A novel intracranial exchange guidewire improves the navigation of various endovascular devices: An in vitro study of challenging situations

2021 ◽  
pp. 159101992110573
Author(s):  
Naoki Kaneko ◽  
Ariel Takayanagi ◽  
Hamidreza Saber ◽  
Lea Guo ◽  
Satoshi Tateshima

Objective Neuroendovascular procedures rely on successful navigation and stable access to the target vessel. The Stabilizer is a 300 cm long exchange wire with a 0.014 diameter and a soft, flexible stent at the distal end designed to assist with navigation and device delivery. This study aims to assess the efficacy of the Stabilizer for navigation in a variety of challenging environments. Methods The efficacy of the Stabilizer was evaluated using three challenging vascular models: a giant aneurysm model, a severe tortuosity model, and an M1 stenosis model. The Stabilizer was compared with a conventional wire during navigation in each model. Results In the giant aneurysm model, there was no significant difference of success during straightening of a looped wire and significantly higher success rates when advancing an intermediate catheter with the Stabilizer beyond the aneurysm neck compared to a conventional guidewire. The Stabilizer also significantly increased success rates when advancing an intermediate catheter through a model with severe tortuosity compared to a conventional guidewire, as well as exchange maneuver for intracranial stenting in a stenosis model compared to an exchange wire. Conclusions In our experimental model, the Stabilizer significantly improved navigation and device delivery in a variety of challenging settings compared to conventional wires.

Author(s):  
Rathika Rai ◽  
M. A. Easwaran ◽  
K. T. Dhivya

Aim: To evaluate the surface detail reproduction of dental stone this is immersed in different disinfectant solution and studied under stereomicroscope. Methodology: Total number of 30 specimens of dental stone (Type III) were made with measurements of 1.5cm diameter and 1cm height .This samples are divided in to 3 groups group A,B,C. were A is immersed in Distilled water which was taken as control group ;B is immersed in 2% Glutaraldehyde and C is immersed in 5%sodium hypochlorite. Each specimen were immersed in the disinfectant solution for 15 minutes and dried under room temperature for 24 hrs. After 24 hrs each specimens are studied under stereomicroscope for surface details. Result: The results showed no significant difference in the surface irregularities and porosities for a group 1 and group 2 except group 3 which showed significant increase in the porosities, surface irregularities and erosions after disinfection with 5% NaHOCl by immersion method. Conclusion: The surface detail reproduction capacity of die stone was adversely affected when 5% Sodium hypochlorite was used as disinfectant solution when compare d to control group and 2% Glutaraldehyde


2021 ◽  
Vol 11 (2) ◽  
pp. 857
Author(s):  
Keunbada Son ◽  
Kyu-Bok Lee

The purpose of this in vitro study was to evaluate marginal and internal fits of ceramic crowns fabricated with chairside computer-aided design and manufacturing (CAD/CAM) systems. An experimental model based on ISO 12836:2015 was digitally scanned with different intraoral scanners (Omnicam (CEREC), EZIS PO (DDS), and CS3500 (Carestream)). Ceramic crowns were fabricated using the CAD/CAM process recommended by each system (CEREC, EZIS, and Carestream systems; N = 15). The 3-dimensional (3D) marginal and internal fit of each ceramic crown was measured using a 3D inspection software (Geomagic control X). Differences among the systems and various measurements were evaluated using the Kruskal–Wallis test. Statistically significant differences were validated using pairwise comparisons (α = 0.05). Occlusal gaps in the CEREC, EZIS, and Carestream groups were 113.0, 161.3, and 438.2 µm, respectively (p < 0.001). The axial gaps were 83.4, 78.0, and 107.9 µm, respectively. The marginal gaps were 77.8, 99.3, and 60.6 µm, respectively, and the whole gaps were 85.9, 107.3, and 214.0 µm, respectively. Significant differences were observed with the EZIS system compared with the other two systems in terms of the marginal gap sizes. The CEREC system showed no significant differences among the four measured regions. However, the EZIS and Carestream systems did show a statistically significant difference (p < 0.05). All three systems were judged to be capable of fabricating clinically acceptable prostheses, because the marginal gap, which is the most important factor in the marginal fit of prostheses, was recorded to be below 100 µm in all three systems.


