scholarly journals Dentine Tubule Occlusion by Novel Bioactive Glass-Based Toothpastes

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Luiza Pereira Dias da Cruz ◽  
Robert G. Hill ◽  
Xiaojing Chen ◽  
David G. Gillam
Keyword(s):  
Bioactive Glass ◽  
Artificial Saliva ◽  
Sem Images ◽  
Human Teeth ◽  
Good Surface ◽  
Vitro Model ◽  
Dentine Tubule ◽  
And Control ◽  
Acid Challenge

There are numerous over-the-counter (OTC) and professionally applied (in-office) products and techniques currently available for the treatment of dentine hypersensitivity (DH), but more recently, the use of bioactive glasses in toothpaste formulations have been advocated as a possible solution to managing DH. Aim. The aim of the present study, therefore, was to compare several bioactive glass formulations to investigate their effectiveness in an established in vitro model. Materials and Methods. A 45S5 glass was synthesized in the laboratory together with several other glass formulations: (1) a mixed glass (fluoride and chloride), (2) BioMinF, (3) a chloride glass, and (4) an amorphous chloride glass. The glass powders were formulated into five different toothpaste formulations. Dentine discs were sectioned from extracted human teeth and prepared for the investigation by removing the cutting debris (smear layer) following sectioning using a 6% citric acid solution for 2 minutes. Each disc was halved to provide test and control halves for comparison following the brushing of the five toothpaste formulations onto the test halves for each toothpaste group. Following the toothpaste application, the test discs were immersed in either artificial saliva or exposed to an acid challenge. Results. The dentine samples were analyzed using scanning electron microscopy (SEM), and observation of the SEM images indicated that there was good surface coverage following artificial saliva immersion. Furthermore, although the acid challenge removed the hydroxyapatite layer on the dentine surface for most of the samples, except for the amorphous chloride glass, there was evidence of tubular occlusion in the dentine tubules. Conclusions. The conclusions from the study would suggest that the inclusion of bioactive glass into a toothpaste formulation may be an effective approach to treat DH.

scholarly journals In vitro study of dentin hypersensitivity treated by whitlockite glass-ceramics

2017 ◽  
Author(s):  
Amanda C. Juraski
Keyword(s):  
Bioactive Glass ◽  
Artificial Saliva ◽  
Third Molar ◽  
Glass Ceramics ◽  
In Vitro Study ◽  
Positive Control ◽  
Negative Control ◽  
Dentin Hypersensitivity ◽  
Human Teeth

AbstractThe aim of this study is to evaluate the potential of a bioactive glass based on the 3CaO.P2O5-SiO2MgO-system and its glassceramics containing whitlockite on the remineralization of dentin as a possible treatment to dentin hypersensitivity. For that, 40 third molar human teeth were artificially demineralized and randomly distributed in 4 groups (n = 10): G1 - Negative Control (no treatment), G2 - Positive Control (treated by Bioglass® 45S5), G3 – BG (treated by bioactive glass based on 3CaO.P2O5-SiO2-MgOsystem), and G4 – BGC (treated by bioactive whitlockite glass-ceramics). After treatment, the samples were emerged in artificial saliva and stored for 7 days in a controlled temperature of 37ºC. After that, scanning electron microscopy (SEM) and atomic force microscopy (AFM) was used to evaluate samples morphology. The analysis confirmed the formation of hydroxyapatite on the surface of all the biomaterials studied, that in the dentine specimens treated by bioactive glass and whitlockite glas-ceramic most of the dentinal tubules were completely occluded.

scholarly journals Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants

2016 ◽  
Vol 21 (5) ◽  
pp. 39-46 ◽  
Author(s):  
Celha Borges Costa Alves ◽  
◽  
Márcio Nunes Segurado ◽  
Miriam Cristina Leandro Dorta ◽  
Fátima Ribeiro Dias ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Statistical Analysis ◽  
Atomic Absorption ◽  
Artificial Saliva ◽  
Atomic Absorption Spectrophotometry ◽  
Sem Images ◽  
Absorption Spectrophotometry ◽  
Mini Implants ◽  
Vanadium Ions

ABSTRACT Objective: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. Methods: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. Results: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. Conclusion: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.

