407 resultados para Adhesive
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The tissue microarray (TMA) technique allows multiple tissue samples in a single block. Commercial adhesive tape is used to avoid the loss of tissue samples during the immunostaining process. Few reports exist in the literature comparing the use of these adhesive tapes to other adhesive techniques. The objective of this study was to compare loss of sections adhered to slides using commercial adhesive tapes versus using silanized only slides. TMA was constructed with varying tissues using a fixed-base device (Beecher Instruments), placing 108 cylinders of 1 mm diameter in duplicate, spaced 1.2 mm apart. Section of 4 mu m were cut from the TMA block and adhered to 30 silanized slides and 30 commercial glass slides using adhesive tape, according to manufacturer's recommendations. Vimentin immunoexpression was evaluated by immunohistochemistry. Antigenic recovery was realized in citrate buffer using a microwave oven. Cylinder loss in the immunohistochemical process was quantified and expressed as: total (>80%), almost complete (75-79%), or partial (50-74%). The commercial adhesive tape group presented lesser total loss (1.1 versus 6.4%), almost complete loss (2.2 versus 3.5%), and partial loss (2.1 versus 3.8%) than the silanized slide group (ANOVA, P < 0.05). The sum of total and almost complete losses in the silanized slide group was 9.9%, greater than the losses in slides using commercial adhesive tapes (3.3%) and less than reported and considered acceptable in the literature (10-30%). In conclusion, the use of silanized only slides presents very satisfactory results, requires less training, and reduces costs significantly, thus justifying their use in research.
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This paper reports a case of tooth replantation in which the splinting was performed with stainless steel orthodontic wire and a widely marketed brand of quick-setting cyanoacrylate ester adhesive (Super Bonder((R))). The long-term clinical and radiographic success of the case reported in this paper indicates that the splinting technique using a quick-setting cyanoacrylate ester adhesive may be a feasible option for making a rapid, simple and efficient contention of replanted teeth in situations where the routinely used materials are not readily available.
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Dental trauma is more common in young patients and its sequelae may impair the establishment and accomplishment of an adequate treatment plan. This paper reports a case of complicated crown-root fracture in a young adult that was treated using adhesive tooth fragment reattachment and orthodontic root extrusion. Considering the time elapsed to follow up, the fracture extension, the amount of remaining root portion and the patient's low socioeconomic status, the treatment approach proposed for this case provided good functional and aesthetic outcomes. Clinical and radiographic results after 2 years were successful. This case report demonstrates the importance of establishing a multidisciplinary approach for a successful dental trauma management.
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The purpose of this study was to evaluate stress distribution in the hybrid layer produced by two adhesive systems using three-dimensional finite element analysis (FEA). Four FEA models (M) were developed: Mc, a representation of a dentin specimen (41 x 41 x 82 mu m) restored with composite resin, exhibiting the adhesive layer, hybrid layer (HL), resin tags, peritubular dentin, and intertubular dentin to simulate the etch-and-rinse adhesive system; Mr, similar to Mc, with lateral branches of the adhesive; Ma, similar to Mc, however without resin tags and obliterated tubule orifice, to simulate the environment for the self-etching adhesive system; Mat, similar to Ma, with tags. A numerical simulation was performed to obtain the maximum principal stress (sigma(max)). The highest sigma(max) in the HL was observed for the etch-and-rinse adhesive system. The lateral branches increased the sigma(max) in the HL. The resin tags had a little influence on stress distribution with the self-etching system. (C) 2012 Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Objectives: the purpose of this study is to employ optical microscopy to measure the thickness of the hybrid layer and the penetration (tags) of an aggressive self-etching adhesive system into sound dentin.Methods: occtusat cavities were prepared in 40 extracted human posterior teeth. The prepared teeth were randomly assigned to four experimental groups with 10 specimens each. The self-etching adhesive system Adper Prompt L-Pop was applied to the dentin surface as follows: Group 1: cavosurface enamel was etched for 60 s and dentin for 20 s with 35% phosphoric acid get, immediately followed by application of the self -etching adhesive with a brush to the entire cavity for 15 s; Groups 2, 3, and 4: no pre-etching was performed, and the self -etching adhesive was applied to both enamel and dentin for 15, 30 and 45 s, respectively. After curing, the cavities were fitted with composite resin Fittek Z250. Afterwards, the teeth were decalcified and the restorations were carefully removed for later embedding in paraffin. The specimens were serially sectioned at 6 mu m of thickness and sequentially mounted in glass slides. These sections were stained with Brown and Brenn staining for posterior analysis and measurement of the hybrid layer and resin tags on a tight microscope with a micrometric ocular 40/075. The results were submitted to analysis of variance at the 5% level.Results: whenever there was significance, the Tukey test was applied at the 5% level. The specimens receiving application of acid etching before the selfetching. adhesive displayed a larger thickness of the hybrid layer; on the other hand, specimens receiving only application of the self -etching adhesive on dentin for 15, 30 and 45 s exhibited similar thickness of the hybrid layer. As regards the resin tags, no statistically significant differences could be found between the study groups.Conclusions: it could be concluded that the increase in the time of application of the self-etching adhesive Adper Prompt L-Pop did not significantly influence the formation and thickness of hybrid layer, as well as its penetration into the sound dentin surface. (c) 2005 Elsevier Ltd. All rights reserved.
