scholarly journals Trueness of full-arch IO scans estimated based on 3D translational and rotational deviations of single teeth—an in vitro study

2021 ◽  
Author(s):  
Johanna Radeke ◽  
Annike B. Vogel ◽  
Falko Schmidt ◽  
Fatih Kilic ◽  
Stefan Repky ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
In Vitro Study ◽  
Confocal Laser ◽  
Anterior Crowding ◽  
Six Degrees Of Freedom ◽  
Staff Members ◽  
Total Displacement ◽  
Dental Staff ◽  
Novel Method

Abstract Objectives To three-dimensionally evaluate deviations of full-arch intraoral (IO) scans from reference desktop scans in terms of translations and rotations of individual teeth and different types of (mal)occlusion. Materials and methods Three resin model pairs reflecting different tooth (mal)positions were mounted in the phantom head of a dental simulation unit and scanned by three dentists and three non-graduate investigators using a confocal laser IO scanner (Trios 3®). The tooth-crown surfaces of the IO scans and reference scans were superimposed by means of best-fit alignment. A novel method comprising the measurement of individual tooth positions was used to determine the deviations of each tooth in the six degrees of freedom, i.e., in terms of 3D translation and rotation. Deviations between IO and reference scans, among tooth-(mal)position models, and between dentists and non-graduate investigators were analyzed using linear mixed-effects models. Results The overall translational deviations of individual teeth on the IO scans were 76, 32, and 58 µm in the lingual, mesial, and intrusive directions, respectively, resulting in a total displacement of 114 µm. Corresponding rotational deviations were 0.58° buccal tipping, 0.04° mesial tipping, and 0.14° distorotation leading to a combined rotation of 0.78°. These deviations were the smallest for the dental arches with anterior crowding, followed by those with spacing and those with good alignment (p < 0.05). Results were independent of the operator’s level of education. Conclusions Compared to reference desktop scans, individual teeth on full-arch IO scans showed high trueness with total translational and rotational deviations < 115 µm and < 0.80°, respectively. Clinical relevance Available confocal laser IO scanners appear sufficiently accurate for diagnostic and therapeutic orthodontic applications. Results indicate that full-arch IO scanning can be delegated to non-graduate dental staff members.

scholarly journals Efficient and selective catalytic hydroxylation of unsaturated plant oils: a novel method for producing anti-pathogens

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Ahmed M. Senan ◽  
Binru Yin ◽  
Yaoyao Zhang ◽  
Mustapha M. Nasiru ◽  
Yong‐Mei Lyu ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
In Vitro Study ◽  
Functional Method ◽  
Plant Oils ◽  
Main Process ◽  
Catalytic Method ◽  
Novel Method ◽  
Pharmaceutical Industries ◽  
Increasing Demand

AbstractWith the increasing demand for antimicrobial agents and the spread of antibiotic resistance in pathogens, the exploitation of plant oils to partly replace antibiotic emerges as an important source of fine chemicals, functional food utility and pharmaceutical industries. This work introduces a novel catalytic method of plant oils hydroxylation by Fe(III) citrate monohydrate (Fe3+-cit.)/Na2S2O8 catalyst. Methyl (9Z,12Z)-octadecadienoate (ML) was selected as an example of vegetable oils hydroxylation to its hydroxy-conjugated derivatives (CHML) in the presence of a new complex of Fe(II)-species. Methyl 9,12-di-hydroxyoctadecanoate 1, methyl-9-hydroxyoctadecanoate 2 and methyl (10E,12E)-octadecanoate 3 mixtures is produced under optimized condition with oxygen balloon. The specific hydroxylation activity was lower in the case of using Na2S2O8 alone as a catalyst. A chemical reaction has shown the main process converted of plantoils hydroxylation and (+ 16 Da) of OH- attached at the methyl linoleate (ML-OH). HPLC and MALDI-ToF-mass spectrometry were employed for determining the obtained products. It was found that adding oxidizing agents (Na2S2O8) to Fe3+ in the MeCN mixture with H2O would generate the new complex of Fe(II)-species, which improves the C-H activation. Hence, the present study demonstrated a new functional method for better usage of vegetable oils.Producing conjugated hydroxy-fatty acids/esters with better antipathogenic properties. CHML used in food industry, It has a potential pathway to food safety and packaging process with good advantages, fundamental to microbial resistance. Lastly, our findings showed that biological monitoring of CHML-minimum inhibitory concentration (MIC) inhibited growth of various gram-positive and gram-negative bacteria in vitro study. The produced CHML profiles were comparable to the corresponding to previousstudies and showed improved the inhibition efficiency over the respective kanamycin derivatives.