2021 ◽  
pp. 088532822110195
Author(s):  
Moataz Elsisy ◽  
Mahdis Shayan ◽  
Yanfei Chen ◽  
Bryan W Tillman ◽  
Catherine Go ◽  
...  

Nitinol is an excellent candidate material for developing various self-expanding endovascular devices due to its unique properties such as superelasticity, biocompatibility and shape memory effect. A low-energy laser joining technique suggests a high potential to create various large diameter Nitinol endovascular devices that contain complex geometries. The primary purpose of the study is to investigate the effects of laser joining process parameters with regard to the mechanical and biocompatible performance of Nitinol stents. Both the chemical composition and the microstructure of the laser-welded joints were evaluated using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). In vitro study results on cytotoxicity demonstrated that the joining condition of 8 Hz frequency and 1 kW laser power showed the highest degree of endothelial cell viability after thermal annealing in 500°C for 30 min. Also, in vitro study results showed the highest oxygen content at 0.9 kW laser power, 8 Hz frequency, and 0.3 mm spot size after the thermal annealing. Mechanical performance test results showed that the optimal condition for the highest disconnecting force was found at 1 Hz frequency and 1 kW power with 0.6 mm spot size. Two new endovascular devices have been fabricated using the optimized laser joining parameters, which have demonstrated successful device delivery and retrieval, as well as acute biocompatibility.


2015 ◽  
Vol 85 (6) ◽  
pp. 920-926 ◽  
Author(s):  
Ricardo Carvalho Bueno ◽  
Roberta Tarkany Basting

ABSTRACT Objective:  To evaluate the proliferation and morphology of human osteoblasts cultured on two brands of mini-implants after 24, 48, and 72 hours, in addition to the chemical composition found on their surface. Materials and Methods:  Two brands of mini-implant (Morelli and Neodent) were evaluated; polystyrene was used as a control group (n  =  3). Osteoblasts were cultured on the surface of sterilized mini-implants in a CO2 incubator at different time periods (24, 48, and 72 hours). Osteoblast proliferation was quantified by scanning electron microscopy using up to 5000× magnification, and cell morphology was analyzed by a single observer. For the chemical analysis, spectroscopy X-ray fluorescence was used to identify and quantify chemical components on the surface of the mini-implants. Results:  Two-way ANOVA showed no significant interaction between the factors studied (P  =  0.686). A Tukey test revealed no significant difference in osteoblast proliferation between the mini-implants at all studied periods; however, a difference in cell proliferation was detected between the Neodent and the control group (P  =  .025). For all groups, time had a direct and positive effect on osteoblast proliferation (P &lt; .001). The significant elements present in both brands of mini-implants were titanium, aluminum, vanadium, and iron. Conclusions:  Osteoblast proliferation was present on the mini-implants studied, which increased over time; however, no significant difference between brands was observed. No difference was seen between the mini-implants evaluated in terms of chemical composition. Cell adhesion after 72 hours suggests that areas of bone remodeling can be achieved, thus initiating the process of mini-implant anchorage.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
G Karavani ◽  
P Wasserzug-Pash ◽  
T Mordechai-Daniel ◽  
M Klutstein ◽  
T Imbar

