262,792 research outputs found
Evaluation of the adhesion of fiber posts cemented using different adhesive approaches
No full textThe aim of this study was to investigate the adhesion of fiber posts cemented with luting agents that utilize three currently available adhesive approaches: etch-and-rinse, self-etch, and self-adhesive. Forty-two intact single-rooted human premolars were used in the study. Teeth were divided into six groups. In each group, a different resin cement with its adhesive system (if needed) and a fiber post were used. The groups were classified, according to the adhesive approach, into the following three categories. (i) Etch-and-rinse groups: Calibra resin cement/XPBond adhesive + self-curing activator (SCA)/RadiX Fiber Post (Dentsply Caulk), FluoroCore 2 core build-up material/XPBond + SCA/RadiX Fiber Post (Dentsply Caulk), and MultiCore Flow luting and core build-up material/Excite DSC adhesive/FRC Postec Plus fiber post (Ivoclar Vivadent). (ii) Self-etch group: Panavia F 2.0/ED primer (Kuraray)/RadiX Fiber Post (Dentsply Caulk). (iii) Self-adhesive groups: experimental self-adhesive cement/RadiX Fiber Post (Dentsply Caulk), and RelyX Unicem/RelyX Fiber Post (3M ESPE). The adhesion between the post and the root canal walls was assessed using the 'thin-slice' push-out test. In the test arrangement used, the self-etching approach may offer less favourable adhesion to root canal dentin in comparison with etch-and-rinse and self-adhesive approache
Cinematic representations of nationalist-religious ideology in Serbian films during the 1990s
No full textThis thesis is a critical exploration of Serbian film during the 1990s and its potential to provide a
critique of the regime of Slobodan Milosevic. In this dissertation I focus upon how selected films
provide insight into the ideological discourse of the 1990s within the Serbian socio-political and
cultural context. I discuss a range of Serbian films produced during the 1990s, and I analyse in
detail several films, in particular Pretty Village, Pretty Flame (Lepa sela, lepo gore, Srdjan
Dragojevic, 1995) and Wounds (Rane, Srdjan Dragojevic, 1998), in which I focus on the depiction
of nationalist and religious elements in the films. I analyse cinematic representations of the
nationalist-religious ideology, its characteristics, impacts and promotion. On the basis of this
analysis I consider the extent to which these cinematic representations are subversive.
My dissertation has seven chapters. In chapter 1, which is an introduction to the thesis, I
state my research questions and methodology. In chapter 2 I discuss the research context and
I consider literature relevant to my research. Since I am basing my research upon different
fields, I divide this chapter into three parts: the first one is devoted to the field of film and
religion in which I position this study; the second part is on the literature that I used for the
exploration of the socio-political context of the 1990s; and the last part is devoted to
literature written on Balkan, Yugoslav and Serbian cinema. In chapter 3 I provide an
analysis of the Serbian socio-cultural and political context of the 1990s. Chapter 3 is divided
into eight parts, in which I primarily focus on the creation, characteristics and impacts of the
nationalist-religious ideology. This discussion includes an analysis of the interaction
between the Church and the state in the promotion of this ideological discourse. This
chapter is important for the further analysis of Serbian film, its contextualization, and
understanding the main issues which films communicated. In chapter 4 I analyse Serbian
films produced during the 1990s. In the first part of this chapter, and for the purpose of
contextualization of Serbian film, I first briefly discuss the cinematic tradition of former
Yugoslavia: the Black Wave movement. I move on to discuss the cinematic context of the
1990s and the films produced over this period of time. I particularly focus on several films
which dealt with the political-ideological context of the 1990s. I discuss the most significant
films which dealt with the war, violence, ideology and the collapse of Serbian society under
the Milosevic regime. The aim of this chapter is to provide a cinematic context for the
analysed films and a clearer understanding of Serbian film of the 1990s as politically
engaged cinema. Chapter 5 is devoted to the film Pretty Village, Pretty Flame while in
chapter 6 I analyse the film Wounds. I analyse these two films separately because of their
unique depictions of the nationalist-religious ideology. Both chapters are structured the
same way and are divided into two major parts. In the first part of each chapter I consider
the film's plot, its genre and its production, as well as discussing the film's critical reception.
In the second part of each chapter I analyse the film narrative and images. At the end of each
chapter I discuss the results of my analysis. Chapter 7 is the last chapter of my thesis and is
devoted to the conclusion. In this final chapter I discuss the findings based on the cinematic
and contextual analysis in the previous chapters. As part of my final remarks, I outline the
contributions this study has made and future research that can be developed on the basis of
this thesis
Repair potential of a laboratory-processed nano-hybrid resin composite
No full textThe purpose of this study was to compare the 24-h composite-to-composite microtensile bond strength of Gradia Forte (GF) repaired with the same or a different material after different surface treatments. Different groups were set up, in which composite blocks of GF were subjected to the following treatments: Group 1, sandblasting with 50-microm aluminum oxide and 37% phosphoric acid etching (PA); Group 2, bur roughening and etching with 37% PA; Group 3, etching with 37% PA only. In all groups, a bonding resin was used as an intermediate agent prior to layering of the repair material (Gradia Direct (GD), Gradia (G), or GF). Bond strengths were then determined and analysed statistically. Scanning electron microscopy (SEM) evaluation of substrates and bonded interfaces was also performed. Surface treatment (P < 0.001) and repair materials (P < 0.001) were factors that significantly affected repair strength, whereas their interaction (P = 0.31) had no significant effect. Group 3 showed significantly superior repair strength to Groups 1 and 2, whereas Group 2 showed significantly weaker repair strength to Groups 1 and 3. Irrespective of surface treatment, GD and G gave similar results, which were better than those obtained using GF. The lowest probability of failure was found for GD and G in Group 3, whereas the highest was found for GF in Groups 1 and 2. Premature failures occurred mainly with G and GF. No pre-testing failures were found in the sandblasting/GD subgroup. Surface-treated composites showed different textures under SEM, whereas composite-repair bonds showed comparable interfacial feature
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effect of diagnostic method and operator’s experience on the detection of occlusal caries in posterior permanent teeth: an in vivo pilot study.