Endotracheal tubes coated with a broad-spectrum antibacterial ceragenin reduce bacterial biofilm in an in vitro bench top model

2021 ◽  
Author(s):  
María Consuelo Latorre ◽  
María Jesús Pérez-Granda ◽  
Paul B Savage ◽  
Beatriz Alonso ◽  
Pablo Martín-Rabadán ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
In Vitro Study ◽  
Bacterial Biofilm ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Endotracheal Tubes ◽  
Clinical Strains ◽  
Number Of Cells

Abstract Background Ventilator-associated pneumonia is one of the most common nosocomial infections, caused mainly by bacterial/fungal biofilm. Therefore, it is necessary to develop preventive strategies to avoid biofilm formation based on new compounds. Objectives We performed an in vitro study to compare the efficacy of endotracheal tubes (ETTs) coated with the ceragenin CSA-131 and that of uncoated ETTs against the biofilm of clinical strains of Pseudomonas aeruginosa (PA), Escherichia coli (EC) and Staphylococcus aureus (SA). Methods We applied an in vitro bench top model using coated and uncoated ETTs that were treated with three different clinical strains of PA, EC and SA for 5 days. After exposure to biofilm, ETTs were analysed for cfu count by culture of sonicate and total number of cells by confocal laser scanning microscopy. Results The median (IQR) cfu/mL counts of PA, EC and SA in coated and uncoated ETTs were, respectively, as follows: 1.00 × 101 (0.0–3.3 × 102) versus 3.32 × 109 (6.6 × 108–3.8 × 109), P &lt; 0.001; 0.0 (0.0–5.4 × 103) versus 1.32 × 106 (2.3 × 103–5.0 × 107), P &lt; 0.001; and 8.1 × 105 (8.5 × 101–1.4 × 109) versus 2.7 × 108 (8.6 × 106–1.6 × 1011), P = 0.058. The median (IQR) total number of cells of PA, EC and SA in coated and non-coated ETTs were, respectively, as follows: 11.0 [5.5–not applicable (NA)] versus 87.9 (60.5–NA), P = 0.05; 9.1 (6.7–NA) versus 62.6 (42.0–NA), P = 0.05; and 97.7 (94.6–NA) versus 187.3 (43.9–NA), P = 0.827. Conclusions We demonstrated significantly reduced biofilm formation in coated ETTs. However, the difference for SA was not statistically significant. Future clinical studies are needed to support our findings.

scholarly journals In Vitro Study of Calcium Microsecond Electroporation of Prostate Adenocarcinoma Cells

Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5406 ◽  
Author(s):  
Aleksander Kiełbik ◽  
Wojciech Szlasa ◽  
Olga Michel ◽  
Anna Szewczyk ◽  
Mounir Tarek ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Cells ◽  
Calcium Binding ◽  
In Vitro Study ◽  
Vitro Study ◽  
Dynamics Simulation ◽  
Confocal Laser ◽  
Prostate Cancer Cells ◽  
Voltage Pulses

Electroporation, applied as a non-thermal ablation method has proven to be effective for focal prostate treatment. In this study, we performed pre-clinical research, which aims at exploring the specific impact of this so-called calcium electroporation on prostate cancer. First, in an in-vitro study of DU 145 cell lines, microsecond electroporation (μsEP) parameters were optimized. We determined hence the voltage that provides both high permeability and viability of these prostate cancer cells. Subsequently, we compared the effect of μsEP on cells’ viability with and without calcium administration. For high-voltage pulses, the cell death’s mechanism was evaluated using flow-cytometry and confocal laser microscopy. For lower-voltage pulses, the influence of electroporation on prostate cancer cell mobility was studied using scratch assays. Additionally, we applied calcium-binding fluorescence dye (Fluo-8) to observe the calcium uptake dynamic with the fluorescence microscopy. Moreover, the molecular dynamics simulation visualized the process of calcium ions inflow during μsEP. According to our results calcium electroporation significantly decreases the cells viability by promoting apoptosis. Furthermore, our data shows that the application of pulsed electric fields disassembles the actin cytoskeleton and influences the prostate cancer cells’ mobility.

Foot Movement and Tendon Excursion: An In Vitro Study

1994 ◽  
Vol 15 (7) ◽  
pp. 386-395 ◽  
Author(s):  
Beat Hintermann ◽  
Benno M. Nigg ◽  
Christian Sommer
Keyword(s):  
Degrees Of Freedom ◽  
Function Analysis ◽  
In Vitro Study ◽  
Tibialis Posterior ◽  
Flexor Hallucis Longus ◽  
Moment Arms ◽  
In Vitro Investigation ◽  
Flexion Extension ◽  
Tendon Excursion

