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The aim of this study was to compare the bond strength to three different depths of remaining human and bovine dentin, through shear bond strength test, and to establish a possible relationship among the depths of the substrates to contribute for the replacement of human dentin in bond strength tests. Forty-eight human teeth (H) and forty-eight bovine teeth (B), freshly extracted, stored in distilled water and frozen at -18 ° C for at most four weeks were used in this study. 240-, 400-, 600- and 800-grit sandpapers were used to expose the dentin and standardize the smear layer at 0.5, 1.0 and 2.0mm of dentin thickness. Scotchbond Multi-Purpose Plus adhesive system was used following the manufacturer’s instructions, on a standardized area of 4mm, followed by the incrementally application of Z100 resin composite (3M). The shear bond test was performed in the Instron Universal machine at cross-head speed of 0.5mm/min. Statistical analysis was performed by ANOVA (p

The aim of this study was to investigate the stress distribution generated in a veneer restoration of an upper central incisor compared to intact teeth using the finite element analysis after applying a lingual buccal loading at the incisal edge.Two models were developed: one model contained enamel, dentine, cementum, periodontal ligament, cortical and trabecullar bones, and the other model was a veneer restoration; both models were developed using MSC/Nastran software (MacNeal-Schwendler Corporation, Los Angeles, CA, USA) as the pre- and post-processor. A 10-N load was applied at the incisal edge from the lingual to the buccal side to simulate oral conditions in this area (protrusion).Von Mises stresses were then analysed for three different regions: A-B (enamel elements under the veneer or second enamel layer), A'-B' (buccal enamel and/or veneer element layer) and C-D (lingual enamel elements layer). A higher stress mode was observed for both models at the lingual cervical region.The presence of a veneer restoration on the incisors is a good alternative to mimic the behaviour of enamel under protrusion loading conditions. The use of veneers to replace enamel during rehabilitations is recommended.

SUMMARY The objective of this study was to determine whether the hardness of etch-and-rinse adhesives may be affected by the pretreatment of acid-etched dentin with potassium oxalate desensitizer. Unerupted human third molars were cut into crown segments by removing the occlusal enamel and roots. The pulp chamber of these crown segments was connected to a syringe barrel filled with phosphate-buffered saline so that the moisture of dentin was maintained during the bonding procedures. Three etch-and-rinse adhesives—two two-step systems (Adper Single Bond 2 [SB], One-Step [OS]) and one three-step system (Adper Scotchbond Multi-Purpose [MP])—were applied to acid-etched dentin that had been treated (experimental groups) or not (control groups) with potassium oxalate (BisBlock). The Knoop hardness (KHN) of adhesives was taken at different sites of the outer surface of the adhesive-bonded dentin. The KHN of the three tested adhesives applied to acid-etched dentin treated with potassium oxalate was significantly lower than that exhibited by the respective controls (not treated with oxalate; p

Objectives: To evaluate the influence of various photoactivation techniques on the internal gap, Knoop-hardness, and polymerization depth of silorane-and methacrylate-based composites in Class II restorationsMethods: Preparations were made in third molars (n = 10), according to composites (Filtek P60: methacrylate; Filtek P90: silorane) and photoactivation techniques (OC: occlusal photoactivation (control); OBL: occlusal+buccal+lingual photoactivation; and BLO: buccal+lingual+occlusal photoactivation (transdental)). Composites were inserted in two increments, both individually photoactivated for 20s. After 24h, specimens were sectioned and the ratio of internal gaps to interface length (%) recorded. Hardness was tested across the transversal section of restorations (1-4 mm below the surface)Results: Silorane restorations showed significantly lower gaps compared with methacrylate, regardless of polymerization technique (PConclusions: Internal gaps and hardness are affected by composite type and photoactivation. Despite the reduced values, hardness of silorane is not influenced by photoactivation or by depth. Internal gaps are dependent on the energy dose for both composites, with silorane showing lower internal gaps. (Eur J Dent 2012;6:133-140)

Objectives: To morphologically evaluate the permeability of different commercial dental adhesives using scanning electron microscopy.Methods: Seven adhesive systems were evaluated: one three-step system (Scotchbond Multi- Purpose - MP); one two-step self-etching primer system (Clearfil SE Bond – SE); three two-step etch-and-rinse systems (Single Bond 2 – SB; Excite – EX; One-Step – OS); and two single-step selfetching adhesives (Adper Prompt – AP; One-Up Bond F – OU). The mixture of primer and bond agents of the Clearfil SE Bond system (SE-PB) was also tested. The adhesives were poured into a brass mold (5.8 mm x 0.8 mm) and light-cured for 80 s at 650 mW/cm2. After a 24 h desiccation process, the specimens were immersed in a 50% ammoniac silver nitrate solution for tracer permeation. Afterwards, they were sectioned in ultra-fine slices, carbon-coated, and analyzed under backscattered electrons in a scanning electron microscopy.Results: MP and SE showed slight and superficial tracer permeation. In EX, SB, and OS, permeation extended beyond the inner superficies of the specimens. SE-PB did not mix well, and most of the tracer was precipitated into the primer agent. In AP and OU, “water-trees” were observed all over the specimens.Conclusions: Different materials showed distinct permeability in aqueous solution. The extent of tracer permeation varied according to the composition of each material and it was more evident in the more hydrophilic and solvated ones. (Eur J Dent 2010;4:429-439)

