scholarly journals Effects of Composites Containing Bioactive Glasses on Demineralized Dentin

2017 ◽  
Vol 96 (9) ◽  
pp. 999-1005 ◽  
Author(s):  
A. Tezvergil-Mutluay ◽  
R. Seseogullari-Dirihan ◽  
V.P. Feitosa ◽  
G. Cama ◽  
D.S. Brauer ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Direct Contact ◽  
Artificial Saliva ◽  
Dry Mass ◽  
Sem Analysis ◽  
Dental Composites ◽  
Bioactive Glasses ◽  
Beneficial Effects ◽  
Before And After ◽  
Demineralized Dentin

The aim of this study was to evaluate the degradation of completely demineralized dentin specimens in contact with a filler-free or 2 ion-releasing resins containing micrometer-sized particles of Bioglass 45S5 (BAG) or fluoride-containing phosphate-rich bioactive glass (BAG-F). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were also used to evaluate the remineralization induced by the experimental ion-releasing resin-based materials. Dentin beams were totally demineralized in H3PO4 (10%) and placed in direct contact with a filler-free (RESIN) or 2 experimental ion-releasing resins (BAG or BAG-F) and immersed in artificial saliva (AS) up to 30 d. Further specimens were also processed and submitted to FTIR and SEM analysis to evaluate the remineralization induced by such ion-releasing resins before and after AS immersion. BAG and BAG-F alkalinized the incubation media. A significant decrease of the dry mass was observed between the specimens of all groups stored for 3 and 30 d in AS. However, the fluoride-containing phosphate-rich bioactive glass incorporated into a resin-based material (BAG-F) showed greater ability in reducing the solubilization of C-terminal cross-linked telopeptide (ICTP) and C-terminal telopeptide (CTX) after prolonged AS storage. Moreover, after 30 d of AS storage, BAG-F showed the greatest remineralizing effect on the stiffness of the completely demineralized dentin matrices. In conclusion, fluoride-containing phosphate-rich bioactive glass incorporated as micrometer-sized filler in dental composites may offer greater beneficial effects than Bioglass 45S5 in reducing the enzyme-mediated degradation and remineralization of demineralized dentin.

scholarly journals A Chemical Approach to Optimizing Bioactive Glass Dental Composites

2018 ◽  
Vol 98 (2) ◽  
pp. 194-199 ◽  
Author(s):  
S. Aponso ◽  
J.G. Ummadi ◽  
H. Davis ◽  
J. Ferracane ◽  
D. Koley
Keyword(s):  
Bioactive Glass ◽  
Metal Ion ◽  
Volume Fraction ◽  
Dimensional Space ◽  
Resin Composite ◽  
Artificial Saliva ◽  
Basal Medium ◽  
Dental Composites ◽  
Biofilm Growth ◽  
Chemical Microenvironment

The chemical microenvironment surrounding dental composites plays a crucial role in controlling the bacteria grown on these specialized surfaces. In this study, we report a scanning electrochemical microscopy (SECM)–based analytic technique to design and optimize metal ion-releasing bioactive glass (BAG) composites, which showed a significant reduction in biofilm growth. SECM allows positioning of the probe without touching the substrate while mapping the chemical parameters in 3-dimensional space above the substrate. Using SECM and a solid-state H+ and Ca2+ ion-selective microprobe, we determined that the local Ca2+ concentration released by different composites was 10 to 224 µM for a BAG particle size of <5 to 150 µm in the presence of artificial saliva at pH 4.5. The local pH was constant above the composites in the same saliva solution. The released amount of Ca2+ was determined to be maximal for particles <38 µm and a BAG volume fraction of 0.32. This optimized BAG-resin composite also showed significant inhibition of biofilm growth (24 ± 5 µm) in comparison with resin-only composites (53 ± 6 µm) after Streptococcus mutans bacteria were grown for 3 d in a basal medium mucin solution. Biofilm morphology and its subsequent volume, as determined by the SECM imaging technique, was (0.59 ± 0.38) × 107 µm3 for BAG-resin composites and (1.29 ± 0.53) × 107 µm3 for resin-only composites. This study thus lays the foundation for a new analytic technique for designing dental composites that are based on the chemical microenvironment created by biomaterials to which bacteria have been exposed.