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This study evaluated the microtensile bond strength test (mu T), micromorphology of resin-enamel interface (RET) and etching patterns (EP) promoted by the etch-and-rinse adhesive, Prime&Bond NT (PB), and two self-etching adhesives, Clearfil SE Bond (SE) and Adper Prompt L-Pop (APR), to ground bovine enamel surfaces' when applied at temperatures of 5 degrees C (C), 40 degrees C (H) and 20 degrees C (R). Materials and Methods. Sixty-three bovine incisors were randomly divided into nine experimental groups (n=7) according to adhesive systems and temperatures. The buccal enamel surfaces were flattened with 600-grit SiC paper and abraded with a diamond bur under water-cooling. The adhesive systems were applied according to the manufacturer's instructions. After the restorative procedures, the specimens were sectioned into five slabs. Four slabs were prepared for mu T and one for interface analysis. For etching pattern analysis, the remaining 16 bovine enamel fragments were used (n=2). The adhesives were applied and the surfaces were rinsed with organic solvents after application. The specimens for RET and EP analysis were prepared for SEM analysis. Results. No significant differences among the adhesives were found at R temperature. However, at 5 degrees C, PB and APR presented lower bond strength than SE. At H temperature, higher bond strength was observed for PB than for APR and SE. At C and H temperature, formation of the interdiffusion zone was impaired and the treated enamel surfaces presented an undefined EP.
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Objectives: To evaluate the pulpo-dentin complex response to a dentin adhesive application in deep cavities performed in human teeth.Methods: Deep class V cavities were prepared on the buccal surface of 46 premolars. The remaining dentin of the axial wall received 10% phosphoric acid and dentin adhesive (group DA), or was protected before the acid and dentin adhesive application with calcium hydroxide cement (group CH). Half of the teeth, which received the acid application directly over the axial wall, were contaminated prior to the procedures with dental plaque collected from the patient's own teeth (group DAC). The plaque was placed on the dentin for 5 min and then the cavity was washed. All teeth were restored with a light-cured composite resin. The teeth were extracted after 7, 30 or 60 days and prepared according to normal histologic techniques. Serial sections were stained with WE, Masson's trichrome and Brown & Brenn technique for demonstration of bacteria.Results: the histopathologic evaluation showed that in groups DA and DAC, the inflammatory response was more evident than in group CH. Also, the intensity of the pulp reaction increased as the remaining dentin thickness decreased. There was no statistical difference in the inflammatory response between the groups DA and DAC.Conclusion: Based on the experimental conditions, we concluded that the All Bond 2 adhesive system, when applied on dentin in deep cavities, showed an acceptable biocompatibility. However, the intensity of the pulpo-dentin complex response depends on the remaining dentin thickness. (C) 1999 Elsevier B.V. Ltd. All rights reserved.
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The aim of the study was to evaluate the biocompatibility of an adhesive system and a resin component when implanted into connective tissue of rats. Forty sponges embedded in both materials: Scotchbond MP (SBMP/3M - Group A) and 2 - hydroxyethyl-methacrylate (HEMA - Group B), were implanted into dorsal connective tissue of 20 animals. After 7, 15, 30, or 60 days of the implantation, the animals were sacrificed; implant sites were excised and immersed for 24 hours in Kamovisky's fixative. The samples were processed under routine histologic technique, being stained with H & E. Histological evaluation showed that both materials promoted at 7 days intense inflammatory response with predominance of neutrophils and macrophages. The intense connective reaction was replaced for fibroblastic proliferation associated with macrophages and foreign body giant cells over time. The persistent moderate inflammatory reaction adjacent to scattered fragments of materials was greater to HEMA than to the SBMP. Both experimental materials did not show acceptable biocompatibility with connective tissue of rats in spite of allowing an evident connective tissue healing.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)