Strategies for Improving the Assessment of Dental Fluorosis: Focus on Optical Techniques

1994 ◽  
Vol 8 (1) ◽  
pp. 75-79 ◽  
Author(s):  
B. Angmar-Månsson ◽  
E. De Josselin de Jong ◽  
F. Sundström ◽  
J.J. Ten Bosch
Keyword(s):  
Light Scattering ◽  
Dental Fluorosis ◽  
Ccd Camera ◽  
Laser Fluorescence ◽  
Optical Methods ◽  
Light Illumination ◽  
Initial Caries ◽  
A Charge ◽  
Caries Lesions

In its milder forms, enamel fluorosis is characterized clinically by diffuse opacities. The appearance is due to optical properties of a subsurface or surface porous layer with lower mineral content. These areas usually have texture and color similar to those of initial caries lesions but generally another shape and location. Therefore, several optical methods, previously used to diagnose initial caries lesions, were applied to fluoride-induced opacities on extracted premolars and on incisors of four subjects in vivo. These methods included light-scattering measurements, white light illumination, violet light illumination, ultraviolet illumination, and laser fluorescence. Video images were captured with a charge-coupled-device (CCD) camera, digitized, and computer-processed. It is concluded that the light-scattering monitor can be used for the determination of the local porosity of fluorotic enamel and that the laser fluorescence method might be developed into a method applicable for the assessment of the severity of enamel fluorosis.

Light-based diagnostic methods for the in vivo assessment of initial caries lesions: Laser fluorescence, QLF and OCT

2021 ◽  
Vol 34 ◽  
pp. 102270
Author(s):  
Kyung-Jin Park ◽  
Aline Voigt ◽  
Hartmut Schneider ◽  
Dirk Ziebolz ◽  
Rainer Haak
Keyword(s):  
Diagnostic Methods ◽  
Laser Fluorescence ◽  
Initial Caries ◽  
Caries Lesions ◽  
In Vivo Assessment

scholarly journals Illuminating ALS Motor Neurons With Optogenetics in Zebrafish

2021 ◽  
Vol 9 ◽  
Author(s):  
Kazuhide Asakawa ◽  
Hiroshi Handa ◽  
Koichi Kawakami
Keyword(s):  
Spinal Cord ◽  
Motor Neurons ◽  
Rna Binding ◽  
The Body ◽  
Optical Methods ◽  
Light Illumination ◽  
Whole Cells ◽  
Spinal Motor Neurons ◽  
Spinal Motor

Amyotrophic lateral sclerosis (ALS) is a fatal neurological disorder characterized by progressive degeneration of motor neurons in the brain and spinal cord. Spinal motor neurons align along the spinal cord length within the vertebral column, and extend long axons to connect with skeletal muscles covering the body surface. Due to this anatomy, spinal motor neurons are among the most difficult cells to observe in vivo. Larval zebrafish have transparent bodies that allow non-invasive visualization of whole cells of single spinal motor neurons, from somas to the neuromuscular synapses. This unique feature, combined with its amenability to genome editing, pharmacology, and optogenetics, enables functional analyses of ALS-associated proteins in the spinal motor neurons in vivo with subcellular resolution. Here, we review the zebrafish skeletal neuromuscular system and the optical methods used to study it. We then introduce a recently developed optogenetic zebrafish ALS model that uses light illumination to control oligomerization, phase transition and aggregation of the ALS-associated DNA/RNA-binding protein called TDP-43. Finally, we will discuss how this disease-in-a-fish ALS model can help solve key questions about ALS pathogenesis and lead to new ALS therapeutics.

scholarly journals Effect of Remineralizing Agents on Initial Caries Lesions - Clinical Pilot Study on School-Children

2020 ◽  
pp. 1-6
Author(s):  
Vuokko Anttonen ◽  
A. Poikela ◽  
J. Nikkinen ◽  
K-M. Pasanen ◽  
L. Tjäderhane ◽  
...  
Keyword(s):  
Tooth Brushing ◽  
Laser Fluorescence ◽  
Ion Concentration ◽  
Control Group ◽  
Initial Caries ◽  
Final Study ◽  
Diagnodent Pen ◽  
Molar Teeth ◽  
Group B ◽  
Caries Lesions