The purpose of this study was to evaluate the effect of chlorhexidine on the proteolytic activity of carious coronal and root dentin collected from patients. Sound dentin from freshly extracted human teeth was used as a control. Dentin fragments were mixed with a synthetic substrate for proteolytic enzymes (N-benzoyl-DL-arginine-naphthylamide – BANA) and the suspensions mixed with either 0.12% chlorhexidine digluconate or distilled water. These mixtures were incubated for 18 h at 37°C, color was developed by the addition of 0.1% Fast Garnet and their optical density was recorded spectrophotometrically. BANA hydrolysis measured by the optical density of incubated specimens was detected in all tested groups, but was significantly higher for carious than for sound dentin (p < 0.05). The proteolytic activity was reduced for carious coronal and root dentin by chlorhexidine (p < 0.05; 50 and 30%, respectively). Chlorhexidine also reduced the proteolytic activity in sound root dentin (p < 0.05; 20%). Conversely, changes in the proteolytic activity of sound coronal dentin were not observed in the presence of chlorhexidine. The reduction in proteolytic activity by chlorhexidine was significantly higher in carious coronal dentin than in carious root dentin (p < 0.05). In conclusion, part of the effect of chlorhexidine in controlling caries progression in humans may be due to a decrease in the proteolytic activity of carious coronal and root dentin. Because of the prolonged incubation time in the present study, similar results may be obtained clinically with prolonged dentin exposure to chlorhexidine, e.g. chlorhexidine-containing varnishes.

Objective: The aim of this study was to determine in arandomized, double-blind, placebo-controlled clinicaltrial the effects of typified propolis and chlorhexidinerinses on salivary levels of mutans streptococci (MS)and lactobacilli (LACT). Methods: One hundredpatients were screened for salivary levels of MS>100,000 CFUs/mL of saliva. All patients presentedwith at least one cavitated decayed surface. Sixtypatients met entry criteria. Subjects were adults 18-55 years old. After restoration of cavitated lesionspatients were randomized to 3 experimental groups:1) PROP-alcohol-free 2% typified propolis rinse (n =20); 2) CHX- 0.12% chlorhexidine rinse; 3) PL-placebomouthrinse. Patients rinsed unsupervised 15 mL ofrespective rinses twice a day for 1 min for 28 days.Patients were assessed for the salivary levels of MS(Dentocult SM) and LACT (Dentocult LB) at baseline,7-day, 14-day, and at 28-day visits (experimentaleffects) and at 45-day visit (residual effects). Generallinear models were employed to analyze the data.Results: PROP was superior to CHX at 14-day and28-day visits in suppressing the salivary levels of MS(p

In this work, mesoporous titania is prepared by templating latex sphere arrays with four different sphere diameters at the micrometric scale ( ϕ > 1 μm). The mesoporous titania homogeneously covers the latex spheres and substrate, forming a thin coating characterized by N 2 adsorption isotherm, small angle X-rays scattering, atomic force, field emission and transmission electronic microscopies. Mesoporous titania has been templated into different shapes such as hollow particles and monoliths according to the amount of sol used to fill the voids of the close packed latex spheres. Titania topography strongly depends on the adsorption of polymeric segments over latex spheres surface, which could be decreased by changing the dimensions of latex spheres ( ϕ = 9.5 μm) generating a lamellar architecture. Thus, micrometric latex sphere arrays can be used to achieve new surface patterns for mesoporous materials via a fast and inexpensive chemical route for construction of functional devices in different technological fields such as energy conversion, inclusion chemistry and biomaterials.

Objectives: To morphologically evaluate the permeability of different commercial dental adhesives using scanning electron microscopy. Methods: Seven adhesive systems were evaluated: one three-step system (Scotchbond Multi-Purpose - MP); one two-step self-etching primer system (Clearfil SE Bond – SE); three two-step etch-and-rinse systems (Single Bond 2 – SB; Excite – EX; One-Step – OS); and two single-step self-etching adhesives (Adper Prompt – AP; One-Up Bond F – OU). The mixture of primer and bond agents of the Clearfil SE Bond system (SE-PB) was also tested. The adhesives were poured into a brass mold (5.8 mm x 0.8 mm) and light-cured for 80 s at 650 mW/cm2. After a 24 h desiccation process, the specimens were immersed in a 50% ammoniac silver nitrate solution for tracer permeation. Afterwards, they were sectioned in ultra-fine slices, carbon-coated, and analyzed under backscattered electrons in a scanning electron microscopy. Results: MP and SE showed slight and superficial tracer permeation. In EX, SB, and OS, permeation extended beyond the inner superficies of the specimens. SE-PB did not mix well, and most of the tracer was precipitated into the primer agent. In AP and OU, “water-trees” were observed all over the specimens. Conclusions: Different materials showed distinct permeability in aqueous solution. The extent of tracer permeation varied according to the composition of each material and it was more evident in the more hydrophilic and solvated ones.

