Publications by authors named "Andreia B de Paula"

Objective: Water sorption, high volumetric shrinkage, polymerization stress, and potential estrogenic effects triggered by leached compounds are some of the major concerns related to BisGMA-TEGDMA co-monomer systems used in dental composites. These deficiencies call for the development of alternative organic matrices in order to maximize the clinical lifespan of resin composite dental restorations. This study proposes BisGMA-free systems based on the combination of UDMA and a newly synthesized diurethane dimethacrylate, and evaluates key mechanical and physical properties of the resulting materials.

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Thiourethane (TU) additives and difunctional, polymerizable crosslinking agents have been demonstrated to increase toughness in methacrylate-based materials. The aim of this study was to evaluate the potential reinforcement of acrylic denture bases by combining thiourethane additives and 1,6 hexanediol dimethacrylate (HDDMA) as an additional crosslinking agent. One commercial acrylic resin (Nature-Cryl MC; GC America) was tested by adding 0 (control) or 10 wt% TU, each of them combined with 0 (control), 10, 20 and 30 wt% HDDMA, for a total of 8 experimental groups.

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Objectives: To evaluate the antibacterial activity, bacterial viability, cytotoxicity, and mechanical/physical properties of a novel methacrylate triclosan-derivative monomer (TM) incorporated in dental resin composite.

Methods: TM was synthesized by esterification and, after characterization by FT-IR, was added to an experimental composite. Samples were divided into two groups according to TM presence, i.

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The use of antimicrobial monomers, linked to the polymer chain of resin composites, is an interesting approach to circumvent the effects of bacteria on the dental and material surfaces. In addition, it can likely reduce the incidence of recurrent caries lesions. The aim of this study was to evaluate the effects of a novel Triclosan Methacrylate (TM) monomer, which was developed and incorporated into an experimental resin composite, on Streptococcus mutans (S.

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The aim of this study was to evaluate the in vitro antibacterial and biofilm inhibition properties of glass ionomer restorative cements. Ketac Nano, Vitremer, Ketac Molar Easymix and Fuji IX were analyzed using the following tests: a) agar plate diffusion test to evaluate the inhibitory activity of cements against S. mutans (n=8); b) S.

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This study evaluated the effects of chemical agents on the physical properties and structure of primary pulp chamber dentin using surface roughness, microhardness tests, and scanning electron microscopy (SEM). Twenty-five primary teeth were sectioned exposing the pulp chamber and were divided into five groups (n = 5): NT, no treatment; SH1, 1% sodium hypochlorite (NaOCl); SH1U, 1% NaOCl + Endo-PTC®; SH1E, 1% NaOCl + 17% EDTA; and E, 17% EDTA. After dentin treatment, the specimens were submitted to roughness, microhardness testing, and SEM analysis.

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Purpose: To evaluate in the laboratory the roughness (Ra) and micromorphology surface of the nanofilled resin-modified glass-ionomer (Ketac N100) subjected to biomechanical degradation, compared to Vitremer, Ketac Molar Easymix and Fuji IX.

Methods: Specimens obtained from the ionomers were divided into two storage groups (n = 10): relative humidity and S. mutans biofilm (biodegradation).

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This study evaluated the influence of material combinations used in the resin coating technique (RCT) on the marginal adaptation of indirect restorations with gingival margins in enamel (EM) and cement (CM). Eighty third-molars were used. Two cavities were prepared in each tooth.

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Objectives: To evaluate: (1) the in vitro antibacterial, cytotoxic and mechanical properties of a resin-modified glass ionomer cement (RMGIC) containing different concentrations of chlorhexidine (CHX) and (2) the in vivo microbiologic action of the best concentration of CHX associated with the RMGIC applied on remaining dentine after indirect pulp treatment (IPT).

Methods: For the in vitro studies, RMGIC was associated with 0.2, 0.

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Objectives: To characterize the mechanical and biological properties of a resin-modified glass ionomer cement (RMGIC) containing doxycycline hyclate.

Methods: The antibacterial effect of RMGIC containing 1.5, 3.

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This study evaluated the Knoop hardness and polymerization depth of a dual-cured resin cement, light-activated at different distances through different thicknesses of composite resin. One bovine incisor was embedded in resin and its buccal surface was flattened. Dentin was covered with PVC film where a mold (0.

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This study evaluated the effect of different light energy densities on conversion degree (CD) and Knoop hardness number (KHN) of RelyX ARC (RLX) resin cement. After manipulation according to the manufacturer's instructions, RLX was inserted into a rubber mold (0.8 mm x 5 mm) and covered with a Mylar strip.

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The aim of this study was to compare the in situ and in vitro performances of a laser fluorescence (LF) device (DIAGNOdent 2095) with visual inspection for the detection of occlusal caries in permanent teeth. Sixty-four sites were selected, and visual inspection and LF assessments were carried out, in vitro, three times by two independent examiners, with a 1-week interval between evaluations. Afterwards, the occlusal surfaces were mounted on the palatal portion of removable acrylic orthodontic appliances and placed in six volunteers.

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This study evaluated the compressive strength and marginal adaptation of composite onlays using indirect and direct techniques after thermal and mechanical cycling. Onlay standardized cavities were prepared in 50 permanent molars and restored with Z-250 resin composite using indirect (IRT) or direct (DRT) restorative techniques. The restorations were either submitted or not submitted to thermal (500 cycles, 5 degrees to 55 degrees C) and mechanical cycling (50,000 cycles, 50N).

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This article is the first known case report of Fraser syndrome in the dental literature. Its purpose was to present the clinical manifestations, oral findings, and dental treatment of a 14-year, 10-month-old female patient. Fraser syndrome is a rare recessive autosomal genetic disorder characterized by multisystemic malformation, usually comprising cryptophthalmos, syndactyly, and renal defects.

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The aim of this in vivo study was to evaluate the performance of laser fluorescence (LF) comparing different cut-off limits for occlusal caries detection. One hundred and thirty first permanent molars were selected. Visual examination and LF assessments were performed independently.

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