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Tukey's Post Hoc Test (tukey + post_hoc_test)
Selected AbstractsCytotoxicity and genotoxicity of sodium percarbonate: a comparison with bleaching agents commonly used in discoloured pulpless teethINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2010M. R. Fernández Fernández MR, Carvalho RV, Ogliari FA, Beira FA, Etges A, Bueno M. Cytotoxicity and genotoxicity of sodium percarbonate: a comparison with bleaching agents commonly used in discoloured pulpless teeth. International Endodontic Journal, 43, 102,108, 2010. Abstract Aim, To evaluate the cytotoxicity and genotoxicity of sodium percarbonate (SPC) in comparison with bleaching agents used on discoloured pulpless teeth. Methodology, The cytotoxicity and genotoxicity of bleaching agents were evaluated both in their pure form as well as at concentrations commonly used in clinical practice. Hydrogen peroxide (HP), carbamide peroxide (CP), sodium perborate (SP) and SPC were diluted in Dulbecco's modified Eagle's medium (DMEM) in series. To evaluate the cytotoxicity, the survival of 3T3/NIH mouse fibroblasts was measured photometrically using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after a 24 h-exposure period. Genotoxicity was indicated by micronuclei (MN) formation, and modification of the normal cell was analysed by light microscopy (400×). Statistical analysis was performed by one-way anova, followed by a multiple-comparison Tukey post hoc test (P < 0.05). Results, All groups exhibited a dose-dependent cytotoxicity. However, CP showed a similar cytotoxic effect when compared with DMEM-untreated control (UC) group. HP and SPC were significantly more cytotoxic than SP. The genotoxicity test showed that SPC and SP had an intermediate rate of MN frequency when compared with the UC group. The mean rate of MN frequency for HP was higher and statistically more significant than for the other groups tested. No difference was observed when CP and UC groups were compared. Conclusions, Sodium percarbonate showed cytotoxicity and genotoxicity similar to those of the other products tested. However, before SPC is used clinically, studies should be conducted to confirm its safety in vivo. [source] In vivo effects of amorphous calcium phosphate-containing orthodontic composite on enamel demineralization around orthodontic bracketsAUSTRALIAN DENTAL JOURNAL, Issue 3 2010T Uysal Abstract Background:, The aim of this study was to evaluate the in vivo effects of an amorphous calcium phosphate-containing orthodontic composite in reducing enamel demineralization around orthodontic brackets, and to compare it with the control. Methods:, Fourteen orthodontic patients were divided into two equal groups. They received brackets fitted to all first premolars, bonded with either Aegis Ortho® (The Bosworth Co.), an ACP-containing orthodontic composite (experimental group), or Concise® (3M Dental Products), a resin-based orthodontic composite (control group). After 30 days, the teeth were extracted and longitudinally sectioned, and evaluated by superficial-microhardness analysis. The determinations were made at the bracket edge cementing limits and at occlusal and cervical points 100 and 200 ,m away from the edge. In all of these positions, indentations were made at depths of 10, 20, 30, 50, 70, and 90 ,m from the enamel surface. Analysis of variance (ANOVA) and Tukey post hoc test was used. The statistical significance level was set at p <0.05. Results:, The ANOVA showed statistically significant differences for position, material, depth, and their interactions (p <0.001). The multiple comparison test showed that the ACP-containing orthodontic composite was significantly more efficient than the control composite, reducing enamel demineralization in almost all evaluations (p <0.001). Conclusions:, Present results indicated that ACP-containing orthodontic composite for bonding orthodontic brackets successfully inhibited demineralization in vivo. This effect was localized to the area around the brackets and was statistically significant after 30 days. [source] Pergolide mesylate can improve sexual dysfunction in patients with Parkinson's disease: the results of an open, prospective, 6-month follow-upEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2004M. Pohanka One of the most disabling problems in males suffering from advanced Parkinson's disease (PD) is complex sexual dysfunction. The effect of dopamine replacement or