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Bonferroni Post Hoc Test (bonferroni + post_hoc_test)
Selected AbstractsBonding to Zirconia Using a New Surface TreatmentJOURNAL OF PROSTHODONTICS, Issue 5 2010Moustafa N. Aboushelib DDS Abstract Purpose: Selective infiltration etching (SIE) is a newly developed surface treatment used to modify the surface of zirconia-based materials, rendering them ready for bonding to resin cements. The aim of this study was to evaluate the zirconia/resin bond strength and durability using the proposed technique. Materials and Methods: Fifty-four zirconia discs were fabricated and divided into three groups (n = 18) according to their surface treatment: as-sintered surface (control group), airborne-particle abrasion (50-,m aluminum oxide), and SIE group. The zirconia discs were bonded to preaged composite resin discs using a light-polymerized adhesive resin (Panavia F 2.0). The zirconia/resin bond strength was evaluated using microtensile bond strength test (MTBS), and the test was repeated after each of the following intervals of accelerated artificial aging (AA): thermocycling (10,000 cycles between 5 and 55°C), 4 weeks of water storage (37°C), and finally 26 weeks of water storage (37°C). Silver nitrate nanoleakage analysis was used to assess the quality of zirconia/resin interface. A repeated measures ANOVA and Bonferroni post hoc test were used to analyze the data (n = 18, ,= 0.05) Results: There were significant differences in the MTBS values between the three test groups at each of the test intervals (p < 0.001). AA resulted in reduction in the bond strength of the as-sintered and the particle-abraded groups (5.9 MPa and 27.4, MPa, respectively). Reduction in the bond strength of these groups was explained by the observed nanoleakage across the zirconia/resin interface. The bond strength of the SIE specimens was stable after completion of AA (51.9 MPa), which also demonstrated a good seal against silver nitrate penetration across the zirconia/resin interface. Conclusion: SIE established a strong, stable, and durable bond to zirconia substrates. Conservative resin-bonded zirconia restorations are now possible using this new technique. [source] Effect of Net Fiber Reinforcement Surface Treatment on Soft Denture Liner Retention and LongevityJOURNAL OF PROSTHODONTICS, Issue 4 2010MPhil, Muhanad M. Hatamleh BSc Abstract Purpose: To evaluate shear bond strength of Molloplast-B soft liner attached to different acrylic surfaces (smooth, rough, and Sticktech net fiber-reinforced interfaces) after 3000 thermal cycles. Materials and Methods: Sixty-nine specimens were fabricated by attaching Molloplast-B soft liner to acrylic bases of three interfaces (n= 23); smooth (Group 1, control), rough (Group 2), and Sticktech net fiber-reinforced interface (Group 3). The specimens underwent 3000 thermocycles (5 and 55°C) before being subject to a shear bond test at 2 mm/min crosshead speed. Debonding sites were investigated using an optical microscope at 40× magnification. Bond failures were categorized as adhesive, cohesive, or mixed. Results: Mean (SD) bond strength values (MPa) were: 0.71 (0.15); 0.63 (0.07); and 0.83 (0.12) for smooth, rough, and fiber-reinforced acrylic interfaces, respectively. The mean values were analyzed using one-way ANOVA and Bonferroni post hoc test for pairwise comparisons (p, 0.05). The net fiber-reinforced acrylic interface exhibited a statistically significantly higher bond strength value when compared to smooth and rough acrylic interfaces (P= 0.003 and P= 0.000, respectively). Modes of failure were mainly cohesive (91%), followed by mixed failures (9%). Conclusions: Molloplast-B exhibited a stronger bond to StickTech Net fiber-reinforced surfaces when compared to smooth and rough acrylic interfaces after thermocycling. This may enhance prosthesis serviceability during clinical use. [source] Effects of thiol compounds on in vitro maturation of canine oocytes collected from different reproductive stagesMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 9 2007Mohammad Shamim Hossein Abstract Various thiol compounds are known to improve cytoplasmic and/or nuclear maturation of oocytes in vitro. The present study examined the effects of two thiol compounds, cysteine (0.1, 0.5, and 1.0 mM) and cysteamine (50, 100, and 200 µM), on cytoplasmic and nuclear maturation of canine oocytes. Oocytes collected from different reproductive stages were cultured in TCM-199 supplemented with 10% fetal bovine serum, 2.2 mg/ml sodium carbonate, 2.0 µg/ml estrogen, 0.5 µg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin,streptomycin solution for 72 h. Data were analyzed by two-way ANOVA after arcscine transformation and protected by Bonferroni post hoc test. The effects of cysteine and cysteamine on canine IVM were varied depending on the reproductive stage of oocyte donor bitches. In the follicular stage, significantly more oocytes reached the metaphase II (M II) stage when cultured with 0.5 or 1.0 mM cysteine (16.7% and 16.9%, respectively) compared to the control (6.2%). In the follicular stage, cysteamine increased oocyte maturation rate upto the M II stage (15.1% to 17.0%) compared to the control (4.4%). Both the 0.5 mM cysteine and 100 µM cysteamine, alone or together, increased the intracellular GSH level of canine oocytes compared to the control. Irrespective of reproductive stage, no further beneficial effects on nuclear or cytoplasmic maturation were observed when 0.5 mM cysteine and 100 µM cysteamine were supplemented together. In conclusion, addition of 0.5 mM cysteine and 100 µM cysteamine to the maturation medium improved IVM of canine oocytes. Mol. Reprod. Dev. 74: 1213,1220, 2007. © 2007 Wiley-Liss, Inc. [source] Mood and anxiety psychopathology and temporomandibular disorder: a spectrum approachJOURNAL OF ORAL REHABILITATION, Issue 10 2004D. Manfredini summary, Psychological factors play an important role in the aetiopathogenesis of temporomandibular disorders (TMD), as demonstrated by an increase in stress, anxiety, depression and somatization in TMD patients. The aim of this work was to investigate the presence of mood and panic-agoraphobic symptoms in different groups of TMD patients by means of a spectrum approach to psychopathology. A total of 131 subjects were included in this study and TMD signs and symptoms were investigated by means of a standardized clinical examination. Two self-report questionnaires were used to evaluate mood (MOODS-SR) and panic-agoraphobic (PAS-SR) spectrum. anova and Bonferroni's post hoc test for multiple comparisons were used to compare mean scores of all TMD groups for MOODS-SR, PAS-SR and all their domains. Results revealed a significantly higher prevalence of both mood (P < 0·001) and panic-agoraphobic (P < 0·01) symptoms in myofascial pain patients than in all other diagnostic groups (TMD-free, disc displacement and joint disorders). With regard to mood spectrum, strong differences emerged for all domains evaluating depressive symptoms. As for the panic-agoraphobic spectrum, myofascial pain patients differed from the other groups for the presence of stress sensitivity, panic, separation anxiety, hypochondriac and agoraphobic symptoms. It was concluded that myofascial pain patients differed from those with disc displacement, joint disorders and no TMD in relation to some psychopathological symptoms, while the last three groups presented very similar profiles. [source] | ||||||||||