scholarly journals Impact of Warm Vertical Compaction on the Sealing Ability of Calcium Silicate-Based Sealers: A Confocal Microscopic Evaluation

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 372
Author(s):  
Diana Eid ◽  
Etienne Medioni ◽  
Gustavo De-Deus ◽  
Issam Khalil ◽  
Alfred Naaman ◽  
...  

The aim of this in vitro study was to evaluate the dentinal tubule penetration of two calcium silicate-based sealers used in warm vertical compaction (WVC) obturation technique in comparison with the single cone (SC) technique by confocal laser scanning microscopy (CLSM). The null hypothesis was that both obturation techniques produced similar sealer penetration depths at 1 and 5 mm from the apex. Forty-four mandibular single-rooted premolars were randomly divided into four equally experimental groups (n = 10) and two control groups (n = 2) according to the type of sealer (Bio-C Angelus, Londrína, PR, Brazil or HiFlow Brasseler, Savannah, GA, USA) with either SC or WVC. The sealers were mixed with a fluorescent dye Rhodamine B (0.1%) to enable the assessment under the CLSM. All the specimens were sectioned horizontally at 1 and 5 mm from the apex. The maximum penetration depth was calculated using the ImageJ Software (ImageJ, NIH). Data were analyzed by Mann–Whitney U and Kruskal–Wallis tests (p < 0.05). A significant difference was shown between the four groups at 1 mm (p = 0.0116), whereas similar results were observed at 5 mm (p = 0.20). WVC allowed better diffusion for both sealers at 1 mm (p = 0.01) and 5 mm (p = 0.034). The maximum penetration of the Bio-C and HiFlow sealers was more important at 5 mm with the two obturation techniques. Within the limitations of this study, WVC enhanced the penetration of calcium silicate-based sealers into the dentinal tubules in comparison with the SC technique at both levels.

2018 ◽  
Vol 20 (4) ◽  
pp. 238
Author(s):  
Júlia Bazaga Ferreira ◽  
Gabriella Rodovalho Paiva ◽  
Vinícius Rangel Geraldo-Martins ◽  
Juliana Jendiroba Faraoni ◽  
Regina Guenka Palma Dibb ◽  
...  

O objetivo deste trabalho in vitro foi avaliar a influência de diferentes agentes remineralizantes no tratamento de lesões erosivas em esmalte. Foram confeccionados espécimes de 4mmx4mm e 3 mm de espessura a partir da superfície vestibular de incisivos bovinos (n=10) e divididos aleatoriamente em 4 grupos. G1=aplicação do dentifrício remineralizante, G2= aplicação do agente potencializador remineralizante, G3= dentifrício remineralizante + agente potencializador remineralizante, G4=aplicação de verniz fluoretado (controle positivo), G5=nenhum tratamento (controle negativo). Os espécimes foram imersos em refrigerante durante um período de 10 dias. A rugosidade superficial foi analisada por meio de microscopia confocal de varredura a laser. Os dados foram analisados quanto à homogeneidade (Levene’s) e normalidade (Kolmogorov- Smirnov). Foram realizados testes paramétricos com análise de variância a dois critérios: fator tempo e fator tratamento, e pós-teste de Tukey para diferenciação das médias. Todos os testes estatísticos tiveram nível de significância de 5% (α=0,05). Os resultados obtidos mostraram diferenças estatisticamente significantes, demonstrando a redução da rugosidade da superfície do esmalte logo após o primeiro tratamento (G3) e para os demais grupos (G1, G2 e G4) somente após o segundo tratamento. Concluiu-se que a utilização de dentifrício composto por silicato de cálcio e fosfato de sódio influenciou na rugosidade do esmalte erodido do dente bovino.Palavras-chave: Dentifrícios. Erosão Dentária. Esmalte Dentário.Abstract The objective of this in vitro study was to evaluate the influence of different remineralizing agents in the treatment of enamel erosive lesions. Specimens of 4mmx4mm and 3mm thickness were made from the buccal surface of bovine incisors (n=10) and randomly divided into 4 groups. G1 = application of the remineralizing dentifrice, G2 = application of the remineralizing agent, G3 = remineralizing dentifrice + remineralizing agente, G4 = application of fluoride varnish (positive control), G5 = no treatment Specimens were immersed in refrigerant solution during a period of 10 days. The surface roughness was analyzed by means of confocal laser scanning microscopy. The data were analyzed for homogeneity (Levene's) and normality (Kolmogorov-Smirnov). Parametric tests with analysis of variance were performed on two criteria: time factor and treatment factor, and Tukey post-test for differentiation of means. All tests were statistically significant at 5% (α = 0.05). The results showed statistically significant difference, demonstrating the reduction of surface roughness after the first treatment (G3) and the other groups (G1, G2 and G4) only after the second treatment. It was concluded that the use of dentifrice composed of calcium silicate and sodium phosphate influenced the roughness of the eroded tooth enamel of the bovine tooth.Keywords: Dentifrices. Tooth Erosion. Tooth Enamel.


Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2473
Author(s):  
Xiu Peng ◽  
Sili Han ◽  
Kun Wang ◽  
Longjiang Ding ◽  
Zhenqi Liu ◽  
...  

In this study, the amelogenin-derived peptide, TVH-19, which has been confirmed to promote mineralization, was evaluated to derive its potential to induce dentinal tubule occlusion. The binding capability of fluorescein isothiocyanate (FITC)-labeled TVH-19 to the demineralized dentin surface was analyzed by confocal laser scanning microscopy (CLSM). Additionally, the sealing function of the peptide was studied through the remineralization of demineralized dentin in vitro. The adsorption results showed that TVH-19 could bind to the hydroxyapatite and demineralized dentin surfaces, especially to periodontal dentin. Scanning electron microscopy analysis further revealed that TVH-19 created mineral precipitates. The plugging rate in the TVH-19 group was higher than that in the PBS group. Moreover, energy-dispersive X-ray spectroscopy (EDX) results indicated that the calcium/phosphorus (Ca/P) ratio of the new minerals induced by TVH-19 was close to that of the hydroxyapatite. Attenuated total internal reflection-Fourier transform infrared (ATR-FTIR) spectrometry and X-ray diffraction (XRD) results indicated that the hydroxyapatite crystals formed via remineralization elongated the axial growth and closely resembled the natural dentin components. These findings indicate that TVH-19 can effectively promote dentin sealing by binding to the periodontal dentin, promoting mineral deposition, and reducing the space between the dentin tubules.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1809
Author(s):  
Jifen Zhang ◽  
Yanhua Wang ◽  
Jirui Wang ◽  
Tao Yi

A drug nanocrystals self-stabilized Pickering emulsion (NSSPE) with a unique composition and microstructure has been proven to significantly increase the bioavailability of poorly soluble drugs. This study aimed to develop a new solid NSSPE of puerarin preserving the original microstructure of NSSPE by spray-drying. A series of water-soluble solid carriers were compared and then Box-Behnken design was used to optimize the parameters of spray-drying. The drug release and stability of the optimized solid NSSPE in vitro were also investigated. The results showed that hydroxypropyl-β-cyclodextrin (HP-β-CD), rather than solid carriers commonly used in solidification of traditional Pickering emulsions, was suitable for the solid NSSPE to retain the original appearance and size of emulsion droplets after reconstitution. The amount of HP-β-CD had more influences on the solid NSSPE than the feed rate and the inlet air temperature. Fluorescence microscopy, confocal laser scanning microscopy and scanning electron microscopy showed that the reconstituted emulsion of the solid NSSPE prepared with HP-β-CD had the same core-shell structure with a core of oil and a shell of puerarin nanocrystals as the liquid NSSPE. The particle size of puerarin nanocrystal sand interfacial adsorption rate also did not change significantly. The cumulative amount of released puerarin from the solid NSSPE had no significant difference compared with the liquid NSSPE, which were both significantly higher than that of puerarin crude material. The solid NSSPE was stable for 3 months under the accelerated condition of 75% relative humidity and 40 °C. Thus, it is possible todevelop the solid NSSPE preserving the unique microstructure and the superior properties in vitro of the liquid NSSPE for poorly soluble drugs.


2020 ◽  
Vol 8 (D) ◽  
pp. 218-223
Author(s):  
Abraham Sathish ◽  
Karad Rohini Ramesh ◽  
N. Jain Ruchika ◽  
D. Vaswani Sneha ◽  
B. Najan Harshal ◽  
...  

AIM: The study aimed to investigate the penetration depth of calcium hydroxide-based root canal sealer into buccolingual and mesiodistal aspects of roots with and without the butterfly effect at coronal and middle root sections. METHODS AND MATERIALS: Twenty single-rooted maxillary premolars were decoronated at the cementoenamel junction and viewed under a light microscope and grouped as Group 1 – butterfly (B) and Group 2 – non-butterfly according to the presence or absence of the effect. Canals were prepared till working length followed with copious irrigation. Canals were finally rinsed with 5 ml of 17% ethylenediaminetetraacetic acid solution and activated using EndoActivator followed by obturation using gutta-percha (warm vertical compaction technique) with Sealapex sealer. To provide fluorescence for confocal laser scanning microscopy (CLSM), the Sealapex was mixed with rhodamine B dye. Root sectioning yielded coronal and middle sections. CLSM was used to assess the penetration of the sealer. STATISTICAL ANALYSIS: Shapiro–Wilk test, unpaired “t-test.” RESULTS: Teeth with the butterfly effect had greater mean penetration buccolingually (905.2 μm) than mesiodistally (182.1 μm; p < 0.001). Coronal sections had greater penetration (517.4 μm) compared with the middle (354.6 μm). CONCLUSION: Sealapex sealer exhibited maximum tubular penetration in teeth with butterfly effect in buccolingual direction at the coronal third level.


Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.


TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.


2019 ◽  
Vol 5 (1) ◽  
pp. 85-97
Author(s):  
Nusrat Sharmin ◽  
Mohammad S. Hasan ◽  
Md. Towhidul Islam ◽  
Chengheng Pang ◽  
Fu Gu ◽  
...  

AbstractPresent work explores the relationship between the composition, dissolution rate, ion release and cytocompatibility of a series of borophosphate glasses. While, the base glass was selected to be 40mol%P2O5-16mol%CaO-24mol%MgO-20mol%Na2O, three B2O3 modified glass compositions were formulated by replacing Na2O with 1, 5 and 10 mol% B2O3. Ion release study was conducted using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The thermal scans of the glasses as determined by differential scanning calorimetry (DSC) revealed an increment in the thermal properties with increasing B2O3 content in the glasses. On the other hand, the dissolution rate of the glasses decreased with increasing B2O3 content. To identify the effect of boron ion release on the cytocompatibility properties of the glasses, MG63 cells were cultured on the surface of the glass discs. The in vitro cell culture study suggested that glasses with 5 mol% B2O3 (P40B5) showed better cell proliferation and metabolic activity as compares to the glasses with 10 mol% (P40B10) or with no B2O3 (P40B0). The confocal laser scanning microscopy (CLSM) images of live/dead stained MG63 cells attached to the surface of the glasses also revealed that the number of dead cells attached to P40B5 glasses were significantly lower than both P40B0 and P40B10 glasses.


2019 ◽  
Vol 75 (1) ◽  
pp. 117-125 ◽  
Author(s):  
Odel Soren ◽  
Ardeshir Rineh ◽  
Diogo G Silva ◽  
Yuming Cai ◽  
Robert P Howlin ◽  
...  

Abstract Objectives The cephalosporin nitric oxide (NO)-donor prodrug DEA-C3D (‘DiEthylAmin-Cephalosporin-3′-Diazeniumdiolate’) has been shown to initiate the dispersal of biofilms formed by the Pseudomonas aeruginosa laboratory strain PAO1. In this study, we investigated whether DEA-C3D disperses biofilms formed by clinical cystic fibrosis (CF) isolates of P. aeruginosa and its effect in combination with two antipseudomonal antibiotics, tobramycin and colistin, in vitro. Methods β-Lactamase-triggered release of NO from DEA-C3D was confirmed using a gas-phase chemiluminescence detector. MICs for P. aeruginosa clinical isolates were determined using the broth microdilution method. A crystal violet staining technique and confocal laser scanning microscopy were used to evaluate the effects of DEA-C3D on P. aeruginosa biofilms alone and in combination with tobramycin and colistin. Results DEA-C3D was confirmed to selectively release NO in response to contact with bacterial β-lactamase. Despite lacking direct, cephalosporin/β-lactam-based antibacterial activity, DEA-C3D was able to disperse biofilms formed by three P. aeruginosa clinical isolates. Confocal microscopy revealed that DEA-C3D in combination with tobramycin produces similar reductions in biofilm to DEA-C3D alone, whereas the combination with colistin causes near complete eradication of P. aeruginosa biofilms in vitro. Conclusions DEA-C3D is effective in dispersing biofilms formed by multiple clinical isolates of P. aeruginosa and could hold promise as a new adjunctive therapy to patients with CF.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Beatriz H. D. Panariello ◽  
Justin K. Kindler ◽  
Kenneth J. Spolnik ◽  
Ygal Ehrlich ◽  
George J. Eckert ◽  
...  

AbstractRoot canal disinfection is of utmost importance in the success of the treatment, thus, a novel method for achieving root canal disinfection by electromagnetic waves, creating a synergistic reaction via electric and thermal energy, was created. To study electromagnetic stimulation (EMS) for the disinfection of root canal in vitro, single rooted teeth were instrumented with a 45.05 Wave One Gold reciprocating file. Specimens were sterilized and inoculated with Enterococcus faecalis ATCC 29,212, which grew for 15 days to form an established biofilm. Samples were treated with 6% sodium hypochlorite (NaOCl), 1.5% NaOCl 1.5% NaOCl with EMS, 0.9% saline with EMS or 0.9% saline. After treatments, the colony forming units (CFU) was determined. Data was analyzed by Wilcoxon Rank Sums Test (α = 0.05). One sample per group was scored and split for confocal laser scanning microscopy imaging. There was a significant effect with the use of NaOCl with or without EMS versus 0.9% saline with or without EMS (p = 0.012 and 0.003, respectively). CFUs were lower when using 0.9% saline with EMS versus 0.9% saline alone (p = 0.002). Confocal imaging confirmed CFU findings. EMS with saline has an antibiofilm effect against E. faecalis and can potentially be applied for endodontic disinfection.


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