dopaminergic stimulation on sexual dysfunction has been recently examined and described in patients treated by L-DOPA or apomorphine. Pergolide mesylate is another dopamine agonist with a known high affinity to hD(2S) subtype and a lower affinity to hD(2L) subtype of D2 dopaminergic receptors. It has been repeatedly shown to be a highly effective treatment of the complicated and advanced stages of PD. The current study has been designed to assess its efficacy in the treatment of sexual dysfunction, which frequently accompanies the complicated stage of PD in males. Fourteen male patients suffering from PD, each of whom had been treated with L-DOPA, and in whom additional treatment with peroral dopaminergic agonist (DA) was needed, were followed for a 6-month period. Pergolide mesylate (Permax) was given to each patient, and titrated to a total daily dose of 3 mg. All of the patients were taking L-DOPA. The assessments performed before the start of pergolide treatment consisted of a neurological examination, including Unified Parkinson's Disease Rating Scale (UPDRS) III and IV subscales scoring, Mini Mental State Examination (MMSE) scoring, the neuropsychological examination including Zung scale scoring to exclude depression, biochemical and haematological examinations including the examination of prolactine serum levels; and a sexological examination during which the patients filled-in the International Index of Erectile Function (IIEF) questionnaire. These examinations were repeated during the control assessments at months 1, 3 and 6. To compare the examination results, anova, Friedmann's anova (non-parametric) and Tukey post hoc tests were used. There were statistically significant differences between the values of UPDRS III motor subscale, UPDRS IV (complications of therapy) subscale and all subscales of IIEF when months 0 and 1 were compared with the results obtained at months 3 and 6. The differences between months 0 and 1 and months 3 and 6 (in these items) were virtually insignificant. In conclusion, pergolide substantially improved sexual function in the younger male patients who were still interested in sexual activities. In such cases, the introduction of pergolide might be a better choice than treatment with sildenafile, which usually meets several contraindications in common PD male population. [source] Physical-mechanical properties of glass ionomer cements indicated for atraumatic restorative treatmentAUSTRALIAN DENTAL JOURNAL, Issue 3 2009CC Bonifácio Abstract Background:, This study evaluated mechanical properties of glass ionomer cements (GICs) used for atraumatic restorative treatment. Wear resistance, Knoop hardness (Kh), flexural (Fs) and compressive strength (Cs) were evaluated. The GICs used were Riva Self Cure (RVA), Fuji IX (FIX), Hi Dense (HD), Vitro Molar (VM), Maxxion R (MXR) and Ketac Molar Easymix (KME). Methods:, Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. Fs, Cs, and Kh were analysed with one-way ANOVA. Results:, The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, Fs and Cs, KME, FIX and HD had the best performance. Strong explanatory power between Fs and the Kh (r2 = 0.85), Cs and the Kh (r2 = 0.82), long-term wear and Fs of 24 h (r2 = 0.79) were observed. Conclusions:, The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear. [source] Intra-articular stabilisation of the equine cricoarytenoid jointEQUINE VETERINARY JOURNAL, Issue 6 2008J. CHEETHAM Summary Reasons for performing study: The success of laryngoplasty is limited by abduction loss in the early post operative period. Objective: To determine the efficacy of polymethylmethacrylate (PMMA) in stabilising the cricoarytenoid joint (CAJ) and reducing the force on the laryngoplasty suture. Hypothesis: Injection into the cricoarytenoid joint resists the forces produced by physiological laryngeal air flows and pressures thereby reducing the force experienced by the laryngoplasty suture. Methods: Ten cadaver larynges were collected at necropsy and PMMA was injected into one CAJ at selected random. Each larynx was subjected to physiological conditions with with constant (static) or cycling (dynamic) flow. The specimens were tested sequentially in each of 4 conditions: 1) bilateral full abduction (Control 1); 2) transection of the suture on the side without PMMA; 3) bilateral abduction achieved by replacing the suture (Control 2); and 4) cutting the suture on the PMMA side. Tracheal pressure and flow and pressure in the