Elevated endothelial microparticle—monocyte complexes induced by multiple sclerosis plasma and the inhibitory effects of interferon-β1b on release of endothelial microparticles, formation and transendothelial migration of monocyte-endothelial microparticle complexes

2005 ◽  
Vol 11 (3) ◽  
pp. 310-315 ◽  
Author(s):  
Joaquin J Jimenez ◽  
Wenche Jy ◽  
Lucia M Mauro ◽  
Lawrence L Horstman ◽  
Eugene R Ahn ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Transendothelial Migration ◽  
Endothelial Microparticles ◽  
Functional Roles ◽  
Monocyte Migration ◽  
Therapeutic Mechanism ◽  
Demyelinating Lesions ◽  
Vitro Model ◽  
And Control

Monocyte migration through the disrupted cerebral endothelial cell (EC) junctions plays an essential role in formation of multiple sclerosis (MS) demyelinating lesions. During pathogenesis of MS, activated ECs release endothelial microparticles (EMP), which possibly facilitate transendothelial migration (TEMIG) of monocytes. To assess functional roles of EMP in MS, specifically, their (i) interaction with monocytes, (ii) effect on monocyte TEMIG in an in vitro model of the brain microvascular endothelial cells (BMVEC), (iii) phenotypic profiles of EMP elicited by MS plasma and (iv) the effects of IFN-b1b on release of EMP and on TEMIG of monocytes (mono) and monocytes:EMP complexes (mono:EMP) through the BMVEC. The effect of IFN-b1b on the release of EMP and the TEMIG of mono and mono:EMP was assessed by preincubating BMVEC cultures of IFN-b1b prior to addition of plasma. Three EMP phenotypes, CD54, CD62E and CD31 were assayed. Plasma specimens from 20 patients with relapsing—remitting MS (11 in exacerbation, MS-E, and 9 in remission, ME-R) and 10 healthy controls were studied. Incubation of BMVEC with MS-E plasma yielded elevated levels of EMPCD54, EMP62E and EMPCD31 relative to MS-R and control plasmas. MS-E but not MS-R or control plasma also augmented TEMIG of monocytes, respectively. Mono:EMP complexes further augmented TEMIG relative to mono alone, but only in the presence of MS-E plasma; there was no significant effect with MS-R or control plasmas. The presence of IFN-b1b inhibited TEMIG of mono and mono:EMP by 20% and 30%, respectively. MS-E but not MS-R plasma elicited release of activation-derived EMP and enhanced TEMIG of mono and mono:EMP. IFN-b1b inhibited TEMIG and release of EMP, suggesting a role of EMP and a novel therapeutic mechanism for IFN-β1b in MS.

In vitro model for frontal sinus obliteration with bioactive glass S53P4

2000 ◽  
Vol 53 (2) ◽  
pp. 161-166 ◽  
Author(s):  
Matti J. Peltola ◽  
Jouko T. K. Suonp�� ◽  
H. Andersson ◽  
Heli S. M��tt�nen ◽  
Kalle M. J. Aitasalo ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Frontal Sinus ◽  
In Vitro Model ◽  
Vitro Model ◽  
Sinus Obliteration

scholarly journals CELLULAR IMMUNITY IN VITRO

1971 ◽  
Vol 133 (6) ◽  
pp. 1377-1389 ◽  
Author(s):  
Harvey B. Simon ◽  
John N. Sheagren
Keyword(s):  
Cellular Immunity ◽  
In Vitro Model ◽  
Specific Antigen ◽  
Cell Types ◽  
Intracellular Bacteria ◽  
Migration Inhibition ◽  
Vitro Model ◽  
And Control ◽  
Macrophage Migration Inhibition

An in vitro model of cellular immunity in the guinea pig was established. Animals were immunized with tubercle bacilli, bovine gamma globulin, or picrylated human serum albumin in complete Freund's adjuvant. Oil-induced peritoneal exudates from immune and control animals were cultured overnight with and without specific antigen. The cultures were washed and the macrophage monolayers were infected with Listeria monocytogenes. At intervals the monolayers were lysed and the numbers of viable intracellular bacteria were quantitated by pour plate cultures. Random monolayers were also evaluated in sequence by visually counting the intracellular bacteria on Gram-stained plates. Both methods demonstrated that the macrophages from immune animals had markedly enhanced listericidal activity when the peritoneal exudates were cultured with antigen before infection. Macrophage migration inhibition was also demonstrated under these conditions. The experiments reported here describe an in vitro model of cellular immunity which will allow separation and recombination of cell types and direct assay of cell products in efforts to elucidate further the mechanisms of the immunologically mediated enhancement of macrophage bactericidal capacity.

