A scanning electron microscopy study of diseased root surfaces conditioned with EDTA gel plus Cetavlon after scaling and root planing

In the present investigation, a scanning electron microscopy analysis was performed to evaluate the effects of the topical application of ethylenediaminetetraacetic acid (EDTA) gel associated with Cetavlon (EDTAC) in removing the smear layer and exposing collagen fibers following root surface instrumentation. Twenty-eight teeth from adult humans, single rooted and scheduled for extraction due to periodontal reasons, were selected. Each tooth was submitted to manual (scaling and root planing) instrumentation alone or combined with ultrasonic instruments, with or without etching using a 24% EDTAC gel. Following extraction, specimens were processed and examined under a scanning electron microscope. A comparative morphological semi-quantitative analysis was performed; the intensity of the smear layer and the decalcification of cementum and dentinal surfaces were graded in 12 sets using an arbitrary scale ranging from 1 (area covered by a smear layer) to 4 (no smear layer). Root debridement with hand instruments alone or combined with ultrasonic instruments resulted in a similar smear layer covering the root surfaces. The smear layer was successfully removed from the surfaces treated with EDTAC, which exhibited numerous exposed dentinal tubules and collagen fibers. This study supports the hypothesis that manual instrumentation alone or instrumentation combined with ultrasonic instrumentation is unable to remove the smear layer, whereas the subsequent topical application of EDTAC gel effectively removes the smear layer, uncovers dentinal openings and exposes collagen fibers.

Scanning electron microscopy evaluation of the hard tissue barrier after pulp capping with calcium hydroxide, mineral trioxide aggregate (MTA) or ProRoot MTA

The aim of this study was to investigate the morphology and localisation of calcium hydroxide- and mineral trioxide aggregate (MTA)-induced hard tissue barriers after pulpotomy in dogs' teeth. Pulpotomies were performed on maxillary and mandibular premolars of five dogs. The teeth were assigned into three groups according to the pulp-capping agent used. The pulpal wounds were capped with calcium hydroxide (Ca(OH)(2) - control), MTA or ProRoot MTA, and the cavities were restored with amalgam. After a 90-day follow-up period, the dogs were euthanised and the teeth were examined under scanning electron microscopy (SEM). An image-processing and analysis software was used to delimit the perimeters of the root canal area and the hard tissue barrier to determine the percentage of root canal obliteration. SEM data were used to assess the morphology, localisation and extension of the reparative hard tissue barriers. ProRoot MTA was statistically different from MTA and Ca(OH)(2) (P < 0.05) regarding tissue barrier morphology. Localisation data showed that ProRoot MTA was significantly different from Ca(OH)(2) (P < 0.05) and similar to MTA (P > 0.01; P > 0.05). No statistically significant difference (P > 0.01; P > 0.05) was observed between MTA and Ca(OH)(2). A larger number of complete (centroperipheral) hard tissue barriers with predominance of dentinal tubules was observed to the ProRoot MTA when compared with the Ca(OH)(2) group.

Residues of calcium hydroxide-based intracanal medication associated with different vehicles: A scanning electron microscopy evaluation

This study evaluated the presence of residues after removal of calcium hydroxide [Ca(OH)2] associated with different vehicles. Thirty single-rooted teeth were instrumented to a master apical file #25 using 2.5% NaOCl as main irrigant and 17% trisodium EDTA (ethylenediaminetetraacetic acid) as final agent irrigant. Then, the root canals were dressed with Ca(OH)2 associated with silicone oil (Group 1), 2% chlorhexidine gluconate (Group 2), or propylene glycol (Group 3). After coronal sealing, all teeth were kept in a moist environment at room temperature. After 7 days, the teeth were reopened and medicaments were removed using 5 mL of saline solution and instrumentation with master apical file followed by new irrigation with 5 mL of 2.5% NaOCl. Subsequently, teeth were split longitudinally and assessed by scanning electron microscopy. The wall cleanliness of the cervical and apical thirds of the roots were evaluated and scored by three blinded examiners. Statistical analysis was performed using KruskalWallis and Wilcoxon tests at 5% level of significance. All roots had residues of Ca(OH)2 on the canal walls. All experimental groups had similar results (P > 0.05) regardless of the third evaluated. There was significant difference between the apical and cervical thirds only in Group 3 (P < 0.05). Association of different vehicles to Ca(OH)2 does not influence the persistence of residues on the root canal walls. Microsc. Res. Tech. 2012. (C) 2012 Wiley Periodicals, Inc.

Mesoscopy and scanning electron microscopy of the trabecular projections in the superior sagittal sinus

The trabecular projections of the human superior sagittal sinus were classified into types and subtypes according to spatial arrangement and shape. The horizontal and vertical projections direct laminar blood flow, while the conic type, which is avalvular, protects the openings of the superior cerebral veins in the superior sagittal sinus. Copyright (C) 2003 S. Karger AG, Basel.