Abstract Study question Does human oocytes in-vitro maturation (IVM) effectiveness change throughout childhood, adolescence and adulthood in girls and women undergoing fertility preservation via ovarian tissue cryopreservation (OTC) prior to chemo-radiotherapy exposure? Summary answer The optimal age for IVM is from menarche to 25 years, while pre-menarche girls and women older than 30 years have extremely low maturation rates. What is known already In vitro maturation of oocytes from antral follicles seen during tissue harvesting is a fertility preservation technique with potential advantages over OTC, as mature frozen and later thawed oocyte used for fertilization poses decreased risk of malignant cells re-seeding, as compared to ovarian tissue implantation. We previously demonstrated that IVM performed following OTC in fertility preservation patients, even in pre-menarche girls, yields a fair amount of oocytes available for IVM and freezing for future use. Study design, size, duration A retrospective cohort study, evaluating IVM outcomes in chemotherapy naïve patients referred for fertility preservation by OTC that had oocyte collected from the medium with attempted IVM between 2003 and 2020 in a university affiliated tertiary center. Participants/materials, setting, methods A total of 133 chemotherapy naïve patients aged 1–35 years with attempted IVM were included in the study. The primary outcome was IVM rate in the different age groups – pre-menarche (1–5 years and ≥6 years), post-menarche (menarche–17 years), young adults (18–24 years) and adults (25–29 and 30–35 years). Comparison between paired groups for significant difference in the IVM rate parameter was done using the Tukey’s Studentized Range (HSD) Test. Main results and the role of chance A gradual increase in mean IVM rate was demonstrated in the age groups over 1 to 25 years (4.6% (1–5 years), 23.8% (6 years to menarche) and 28.4% (menarche to 17 years), with a peak of 38.3% in the 18–24 years group, followed by a decrease in the 25–29 years group (19.3%), down to a very low IVM rate (8.9%) in the 30–35 years group. A significant difference in IVM rates was noted between the age extremes – the very young (1–5 years) and the oldest (30–35 years) groups, as compared with the 18–24-year group (p &lt; 0.001). Number of oocytes matured, percent of patients with matured oocytes and overall maturation rate differed significantly (p &lt; 0.001). Limitations, reasons for caution Data regarding ovarian reserve evaluation was not available for most of the patients, due to our pre-op OTC procedures protocol. None of our patients have used their frozen in-vitro matured oocytes, as such further implications of age on in-vitro matured oocytes quality and implantation potential has yet to be evaluated. Wider implications of the findings: Our finding of extremely low success rates in those very young (under 6 years) and older (≥30 years) patients suggest that IVM of oocyte retrieved during OTC prior to chemotherapy should not be attempted in these age group. Trial registration number N/A


2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Blerim Kamberi ◽  
Donika Bajrami ◽  
Miranda Stavileci ◽  
Shuhreta Omeragiq ◽  
Fatmir Dragidella ◽  
...  

Aim. The purpose of this in vitro study was to assess the antimicrobial efficacy of Biopure MTAD against E. faecalis in contaminated root canals. Materials and Methods. Forty-two single rooted extracted human teeth were inoculated with E. faecalis and incubated for four weeks. The samples were divided in two control and five experimental groups irrigated with 1.5% sodium hypochlorite solution (NaOCl); 3% NaOCl; BioPure MTAD; 1.5% NaOCl/17% EDTA; or 3% NaOCl/17% EDTA. After a one-week incubation, complete disinfection was confirmed by the absence of turbidity in the incubation media. Dentin shavings were taken from samples with no turbidity to verify whether E. faecalis was present in dentin tubules. Results were analyzed statistically using Fisher's exact test, with the level of significance set at . Results. Statistical analysis of the data obtained at Day 7 and after dentin shaving analysis showed that BioPure MTAD had significantly greater antibacterial activity than 1.5% NaOCl, 1.5% NaOCl/17% EDTA and 3% NaOCl/17% EDTA. No significant difference was detected between MTAD and 3% NaOCl. Conclusions. These findings suggest that BioPure MTAD possesses superior bactericidal activity compared with NaOCl and EDTA against E. faecalis.


2010 ◽  
Vol 31 (8) ◽  
pp. 1521-1528 ◽  
Author(s):  
L. Goubergrits ◽  
B. Thamsen ◽  
A. Berthe ◽  
J. Poethke ◽  
U. Kertzscher ◽  
...  

2016 ◽  
Vol 17 (12) ◽  
pp. 997-1002 ◽  
Author(s):  
Fahad I Alkhudhairy ◽  
Zeeshan H Ahmad

ABSTRACT Introduction Various bulk-fill materials depending on their composition, viscosity, and flow ability have different physical and mechanical properties. The aim of this in vitro study was to determine and compare the shear bond strength and microleakage properties of activa restorative with other bulk-fill restorative materials surefil (SDR), Biodentine, ever X posterior. Materials and methods Forty permanent premolars were selected for shear bond strength, and 20 permanent premolars were selected with class II cavities on mesial and distal side for microleakage. Universal testing device was used to assess the shear bond strength. Microleakage was checked using dye penetration method under a stereomicroscope. Mean and standard deviation values were calculated from the recorded values. Intergroup comparison was done by one-way analysis of variance (ANOVA) followed by pairwise comparison using Tukey honestly significant difference (HSD) post hoc test. Results The mean shear bond strength was highest for SDR surefil followed by Ever X posterior, Bioactive restorative, and Biodentine respectively. In this study, SDR (surefil) showed better shear bond strength and better microleakage properties compared with the other test materials (F = 186.7157, p < 0.05). Conclusion The result of this study showed that flowable and fiber-reinforced composites have better shear bond strength and microleakage properties. Clinical significance Flowable bulk-fill composite resins can be used as dentin substitutes because of its superior properties. How to cite this article Alkhudhairy FI, Ahmad ZH. Comparison of Shear Bond Strength and Microleakage of Various Bulk-fill Bioactive Dentin substitutes: An in vitro study. J Contemp Dent Pract 2016;17(12):997-1002.