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.

scholarly journals Effects of erosive challenge on the morphology and surface properties of luting cements

2016 ◽  
Vol 45 (2) ◽  
pp. 103-109
Author(s):  
Brenna Louise Cavalcanti GONDIM ◽  
Isabella Cavalcante MEDEIROS ◽  
Bruna Palmeira COSTA ◽  
Hugo Lemes CARLO ◽  
Rogério Lacerda dos SANTOS ◽  
...  
Keyword(s):  
Surface Properties ◽  
Zinc Phosphate ◽  
Artificial Saliva ◽  
Sem Analysis ◽  
Resin Matrix ◽  
Luting Cements ◽  
Porous Surfaces ◽  
Before And After ◽  
And Control ◽  
Scanning Electron

Abstract Introduction Few studies investigated the surface properties of luting cements after erosive challenge. Objective To evaluate the surface roughness (Ra), Vickers hardness (VHN) and morphology of 4 luting cements after erosive challenge. Material and method Twenty specimens of each cement were prepared (4×2mm) and divided into experimental (erosive challenge) and control (artificial saliva) groups (n=10): Rely X U200 (U200); Rely X ARC (ARC); Ketac Cem Easy Mix (Ketac) and Zinc phosphate (ZnP). The erosive challenge was performed by four daily erosive cycles (90s) in a cola drink and 2 h in artificial saliva over 7 days. Ra and VHN readings were performed before and after erosion. The percentage of hardness loss (%VHN) was obtained after erosion. The surface morphology was analyzed by scanning electron microscopy (SEM). ANOVA, Tukey and Student-T tests were used (α=0.05). Result After erosion, all luting cements had increase in Ra values and U200 and ZnP groups had the highest %VHN. After saliva immersion, only U200 and ZnP groups had significant increases in Ra values and there were no significant differences among the groups in %VHN. SEM analysis showed that Ketac and ZnP groups had rough and porous surfaces, and U200 group had higher resin matrix degradation than ARC group. Conclusion Erosive challenge with a cola drink affected the surface properties of all luting cements.

scholarly journals Evaluation of Surface Characteristics and Cytotoxicity of Dental Composites

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 749
Author(s):  
Antarinia Crăciun ◽  
Ioana Bȃldea ◽  
Ana Ispas ◽  
Mîndra Eugenia Badea ◽  
Ioan Petean ◽  
...  
Keyword(s):  
Artificial Saliva ◽  
Polarized Light ◽  
Surface Characteristics ◽  
In Vitro Cytotoxicity ◽  
Dental Composites ◽  
Oral Keratinocytes ◽  
Luting Cements ◽  
Before And After ◽  
Dual Curing

The purpose of this study was to evaluate the surface and in vitro cytotoxicity on human dysplastic oral keratinocytes (DOK) of four commercial resins-based dental composites commonly used in prosthodontics dental therapies: two indirect composites for crown and bridges—SR Adoro (IvoclarVivadent GmbH) and Solidex (Shofu Dental GmbH); and two dual-curing luting resin cements—RelyxUnicem (3M ESPE Dental Products) and Variolink Esthetic DC (IvoclarVivadentGmbH). A complex assessment of surface characteristics of the four materials was conducted before and after the exposure to artificial saliva through various analyses, such as Scanning Electron Microscopy, Atomic Force Microscopy and Cross Polarized Light Microscopy (PLM). The results showed that DOK viability was not severely affected by exposure to any of these materials; however, Variolink expressed higher values but still above the toxicity level of the rest of the composites. The analysis of the surface structure between initial and artificial saliva exposed specimens returned a compact aspect in both categories and although Variolink and Relyx were subjected to increased roughness after saliva exposure, no damage of the internal compactness was recorded, demonstrating a fair behavior of the luting cements in contact with the saliva.