Purpose: Enamel remineralization can be improved by increasing salivary calcium and phosphate ion concentration. Dentiplus® lozenges and Remin Pro® -mousse include these components and may have a positive effect on remineralization process. The study investigated if using these additional agents for a month improves dental remineralization compared to tooth brushing using fluoride tooth paste alone. Methods: Twenty-two patients were included in the final study and all participants had initial caries lesions. They were randomly divided into two test groups (A and B) and a control group. All groups brushed their teeth twice a day with a toothpaste (1500 ppm fluoride). In addition, patients in group A used Dentiplus® -lozenges three times a day and patients in group B used Remin Pro®-mousse once a week. The patients in the control group only brushed their teeth. Lesions were diagnosed by using ICDAS classification, Nyvad’s modified criteria and DIAGNOdent-Pen® scanning. Results: One third of the lesions in incisors/canines became inactive in both intervention groups, whereas in the control group the respective figure was 15.6%. There was a decrease in LF values in the Dentiplus® group whereas in Remin Pro® group the change was controversial in other except the 1st molar teeth. Both decrease and increase of the LF values was seen in the control group. There were only minor changes as for ICDAS values in this study. Conclusion: Remineralization of initial lesions by tooth brushing alone can be improved by remineralizing agents especially lozenges rich in calcium and phosphate used regularly. Laser fluorescence is excellent in monitoring change n remineralization with short monitoring periods.

scholarly journals Methods of Non-Invasive In Vivo Optical Diagnostics in the Assessment of Structural Changes in the Skin Induced by Ultraviolet Exposure in an Experimental Model

Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1464
Author(s):  
Dmitry Kulikov ◽  
Mikhail Makmatov-Rys ◽  
Irina Raznitsyna ◽  
Polina Glazkova ◽  
Anastasiia Gerzhik ◽  
...  
Keyword(s):  
Uv Radiation ◽  
Colorimetric Assay ◽  
Diagnostic Methods ◽  
Laser Fluorescence ◽  
Optical Methods ◽  
Uv Exposure ◽  
Control Group ◽  
Doppler Flowmetry ◽  
Acute And Chronic Exposure

Background: This paper demonstrates the use of optical diagnostic methods to assess the dynamic skin changes observed in acute and chronic exposure to ultraviolet (UV) radiation in vivo. Methods: Firstly, in order to initiate photoaging (chronic UV exposure), animals (n = 40) were divided into two groups: chronic UV exposure (n = 30), and control (n = 10; without irradiation). Photoaging in animals was induced by chronic repeated exposure to UVA radiation three times per week, for 12 weeks continuously, while the UV dose increased stepwise over the course of the experiment (55 minimal erythema doses (MED) in total). Laser fluorescence spectroscopy (LFS), optical tissue oximetry (OTO), laser Doppler flowmetry (LDF), and optical coherence tomography (OCT) of the shaved dorsum skin were performed regularly, once per week until the conclusion of the study. At 0, 5, and 12 weeks of the experiment, histological examination of animal tissues using hematoxylin/eosin and Masson’s trichrome staining was performed. At the second stage, erythema was induced in mice (n = 15) by acute UV exposure at high doses. The colorimetric assay of the image from a digital RGB camera was used to evaluate the erythema index. Results: The tissue content index ηcollagen of collagen was appropriate for the characterization of skin photoaging. Significant differences (p < 0.05) in ηcollagen were found between the control and photoaging groups from the 5th to the 9th week of the experiment. In addition, the rate of collagen degradation in the control group was about half that of the photoaging group. This marker allows the differentiation of photo- and chronoaging. OCT revealed the main optical layers of the skin in compliance with the histological pattern. The analysis of the RGB camera images provided visualization of the acute skin reaction to UV radiation. Conclusions: This study demonstrates the applicability of optical methods for the quantitative assessment of acute and chronic skin effects of UV exposure in vivo.