3D reconstruction and scanning electron microscopy of salivary glands of the millipede Rhinocricus padbergi (Verhoef, 1938) (Diplopoda: Spirobolida)

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

Analysis of Tooth Enamel After Excessive Bleaching: A Study Using Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy

This study assessed alterations on bovine enamel after excessive bleaching. Coronal portions of bovine teeth (n = 30) were sectioned and divided into three groups (n = 10 per group). The coronal parts were further cut incisocervically into two halves. While one half received no bleaching (control), the other half was subjected to either one (group 1), three (group 2), or five bleaching sessions (group 3) with 35% hydrogen peroxide. The enamel surfaces were then analyzed using scanning electron microscopy and energy dispersive x-ray spectroscopy (EDS). Fxcessive bleaching affected the surface morphology and chemistry of the bovine enamel. EDS analysis showed the highest decrease in calcium ion percentages in groups 2 and 3 when compared to their nonbleached halves. Oxygen and phosphorus percentages were comparable on both the control and bleached enamel, regardless of the number of bleaching sessions. Consecutive bleaching sessions with 35% hydrogen peroxide may lead to morphologic and specific elemental changes when performed in a short period of time. Calcium ion percentages may decrease when this bleaching agent is used for more than one session. Int J Prosthodontics 2010;23:29-32.

Characterization of the external female genitalia of six species of Triatominae (Hemiptera: Reduviidade) by scanning electron microscopy

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

A study of the scutellum in eight Chagas disease vector species from genus Triatoma (Hemiptera, Reduviidae) using optical and scanning electron microscopy

The aim of this study was to analyze the external morphology of the scutellum through optical microscopy and scanning electron microscopy (SEM) in male specimens of Triatoma costalimai, T. delpontei, T. eratyrusiformis, T. matogrossensis, T. infestans melanosoma, T. sherlocki, T. tibiamaculata, and T. vandae. A total of 30 photographs of the scutellum were made. Magnification varied from 50X to 750X. Regarding depth and forms of the central depression, the heart-shaped form was predominant, with some exceptions, so that this shape appears to be a common characteristic for species of genus Triatoma Laporte, 1832. In T. eratyrusiformis, a kind of sensillum with important taxonomic value was observed. The different sizes and shapes of the designs found on the posterior process of the scutellum were also of important taxonomic interest. The study of the scutellum based on SEM showed valuable characteristics, allowing the use of this structure to aid the diagnosis of triatomine species. Thus, more specimens in subsequent studies and analyses of morphometric parameters should contribute to agreement on phylogenetic aspects in this genus. A Key to eight species of Triatoma based on male scutellar morphology is presented.

Scanning electron microscopy of the corneal endothelium of ostrich

Objetivou-se examinar a superfície posterior do endotélio corneano e realizar análise morfométrica das células endoteliais da córnea de avestruz (Struthio camelus) valendo-se da microscopia eletrônica de varredura. Avaliaram-se o número de lados, a área celular média, a densidade celular e o coeficiente de variação da área celular. O endotélio corneano de avestruz constitui-se de células poligonais uniformes em tamanho e forma, e com poucas interdigitações das bordas celulares. Visibilizaram-se microvilosidades na superfície celular. A área celular média foi de 269±18µm² e a densidade celular foi de 3717±240 células mm-2. O coeficiente de variação foi de 0,06 e o percentual de células hexagonais de 75%. Não foram observadas diferenças significativas entre os parâmetros avaliados entre os olhos esquerdo e direito. Este estudo demonstrou que o endotélio corneano de avestruz é semelhante ao descrito em outros vertebrados.

Study of the biodegradation of a polymer derived from castor oil by scanning electron microscopy, thermogravimetry and infrared spectroscopy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Morphometric analysis of the corneal endothelium of Yacare caiman (Caiman yacare) using scanning electron microscopy

The objective of this study was to examine the endothelial surface morphology and to perform morphometric analysis of the corneal endothelial cells of Yacare caiman (Caiman yacare) using scanning electron microscopy. Morphometric analysis with regard to polygonality, mean cell area, cell density and coefficient of variation of mean cell area was performed. Cell areas were measured using image analysis software. The normal corneal endothelium of Yacare caiman consisted of polygonal cells of uniform size and shape with interdigitations of the cell borders. Microvilli appeared as protrusions on the cellular surface. The average cell area was 270 +/- 24 mum(2) and the endothelial cell density was 3704 +/- 324 cells/mm(2). The coefficient of variation of cell area was 0.22. This study demonstrates that the Yacare caiman corneal endothelium is similar to those described in other vertebrates.