scholarly journals In Vitro Study of Endotoxin Adsorption by a Polymyxin B-Immobilized Fiber Column

2018 ◽  
Vol 46 (4) ◽  
pp. 269-273 ◽  
Author(s):  
Chizuru Yamashita ◽  
Kazuhiro Moriyama ◽  
Daisuke Hasegawa ◽  
Yu Kato ◽  
Toshikazu Sakai ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Fixed Time ◽  
Polymyxin B ◽  
Therapeutic Interventions ◽  
Fixed Rate ◽  
Priming Volume ◽  
Control Column ◽  
Fetal Bovine ◽  
The Difference

Background: Polymyxin B-immobilized fiber (PMX-F) columns are used as therapeutic interventions for septic shock. The clinical efficacy has been reported for 2-h applications, but their ability to adsorb endotoxin over longer treatments has not been fully elucidated. We hypothesized that PMX-F columns are capable of endotoxin removal for more than 2 h. Method: We designed closed circuits incorporating either a PMX-F column with an 8.5-mL priming volume (PMX-01R) or a sham-control column, and used inactivated fetal bovine serum as the circulating perfusate. Endotoxin was continuously injected at a fixed rate for 24 h, and perfusate endotoxin concentrations were measured at fixed time points. PMX-01R endotoxin adsorption was calculated from the difference in the endotoxin concentrations. Results: PMX-01R endotoxin adsorption increased continuously in a virtually linear manner. Conclusions: The PMX-01R column showed sustained endotoxin adsorption for at least 24 h. This indicated that PMX-F columns would be capable of clinical endotoxin removal for 24 h.

scholarly journals Comparison of Fracture Resistance in Thermal and Self-Curing Acrylic Resins—An In Vitro Study

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1234
Author(s):  
António Sérgio Silva ◽  
Aurora Carvalho ◽  
Pedro Barreiros ◽  
Juliana de Sá ◽  
Carlos Aroso ◽  
...  
Keyword(s):  
Fracture Resistance ◽  
Research Work ◽  
Testing Machine ◽  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Acrylic Resin ◽  
Thermosetting Resins ◽  
Acrylic Resins ◽  
The Difference

Thermal and self-curing acrylic resins are frequently and versatilely used in dental medicine since they are biocompatible, have no flavor or odor, have satisfactory thermal qualities and polishing capacity, and are easy and fast. Thus, given their widespread use, their fracture resistance behavior is especially important. In this research work, we comparatively analyzed the fracture resistance capacity of thermo and self-curing acrylic resins in vitro. Materials and Methods: Five prosthesis bases were created for each of the following acrylic resins: Lucitone®, ProBase®, and Megacryl®, which were submitted to different forces through the use of the CS® Dental Testing Machine, usually mobilized in the context of fatigue tests. To this end, a point was defined in the center of the anterior edge of the aforementioned acrylic resin bases, for which the peak tended until a fracture occurred. Thermosetting resins were, on average, more resistant to fracture than self-curable resins, although the difference was not statistically significant. The thermosetting resins of the Lucitone® and Probase® brands demonstrated behavior that was more resistant to fracture than the self-curing homologues, although the difference was not statistically significant. Thermosetting resins tended to be, on average, more resistant to fracture and exhibited the maximum values for impact strength, compressive strength, tensile strength, hardness, and dimensional accuracy than self-curing resins, regardless of brand.

scholarly journals Effect of Citric Acid on Color Changes of Calcium Silicate-Based Cements an In Vitro Study

2021 ◽  
Vol 11 (5) ◽  
pp. 2339
Author(s):  
Joanna Metlerska ◽  
Till Dammaschke ◽  
Mariusz Lipski ◽  
Irini Fagogeni ◽  
Anna Machoy-Mokrzyńska ◽  
...  
Keyword(s):  
Citric Acid ◽  
Calcium Silicate ◽  
In Vitro Study ◽  
Vitro Study ◽  
Color Measurement ◽  
Color Changes ◽  
Naked Eye ◽  
Root Canal Irrigants ◽  
The Difference

