Fábio Barbosa de Souza

Deproteinized dentin: a favorable substrate to self-bonding resin cements?

The adhesive performance on deproteinized dentin of different self-adhesive resin cements was evaluated through microtensile bond strength (μTBS) analysis and scanning electron microscopy (SEM). Occlusal dentin of human molars were distributed into different groups, according to the categories: adhesive cementation with two-step bonding systems-control Groups (Adper Single Bond 2 + RelyX ARC/3M ESPE; One Step Plus + Duolink/Bisco; Excite + Variolink I/Ivoclar Vivadent) and self-adhesive cementation-experimental groups (Rely X Unicem/3M ESPE; Biscem/Bisco; MultiLink Sprint/Ivoclar Vivadent). Each group was subdivided according to the dentin approach to: α, maintenance of collagen fibers and β, deproteinization. The mean values were obtained, and submitted to ANOVA and Tukey test. Statistical differences were obtained to the RelyX Unicem groups (α = 13.59 MPa; β = 30.19 MPa). All the BIS Group specimens failed before the mechanical tests. Dentinal deproteinization provided an improved bond performance for the self-adhesive cement Rely X Unicem, and had no negative effect on the other cementing systems studied.

Monitoring solution in a dynamic Service-Oriented Platform

Abstract Quality attributes play a relevant role in Service-Oriented Computing, as they allow distinguishing similar services. These attributes impact on various activities related to the life-cycle of service-based applications (SBAs). The effect starts from service discovery and permeates other activities such as service level agreement establishment and monitoring. Considering the relevance of quality attributes, they must be precisely defined. Moreover, as these attributes are intrinsically dynamic, they must be permanently monitored. This paper proposes a meta-model that formally defines and connects service, quality and event domains. The connection between service and quality domains enables the design of models that specify applications’ functional and non-functional requirements. The connection between quality and event domains allows engineers to define how quality metrics can be computed based on a set of runtime events. Conformant models can be interpreted at runtime by compatible platforms to dynamically configure their monitoring mechanisms.

Influência de pontas diamantadas CVD sobre o selamento marginal de um primer autocondicionante

Alterations produced on the dental surface after cavity prepa- ration may influence the effecti- veness of the restoring procedure. The purpose of this study was to verify the influence of CVD system burs on marginal sealing of a self- etching primer (Clearfil SE Bond - Kuraray). Twenty-four class II cavities were made in twelve hu- man molars, with 12 cavities per group: G1 - (CVD system); G2 (conventional diamond burs). Af- ter the placement of restorations (Clearfil SE Bond+Clerafil AP- X/Kuraray), the teeth were sto- red in saline solution (24 hours, 37 °C), thermocycled (500 cycles, 5°/55 °C, with a dwell time of 15 seconds), immersed in basic fuc- sin (24 hours, 37 °C), washed and sectioned through the gingival margin for verification. The mi- croleakage scores ranged from zero (no microleakage) to 3 (ma- ximum microleakage). The Mann Whitney test did not indicate a statistical difference between the subgroups G1 and G2, and betwe- en enamel and dentine of a same group (p>0,05). However, abso- lute results demonstrated that CVD system exercised negative influence on the marginal sealing of the restorations performed with the studied self-etching primer. Key words: dental cavity prepa- ration, dentin-bonding agents, dental leakage.

Durability of the adhesive cementation to the dentin substract

Objective The aim of this study was to evaluate, in vitro, the union stability of resin cements to the dental substract through microtensile bond strength (µTBS) analysis and scanning electron microscopy (SEM). Methods Fifty-four third human molars, stored in water for a short (24 hours) and long period of time (1 year) presented a flat oclusal superficial dentin. The teeth were distributed in six different groups: G1- Panavia F2.0/Kuraray; G2- RelyXUnicem/3M ESPE; G3- G-Cem/GC; G4- Biscem/ Bisco; G5- Panavia F2.0/Kuraray without pre-treatment and G6- Multilink Sprint/Ivoclar-Vivadent which were adhered to its respective indirect resin composite restoration, (G1- Clearfil AP-X/Kuraray; G2- Filtek Z350/3M ESPE; G3- Gradia Direct X(tm)/GC; G4- Aelite(tm)/ Bisco; G5- Clearfil AP-X/Kuraray; G6- Tetric Ceram/ Ivoclar-Vivadent). The resin blocks were cemented and the sticks were obtained by tooth, with an area of adhesive interface of 0,8mm² (±0,2). Results The mean values, submitted to Mann-Whitney and Kruskal-Wallis tests (α = 5%) were in MPa after 24 hours: G1 = 9.66 (A), G2 = 13.37 (A); G3 = 15.89 (A); G5 = 4.18 (B); G6 = 11.01 (A) and after 1 year: G1 = 9.75 (A), G2 = 11.73 (A); G3 = 20.10 (B); G5 = 6.80 (A); G6 = 21.09 (B). All G4 group presented pretest failures. Conclusion During the one year period, with the exception of BisCem, the self-adhesive resin cements were a favorable alternative for the adhesive cementation, standing out among these, the G-Cem and Multilink Sprint.