scholarly journals Effects of Additional Use of Bioactive Glasses or a Hydroxyapatite Toothpaste on Remineralization of Artificial Lesions in vitro

2020 ◽  
Vol 54 (4) ◽  
pp. 336-342
Author(s):  
Philipp Körner ◽  
Jana A Schleich ◽  
Daniel B. Wiedemeier ◽  
Thomas Attin ◽  
Florian J. Wegehaupt
Keyword(s):  
Bioactive Glass ◽  
Artificial Saliva ◽  
Test Group ◽  
In Vitro Study ◽  
Negative Control Group ◽  
Negative Control ◽  
Control Group ◽  
Bioactive Glasses ◽  
Initial Caries

<b><i>Objectives:</i></b> This in vitro study aimed to evaluate and compare the effect of two different bioactive glasses, a hydroxyapatite-containing, fluoride-free toothpaste (HTP) and a fluoride toothpaste (FTP) on the remineralization behavior of initial caries lesions. <b><i>Materials and Methods:</i></b> A total of 100 bovine enamel samples were randomly allocated to five groups of 20 samples each: NC = negative control group (artificial saliva); HTP = HTP group (Karex); FTP = FTP group (Elmex caries protection, 1,400 ppm); FTP + BG<sub>nano</sub> = FTP followed by Actimins bioactive glass; FTP + BG<sub>amorph</sub> = FTP followed by Schott bioactive glass. Radiographic documentation (advanced transversal microradiography; aTMR) was applied before and after all samples were exposed to a demineralizing gel for 10 days. Over a period of 28 days, samples were covered twice a day (every 12 h) with a toothpaste slurry of the respective test group or with artificial saliva in NC for 60 s and brushed with 15 brushing strokes. Samples in FTP + BG<sub>nano</sub> and FTP + BG<sub>amorph</sub> were additionally treated with the respective bioactive glass slurry for 30 s after brushing with the FTP. In the meantime, all samples were stored in artificial saliva. After 28 days, the structure of all samples was assessed again using aTMR and compared to the values measured after demineralization. The statistical evaluation of the integrated mineral loss was performed using Kruskal-Wallis test followed by a post hoc Conover test. <b><i>Results:</i></b> The FTP revealed the significantly highest increase of mineral content while the HTP showed the significantly lowest remineralization. Compared to artificial saliva, the use of the HTP or the combined application of FTP followed by bioactive glasses (FTP + BG<sub>nano</sub> and FTP + BG<sub>amorph</sub>) showed no significant remineralization. <b><i>Conclusion:</i></b> Under remineralizing in vitro conditions, brushing with 1,400 ppm FTP induced significantly more remineralization compared to storage in artificial saliva. The additional administration of both bioactive glasses as well as the substitutional brushing with an HTP resulted in significantly less remineralization compared to brushing with 1,400 ppm FTP.

PDX validation of a 3D microtumor platform.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 3029-3029
Author(s):  
Ellen Sampson ◽  
Katya Nikolov ◽  
Paul T. Henderson ◽  
Christian Apfel ◽  
Chong-xian Pan ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Tumor Growth ◽  
Saline Control ◽  
Patient Derived Xenograft ◽  
Pdx Model ◽  
End Of Treatment ◽  
Observational Cohort ◽  
Vitro Model ◽  
And Control