flow chamber were recorded using pressure and flow transducers. The strain experienced by each suture during bilateral abduction (Controls 1 and 2) was measured. Statistical comparison of the 4 conditions was performed using a mixed effect model with Tukey's post hoc test for multiple comparisons. The strain gauge data were analysed by paired comparison of the regression slopes. Results: In the static and dynamic states, tracheal pressure increased and tracheal flow decreased when the suture on the non-cement side was cut (P<0.05). There was no significant difference in any outcome measure between PMMA injected into the CAJ and bilaterally abducted specimens (Controls 1 and 2) for either condition. The rate of increase in strain with increasing translaryngeal pressure was significantly less on the suture with PMMA placed in the CAJ (P = 0.03). Conclusions: These data provide strong evidence that injecting PMMA into the CAJ resists the collapsing effect of physiological airflows and pressures in vitro and reduces the force experienced by the laryngoplasty suture during maximal abduction. Potential relevance: Augmentation of prosthetic laryngoplasty with this technique may reduce arytenoid abduction loss in the early post operative period. [source] Homocysteine, the MTHFR 677 C,T polymorphism and family history of premature cardiovascular diseaseJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2009A. Carey Background:, Cardiovascular disease (CVD) is the main cause of premature death in the UK and accounts for 36% of all premature male deaths and 27% of female deaths every year (British Heart Foundation, 2006). Although many risk factors for CVD are known, family history has been identified as being of particular importance in premature CVD (Lloyd-Jones et al., 2004). Recently, it was suggested that an elevated homocysteine (tHcy) may be associated with premature CVD (Homocystiene Studies Collaboration, 2002). The main genetic determinant of tHcy is the common 677 C,T polymorphism, in the enzyme methylenetetrahydrofolate reductase (MTHFR), which is prevalent in approximately 10% of the UK population. Relatively few studies have examined the association between tHcy and premature CVD and hardly any have considered the role of this polymorphism. The aim of this study therefore was to examine the relationships between the MTHFR 677 C,T polymorphism, tHcy and a family history of CVD in patients with established premature CVD. Methods:, An analysis was conducted on medical, lifestyle and family history data collected from patients and age-sex matched controls, recruited through the GENOVIT study in 2003. This case,control study involved n = 404 premature CVD patients and a similar number of age-sex matched controls, all of whom were screened for the TT genotype. A subset of patients (n = 196) and controls (n = 167) provided a blood sample, from which the tHcy concentration was established. Independent sample t -tests were used to determine differences between patients and controls and differences among genotype groups were examined using a one-way analysis of variance, followed by a Tukey's post hoc test. Results:, Plasma tHcy was significantly elevated in patients with a family history of CVD (compared to those without) (P = 0.013). A nonsignificant trend towards higher tHcy (compared to those without) was observed in patients with the TT genotype (P = 0.419). Furthermore, specifically in those with the TT genotype, those with a family history of CVD (compared to those without) showed significantly higher tHcy concentrations (P < 0.005). Those with the TT genotype who smoked had significantly higher tHcy (P < 0.05) than the CC and CT genotypes. Discussion:, The findings presented provide evidence to support an association between the MTHFR 677C,T polymorphism, elevated homocysteine and family history of premature CVD. Given that dietary levels of riboflavin have been shown to lower homocysteine specifically in individuals with the TT genotype (McNulty et al., 2006), these results have implications for the dietary management of premature CVD in those individuals with a genetic predisposition for elevated tHcy. In conclusion, further research in larger cohort numbers, regarding the correlation between family history, tHcy and the MTHFR polymorphism, would be beneficial for establishing their cause and effect relationship. References British Heart Foundation (2006) All Deaths and Deaths Under 75 by Cause and Sex, 