scholarly journals Micromorphological characterization of adhesive interface of sound dentin and total-etch and self-etch adhesives

2015 ◽  
Vol 68 (1-2) ◽  
pp. 10-16
Author(s):  
Milan Drobac ◽  
Igor Stojanac ◽  
Bojana Ramic ◽  
Milica Premovic ◽  
Ljubomir Petrovic

Introduction. The ultimate goal in restorative dentistry has always been to achieve strong and permanent bond between the dental tissues and filling materials. It is not easy to achieve this task because the bonding process is different for enamel and dentin - dentin is more humid and more organic than enamel. It is moisture and organic nature of dentin that make this hard tissue very complex to achieve adhesive bond. One of the first and most widely used tools for examining the adhesive bond between hard dental tissues and composite restorative materials is scanning electron microscopy. The aim of this study was scanning electron microscopy analyzes the interfacial micro morphology of total-etch and self-etch adhesives. Material and Methods. Micro morphological characteristics of interface between totaletch adhesive (Prime & Bond NT) in combination with the corresponding composite (Ceram X Mono) were compared with those of self-etching adhesive (AdheSE One) in combination with the corresponding composite (Tetric EvoCeram). The specimens were observed under 1000 x magnification of scanning electron microscopy (JEOL, JSM-6460 Low Vacuum). Measurement of the thickness of the hybrid layer of the examined composite systems was performed with the software of the device used (NIH Image ?nalyser). Results. Micromorphological analysis of interface showed that the hybrid layer in sound dentin was well formed, its average thickness being 2.68 ?m, with a large number of resin tags and a large amount of lateral branches for specimens with a composite system Prime & Bond NT - Ceram X Mono. However, the specimens with composite systems Adhese One - Tetric EvoCeram did not show the presence of hybrid layer and the resin tags were poorly represented. Conclusion. The results of this study suggest that total-etch adhesives bond better with sound dentin than self-etch adhesives.

Author(s):  
M. L. Zimny ◽  
A. C. Haller

During hibernation the ground squirrel is immobile, body temperature reduced and metabolism depressed. Hibernation has been shown to affect dental tissues varying degrees, although not much work has been done in this area. In limited studies, it has been shown that hibernation results in (1) mobilization of bone minerals; (2) deficient dentinogenesis and degeneration of alveolar bone; (3) presence of calculus and tears in the cementum; and (4) aggrevation of caries and pulpal and apical tooth abscesses. The purpose of this investigation was to study the effects of hibernation on dental tissues employing scanning electron microscopy (SEM) and related x-ray analyses.


2017 ◽  
Vol 41 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Marwa Abdel Hafez ◽  
Mona Elkateb ◽  
Sonia El Shabrawy ◽  
Amel Mahmoud ◽  
Omar El Meligy

Aim: To evaluate the microleakage of composite restorations following Papain-based chemo-mechanical caries removal compared to the conventional drilling method. The characteristic of the hybrid layer was also studied using scanning electron microscopy. Study design: The sample included thirty freshly extracted and exfoliated primary molars with open proximal carious dentin lesions. Teeth were divided into two equal groups, according to method of caries removal. Following caries removal, cavity preparations were restored with composite resin. After thermocycling, teeth were sealed apically and coated with nail polish except the surface of restorations and the surrounding 1mm. Teeth were immersed in basic fuschin dye solution, then they were sectioned mesiodistally. The extent of dye penetration was detected using a light stereomicroscope. After microleakage test, the resin/dentin interface was examined using scanning electron microscopy. Results: There was no significant difference in the degree of leakage between both groups. In the Papacarie group, longer and numerous resin tags were observed with statistically significant thicker hybrid layer than those following the drilling method. However, there was no significant difference between the diameters of resin tags of both groups. Conclusions: Papacarie does not adversely affect the microleakage of composite restorations and provides a suitable surface for bonding.