2020 ◽  
Vol 11 (2) ◽  
pp. 160-166
Author(s):  
Mohammad Javad Moghaddas ◽  
Horieh Moosavi ◽  
Sara Yaghoubirad ◽  
Nasim Chiniforush

Introduction: The purpose of this study was to compare the effect of the bioactive glass, the glass ionomer, and the Erbium YAG laser as liners on the remineralization of the affected dentin. Methods: The present study was conducted on 64 healthy extracted human molars divided into 4 groups, 1 control group and 3 experimental groups. After artificially inducing dentinal caries lesions, each of the experimental groups was applied to the cavity floor and then restored with a composite. The samples were stored after thermocycling in an incubator for two months. Finally, the hardness of the cavity floor was measured at 3 depths of 20, 50 and 100 μm by the Vickers microhardness tester. The dentin conditions underneath the liners were also evaluated with FESEM. Statistical analysis was performed by two-way ANOVA and the post-hoc Games-Howell test (P<0.05). Results: Among the groups, the lowest microhardness value was in the control group (P<0.05) except at a depth of 100 μm; therefore, there was no significant difference between the control group and the bioactive glass (P>0.05). The laser group had the highest microhardness value, which was significantly different from the control group (P<0.05). There was a significant difference between the laser and bioactive glass (P<0.05), except at a depth of 20 μm. The laser and glass ionomer had only a significant difference at a depth of 100 μm (P<0.05). The microhardness value induced by glass ionomer was higher than bioactive glass, which in no depth was significant (P>0.05). Partial dentinal tubule occlusion was observed with FESEM in each of the experimental groups as compared to the control group. Conclusion: The microhardness values were higher in all groups than in the control group. The laser might be more successful in remineralization than the other ones.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Gollshang Ahmad Mhammed Dalloo ◽  
Bestoon Mohammed Faraj ◽  
Abdulsalam Rasheed Al-Zahawi

Purpose. This study evaluates the effect of bleaching before or after veneer preparation and the depth of preparation on color masking ability of laminate veneers. Methods. Sixty extracted premolars were artificially stained to vita shade A4, verified by digital spectrophotometer (Vita Easy Shade V), and then divided into three groups: NB = nonbleached , BBP = bleaching before preparation, and BAP = bleaching after preparation. Based on the preparation depths, each group was further divided into two subgroups: S 1 = 0.5   mm and S 2 = 1.0   mm . BBP and BAP were subjected to one session of in-office bleaching using 35% hydrogen peroxide. IPS e-max CAD veneers of 0.5 and 1.0 mm thickness (corresponding to the preparation depths) of the same shade and translucency (HT A1) were cemented immediately to the bleached surfaces. Immediately after cementation, the color change Δ E between the baseline (after staining) and the resulted shades was measured using the Vita Easy Shade V digital spectrophotometer and CIELab color system. Results. Bleached groups exhibited a significant Δ E value compared to the nonbleached group ( p < 0.05 ). BAP showed the highest Δ E value. No significant difference was found between BBP and BAP. S2 revealed a significant Δ E value than S1 ( p < 0.05 ). No significant difference was found between S1of BAP and S2 of NB, BBP, and BAP ( p > 0.05 ). Regarding the color coordinates, the difference between the tested groups was highly significant in lightness ( Δ L ∗ ) ( p < 0.001 ), while no significant differences were found in green/red value ( Δ a ∗ ) and yellow/blue value ( Δ b ∗ ) ( p > 0.05 ). Conclusions. In cases of severe tooth discoloration, one session of in-office bleaching before or after veneer preparation and the preparation depth do not influence the color masking ability of laminate veneers.


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