scholarly journals Effect of Novel Bioactive Glass-Containing Dentin Adhesive on the Permeability of Demineralized Dentin

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5423
Author(s):  
Hyun-Jung Kim ◽  
Ji-Hyun Jang ◽  
Sang Uk Woo ◽  
Kyoung-Kyu Choi ◽  
Sun-Young Kim ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Sol Gel ◽  
Sem Analysis ◽  
Mode Analysis ◽  
The Novel ◽  
Dentin Adhesives ◽  
Sol Gel Process ◽  
Dentinal Fluid Flow ◽  
Demineralized Dentin ◽  
Dentin Adhesive

This study aimed to evaluate the effect of a novel bioactive glass (BAG)-containing dentin adhesive on the permeability of demineralized dentin. Bioactive glass (85% SiO2, 15% CaO) was fabricated using the sol-gel process, and two experimental dentin adhesives were prepared with 3 wt% silica (silica-containing dentin adhesive; SCA) or BAG (BAG-containing dentin adhesive; BCA). Micro-tensile bond strength (μTBS) test, fracture mode analysis, field-emission scanning electron microscopy (FE-SEM) analysis of adhesive and demineralized dentin, real-time dentinal fluid flow (DFF) rate measurement, and Raman confocal microscopy were performed to compare SCA and BCA. There was no difference in μTBS between the SCA and BCA (p > 0.05). Multiple precipitates were evident on the surface of the BCA, and partial occlusion of dentinal tubules was observed in FE-SEM of BCA-approximated dentin. The DFF rate was reduced by 50.10% after BCA approximation and increased by 6.54% after SCA approximation. Raman confocal spectroscopy revealed an increased intensity of the hydroxyapatite (HA) peak on the dentin surface after BCA application. The novel BAG-containing dentin adhesive showed the potential of both reducing dentin permeability and dentin remineralization.

scholarly journals Surface analysis of latex and silicone pacifier nipples after exposure to acidic artificial saliva: a pilot study

2021 ◽  
Vol 10 (16) ◽  
pp. e111101623074
Author(s):  
Thiago Isidro Vieira ◽  
Kira Maria de Sousa Andrade ◽  
Thayana Maria Navarro Ribeiro de Lima ◽  
Mariana Leonel Martins ◽  
Simone Alves de Sousa ◽  
...  
Keyword(s):  
Pilot Study ◽  
Direct Contact ◽  
Artificial Saliva ◽  
Three Dimensional ◽  
Optical Profilometry ◽  
Roughness Parameters ◽  
Before And After ◽  
Paired T Test ◽  
Qualitative Changes ◽  
Surface Changes

Objective: To measure surface changes of pacifier nipples after immersion in acidic artificial saliva. Methods: Two types of pacifier nipples (latex and silicone) were selected. Five copies of each type were used. The protocol consisted of immersion in acidic artificial saliva (pH = 5.97) for 16 days. The nipples of the pacifier remained in direct contact with saliva in an individualized, opaque and closed container in a bacteriological incubator at 37ºC. The samples were examined before and after exposure to saliva through qualitative (based on images obtained in a 100 mm macro lens and three-dimensional images with 10% amplification obtained in the profilometry) and quantitative (roughness data obtained in non-contact 3D optical profilometry). Data were obtained in duplicate and analyzed using descriptive and inferential statistics. The findings were tested for normality (Shapiro-Wilk). Paired t-test or Wilcoxon was used to compare before and after roughness data. Results: In the image analysis, it was observed that only the surface of the latex pacifier's nipples showed an irregular appearance after exposure to saliva. In the quantitative evaluation, no differences were found between the roughness values before and after (p>0.05). Conclusion: This pilot study demonstrated qualitative changes in the surface of latex pacifiers. However, it was not able to demonstrate statistically significant differences for the roughness parameters before and after exposure to acidic artificial saliva in the nipples of latex and silicone pacifiers.

