Search

Background and Objective: Little is known about the correspondence of cytokines detected among the different biological matrices used in periodontal research and whether locally-detected cytokine mRNA can also be identified at the translated protein level. The aims of this study were to compare: (a) the detection of classic cytokines at protein level in corresponding samples of serum, gingival tissue and gingival crevicular fluid (GCF) in subjects with periodontitis and (b) the detection of cytokines at protein level in GCF and tissue with their detection at mRNA level in tissue., Material and Methods: Protein concentrations of IL-1β, IL-6 and TNF-α were measured in corresponding samples of GCF, gingival tissue and serum from 125 subjects with chronic periodontitis by multiplex immunoassay. The mRNA levels of these cytokines were evaluated in the same gingival tissue by qPCR., Results: The mean protein concentrations of IL-1ß and TNF-α were higher in tissue and GCF than in serum (P < 0.05). The mean protein concentration of IL-6 was higher in tissue, followed by serum and GCF, respectively (P < 0.05). Using serum as the gold standard, detection of IL-1ß in GCF and IL-6 in tissue had the highest sensitivity (100%), while detection of IL-6 in the GCF had the lowest sensitivity (77.9%). Using tissue as the gold standard, the detection sensitivities of IL-1ß, IL-6 and TNF-α were 93.6%, 78.4% and 94.2%, respectively, in GCF. Using mRNA as the gold standard, the detection of IL-1ß and IL-6 at the protein level in tissue (100.0%) had the highest sensitivity, while the detection of IL-6 in GCF (77.9%) had the lowest sensitivity., Conclusion: Tissue and GCF exhibited overall higher protein concentrations of cytokines than serum. GCF presented good reliability for identifying the target cytokines at protein level, when compared with detecting tissue cytokines at protein level. GCF and tissue presented high sensitivities for detecting cytokines at the protein level, when compared with detecting tissue cytokines at the mRNA level. The sensitivity for the identification of cytokines in the GCF depended on the target cytokine, where IL-6 was the least likely cytokine to be detected in this matrix., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: To evaluate the bond strength between two types of acrylic resin teeth and a microwave denture base resin after immersion in disinfectant solutions for 180 days., Materials and Methods: Eighty specimens made of acrylic resin teeth (Biotone and Biotone IPN) attached to a microwave polymerized denture base resin (Nature-Cryl MC) were divided into eight groups (n = 10) according to the treatment (distilled water-control, 2% chlorhexidine digluconate, 1% sodium hypochlorite and sodium perborate solution-Corega Tabs). The shear strength tests (MPa) were carried out using a universal testing machine with a 0.5 mm/min speed. Data analysis was performed using ANOVA and multiple comparison Student-Newman-Keuls post hoc test (α = 0.05)., Results: Biotone IPN showed similar results among the groups (distilled water, 8.25 ± 1.81 MPa; chlorhexidine, 7.81 ± 3.34 MPa; hypochlorite, 7.75 ± 3.72 MPa; and Corega Tabs, 7.58 ± 2.27 MPa, whereas Biotone showed significantly lower shear bond strength values for the groups immersed in Corega Tabs (5.25 ± 3.27 MPa) and chlorhexidine (6.08 ± 2.35 MPa)., Conclusions: Soaking the dentures in 1% sodium hypochlorite could be recommended as a disinfectant solution for dentures fabricated with conventional acrylic resin denture teeth and microwave denture base resin. For dentures fabricated with IPN teeth and microwave denture base resin, all the soaking solutions evaluated in this study could be suggested to denture wearers., (© 2015 by the American College of Prosthodontists.)

Purpose: To assess the effect of brushing with different solutions on the abrasion resistance of two types of acrylic resin teeth., Materials and Methods: Maxillary premolars from two types of acrylic teeth (Biotone and Biotone IPN) were divided into six groups (n = 12), according to the solution used during brushing: distilled water (control), coconut soap, or dentifrice. A mechanical brushing machine was used to simulate approximately 1 year of brushing (11,000 strokes). The weight loss (WL) of teeth was obtained from the difference between the initial (IW) and final weight (FW) of each specimen, and the mean of percentage of weight loss (PWL) was calculated for each group. Data were analyzed using the Kruskal-Wallis test, followed by Bonferroni's post-test comparison (α = 0.05)., Results: A statistically significant difference was found for the factor solution (p < 0.001). Brushing using dentifrice caused the highest values of weight loss (-0.50%), in comparison with the groups brushed with coconut soap (0.00%) or distilled water (0.00%)., Conclusions: For both types of artificial teeth, brushing with dentifrice produced higher abrasion than brushing with coconut soap or water., (© 2016 by the American College of Prosthodontists.)

Purpose: The objectives of this study were to investigate the flexural strength (FS) and chemical interaction between 2-tert-butylaminoethyl methacrylate (TBAEMA) and a denture base acrylic resin., Materials and Methods: Specimens were divided into five groups according to the concentration of TBAEMA incorporated in acrylic resin Onda-Cryl (0%, 1%, 2%, 3%, 4%) and were submitted to Fourier transform infrared spectroscopy (FTIR), electron spectroscopy for chemical analysis (XPS-ESCA), and differential scanning calorimetry (DSC) analyses. FS of the specimens was tested, and results were analyzed by ANOVA/Tukey's test (α < 0.05)., Results: Different nitrogen ratios were observed on specimens' surfaces: 0.36%, 0.54%, 0.35%, and 0.20% for groups 1%, 2%, 3%, and 4%, respectively. FTIR indicated copolymerization of acrylic resin and TBAEMA, and DSC results demonstrated a decrease in glass transition temperature (Tg ). Significant differences were found for FS (p < 0.05). The mean values were 91.1 ± 5.5,(A) 77.0 ± 13.1,(B) 67.2 ± 12.5,(B) 64.4 ± 13.0,(B) and 67.2 ± 5.9(B) MPa for groups 0%, 1%, 2%, 3% and 4%, respectively (same superscript letters indicate no significant difference)., Conclusions: The incorporation of TBAEMA in acrylic resin resulted in copolymerization and the presence of amine groups on specimens' surfaces, and in decreases of Tg and FS., (© 2012 by the American College of Prosthodontists.)