Adaptação marginal do agregado de trióxido mineral com e sem cloreto de cálcio em retrocavidades

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência do cimento obturador e agente de irrigação final na infiltração marginal em situações de sobreobturações endodônticas

Objective: The objective of this paper was to verify if the final irrigation at 17% EDTA, separately or followed by chlorhexidine digluconate at 2% interferes on the apical marginal leakage in root canal overfilling, due to the use of two root canal filling materials (Sealer 26TM or SealapexTM). Methods: Forty lower incisors extracted, with a single root canal, were biomechanically prepared, at 2.0mm beyond the radicular apex, with ProTaper SystemTM, finishing it with the F3 instrument. Irrigation was accomplished with 1.0 mL NaOCl at 2.5% at each change of equipment caliper and, in the end, with 5.0 mL normal saline solution. After achieving this procedure, the foraminal channels was standardized with a file K 25 until its DO appears in the foraminal opening. From this moment, the teeth were subdivided into two groups of 20 specimens each, because of the final irrigation method used: I – irrigation with EDTA at 17% for 3min and II – identical protocol, thus, after EDTA aspiration at17%, it was again irrigated with chlorhexidine digluconate at 2%, also kept intra-canal for 3min. Each group was again sub-divided into two sub-groups (ten teeth each), according to the cement used (Sealer 26TM or SealapexTM), and filled by using a single gutta-percha F1 (ProTaperTM, Universal Filling), in such a manner that it goes 2.0 mm beyond the radicular apex. Soon after that, the teeth were immersed in Rhodamine BTM for 72h, vacuum and after the roots have been bucolingually grooved, the leakages marked were measured with program Image ToolTM. Results and Conclusions: The leakage magnitude was similar among themselves (p > 0.05), except for group Sealapex®, thus the final use with chlorhexidine reduced apical leakage (p < 0.05).

Marginal adaptation of Class V restorations with current generation dentin-bonding agents: effect of different dentin surface treatments.

This study sought to assess the use of chlorhexidine with several excipients as a dentin surface treatment and its effect on marginal adaptation of class V restorations with current-generation dentin bonding agents. A total of 120 human third molars were selected and allocated into 12 groups, with standardized buccal class V restorations randomly divided into preconditioned dentin rinsed with: water; water + chlorhexidine; ethanol; or ethanol + chlorhexidine. After rinsing of dentin (previously conditioned with 35% phosphoric acid) with the test solutions, the Adper single bond 2, prime and bond 2.1, and Excite bonding systems were applied randomly. Restorations were performed with FiltekTM Z350 XT composite resin. The resulting specimens were subjected to thermal and mechanical load cycling. Quantitative analysis of marginal adaptation was performed on epoxy replicas by means of scanning electron microscopy. Results were assessed by means of the Kruskal-Wallis test (percentages of continuous margins) and Wilcoxon test (differences between percentages of continuous margins before and after thermal cycling and mechanical loading), at a significance level of p < 0.05. Outcomes in the chlorhexidine-treated groups were not superior to those obtained with other treatments.

Reliability of marginal microleakage assessment by visual and digital methods

The aim of this study was to investigate the reliability of visual and digital methods to assess marginal microleakage in vitro. Materials and Methods: Typical Class V preparations were made in bovine teeth and filled with composite resin. After dye penetration (0.5% basic fuchsin), teeth were sectioned and the 53 obtained fragments were assessed according to visual (stereomicroscope) and digital methods (Image Tool Software ® -ITS) (University of Texas Health Science Center-San Antonio Dental School, USA). Two calibrated examiners (A and B) evaluated dye penetration, by means of a stereomicroscope with ×20 magnification (scores), and by the ITS (millimeters). The intra- and inter-examiner agreement was estimated according to Kappa statistics (κ), and intraclass correlation coefficient (ρ). Results: In relation to the visual method, the intra-examiner agreement was almost perfect (κA = 0.87) and substantial (κB = 0.76), respectively to the examiner A and B. The inter-examiner agreement showed an almost perfect reliability (κ = 0.84). For the digital method, the intra-examiner agreement was almost perfect for both examiners and equal to ρ = 0.99, and so was the inter-examiner agreement value. Conclusion: Visual (stereomicroscope) and digital methods (ITS) showed high levels of intra- and inter-examiner reproducibility when marginal microleakage was assessed.

A identidade da literatura marginal em enunciados verbo-visuais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência de técnicas de moldagem e de dois vazamentos na precisão dimensional de modelos de gesso e adaptação marginal de infraestruturas CAD/CAM em Y-TZP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Does water level affect benthic macro-invertebrates of a marginal lake in a tropical river-reservoir transition zone?

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Clinical/photographic evaluation of a single application of two sealants after eleven years

The clinical behavior of Concise and Prisma Shield sealants for pit and fissure was analyzed by clinical/photographic evaluation. A hematoxylin-based staining solution was applied to the occlusal surface 7 days, 18 months, 36 months, and 11 years after the occlusal sealing, thus allowing the sealant material on the surface to be checked. At each analysis time, each occlusal surface was photographed, and the photographs corresponding to each time were submitted to clinical/photographic evaluation. Although the sealant materials showed marginal alterations over time, they did not require reapplication because the region composed of the pit and fissure remained covered.

