scholarly journals Antibacterial and Bonding Properties of Universal Adhesive Dental Polymers Doped with Pyrogallol

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1538
Author(s):  
Naji Kharouf ◽  
Ammar Eid ◽  
Louis Hardan ◽  
Rim Bourgi ◽  
Youri Arntz ◽  
...  

This study investigated the antibacterial activity, bond strength to dentin (SBS), and ultra-morphology of the polymer–dentin interface of experimental adhesive systems doped with pyrogallol (PY), which is a ubiquitous phenolic moiety that is present in flavonoids and polyphenols. A universal adhesive containing 4-META and 10-MDP was used in this study. PY behaves as an antioxidant and anti-cancerogenic agent and it was incorporated into the adhesive at different concentrations (0.5 and 1 wt.%). The antibacterial activity and SBS were analyzed and the results were statistically analyzed. The ultra-morphology of the polymer–dentin interface was assessed using scanning electron microscopy (SEM). At 24 h, a lower antibacterial activity was observed for the control adhesive compared to those with 0.5% and 1% PY. No difference was seen in SBS between the three groups at 24 h. After 6 months, the SBS of the 0.5% PY adhesive was significantly lower than the other tested adhesives. The specimens created with 1% PY adhesive presented a higher bond strength at six months compared with that found at 24 h. No morphological differences were found at the polymer–dentin interfaces of the tested adhesives. Pyrogallol may be incorporated into modern universal adhesive systems to preserve the polymer–dentin bonding interface and confer a certain degree of antibacterial activity.

Weed Science ◽  
1978 ◽  
Vol 26 (6) ◽  
pp. 619-625 ◽  
Author(s):  
R. E. Hoagland ◽  
R. N. Paul

A comparative scanning electron microscopy (SEM) study was performed on the surfaces of seeds and coleoptiles of several conspecific rice(Oryza sativaL.) varieties including the weed red rice and several cultivars: Mochi-Gommi and LA-110 (medium grained); Starbonnet, Labelle, and Bluebelle (long grained). Seed surfaces of red rice, LA-110 and Mochi-Gommi possessed trichomes that were more numerous at the seed apex than on other seed parts. Red rice also exhibited a large central awn extending from the seed apex. This awn had spines along its axis and numerous spines at its apical end. These characteristics were absent in the other varieties. No significant differences were noted in the seed-surface tubercles and in the quantity or structure of wax on the seed surface in all six samples. The coleoptiles of all samples had several similarities: the stomata were arranged in parallel rows on both the adaxial and abaxial surfaces, the epicuticular wax structure on both surfaces was rodlet, prickle hairs were found on the adaxial coleoptile surface (but absent on abaxial), spines were present on the edge of the apical end (older portion) and decreased in number toward the basal end (younger portion), and two types of papillae (based on size and shape) were present on both the adaxial and abaxial surfaces. Although there were varietal differences among developing coleoptiles on a macroscopic scale, significant morphological differences were not discernible at the SEM level.


2011 ◽  
Vol 143 (2) ◽  
pp. 126-135 ◽  
Author(s):  
Zhaofu Yang ◽  
Yalin Zhang

AbstractScanning electron microscopy on the ultrastructure of scales on the forewings and labial palpi suggests species-diagnostic differences among six sibling species of the genus Ostrinia Hübner. Among four species with small mid-tibiae, O. furnacalis (Guenée) and O. nubilalis (Hübner) show similar ultrastructure of the distal forewing scales, which is distinctly different from that of O. orientalis Mutuura and Munroe and O. dorsivittata (Moore). The diameter of windows between longitudinal ridges and cross ribs of forewing scales in O. dorsivittata is the largest among examined species, and clearly different from that in the other three small mid-tibiae species. Scales of the labial palpi of O. orientalis have indistinct vestigial windows; windows of O. nubilalis are more numerous and larger than in the other three small mid-tibiae species. Among two species with massive mid-tibiae, window diameter of forewing scales is larger in O. zealis (Guenée) than in O. scapulalis (Walker). Moreover, the number and diameter of windows in scales of the labial palpi differs between these two species. In addition to other known morphological differences, these ultrastructural differences provide further evidence that closely related Ostrinia species are distinct.