scholarly journals Beneficial Effects of Akkermansia muciniphila Are Not Associated with Major Changes in the Circulating Endocannabinoidome but Linked to Higher Mono-Palmitoyl-Glycerol Levels as New PPARα Agonists

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 185
Author(s):  
Clara Depommier ◽  
Rosa Maria Vitale ◽  
Fabio Arturo Iannotti ◽  
Cristoforo Silvestri ◽  
Nicolas Flamand ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Univariate Analysis ◽  
Metabolic Effects ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Akkermansia Muciniphila ◽  
Beneficial Effects ◽  
Daily Ingestion ◽  
Before And After ◽  
Palmitoyl Glycerol

Akkermansia muciniphila is considered as one of the next-generation beneficial bacteria in the context of obesity and associated metabolic disorders. Although a first proof-of-concept of its beneficial effects has been established in the context of metabolic syndrome in humans, mechanisms are not yet fully understood. This study aimed at deciphering whether the bacterium exerts its beneficial properties through the modulation of the endocannabinoidome (eCBome). Circulating levels of 25 endogenous endocannabinoid-related lipids were quantified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) in the plasma of overweight or obese individuals before and after a 3 months intervention consisting of the daily ingestion of either alive or pasteurized A. muciniphila. Results from multivariate analyses suggested that the beneficial effects of A. muciniphila were not linked to an overall modification of the eCBome. However, subsequent univariate analysis showed that the decrease in 1-Palmitoyl-glycerol (1-PG) and 2-Palmitoyl-glycerol (2-PG), two eCBome lipids, observed in the placebo group was significantly counteracted by the alive bacterium, and to a lower extent by the pasteurized form. We also discovered that 1- and 2-PG are endogenous activators of peroxisome proliferator-activated receptor alpha (PPARα). We hypothesize that PPARα activation by mono-palmitoyl-glycerols may underlie part of the beneficial metabolic effects induced by A. muciniphila in human metabolic syndrome.

scholarly journals Reduction in mobility and COVID-19 transmission

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pierre Nouvellet ◽  
Sangeeta Bhatia ◽  
Anne Cori ◽  
Kylie E. C. Ainslie ◽  
Marc Baguelin ◽  
...  
Keyword(s):  
Predictive Ability ◽  
Control Measures ◽  
Social Distancing ◽  
Beneficial Effects ◽  
Mobility Data ◽  
Strict Control ◽  
Before And After ◽  
Proxy Measure ◽  
Lower Transmission ◽  
The Relationship

AbstractIn response to the COVID-19 pandemic, countries have sought to control SARS-CoV-2 transmission by restricting population movement through social distancing interventions, thus reducing the number of contacts. Mobility data represent an important proxy measure of social distancing, and here, we characterise the relationship between transmission and mobility for 52 countries around the world. Transmission significantly decreased with the initial reduction in mobility in 73% of the countries analysed, but we found evidence of decoupling of transmission and mobility following the relaxation of strict control measures for 80% of countries. For the majority of countries, mobility explained a substantial proportion of the variation in transmissibility (median adjusted R-squared: 48%, interquartile range - IQR - across countries [27–77%]). Where a change in the relationship occurred, predictive ability decreased after the relaxation; from a median adjusted R-squared of 74% (IQR across countries [49–91%]) pre-relaxation, to a median adjusted R-squared of 30% (IQR across countries [12–48%]) post-relaxation. In countries with a clear relationship between mobility and transmission both before and after strict control measures were relaxed, mobility was associated with lower transmission rates after control measures were relaxed indicating that the beneficial effects of ongoing social distancing behaviours were substantial.