3029 Title: Patient-derived xenograft validation of a 3D microtumor platform Background: Patient-derived xenograft (PDX) mouse models are thought to most closely reflect the biology of a patient’s cancer. Unfortunately, growing sufficient tumor in a PDX model takes several months and more often than not, the tumor fails to grows at all. The SAGE Direct Platform, an in-vitro model, can create hundreds of live microtumors from virtually every patient’s viable biopsy and test a panel of clinically relevant drugs within no more than 1 week. Thus, concordance of results from a PDX model with results of the SAGE Direct Platform would support a rational for the platform to be potentially useful to predict tumor response in cancer patients. Methods: A bladder cancer from a 77 year old female was used to establish a PDX model. Mice were divided into three groups receiving either saline (control), cisplatin, or gemcitabine intraperitoneal on the days 1, 8, and 13, and tumor growth was observed. One tumor sample was used to create 3D microtumors and those were tested using the same drugs. Results: Tumor growth (exceeding 1,000 mm3) was similar after cisplatin compared to control (4.8 vs. 3.7 weeks). After gemcitabine tumors initially shrank and only started growing a couple of weeks after the end of treatment so that 1,000 mm3 was only reached after 10.2 weeks (p<0.001 compared to cisplatin and control). In the SAGE Direct Platform the EC50 of cisplatin was 97.3 µM and thus two orders of magnitudes higher than the EC50 of gemcitabine, which was 0.7 µM. Conclusions: Both the PDX model and the SAGE Direct Platform have shown this bladder cancer to be virtually resistant to cisplatin while very sensitive to gemcitabine. The next steps of these preliminary data could be to repeat this experimental design with other tumors and/or to start an observational cohort study in patients correlating the SAGE Direct Platform results to patient outcomes.

Radiotherapy Reduces Microhardness and Mineral and Organic Composition, and Changes the Morphology of Primary Teeth: An in vitro Study

2018 ◽  
Vol 53 (3) ◽  
pp. 296-304 ◽  
Author(s):  
Lenita Marangoni-Lopes ◽  
Gabriela Rovai-Pavan ◽  
Carolina Steiner-Oliveira ◽  
Marinês Nobre-dos-Santos
Keyword(s):  
Primary Teeth ◽  
Morphological Changes ◽  
Artificial Saliva ◽  
Surface Hardness ◽  
In Vitro Study ◽  
Sem Analysis ◽  
Sem Images ◽  
Organic Composition ◽  
Nonnormal Distribution

Objective: We aimed to evaluate whether radiotherapy causes changes in the mineral composition, hardness, and morphology of enamel and dentin of primary teeth. Materials and Methods: Thirty specimens of primary teeth were subjected to radiotherapy. At baseline and after 1,080, 2,160, and 3,060 cGy, the specimens were subjected to microhardness, FT-Raman spectroscopy, and scanning electron microscopy (SEM) analysis. The pH of artificial saliva was determined, as were the calcium and phosphate concentrations. The data were subjected to the Shapiro-Wilk normality test, showed a nonnormal distribution, and were compared by the Kruskal-Wallis test. Results: The results showed that the microhardness of the enamel surface decreased after 2,160 cGy (281.5 ± 58 kgf/mm2) when compared to baseline (323.6 ± 59.5 kgf/mm2) (p = 0.045). For dentin, the surface hardness decreased after 1,080 cGy (34.9 ± 11.4 kgf/mm2) and 2,160 cGy (26 ± 3.5 kgf/mm2) when compared to baseline (56.5 ± 7.7 kgf/mm2) (p < 0.0001). The mineral and organic contents of phosphate (p < 0.0001), carbonate (p < 0.0001), amide (p = 0.0002), and hydrocarbons (p = 0.0031) of enamel decreased after 3,060 cGy (5,178 ± 1,082, 3,868 ± 524, 999 ± 180, and 959 ± 168 kgf/mm2, respectively). For dentin, we noticed a growing increase in phosphate v2, amide, and hydrocarbon content after 1,080 cGy (8,210 ± 2,599, 5,730 ± 1,818, and 6,118 ± 1,807 kgf/mm2, respectively) and 2,160 cGy (1,0071 ± 2,547, 7,746 ± 1,916, and 8,280 ± 2,079 kgf/mm2, respectively) and a reduction after 3,060 cGy (6,782 ± 2,175, 3,558 ± 1,884, and 3,565 ± 1,867 kgf/mm2, respectively) (p < 0.0001). SEM images showed cracks on enamel and degradation of peritubular dentin. Conclusion: We concluded that radiotherapy caused a reduction in surface hardness, changed mineral and organic composition, and promoted morphological changes on the enamel and dentin of primary teeth.

scholarly journals Effects of Axotomy on Cultured Sensory Neurons of Aplysia: Long-Term Injury-Induced Changes in Excitability and Morphology Are Mediated by Different Signaling Pathways