2017 ◽  
Vol 19 (2) ◽  
pp. 47
Author(s):  
Daphne Ross DDS ◽  
Carlos E. Filloy Esna DDS ◽  
Juan Carlos Ramírez-Barrantes DDS, MSD, PhD

Currently there is controversy in the literature about clinical and adhesive effectiveness with respect to adhesive systems aimed to  root reinforcement. Thus, the objective of this study was to evaluate the Push-Out bond strength between the Rebilda® post system and the intraradicular dentine. Thus, 28 unirradicular teeth were used, cut and standardized in 16 mm. The root segments were submitted to endodontic treatment; and then randomly divided into two groups, Group 1 (n = 14): Rebilda® DC + Futurabond DC; Group 2 (n = 14): RelyX ARC + Adper Scothbond Multipurpose Plus. Ten specimens from each group were submitted  to the Push-Out Test. The remaining 4 specimens from each group were prepared for Scanning Electron Microscopy (SEM) in order to evaluate the formation of resinous extensions at the post-cement-dentin interface. Group 2 showed better results when compared to Group 1 regarding bond strength and in formation of resinous extensions or tags, but there was no statistically significant difference (p>0.05). It was concluded that the REBILDA® Post System promotes adequate bond strength to intraradicular dentin.


2005 ◽  
Vol 75B (1) ◽  
pp. 158-167 ◽  
Author(s):  
Fábio Barbosa de Souza ◽  
Cláudio Heliomar Vicente Silva ◽  
Regina Guenka Palma Dibb ◽  
Carina Sincler Delfino ◽  
Lúcia Carneiro de Souza Beatrice

2021 ◽  
Vol 11 (2) ◽  
pp. 54-61
Author(s):  
Fatih Demirci ◽  
Samet Tekin

Aim: In this in vitro study, the effect of two adhesive systems applied to surfaces of different polyether-ether-ketone (PEEK) composites on the shear bond strength (SBS) of a composite resin was compared. Methodology: Eighty PEEK specimens were divided into four groups (n=20): Unfilled PEEK (UF), carbon-fiber-reinforced PEEK (CFR), glass-fiber-reinforced PEEK (GFR), and ceramic-reinforced PEEK (CR). Each group was further divided into two subgroups (n=10): Visio.link (VL) and Single Bond Universal (SB). The specimens with 8-mm diameter and 5-mm thickness were prepared. SBS was examined using a universal testing machine. Results were statistically analyzed by multivariate analysis of variance and Tukey’s post-hoc test. Failure modes were analyzed using a stereomicroscope at 20× magnification. Surface properties were examined by scanning electron microscopy. The surface properties of the specimens were examined by scanning electron microscopy (SEM).  Results: Effect of different PEEK and adhesive systems on SBS was found to be statistically significant (p<0.05). SBS values for CFR-VL and UF-VL groups were statistically more significant than those for CFR-SB and UF-SB groups (p=0.001). SBS values for the GFR-VL group were statistically more significant than that for the UF-VL group (p=0.001). SBS values for the CF-SB group were statistically more significant than those for CFR-SB and CFR-SB groups (p=0.001). Failure modes were examined using a stereomicroscope at 20× magnification, and adhesive and mixed failure modes were observed. Conclusion: PEEK composites with different contents and properties can be used in fixed prosthetic restorations. However, additional experimental and clinical studies are required to investigate different PEEK frameworks and composite veneers.   How to cite this article: Demirci F, Tekin S. Comparison of two adhesive systems of various polyetheretherketone (PEEK) composites on the shear bond strength. Int Dent Res 2021;11(2):54-61. https://doi.org/10.5577/intdentres.2021.vol11.no2.1   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.


2020 ◽  
Vol 23 (4) ◽  
pp. 12p
Author(s):  
Pinar Cevik ◽  
Arzu Zeynep Yildirim ◽  
Zafer Artvin ◽  
Mutlu Özcan