The aim of the present in vitro study was to investigate the effects of 10% and 40% citric acid (CA) on the color of calcium silicate–based cements (CSCs) in comparison to the effects of common root canal irrigants. Samples of six CSCs (n = 6)—ProRoot MTA (Dentsply, Tulsa, OK, USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), MTA Plus (Avalon Biomed Inc, by Prevest Denpro Limited, Jammu, India), MTA Repair HP (Angelus, Londrina, PR, Brazil), Ortho MTA (BioMTA, Seoul, Korea), and Retro MTA (BioMTA, Seoul, Korea)—were immersed in 10% and 40% CA as well as 15% EDTA, 2% NaOCl, 2% CHX, and 0.9% NaCl for 15 min, 1 h, and 24 h. ΔE values, representing the difference between the final and baseline values of the color components, were then determined using a VITA Easyshade Compact 5.0 spectrophotometer. Naked-eye evaluation of the changes in color and structures of the materials was performed using our own scale. Upon immersion of the materials in both 10% and 40% CA, there were statistically significant differences between spectrophotometric color measurement results for all CSCs (P < 0.05). However, CA does not cause dark discoloration, observable with the naked eye, of any of the materials, such as NaOCl and CHX. Significant statistical differences were also found between all CSCs in terms of submersion duration (P < 0.05). CA, which could be an alternative to EDTA use, caused greater CSCs discoloration and changed some of their structures. Unless required by the therapeutic procedure, clinicians should pay attention to the fact that the irrigant may affect the CSCs discoloration and minimize the contact time of irrigant with CSCs.

scholarly journals Scanning Accuracy of Bracket Features and Slot Base Angle in Different Bracket Materials by Four Intraoral Scanners: An In Vitro Study

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 365
Author(s):  
Seon-Hee Shin ◽  
Hyung-Seog Yu ◽  
Jung-Yul Cha ◽  
Jae-Sung Kwon ◽  
Chung-Ju Hwang
Keyword(s):  
Stainless Steel ◽  
In Vitro Study ◽  
Sem Images ◽  
Polycrystalline Alumina ◽  
Base Angle ◽  
Accurate Expression ◽  
Dental Model ◽  
Alumina Composite ◽  
The Difference

The accurate expression of bracket prescription is important for successful orthodontic treatment. The aim of this study was to evaluate the accuracy of digital scan images of brackets produced by four intraoral scanners (IOSs) when scanning the surface of the dental model attached with different bracket materials. Brackets made from stainless steel, polycrystalline alumina, composite, and composite/stainless steel slot were considered, which have been scanned from four different IOSs (Primescan, Trios, CS3600, and i500). SEM images were used as references. Each bracket axis was set in the reference scan image, and the axis was set identically by superimposing with the IOS image, and then only the brackets were divided and analyzed. One-way analysis of variance (ANOVA) was used to compare the differences. The difference between the manufacturer’s nominal torque and bracket slot base angle was 0.39 in SEM, 1.96 in Primescan, 2.04 in Trios, and 5.21 in CS3600 (p < 0.001). The parallelism, which is the difference between the upper and lower angles of the slot wall, was 0.48 in SEM, 7.00 in Primescan, 5.52 in Trios, 6.34 in CS3600, and 23.74 in i500 (p < 0.001). This study evaluated the accuracy of the bracket only, and it must be admitted that there is some error in recognizing slots through scanning in general.

scholarly journals Nephrotoxicity Of Polymyxin B: Experimental Study In Cells And Implications For Nursing Practice

2014 ◽  
Vol 48 (2) ◽  
pp. 272-277 ◽  
Author(s):  
Luciana Barros de Moura Neiva ◽  
Fernanda Teixeira Borges ◽  
Mirian Watanabe ◽  
Edson de Andrade Pessoa ◽  
Dulce Aparecida Barbosa ◽  
...  
Keyword(s):  
Fluorescent Dyes ◽  
Cell Damage ◽  
Kidney Injury ◽  
In Vitro Study ◽  
Polymyxin B ◽  
Concentration Cell ◽  
Tubular Cells ◽  
Risk Patients ◽  
Proximal Tubular

The aim of the study was to characterize the cell damage mechanisms involved in the pathophysiology of cytotoxicity of polymyxin B in proximal tubular cells (LLC - PK1) and discuss about the nurses interventions to identify at risk patients and consider prevention or treatment of nephrotoxicity acute kidney injury. This is a quantitative experimental in vitro study, in which the cells were exposed to 375μM polymyxin B sulfate concentration. Cell viability was determined by exclusion of fluorescent dyes and morphological method with visualization of apoptotic bodies for fluorescence microscopy. Cells exposed to polymyxin B showed reduced viability, increased number of apoptotic cells and a higher concentration of the enzyme lactate dehydrogenase. The administration of polymyxin B in vitro showed the need for actions to minimize adverse effects such as nephrotoxicity.


EVALUATION OF THE DISSOLVING EFFICACY OF ESSENTIAL OILS ON ENDODONTIC OBTURATING MATERIALS: AN IN VITRO STUDY.