2005, England, Wales, Scotland, N Ireland and United Kingdom. Available at http://www.bhf.org.uk/research_health_professionals/resources/heart_statistics.aspx. Homocystine Studies Collaboration (2002) Homocysteine and the risk of ishaemic heart disease and stroke. JAMA288, 2015,2022. Llyod-Jones, D.M., Nam, B.H., D'Agostino, R.B., Levy, D., Murabito, J.M., Wang, T.J., Wilson, P.W. & O'Donnell, C.J. (2004) Parental cardiovascular disease as a risk factor for cardiovascular disease in middle-aged adults, a prospective study of parents and offspring. JAMA291, 2204,2211. McNulty, H., Dowey le, R.C., Strain, J.J., Dunne, A., Ward, M., Molloy, A.M., McAnena. L.B., Hughes, J.P., Hannon-Fletcher, M. & Scott, J.M. Riboflavin lowers homocysteine in individuals homozygous for the MTHFR 677C->T polymorphism. Circulation113, 74,80. [source] Fracture Force, Deflection, and Toughness of Acrylic Denture Repairs Involving Glass Fiber ReinforcementJOURNAL OF PROSTHODONTICS, Issue 4 2008Ioannis Kostoulas DDS Abstract Purpose: Fractures in acrylic resin dentures occur quite often in the practice of prosthodontics. A durable repairing system for denture base fracture is desired to avoid recurrent fracture. The purpose of this study was to evaluate the fracture force, deflection, and toughness of a heat-polymerized denture base resin repaired with autopolymerized resin alone (C), visible light-polymerizing resin (VLC), or autopolymerizing resin reinforced with unidirectional (Stick) (MA-FS) and woven glass fibers (StickNet) (MA-SN). Another group was repaired with autopolymerized resin after wetting the repair site with methyl methacrylate (MA-MMA) for 180 seconds. A group of intact specimens was used as control. Materials and Methods: Heat-polymerizing acrylic resin was used to fabricate the specimens. The specimens (10 per group) were sectioned in half, reassembled with a 3-mm butt-joint gap, and repaired. A cavity was included when glass fibers were used. Three-point bending was used to test the repaired site, and data were analyzed with one-way ANOVA and the Tukey's post hoc test (,, 0.05). Results: Fracture force, deflection, and toughness for the repaired groups without reinforcement (MA: 46.7 ± 8.6 N, 2.6 ± 0.3 mm, 0.08 ± 0.001 J; MA-MMA: 41.0 ± 7.2 N, 2.7 ± 0.4 mm, 0.07 ± 0.002 J) were significantly lower (p < 0.05) than the control group (C: 78.6 ± 9.6 N, 5.9 ± 0.4 mm, 0.27 ± 0.003 J). Repair with visible light-polymerizing resin (VLC, 15.0 ± 4.0 N, 1.2 ± 0.4 mm, 0.02 ± 0.0001 J) resulted in significant reduction of mechanical properties (p < 0.05). Reinforcement with glass fibers restored (MA-SN: 75.8 ± 9.2 N) or increased (MA-FS: 124.4 ± 12.5 N) the original strength. Conclusion: The most effective repair method was the use of autopolymerized resin reinforced with unidirectional glass fibers. [source] Prosthetic treatment of maxillary lateral incisor agenesis with osseointegrated implants: a 24,39-month prospective clinical studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2006Fernando Zarone Abstract Objectives: The present study aimed at evaluating the marginal bone resorption and the peri-implant tissue conditions around Narrow-Neck ITI implants in the implant,prosthetic treatment of the agenesis of maxillary lateral incisors. Material and methods: Thirty patients affected by monolateral or bilateral agenesis of the maxillary lateral incisors were selected. Thirty-four ITI-SLA Narrow Neck implants were inserted and loaded about 4 months after the surgical procedure. The final restorations were realized using Aureo Galvan Crowns veneered with feldspathic ceramics. The follow-up period ranged from 24 to 39 months. Both marginal bone resorption and soft tissue quality were evaluated. The data were statistically analysed using analysis of variance (ANOVA) for repeated measures, one-way ANOVA and Tukey's post hoc test (P=0.05). Results: During the 24,39-month follow-up period, no implant showed either pain and sensitivity or mobility. After 39 months of functional loading, a cumulative survival rate of 97.06% and a cumulative success rate of 94.12% were calculated. Conclusions: In case of maxillary lateral incisor agenesis, the implant,prosthetic approach has proved to be a reliable and predictable treatment for both re-establishment of function and aesthetics. Satisfactory values of marginal bone resorption over time and optimal conditions of peri-implant tissue around Narrow-Neck ITI implants were found. [source] | ||||||||||