1,720,974 research outputs found
Studio prospettico su restauri di V classe in composito con l’uso di due diversi adesivi smalto dentinali
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Valutazione della resistenza alla frattura di frammenti incisali riattaccati con diversi materiali e metodiche
No full textInterfacial nanoleakage and internal cement thickness of three esthetic crown systems
No full textObjectives: To evaluate interfacial nanoleakage expression of the combination of different cementation procedures and different crown systems. Methods: Forty-five human premolars prepared to receive single crowns were randomly divided into three groups (n = 15) based on the materials to be used for crown fabrication and cementation: group 1: Zirc (Ivoclar-Vivadent) cemented with Multilink Automix; group 2: Ivoclar disilicate IPS Empress 2 luted with Excite DSC in combination with Variolink II; group 3: AAdva Zirconia (GC) cemented with G-Cem Automix. The specimens were then assessed for interfacial nanoleakage expression and the amount of silver deposits along the interface was quantified. The thickness of the cement was assessed at 5 different levels: cervical margins, midway between the cervical margin and the occlusal wall along the axial walls and at the occlusal wall. The nanoleakage scores and the cement thickness were analyzed with Kruskall-Wallis non-parametric Analysis of Variance and Dunn's Multiple-range post hoc test. Results: Group 2 showed significantly less nanoleakage expression than group 1 (p < 0.05). The groups can be ranked in the following order 3 < 1 < 2 with regard to the cement thickness. Conclusions: There was no correlation among combination of different cementation procedures and different crown systems and interfacial nanoleakage. Also the cement thickness and the degree of nanoleakage cannot be related. The amount of cement found at the cervical margins of all groups showed discrepancies within a clinical acceptable range. © 2012 Academy of Dental Materials
SEM and rugosimetry for the analyses of the efficacy of different types of resin composites
No full textBACKGROUND: the aim of this study was verify the possibility of using flowable composites in class V restorations and in class II cervical margin
METHODS AND MATERIALS: the study was subdivided in two parts, in vivo and in vitro. The first contain 6 patients with a spot of flowable and microfilled resin on the vestibular surfaces of first superior molars. The in vitro part consists of 12 molar extracted in which was obtained class V restorations filled with flowable and microfilled. At 0 and 6 months impressions were taken for each tooth with Impregum Penta Soft and replicas were obtained with epoxy resin. The replicas were analyzed with profilometer and S.E.M. microscope. The statistic results were analyzed by the Paired Samples T Test and the Indipendent Samples T Test.
RESULTS: each material, flowable and microfilled, looks modified at the microscopic and profilometric analysis even if the flowable surface modifications was more apparent.
CONCLUSIONS: flowable resins can be used in class II and V cervical margins if non exposed to mechanical stresses
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