Objective: The aim of this study was to evaluate and compare the microtensile bond strengths of four current adhesive materials that contain different monomers at deep and superficial dentin. Material and Methods: Forty non-carious human third molars (n = 5) were used in the study. Specimens were divided into two main groups according to dentin thickness as superficial and deep dentin. Groups were further divided into four subgroups in terms of the adhesive systems used: Nova Compo B Plus (NCBP), Nova Compo B (NCB), Futurabond M (FB) and Clearfil S3 Bond Plus (CS3). All specimens were bonded to resin composite and stored in 37 °C water for 9-months. Teeth were sectioned into 3 x 3 mm x 1mm thick beams. Microtensile bond strength test was carried out by using a universal testing device (1 mm/min). After fracture, failure types were observed using an optical microscope and the fractured dentin surfaces were observed by a scanning electron microscopy (SEM). One-way ANOVA and Tukey tests were used to compare the adhesive system in each dentin group. An unpaired T-test was used to compare the dentin thickness in each adhesive material. Results: As compared to deep dentin, superficial dentin showed higher µTBS values in groups NCBP, FB and CS, as opposed to group NCB. Only NCB revealed higher bond strength at deep dentin layers when compared to superficial dentin. In the superficial dentin group, NCBP showed the highest bond strength value, while NCB showed the lowest bond strength. In the deep dentin group, while NCB showed the highest bond strength value, NCBP revealed the lowest bond strength value after 9-months storage. While 4-META and 10-MDP monomer combination (NCBP) resulted in the highest bond strength value among the adhesive systems in the superficial dentin group, the monomer combination (NCB) resulted in the highest bond strength in deep dentin group. Conclusions: Microtensile bond strength performance are affected by both the type of monomer in the adhesive combination and the depth of the dentin. KEYWORDS Adhesive system; dentin thickness; hydrophobic monomer; microtensile bond strength; scanning electron microscopy.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Buzuayehu Abebe ◽  
Enyew Amare Zereffa ◽  
Aschalew Tadesse ◽  
H. C. Ananda Murthy

Abstract Metal oxide nanomaterials are one of the preferences as antibacterial active materials. Due to its distinctive electronic configuration and suitable properties, ZnO is one of the novel antibacterial active materials. Nowadays, researchers are making a serious effort to improve the antibacterial activities of ZnO by forming a composite with the same/different bandgap semiconductor materials and doping of ions. Applying capping agents such as polymers and plant extract that control the morphology and size of the nanomaterials and optimizing different conditions also enhance the antibacterial activity. Forming a nanocomposite and doping reduces the electron/hole recombination, increases the surface area to volume ratio, and also improves the stability towards dissolution and corrosion. The release of antimicrobial ions, electrostatic interaction, reactive oxygen species (ROS) generations are the crucial antibacterial activity mechanism. This review also presents a detailed discussion of the antibacterial activity improvement of ZnO by forming a composite, doping, and optimizing different conditions. The morphological analysis using scanning electron microscopy, field emission-scanning electron microscopy, field-emission transmission electron microscopy, fluorescence microscopy, and confocal microscopy can confirm the antibacterial activity and also supports for developing a satisfactory mechanism. Graphical abstract Graphical abstract showing the metal oxides antibacterial mechanism and the fluorescence and scanning electron microscopic images.


2018 ◽  
Vol 243 ◽  
pp. 00017 ◽  
Author(s):  
Daria Goncharova ◽  
Ekaterina Gavrilenko ◽  
Anna Nemoykina ◽  
Valery Svetlichnyi

The paper studies physicochemical and antibacterial properties of ZnO nanoparticles obtained by pulsed laser ablation in water and air. Their composition and structure were studied by X-ray diffraction, transmission and scanning electron microscopy. Antibacterial activity of the nanoparticles was examined by its affection on Gram-positive Staphylococcus aureus (S.aureus). The dependence of nanoparticles’ physical and chemical antibacterial properties on the conditions of the ablation was shown. The model materials for the antibacterial bandage were made of cotton, filter paper and biodegradable polymer scaffolds (poly-l-lactide acid), and then they were coated with the obtained ZnO nanoparticles. The model bandage materials were examined by the scanning electron microscopy method and their antibacterial activity (ISO 20743:2013) was determined. High activity of all the samples against S.aureus was proved.


1994 ◽  
Vol 6 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Marek R. Lipinski ◽  
M. Deon Durholtz

It appears that squid statoliths cannot yet be regarded as accurate an ageing tool as fish otoliths. Statoliths from the same pair, prepared differently for viewing and counting increments, were compared. Increment counts do not imply age in days, because this was not validated. One statolith from each pair was examined by light microscopy (LM) after preparation following a new method. The other was viewed by Scanning Electron microscopy (SEM) with a modified etching solution. Shape of each statolith was similar when compared by multiple regression analysis (11 variables, n=53). There was a weak but significant difference between sexes (statoliths of females were slightly larger). All other differences were insignificant. Microscopic observation and increment counts of increments were successfully carried out for 37 pairs of statoliths. Significant differences between two independent counts were found for the LM method, but no significant differences were found between two independent SEM counts. Counts were significantly different when interpreted by both LM and SEM, probably because of poor resolution in the LM readings and over-resolution (growth layers prominent and numerous) in those read by SEM. Recommendations are made on how ageing studies, based on statoliths, should be structured and the results evaluated.


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