No full textAdhesion between fiber posts and resin luting agents: a microtensile bond strength test and an SEM investigation following different treatments of the post surface
No full textPurpose: (1) To evaluate the interfacial strength between FRC Postec posts and three luting agents (Multilink, Variolink 11, and MultiCore Flow) following different surface treatments, and (2) to observe the effect of sandblasting (Rocatec Pre) on the surface morphology of methacrylate-based fiber posts.
Materials and Methods: The posts received one of the following surface treatments: (1) sandblasting, (2) sandblasting + silanization, (3) silanization or (4) no treatment. The three luting agents were bonded to the post and the post-cement bond strength was evaluated with the microtensile test. SEM observation of sandblasted and nontreated posts was performed. Post-cement interfaces were also evaluated. Data were statistically analyzed with two-Way ANOVA with post treatment and luting agent as factors. Tukey's test was applied for post-hoc comparisons.
Results: Post treatment and the interaction between type of luting agent and type of post treatment were significant factors for bond strength (p < 0.001). The type of luting agent did not significantly influence bond strength (p = 0.07). Sandblasting + silanization performed better than sandblasting or no treatment (p < 0.001). Silanization resulted in significantly higher bond strengths than no treatment (p = 0.045). No differences were detected between sandblasting + silanization and silanization. SEM observation revealed an increased surface roughness and exposure of fibers in sandblasted posts.
Conclusion: Silanization was confirmed to be a reliable method for improving the bond strength of resin luting agents to fiber posts. Bond strength of resin luting agents to fiber posts was not influenced by the type of luting agent. The sandblasting procedure modified the methacrylate-based post surface texture
Coupling of composite resin cements to quartz fiber posts: a comparison of industrial and chairside treatments of the post surface
No full textPurpose: To evaluate the influence of surface treatments on microtensile bond strength of luting resin cements to fiber posts.
Materials and Methods: Forty-two quartz fiber posts (Light Post, RTD) were divided into 7 groups (n = 6) according to the surface treatment. I and 11: experimental patented industrial treatment consisting of zirconium oxide coating and silanization (RTD); III: industrial treatment followed by adhesive application (XPBond, Dentsply Caulk); IV: adhesive (XPBond); V: adhesive (Prime&Bond NT, Dentsply Caulk); VI: silane (Calibra Silane, Dentsply Caulk); VII: no treatment. Adhesives were used in the self-curing mode. Two cements (Sealbond, RTD - group 1, and Calibra, Dentsply Caulk - groups 11 to VII) were applied on the posts to produce cylindrical specimens. Post/cement interfaces were evaluated under SEM. The surface of the industrially coated posts was examined using energy dispersive analysis by x-ray. Cylinders were cut to obtain microtensile sticks that were loaded in tension at a crosshead speed of 0.5 mm/min until failure. Statistical analysis was performed using Kruskal-Wallis analysis of variance followed by Dunn's multiple range test for post-hoc comparisons (p < 0.05). Weibull analysis was also performed.
Results: The post/cement bond strength was significantly higher on fiber posts treated industrially (I: 23.14 +/- 8.05 MPa; II: 21.56 +/- 7.07 MPa; III: 22.37 +/- 7.00 MPa) or treated with XPBond adhesive (IV: 21.03 +/- 5.34 MPa) when compared to Prime&Bond NT application (V: 14.05 +/- 5.06 MPa), silanization (VI: 6.31 +/- 4.60 MPa) or no treatment (VII: 4.62 +/- 4.31) of conventional fiber posts (p < 0.001).
Conclusion: The experimental industrial surface treatment and the adhesive application enhanced fiber post to resin cement interfacial strength. Industrial pretreatment may simplify the clinical luting procedure
Post space cleaning using a new nickel titanium endodontic drill combined with different cleaning regimens.
No full textThis study compared the effect of two drills and five cleaning regimens on post space debridement. One hundred extracted premolars were instrumented and obturated with warm vertical compaction of gutta percha. The teeth were divided into two groups according to the drill used to remove gutta percha/sealer and for post space preparation: a Largo drill (Largo; Dentsply, St Quentin en Yvelines, France) or a MTwo-PF drill (Sweden&Martina, Due Carrare, Padova, Italy). The following cleaning regimens were used: EDTA, ultrasonics, ultrasonics + EDTA, phosphoric acid, and distilled water. Scanning electron microscopic images of the post spaces were taken, and the presence of debris and of open dentin tubules were evaluated. The ultrasonics + EDTA, phosphoric acid, and EDTA groups were comparable in open tubules scores for both drills and in debris scores after the use of MTwo-PF (p > 0.05). The ultrasonics and control groups performed significantly worse (p < 0.05). The MTwo-PF drill resulted as effective as the Largo drill in obtaining a good post space cleaning, especially when followed by ultrasonics + EDTA irrigant regimen
Protecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
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