The purpose of this study was to determine tendon excursions resulting from selected foot movement and to derive moment arms with respect to the eversion-inversion and flexion-extension axes of the foot. A lower legholding device with 6 degrees of freedom was used for the in vitro investigation of 15 fresh foot-leg specimens. Although high variation among the subjects existed, there was a pronounced uniformity of tendon excursion throughout a given foot eversion-inversion or flexion-extension range of motion. With reference to the tibialis posterior (1.00), average inverter moment arms with respect to the foot eversion-inversion axis were found to be as follows: flexor digitorum longus, 0.75; flexor hallucis longus, 0.62; tibialis anterior, 0.59; soleus, 0.24; extensor hallucis longus, 0.22; extensor digitorum longus, −0.26; peroneus longus, −0.82; and peroneus brevis, −0.85. A trend toward decreasing evertor/invertor moment arms was observed during the ranges of foot eversion, as well as when the foot was in flexion. Flexor and extensor moment arms were found to be substantially dependent on foot flexion-extension angle. Increasing flexor moment arms were observed when rotating the foot throughout the range from extension to flexion. The obtained results may have significant implications in foot surgery, muscle function analysis, and general considerations of foot function.

Using Navi-Robot and a CT Scanner to Guide Biopsy Needles

2017 ◽  
Vol 11 (3) ◽  
pp. 450-458 ◽  
Author(s):  
Mario Donnici ◽  
◽  
Giorgia Lupinacci ◽  
Paola Nudo ◽  
Michele Perrelli ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Needle Insertion ◽  
Frame Of Reference ◽  
Ct Scanner ◽  
Desktop Computer ◽  
Six Degrees Of Freedom ◽  
Points Of Interest ◽  
Entry Points ◽  
Needle Entry

Purpose of this study was to control the suitability of Navi-Robot, a robotic system developed by our research group, to guide percutaneous needle placement under computed tomography (CT) in order to achieve lower radiation exposure and a shorter procedure. The system consists of a high precision six-degrees-of-freedom self-balanced arm, able to move both in passive and active modes, which allows the physician an accurate needle-insertion. The target and the needle entry points are selected by the surgeon on a desktop computer, that acquires DICOM images from the CT scan, and that, using software developed for this purpose, detects also the position of at least three radio opaque markers placed on the patient or on the stretcher. Once these data are obtained, a new system of reference is established based on the markers position, obtaining the coordinates of target and entry point in the new frame of reference. Going then to touch the tip of the spheres with the tip of the robot end effector in passive mode, and recording their position, the robot learns where the two points of interest are located in its frame of reference. A first test was performed on a Plexiglas board; the accuracy achieved was measured as the distance between the needle tip and the target. The results of the in vitro experiment showed that the system is able to reach the target with an accuracy of 1.2 mm.

scholarly journals Effect of Hydrogen and Carbamide Peroxide in Bleaching, Enamel Morphology, and Mineral Composition: In vitro Study

2017 ◽  
Vol 18 (7) ◽  
pp. 576-582 ◽  
Author(s):  
Carmen Llena ◽  
Leopoldo Forner ◽  
Irene Esteve
Keyword(s):  
Mineral Composition ◽  
Laser Scanning ◽  
Morphological Changes ◽  
Treatment Protocol ◽  
Environmental Scanning Electron Microscopy ◽  
In Vitro Study ◽  
Confocal Laser ◽  
Carbamide Peroxide ◽  
Tooth Color

ABSTRACT Aim The aim of the study was to evaluate the bleaching effect, morphological changes, and variations in calcium (Ca) and phosphate (P) in the enamel with hydrogen peroxide (HP) and carbamide peroxide (CP) after the use of different application regimens. Materials and methods Four groups of five teeth were randomly assigned, according to the treatment protocol: HP 37.5% applied for 30 or 60 minutes (HP30, HP60), CP 16% applied for 14 or 28 hours (CP14, CP28). Changes in dental color were evaluated, according to the following formula: ΔE = [(La−Lb)2+(aa−ab)2 + (ba−bb)2]½. Enamel morphology and Ca and P compositions were evaluated by confocal laser scanning microscope and environmental scanning electron microscopy. Results ΔE HP30 was significantly greater than CP14 (10.37 ± 2.65/8.56 ± 1.40), but not between HP60 and CP28. HP60 shows greater morphological changes than HP30. No morphological changes were observed in the groups treated with CP. The reduction in Ca and P was significantly greater in HP60 than in CP28 (p < 0.05). Conclusion Both formulations improved tooth color; HP produced morphological changes and Ca and P a gradual decrease, while CP produced no morphological changes, and the decrease in mineral component was smaller. Clinical significance CP 16% applied during 2 weeks could be equally effective and safer for tooth whitening than to administer two treatment sessions with HP 37.5%. How to cite this article Llena C, Esteve I, Forner L. Effect of Hydrogen and Carbamide Peroxide in Bleaching, Enamel Morphology, and Mineral Composition: In vitro Study. J Contemp Dent Pract 2017;18(7):576-582.

scholarly journals Influence of Remineralizing Dentifrice in the Treatment of Erosive Enamel Lesions

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 ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Laser Scanning ◽  
Tooth Enamel ◽  
In Vitro Study ◽  
Positive Control ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Significant Difference ◽  
Kolmogorov Smirnov

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.

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