2021 ◽  
pp. 66-68
Author(s):  
Rakesh Pyla ◽  
Jai Kiran Killada ◽  
V Raja Sekhar
Keyword(s):  
Essential Oils ◽  
Epoxy Resin ◽  
In Vitro Study ◽  
Vitro Study ◽  
Lavender Oil ◽  
Citronella Oil ◽  
Gutta Percha ◽  
Lemon Oil ◽  
The Difference

Aim:Endodontic retreatment is a procedure that removes the lling materials from the root canals followed by their cleaning, shaping and obturation. This in-vitro study aimed to compare and evaluate the ability of various essential oils as solvents in dissolving gutta-percha, epoxy resin, and zinc oxide eugenol (ZOE) cements. Materials and methods: A total of 28 cylindrical specimens in each group ZOE, epoxy resin, 28 ISO size 40 gutta-percha cones were prepared and divided into four groups for immersion in the different solvents, i.e. lemon oil, citronella oil, lavender oil, and TCE(Tetrachloroethylene (control)) for 5 minutes. The obturating materials dissolution in the solvents were obtained by the difference between the pre-immersion original weight and the post-immersion weight on a digital analytical scale. Data were statistically analysed by a paired t-test and Analysis of Variance (ANOVA) (p < 0.05). Results: Order of efcacy of dissolution of essential oils was found to be lemon oil > Citronella oil > Lavender oil and was highly signicant (p < 0.01). In all the solvents, Gutta-percha showed maximum dissolution (Fvalue:149.56) followed by ZOE(89.07 ) and resin sealer least (23.86). Conclusion: It can be concluded that the lemon oil can be used as a solvent for dissolving obturating materials.

scholarly journals Comparison of the Remineralizing Effect of Brushing with Aloe vera versus Fluoride Toothpaste

2020 ◽  
Author(s):  
Teresa Al Haddad ◽  
Elie Khoury ◽  
Nada Farhat Mchayleh
Keyword(s):  
Repeated Measures ◽  
Aloe Vera ◽  
In Vitro Study ◽  
P Value ◽  
Fluoride Toothpaste ◽  
Before And After ◽  
The Difference ◽  
Group B ◽  
Ca:P Ratio

Abstract Objectives The aim of the present in vitro study is to compare the remineralization brushing effect of three toothpastes and Aloe vera (AV) gel. Materials and Methods Forty sound extracted teeth were placed in a demineralizing solution for 4 days and randomly assigned to four groups: group A: 1,450-ppm fluoride toothpaste; group B: AV nonfluoridated toothpaste; group C: AV 1,000-ppm fluoridated toothpaste; and group D: AV gel. A 3-minute pH cycling was performed twice a day for each group for 12 days. Specimens were analyzed before and after by scanning electron microscope—energy dispersive X-ray. Statistical analysis The outcomes were analyzed by Kolmogorov–Smirnov’s tests, repeated-measures analyses of variance followed by univariate analyses, and Bonferroni’s multiple comparisons tests to compare the calcium-to-phosphorus (Ca:P) ratio within time among toothpaste groups. Results Following remineralization, the Ca:P ratio increased in all groups. The difference of the Ca:P ratio was not significant between groups C, D, and A. The mean ratio was significantly lower in group B (p-value = 0.026). Conclusions The AV gel demonstrated a remineralization capacity equal to that of the 1,450-ppm fluoride toothpaste. In contrast, fluoride-free AV toothpaste showed a lower remineralization efficiency. Further studies are required to understand its mechanism.

scholarly journals The IG- file use to Gauge the Apical Diameter in Endodontics: An In Vitro Study

2018 ◽  
Vol 12 (1) ◽  
pp. 638-646 ◽  
Author(s):  
Massimo Amato ◽  
Alfredo Iandolo ◽  
Giuseppe Pantaleo ◽  
Dina Abtellatif ◽  
Michele Simeone ◽  
...  
Keyword(s):  
Measurement Accuracy ◽  
Reference Value ◽  
In Vitro Study ◽  
Vitro Study ◽  
Root Canals ◽  
New Instrument ◽  
Clinician Experience ◽  
Incorrect Measurement ◽  
The Difference

Aim: The aim of this study was to evaluate the efficacy of the IG-file, a new instrument designed for apical diameter gauging. Materials and Methods: After shaping with F1 Universal Protaper, 60 roots were randomly divided into two groups and assigned to two operators, One Expert in Endodontics (EO) and One Unexpert (UO). In each sample, after canal curvatures have been detected, the apical diameters were measured with the IG-file and the K-NiTi. The results were compared with the reference value obtained by retrograde apical gauging. The data were statistically analyzed. Results: Among 60 samples, 10% of errors were recorded when the IG-files were used; in the K-NiTi group the incorrect measurements were 70%. In both groups (expert and unexpert) the IG-file measurements were more accurate than the K-NiTi (90 vs 33 and 90 vs 26,7). The differences were statistically significant. In curved canals, the difference between measurement rates performed with both instruments was statistically significant (85,7% IG-file vs 28,6% K-NiTi) as well as for the samples without curvatures (92,3% IG file vs 30,8% NiTi file). In root canals without curvatures overestimation errors in K-NiTi file group are more frequent than underestimation errors. This difference was statistically significant. Conclusion: A proper gauging of the apical diameter has a key role in endodontic therapy; an incorrect measurement can lead to clinical failures. This “in vitro” study highlights that IG-file improves measurement accuracy independently from clinician experience. Furthermore, in curved canals, the IG-file is more accurate than K-NiTi.

