimens were sectioned to produce rectangular sticks and dentin/resin interface was submitted to microtensile bond testing. The mean bond strengths were analyzed using ANOVA/Tukey (α = 0.05)., Results: G3 and G4 showed bond strengths similar to the G1 (P > 0.05). A significant decrease in the bond strength in the G2 was observed (P < 0.05). G1, G3, and G4, the predominant failure mode was the mixed type. The prevalence of adhesive failure mode was verified in the G2., Conclusion: The cleaning methods affected the bond strength of the self-etching adhesive to dentin differently.

Introduction: The purpose of this study was to compare in vitro the effectiveness of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with passive ultrasonic irrigation in root canals of bovine teeth infected with Enterococcus faecalis., Methods: The root canals of 60 single-rooted bovine extracted teeth were enlarged up to a file 45, autoclaved, inoculated with Enterococcus faecalis, and incubated for 30 days. The samples were divided into 6 groups (n = 10) according to the protocol for decontamination: G1: no treatment; G2: distilled water; G3: 2.5% NaOCl; G4: 2.5% Ca(OCl)2; G5: 2.5% NaOCl with ultrasonic activation; and G6: 2.5% Ca(OCl)2 with ultrasonic activation (US). Microbiological testing (colony-forming unit [CFU] counting) was performed to evaluate and show, respectively, the effectiveness of the proposed treatments. Data were subjected to 1-way analysis of variance followed by the post hoc Tukey test (α = 0.05)., Results: Groups 1 and 2 showed the highest mean contamination (3.26 log10 CFU/mL and 2.69 log10 CFU/mL, respectively), which was statistically different from all other groups (P < .05). Group 6 (Ca[OCl]2 + US) showed the lowest mean contamination (1.00 log10 CFU/mL), with no statistically significant difference found in groups 3 (NaOCl), 4 (Ca[OCl]2), and 5 (NaOCl + US) (P < .05)., Conclusions: Ca(OCl)2 as well as passive ultrasonic irrigation can aid in chemomechanical preparation, contributing in a significant way to the reduction of microbial content during root canal treatment., (Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)