Porosity and sealing ability of root fillings with gutta-percha and BioRoot RCS or AH Plus sealers. Evaluation by three ex vivo methods

To investigate the ability of BioRoot RCS, a tricalcium silicate-based root canal sealer and AH Plus to effectively fill the root canals of contralateral teeth using three evaluation methods, and to investigate also the correlation between the methods. The prepared root canals of ten pairs of contralateral mandibular premolar teeth were filled with gutta-percha and sealer using lateral compaction. The percentage of voids within the root canal was assessed by micro-computed tomography, whilst sealing ability was investigated by fluid transport and leakage of fluorescent microspheres. The interaction of sealer with dentine, and sealer penetration were assessed by confocal microscopy. The void volume, fluid flow, microsphere leakage and sealer interaction with dentine for both materials were compared. Nonparametric (Mann-Whitney) tests were used to compare the % void and fluid transport of the two sealers. Spearman correlation was used to assess the pairwise relationships between the techniques. The level of significance was set to 0.05. BioRoot RCS exhibited significantly more percentage of voids than AH Plus. There was no difference in fluid flow and microsphere penetration. BioRoot RCS exhibited a different pattern of sealer penetration and interaction with the dentine walls compared to AH Plus. For both materials, the pairwise correlations between the three techniques were close to zero, indicating weak relationships. MicroCT analysis revealed a higher void volume for BioRoot RCS. The other techniques did not show a difference between the sealing ability of the sealers. The correlation between the three ex vivo methods of assessment was weak demonstrating their complementarity rather than their concordance.

Marginal deterioration of the silicone for facial prosthesis with pigments after effect of storage period and chemical disinfection

The failure of facial prostheses is caused by limitations in the properties of existing materials, especially flexibility and durability. Therefore, this study evaluated the marginal deterioration of a silicone used for fabrication of facial prostheses (Silastic MDX4-4210, Dow Corning Corporation, Midland, MI, USA) according to the influence of artificial aging, daily disinfection, and 2 types of pigmentation. Thirty specimens were fabricated and subdivided in 6 groups: without pigmentation, pigmented with make-up powder and iron oxide, and evaluated with and without the action of the disinfectant. Analysis of marginal deterioration was performed on a scanning electron microscope (magnification, ×5000) immediately 6 months and 1 year after fabrication of specimens, following the guidelines of ASTM International. After visual analysis of the photomicrographs, it was noticed that all groups presented marginal deterioration and alterations in surface texture with time. The use of disinfection did not contribute to the marginal deterioration of polymer (silicone), regardless of the pigmentation and artificial aging.

Avaliação da infiltração marginal de três cimentos endodônticos após preparo para retentor de acordo com o momento do preparo

Objetivo: o objetivo desse estudo in vitro foi avaliar a infiltração marginal coronária após o preparo para retentor em dentes obturados com três diferentes cimentos, de acordo com o período entre a obturação do canal radicular e o preparo para retentor. Métodos: Noventa dentes humanos recentemente extraídos foram limpos e instrumentados e, então, obturados com Sealapex, Endométhasone ou TopSeal. Brocas Gates-Glidden foram utilizadas para o preparo imediato de 10 dentes de cada cimento até manter 5mm de obturação remanescente. Sessenta raízes obturadas foram incubadas a 37°C em meio úmido por 30 e 60 dias para serem, depois, preparadas para os retentores como descrito anteriormente. A superfície externa de cada raiz foi coberta com Araldite. Os espécimes foram imersos em corante azul de metileno a 2% sob vácuo por 24h, para então poderem ser analisados. A infiltração foi mensurada pelo software Sigma Scan da parte superior da obturação à porção apical alcançada pelo corante. Resultado: o Sealapex e o TopSeal apresentaram menor infiltração após o preparo para retentor do que o Endométhasone. O preparo imediato para o retentor apresentou menor infiltração do que o preparo para o retentor após 30 e 60 dias da obturação do canal radicular.

Germination of Cochlospermum regium Seeds: Influence of Seed Size, Vials, Vial Sealing In vitro, and Substrate In vivo

Aims: This work aimed to assess how seed size, vials, vial sealing (in vitro), and substrate (in vivo) affect C. regium germination and emergence. This study shall contribute to the viable production of C. regium seedlings. Study Design: The experimental design used in these experiments was randomized. Place and Duration of Study: Department of Plant Biotechnology, Universidade de RibeirãoPreto, between March 2010 and December 2010. Methodology: This work has evaluated how seed size, vials, vial sealing (in vitro), and substrate (in vivo) influence the germination and emergence of C. regium. Results: The results showed that cultivation of C. regium seedlings from seeds is viable, irrespective of seed size. Vial oxygenation is an important parameter to consider in vitro, to obtain a larger number of normal seedlings. As for in vivo conditions, germination should be conducted in sand, to ensure a greater amount of young seedlings. Conclusion: The results presented here attested that it is possible to produce C. regium seedlings from seeds of any size both in vivo and in vitro conditions. In vitro, it is important to consider vial oxygenation, in order to obtain a greater amount of normal seedlings. In vivo, germination should be conducted in sand, to ensure production of a large quantity of seedlings.

Análise da efetividade de polimerização, adaptação marginal e interna de restaurações Classe II de resinas compostas de inserção em bloco utilizando diferentes matrizes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Colonização bacteriana na região marginal de restaurações cerâmicas: efeito do método de remoção do cimento e do polimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)