Performance of a Pen-Type Laser Fluorescence Device and Conventional Methods in Detecting Approximal Caries Lesions in Primary Teeth – in vivo Study

2009 ◽  
Vol 43 (1) ◽  
pp. 36-42 ◽  
Author(s):  
T.F. Novaes ◽  
R. Matos ◽  
M.M. Braga ◽  
J.C.P. Imparato ◽  
D.P. Raggio ◽  
...  
Keyword(s):  
Primary Teeth ◽  
Laser Fluorescence ◽  
In Vivo Study ◽  
Conventional Methods ◽  
Caries Lesions ◽  
Approximal Caries

Multi-mode light microscopy of microtubule assembly dynamics and chromosome movement in vivo and In vitro

1996 ◽  
Vol 54 ◽  
pp. 730-731
Author(s):  
E. D. Salmon ◽  
J. C. Waters ◽  
C. Waterman-Storer
Keyword(s):  
Imaging System ◽  
Ccd Camera ◽  
Transmitted Light ◽  
Microtubule Assembly ◽  
Live Cells ◽  
Optical Efficiency ◽  
Multiple Band ◽  
Multi Mode

We have developed a multi-mode digital imaging system which acquires images with a cooled CCD camera (Figure 1). A multiple band pass dichromatic mirror and robotically controlled filter wheels provide wavelength selection for epi-fluorescence. Shutters select illumination either by epi-fluorescence or by transmitted light for phase contrast or DIC. Many of our experiments involve investigations of spindle assembly dynamics and chromosome movements in live cells or unfixed reconstituted preparations in vitro in which photodamage and phototoxicity are major concerns. As a consequence, a major factor in the design was optical efficiency: achieving the highest image quality with the least number of illumination photons. This principle applies to both epi-fluorescence and transmitted light imaging modes. In living cells and extracts, microtubules are visualized using X-rhodamine labeled tubulin. Photoactivation of C2CF-fluorescein labeled tubulin is used to locally mark microtubules in studies of microtubule dynamics and translocation. Chromosomes are labeled with DAPI or Hoechst DNA intercalating dyes.

Development of a bio-monitoring system for toxicants in water with fish

2001 ◽  
Vol 1 (2) ◽  
pp. 9-17
Author(s):  
Y.-H. Lee ◽  
H.-K. Lee ◽  
C.-H. Chang ◽  
W.-H. Kim
Keyword(s):  
Monitoring System ◽  
Treatment Plant ◽  
Ccd Camera ◽  
Water Treatment Plant ◽  
Abnormal Behavior ◽  
Time Interval ◽  
Toxic Substances ◽  
Bio Monitoring ◽  
Index Value ◽  
A Charge

A bio-monitoring system for toxicants in water has been developed and verified for actual applications. This system is based on the motionality of five Acheilognathus lanceolata, a fish known to be very sensitive to toxic substances, moving around in an aquarium. Their movements are continuously monitored with a charge coupled device (CCD) camera and analyzed to find and quantify any abnormal behavior in their motional characteristics in comparison with the pre-acquired data. That is, the images of fish captured by a CCD camera are digitalized to identify the location of fish in a constant time interval and the locations of each fish were then analyzed mathematically with a personal computer using the equations proposed to determine the motional characteristics such as floatness, fledness and mobility(agility). These data are then converted by means of fuzzy estimation to an index value, defined as the contamination index (CI), by which the system provides the information about the overall toxic strength of the toxicant in the water flowing into the aquarium. If the fish are exposed to toxicant(s), the CI value will be proportional to the strength of its toxicity. The pilot test was performed in a water treatment plant for six months in order to verify the reproducibility of the system over the unstable conditions such as highly turbid water after rainfall as well as in normal conditions. The test results revealed that this monitoring system has good reproducibility and sensitivity, proving our approach, described in this paper, is reliable. As a result, this approach seems to enable us to make a quick and easy detection of toxic substances contained in water, therefore, this system can be applied to a source of water supply as a toxicant watching system.

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