scholarly journals Impact of Bleaching before or after Veneer Preparation on Color Masking Ability of Laminate Veneers: An In Vitro Study

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Gollshang Ahmad Mhammed Dalloo ◽  
Bestoon Mohammed Faraj ◽  
Abdulsalam Rasheed Al-Zahawi
Keyword(s):  
Hydrogen Peroxide ◽  
Color Change ◽  
In Vitro Study ◽  
Tooth Discoloration ◽  
Significant Difference ◽  
Color System ◽  
The Difference ◽  
Laminate Veneers ◽  
Cielab Color

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.

scholarly journals A Comparative Evaluation of Effects of Conventional and Herbal Irrigants on Working Length Determination by Third Generation Apex Locator–An In Vitro Study

2020 ◽  
Vol 8 (02) ◽  
pp. 44-48
Author(s):  
Niharika Patalbansi ◽  
Yogesh Kumar ◽  
Neetu Jindal ◽  
Renu Aggarwal ◽  
Shefali Goyal
Keyword(s):  
Green Tea ◽  
Aloe Vera ◽  
In Vitro Study ◽  
Length Estimation ◽  
Working Length ◽  
Dry Conditions ◽  
Recorded Data ◽  
Length Determination ◽  
The Difference

Abstract Introduction The establishment of accurate working length is one of the most critical steps in endodontic therapy from the biomechanical and obturation points of view. Traditionally, the use of radiography and tactile sense methods were used for working length estimation, but recently, the use of electronic apex locator (EAL) has come into existence. The aim was to evaluate the effect of conventional and herbal irrigants on working length determination by Root ZX. Materials and Methods A total of 110 extracted single rooted teeth were taken. Standard access cavities were prepared and samples were randomly divided into 11 groups (n = 10) according to the type of irrigating solutions used. The actual root canal length was measured, and the readings in dry conditions and wet conditions were recorded. The point where Root ZX showed beep was recorded and difference was recorded as well. The recorded data was calculated and statistically analyzed using unpaired t-test. Result In dry conditions, only saline, H2O2, Aloe vera, and green tea gave exact working length using apex locator values. Whereas in wet conditions, only Aloe vera and green tea gave exact working length. Conclusion Although the irrigants and dry conditions influenced the results, Root ZX can be considered to be accurate, and the difference was within the clinically acceptable range and not statistically significant.

scholarly journals Influence of Dental Composite Viscosity in Attachment Reproduction: An Experimental in Vitro Study

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4001
Author(s):  
Vincenzo D’Antò ◽  
Simone Muraglie ◽  
Beatrice Castellano ◽  
Ettore Candida ◽  
Maria Francesca Sfondrini ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Dental Composite ◽  
Maximum Deviation ◽  
Force System ◽  
Maximum Value ◽  
Significant Difference ◽  
The Difference ◽  
Level Of Significance ◽  
The Ideal

Background: Attachments are composite auxiliaries that are used during a clear aligner orthodontic therapy to achieve difficult tooth movements. Two important factors are the planned configuration and the actual position of these auxiliary elements to obtain the desired force system. The aim of the present study was to evaluate the role of different composite materials in the correct reproduction of attachment shape and position. Methods: The materials that were considered in the study were a flowable resin, a dental restorative material, and an orthodontic composite. The attachments were created on three models of extracted teeth. Once the impressions were performed, 25 attachments of different shapes were added onto each virtual model to obtain the necessary templates to make the attachments. Each tested material was used to create a set of 25 attachments that were then scanned with an accuracy of 10μm. The resultant STL (stereolithography) files were superimposed onto the ones from the initial virtual plan, through Geomagic software, and the aligned scans were then compared while using a color map. The parameters that were calculated to make a comparison between the created attachments and the ideal ones were the maximum deviation in defect and in excess, the overflow, and the volume’s difference. In addition to these measurements comparing the three above-mentioned groups, the difference in volume between all the ideal and realized samples were analyzed. To test for differences among the three groups, a one-way Analysis of variance (ANOVA) was used with a Bonferroni post-hoc test. The level of significance was set at p < 0.05. Results: No statistically significant results were found between the three groups regarding the maximum value in defect, the maximum value in excess, and the minimum value as control, while a statistically significant difference was found between the overflow of orthodontic resin when compared to the flowable composite. Conclusions: The three materials that were used in this study were appropriate for attachment fabrication. The fidelity of attachment reproduction was similar when using the three different composites. The orthodontic composite showed more overflow when compared with the flowable one.

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