scholarly journals Integration of Dental Implants in Conjunction with EDTA-Conditioned Dentin Grafts: An Experimental Study

2021 ◽  
Vol 9 (6) ◽  
pp. 63
Author(s):  
Payam Farzad ◽  
Ted Lundgren ◽  
Adel Al-Asfour ◽  
Lars Andersson ◽  
Christer Dahlin
Keyword(s):  
Direct Contact ◽  
Mineral Content ◽  
X Rays ◽  
X Ray ◽  
Dentin Surface ◽  
Significant Difference ◽  
C And N ◽  
Micro Implants ◽  
Demineralized Dentin

This study was undertaken to investigate the integration of titanium micro-implants installed in conjunction with previously dentin-grafted areas and to study the morphological appearance, mineral content, and healing pattern of xenogenic EDTA-conditioned dentin blocks and granules grafted to cavities in the tibial bone of rabbits. Demineralized and non-demineralized dentin blocks and granules from human premolars were implanted into cavities prepared on the lateral aspects of the tibias of rabbits. After a healing period of six months, micro-implants were installed at each surgical site. Histological examinations were carried out after 24 weeks. Characterization of the EDTA-conditioned dentin blocks was performed by means of light microscopy, dental X-rays, scanning electron microscopy, and energy dispersive X-ray analysis (EDX). No implants were found to be integrated in direct contact with the dentin particles or blocks. On the EDTA-conditioned dentin surface, the organic marker elements C and N dominated, as revealed by EDX. The hydroxyapatite constituents Ca and P were almost absent on the dentin surface. No statistically significant difference was observed between the EDTA-conditioned and non-demineralized dentin, as revealed by BIC and BA. The bone-inductive capacity of the dentin material seemed limited, although demineralization by means of EDTA indicated higher BIC and BA values in conjunction with the installed implants in the area. A 12 h EDTA treatment did not fully decalcify the grafts, as revealed by X-ray analysis.

scholarly journals Brain Training and Sulforaphane Intake Interventions Separately Improve Cognitive Performance in Healthy Older Adults, Whereas a Combination of These Interventions Does Not Have More Beneficial Effects: Evidence from a Randomized Controlled Trial

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 352
Author(s):  
Rui Nouchi ◽  
Qingqiang Hu ◽  
Toshiki Saito ◽  
Natasha Yuriko dos Santos Kawata ◽  
Haruka Nouchi ◽  
...  
Keyword(s):  
Older Adults ◽  
Active Control ◽  
Processing Speed ◽  
Cognitive Functions ◽  
Controlled Trial ◽  
Memory Performance ◽  
Brain Training ◽  
Beneficial Effects ◽  
Before And After ◽  
Double Blinded

Background: Earlier studies have demonstrated that a single-domain intervention, such as a brain-training (BT) game alone and a sulforaphane (SFN) intake, positively affects cognition. This study examined whether a combined BT and SFN intake intervention has beneficial effects on cognitive function in older adults. Methods: In a 12-week double-blinded randomized control trial, 144 older adults were randomly assigned to one of four groups: BT with SFN (BT-S), BT with placebo (BT-P), active control game (AT) with SFN (AT-S), and active control game with placebo (AT-P). We used Brain Age in BT and Tetris in AT. Participants were asked to play BT or AT for 15 min a day for 12 weeks while taking a supplement (SFN or placebo). We measured several cognitive functions before and after the intervention period. Results: The BT (BT-S and BT-P) groups showed more improvement in processing speed than the active control groups (AT-S and AT-P). The SFN intake (BT-S and AT-S) groups recorded significant improvements in processing speed and working memory performance unlike the placebo intake groups (BT-P and AT-P). However, we did not find any evidence of the combined intervention’s beneficial effects on cognition. Discussion: We discussed a mechanism to improve cognitive functions in the BT and SFN alone interventions.

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