Diversos estudos demonstraram a origem infecciosa das principais moléstias que acometem a cavidade oral. Baseado nisso, tem sido bastante estudada a utilização de agentes antimicrobianos como auxiliares na prevenção e tratamento destas doenças. Todavia, os cirurgiões-dentistas, relutam em empregar tais agentes, às vezes, por desconhecimento dos grandes benefícios que tais terapias podem trazer. Tendo em vista estes fatores, o objetivo deste artigo é apresentar uma revisão sobre os principais agentes antimicrobianos que vêm sendo estudados para uso em Odontologia, enfocando sua atuação e sua aplicabilidade clínica.

A ciência vem evoluindo muito nas últimas décadas, principalmente em relação à conscientização da importância do diagnóstico precoce das doenças. Na Odontologia, o diagnóstico precoce das lesões de cárie tornou-se procedimento fundamental para a formulação do plano de tratamento que vise a prevenção, o conservadorismo e a promoção da saúde como um todo. Atualmente, vários métodos de diagnóstico têm sido utilizados: exame clínico, radiográfico, afastamento mecânico dos dentes, transiluminação por fibra óptica, detector elétrico de cáries, corantes e digitalização de radiografias. O objetivo neste trabalho foi revisar a literatura sobre os métodos clínicos e radiográficos de diagnóstico da doença cárie.

No cuidado cotidiano a crianças portadoras de cardiopatias congênitas percebe-se que os pais têm dificuldade para lidar, no domicílio, com as situações decorrentes da própria situação clínica, tais como cianose, prevenção da endocardite infecciosa, administração dos fármacos, etc. Com a finalidade de conhecer melhor os determinantes e possíveis soluções para tais situações, buscou-se identificar trabalhos científicos que abordassem as necessidades de informação e suporte a pais de criança cardiopatas, de 0 a 12 anos de idade, quanto à sete pontos: cardiopatia congênita propriamente dita; como lidar com a cianose; promoção de atividade física; promoção da alimentação; promoção da saúde bucal; prevenção da endocardite infecciosa e administração de fármacos. A busca foi realizada nas bases de dados MEDLINE, Cochrane, CINAHL, LILACS e Scielo, tendo-se limitado o período entre janeiro de 1997 e abril de 2007. Foram identificados 17 estudos, nos quais foi utilizada a análise temática de conteúdo como referencial metodológico. As categorias de análise foram os sete pontos previamente determinados. Os resultados mostraram que há categorias pouco exploradas, como, cuidados por ocasião de crise de cianose, promoção de atividade física e administração de fármacos. As outras concentram a maior parte dos estudos. São elas: conhecimento dos pais sobre a cardiopatia, promoção de alimentação (compreendendo aleitamento natural), promoção da saúde bucal e prevenção da endocardite infecciosa. Na análise geral percebe-se que o conhecimento dos pais, como um todo, é incompleto e fragmentado, tanto em países desenvolvidos, quanto nos em desenvolvimento. São descritos cuidados prestados por enfermeiros, dentistas e médicos, entre outros. Programas de capacitação de pais são poucos e apenas um é descrito como tendo êxito. Tais resultados apontam para a necessidade de mudanças, tanto em termos da relação direta com os pais, quanto em termos de re-organização dos serviços com vistas a abarcar de modo mais completo a necessidade de informação e suporte a estes In the daily care regarding to children bearing congenital heart disease one can realize that parents have difficulties to deal, at home, with situations coming from the clinical situation itself, such as cyanosis, prevention of the infective endocarditis, administration of medicines, etc. In order to know better the main causes and possible solutions to such situations, one has sought to identify scientifical studies which approach the necessities of information and support to the parents of congenital heart disease from 0 up to 12 years old concerning seven points: congenital heart disease in the very sense of the problem; how to deal with cyanosis; promotion of physical activity; promotion of feeding; promotion of mouth and teeth hygiene; prevention of infective endocarditis and administration of medicines. The search was done in the bases of data MEDLINE, Cochrane, CINAHL, LILACS and Scielo, in the period between 1997 January to 2007 April. Seventeen studies were identified and the tematic analyses of content was used as methodological reference. The categories to analyse were the 7 points previously determinate. The results showed that there are categories with few reaserches carried out, as, for example, the care in situations of cyanosis crisis, promotion of physical activity and administration of medicines. The other ones concentrate the most of the studies. They are: parents\' knowledge about heart disease, promotion of feeding (including breast-feeding), promotion of mouth and teeth hygiene and prevention of infective endocarditis. The general analyses demonstrates that the parents\' knowledge, as a whole, is incomplete and fragmented both in developed world\'s countries and in the developing world ones. Cares rendered by nursery, odontological and medical staff are described along other sort of cares. Programs to capacitate parents are few and only one is describeb as succesful. Such results point to the need of changing.concerning the straight relation with parents and concerning the re-organization of the service as well, in order to embrace in a more complete way the necessity of information and support to parents