2008 ◽  
Vol 100 (6) ◽  
pp. 3209-3224 ◽  
Author(s):  
Supinder S. Bedi ◽  
Diancai Cai ◽  
David L. Glanzman
Keyword(s):  
Signaling Pathways ◽  
Sensory Neurons ◽  
Specific Inhibitor ◽  
Distinct Pattern ◽  
Extracellular Signal ◽  
Vitro Model ◽  
Induced Changes ◽  
And Control

To facilitate an understanding of injury-induced changes within the nervous system, we used a single-cell, in vitro model of axonal injury. Sensory neurons were individually dissociated from the CNS of Aplysia and placed into cell culture. The major neurite of some neurons was then transected (axotomized neurons). Axotomy in hemolymph-containing culture medium produced long-term hyperexcitability (LTH-E) and enhanced neuritic sprouting (long-term hypermorphogenesis [LTH-M]). Axotomy in the absence of hemolymph induced LTH-E, but not LTH-M. Hemolymph-derived growth factors may activate tyrosine receptor kinase (Trk) receptors in sensory neurons. To examine this possibility, we treated uninjured (control) and axotomized sensory neurons with K252a, an inhibitor of Trk receptor activity. K252a depressed the excitability of both axotomized and control neurons. K252a also produced a distinct pattern of arborizing outgrowth of neurites in both axotomized and control neurons. Protein kinase C (PKC) is an intracellular signal downstream of Trk; accordingly, we tested the effects of bisindolylmaleimide I (Bis-I), a specific inhibitor of PKC, on the axotomy-induced cellular changes. Bis-I blocked LTH-E, but did not disrupt LTH-M. Finally, because Trk activates the extracellular signal regulated kinase pathway in Aplysia sensory neurons, we examined whether this pathway mediates the injury-induced changes. Sensory neurons were axotomized in the presence of U0126, an inhibitor of mitogen-activated/extracellular receptor-regulated kinase. U0126 blocked the LTH-M due to axotomy, but did not impair LTH-E. Therefore distinct cellular signaling pathways mediate the induction of LTH-E and LTH-M in the sensory neurons.

scholarly journals Influence of Zirconia-Coated Bioactive Glass on Gingival Fibroblast Behavior

2019 ◽  
Vol 30 (4) ◽  
pp. 333-341
Author(s):  
Suelen Aline de Lima Barros ◽  
Diana Gabriela Soares ◽  
Maria Luísa Leite ◽  
Fernanda Gonçalves Basso ◽  
Carlos Alberto de Souza Costa ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Free Energy ◽  
Thermal Treatment ◽  
Bioactive Glass ◽  
Gingival Fibroblast ◽  
Sem Images ◽  
Bioactive Coating ◽  
Collagen Expression ◽  
And Migration

Abstract The objective of this study was the development of a bioactive glass coating on zirconia (Zr) to modulate the gingival fibroblast phenotype. For this purpose, Biosilicate® (BS) particles in a water/isopropyl alcohol (1:1) vehicle (6 mg/mL) were applied to zirconia discs followed by thermal treatment at 1100 °C for 20 min. The surface topography (SEM), chemical composition (EDX), surface roughness (Ra; confocal microscopy), surface free energy (goniometry), and color alteration (UV-vis spectrophotometry) were assessed (n=6). Thereafter, L929 fibroblasts were seeded onto Zr and Zr+BS discs, and cell proliferation (Alamar Blue; n=6), morphology (SEM; n=2), migration (wound healing; n=4), and collagen synthesis (Sirius Red; n=6) were evaluated up to 7 days. Data were analyzed by ANOVA/Tukey tests (a=5%). A homogeneous coating consisting of Si, Na, O, and Ca was detected on the Zr surface after thermal treatment with BS, which led to a significant increase in surface roughness and free energy (p<0.05). No change in color parameters was observed (p>0.05). Cells seeded on the Zr+BS surface featured increased proliferation, collagen expression, and migration capability in comparison with those cultured on plain Zr (p<0.05). SEM images revealed that cell spreading occurred faster in the presence of BS. Therefore, it was concluded that thermal treatment of the Zr surface with BS led to the deposition of a bioactive coating, which induced gingival fibroblast spread, proliferation, migration, and collagen expression in vitro.

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