2011 ◽  
Vol 37 (9) ◽  
pp. 1316-1319 ◽  
Author(s):  
Noushin Shokouhinejad ◽  
Mohammad Sabeti ◽  
Hedayat Gorjestani ◽  
Mohammad Ali Saghiri ◽  
Mehrdad Lotfi ◽  
...  

2020 ◽  
Vol 57 (5) ◽  
pp. 1447-1458 ◽  
Author(s):  
Fernando de Freitas Fernandes ◽  
Ana Cristina Bahia ◽  
Nágila Francinete Costa Secundino ◽  
Paulo Filemon Paolucci Pimenta

Abstract The ultrastructure of the mouthparts of Haematobia irritans (L.) was investigated by scanning electron microscopy. The morphological characteristics of the maxillary palps, labium (prementum and postmentum), labrum, hypopharynx, haustellum, and labellar lobes are described, as well as of the sensilla evidenced on all the surface of the mouthparts, and the set of different positions assumed by the mouth apparatus of this fly. Based on their morphology, 12 well-differentiated sensilla were identified, among three types of cuticular sensilla: trichoidea, coeloconica, and campaniformia. A slight sexual dimorphism in the sensilla patterns found in the mouthparts of H. irritans was evidenced. These observations are discussed with reference to the current literature on the functional morphology of sense organs of Insecta. These results could facilitate the recognition of the chemosensory sensilla by electrophysiological techniques, and foment future taxonomic and phylogenetic studies to better elucidate the evolution of Diptera, Muscomorpha.


Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2948
Author(s):  
Rana S Al-Hamdan ◽  
Basil Almutairi ◽  
Hiba F Kattan ◽  
Noura A. Alsuwailem ◽  
Imran Farooq ◽  
...  

An experimental adhesive incorporated with different nano-hydroxyapatite (n-HA) particle concentrations was synthesized and analyzed for dentin interaction, micro-tensile bond strength (μTBS), and degree of conversion (DC). n-HA powder (5 wt % and 10 wt %) were added in adhesive to yield three groups; gp-1: control experimental adhesive (CEA, 0 wt % HA), gp-2: 5 wt % n-HA (HAA-5%), and gp-3: 10 wt % n-HA (HAA-10%). The morphology of n-HA spheres was evaluated using Scanning Electron Microscopy (SEM). Their interaction in the adhesives was identified with SEM, Energy-Dispersive X-ray (EDX), and Micro-Raman spectroscopy. Teeth were sectioned, divided in study groups, and assessed for μTBS and failure mode. Employing Fourier Transform-Infrared (FTIR) spectroscopy, the DC of the adhesives was assessed. EDX mapping revealed the occurrence of oxygen, calcium, and phosphorus in the HAA-5% and HAA-10% groups. HAA-5% had the greatest μTBS values followed by HAA-10%. The presence of apatite was shown by FTIR spectra and Micro-Raman demonstrated phosphate and carbonate groups for n-HA spheres. The highest DC was observed for the CEA group followed by HAA-5%. n-HA spheres exhibited dentin interaction and formed a hybrid layer with resin tags. HAA-5% demonstrated superior μTBS compared with HAA-10% and control adhesive. The DC for HAA-5% was comparable to control adhesive.


Cancers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 416 ◽  
Author(s):  
Afroditi Nanou ◽  
Mateus Crespo ◽  
Penny Flohr ◽  
Johann De Bono ◽  
Leon Terstappen

To explore morphological features of circulating tumor cells (CTCs) and tumor-derived extracellular vesicles (tdEVs), we developed a protocol for scanning electron microscopy (SEM) of CTCs and tdEVs. CTCs and tdEVs were isolated by immunomagnetic enrichment based on their Epithelial Cell Adhesion Molecule (EpCAM) expression or by physical separation through 5 μm microsieves from 7.5 mL of blood from Castration-Resistant Prostate Cancer (CRPC) patients. Protocols were optimized using blood samples of healthy donors spiked with PC3 and LNCaP cell lines. CTCs and tdEVs were identified among the enriched cells by fluorescence microscopy. The positions of DNA+, CK+, CD45− CTCs and DNA−, CK+, CD45− tdEVs on the CellSearch cartridges and microsieves were recorded. After gradual dehydration and chemical drying, the regions of interest were imaged by SEM. CellSearch CTCs retained their morphology revealing various shapes, some of which were clearly associated with CTCs undergoing apoptosis. The ferrofluid was clearly distinguishable, shielding major portions of all isolated objects. CTCs and leukocytes on microsieves were clearly visible, but revealed physical damage attributed to the physical forces that cells exhibit while entering one or multiple pores. tdEVs could not be identified on the microsieves as they passed through the pores. Insights on the underlying mechanism of each isolation technique could be obtained. Complete detailed morphological characteristics of CTCs are, however, masked by both techniques.


2011 ◽  
Vol 91 (8) ◽  
pp. 1617-1625 ◽  
Author(s):  
M.P. Sal Moyano ◽  
M.A. Gavio ◽  
E.I. Cuartas

Functional morphology of the male gonopods, female holding systems and vulvae of Libinia spinosa are described using scanning electron microscopy and histological sections, establishing differences between immature and mature individuals. The first gonopod of mature males, larger than 35.1 mm of carapace width (CW), is long, slender, and ending in two wing-like processes; abdominal, characterized by the presence of a sub-terminal seminal canal, and sternal, closed and where the cuticle holds setae. In immature males, smaller than 29.9 mm CW, both processes are shorter, and the tip of the abdominal process closed. Six different types of setae are described for both gonopods. Internally, the gonopods have rosette glands in immature and mature individuals. The presence of secretions, which may be involved in the moulting process, was observed in immature males towards the external cuticle corresponding to the rosette glands. The rosette glands may be related to reproduction in mature males. Females presented a press-button holding system and a biconcave vulva. In immature females, smaller than 36.1 mm CW, the vulva aperture was closed by integument bulging to the outside. In mature females, larger than 42.6 mm CW, the locking system was almost fused to the cuticle, and the vulvae showed an open biconcave form with a more inner flexible membrane. Morphological characteristics shown by the gonopods of mature males develop synchronously with the acquisition of physiological maturity, not with morphometrical maturity. The mature holding systems and vulvae of females are developed synchronously with physiological and morphometrical maturity.


2019 ◽  
Vol 20 (2) ◽  
pp. 522-534
Author(s):  
T. Balinyan ◽  
L. Derecha ◽  
Yu. Nosatenko

The article considers the need for a comprehensive study of biological damage to fibrous materials by scanning electron microscopy. The main types and characteristics of fibers and fibrous materials, their types of damage, in particular, biological, and the mechanism of their formation are described. It is shown that with modern methods for studying morphological characteristics, the most effective is the method of scanning electron microscopy, which makes it possible to directly study the object in a wide range of magnifications. The use of scanning electron microscopy makes it possible to identify qualitatively new volumetric microsigns when conducting studies of fibrous materials. Biological damage agents (biofactors) are considered — microbiological (bacteria, microbes, fungi, blue-green algae), phytological (mosses, lichens, higher plants, algae), zoological (insects, birds, mammals). Attention is focused on the study of injuries caused by mold caused by moths, dogs, etc. Conducting a comprehensive study of various types of damage to materials of various fibrous nature allows us to obtain an information database, the possibility of differentiating chemical, mechanical, thermal and biological damage, identifying microsigns that individualize one or another object (factor) of action, influence, increasing the potential for obtaining trace information about the actual data and circumstances of the event in those cases when only by external morphological features of the diagnosis It is not possible to repair damage. The data obtained indicate the effectiveness of the chosen research area. The results of the studies are positive for creating the optimal research scheme, methods of microscopic studies of damage to materials of fibrous nature in order to solve diagnostic, identification and situational tasks of forensic examination.


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