scholarly journals Confocal laser scanning reflection microscopy applied to the remineralization studies in incipient caries lesions

2021 ◽  
Vol 2 (4) ◽  
pp. 489-503
Author(s):  
Betina R. Tolcachir ◽  
Carlos Mas ◽  
Juan Caselles ◽  
Arnaldo Mangeaud ◽  
Raquel V. Gallará

To evaluate through roughness parameters measurement the penetration of calcium phosphate stabilized by casein phosphopeptides (CPP-ACP) in the subsurface zone of the incipient caries lesions known in dentistry as white spot lesion (WSL). To our knowledge, there is no data about roughness parameters to evaluate the demineralization-remineralization process in the body of the lesion. WSL was generated in vitro in 10 dental samples and sectioned in half of them (longitudinal section). CPP-ACP was applied on the WSL (3 minutes daily for 60 days). Roughness parameters (Rp and Ra) were measured on the longitudinal section with a laser scanning confocal microscope in the reflection acquisition mode (CLSRM), either in the WSL or sound enamel, before and after applying CPP-ACP. CLSRM is a non-contact method able to detect small irregularities more precisely due to the small spot of laser illumination (0.5 μm).  Mixed linear models were carried out, using the treatment as a fixed factor and the tooth as a random factor (significance level 5%). Rp and Ra values in WSL area before applying the remineralization protocol (WSL pre) were significantly higher than in the sound enamel of the same samples. After applying CPP-ACP, Rp and Ra values decreased significantly with respect to the WSL pre and were similar to the values of these parameters in sound enamel. roughness parameters were used as an indirect way to measure the porosity of WSL at subsurface level. The decrease of these parameters could be interpreted as the remineralization of WSL by the ability of CPP-ACP to penetrate the body of the lesion. Clinical significance: WSL is characterized by the loss of minerals from the enamel and an increase in porosity at the subsurface level. The effectiveness of remineralizing substances would be determined by their ability to penetrate the body of the lesion and reduce porosity.

2012 ◽  
Vol 13 (4) ◽  
pp. 425-430 ◽  
Author(s):  
Shiny Benjamin ◽  
Roshni LNU ◽  
Sabeena Susan Thomas ◽  
Mohan Thomas Nainan

ABSTRACT Objective Remineralization is an effective treatment that may stop or reverse early tooth decay. Grape seed extract (GSE) is the potential remineralizing agent under investigation. Materials and methods Sound human tooth sections were obtained from the cervical portion of the root and stored in demineralizing solution at 37°C for 96 hours to induce artificial root caries lesions. The sections were divided into four treatment groups including 6.5% grape seed extract, sodium monofluorophosphate (220 ppm) with 0.05% calcium glycerophosphate, 0.5% calcium glycerophosphate and control (no treatment). An in vitro pH cycling model was used to cycle the demineralized specimens through treatment solutions, acidic buffer and neutral buffer for 8 days at 6 cycles per day. Subsequently, they were evaluated using confocal laser scanning microscope. Data were analyzed using analysis of variance (p < 0.05). Results GSE revealed less demineralization and more remineralization compared with other groups. Conclusion GSE promotes remineralization of artificial root caries lesions. Clinical significance The search for the perfect remineralizing agent continues to this day. GSE could be a welcome addition to the remineralization armamentarium. Abbreviations and acronyms GSE: Grape seed extract; ppm: Parts per million; CaGP: Calcium glycerophosphate; CLSM: Confocal laser scanning microscope; ANOVA: Analysis of variance; PA: Proanthocyanidin; CEJ: Cementoenamel junction; mM: Millimole; CaCl2.2H2O: Calcium chloride dihydrate; KH2PO4: Potassium dehydrate phosphate; K2HPO4: Dipotassium phosphate; dH2O: Deionized water; w/v: Weight by volume; ROD: Relative optical density; nm: Nanometer; SD: Standard deviation. How to cite this article Benjamin S, Roshni, Thomas SS, Nainan MT. Grape Seed Extract as a Potential Remineralizing Agent: A Comparative in vitro Study. J Contemp Dent Pract 2012;13(4):425-430.


2016 ◽  
Vol 83 (6) ◽  
Author(s):  
Yibo Zou ◽  
Markus Kästner ◽  
Eduard Reithmeier

AbstractIn this article, fractal analysis combined with roughness measurement is proposed to characterize the new generations of HVOF sprayed coatings' surface textures. Two-dimensional and three-dimensional box counting algorithms are introduced to determine the fractal dimension, which is considered as a scale-invariant parameter and is able to describe chaos and complexity of the surface. For surface roughness metrology, a confocal laser scanning microscope with different lenses is used to acquire the areal topography, providing a sequence of height maps with different image resolutions. Typical areal roughness parameters are assessed based on the international standard ISO-25178. The results show that the fractal dimension is a powerful tool to depict the nature of the surface texture of the investigated coatings. Moreover, it is found that the traditional amplitude roughness parameters depend strongly on the range of the measurement field as well as the datasets' resolution, whereas the fractal dimension is rather invariant to the scales of the measured datasets. Finally, the correlation between the fractal dimension and roughness parameters is given at the end of this paper.


Author(s):  
Sthefane D'ávila ◽  
Pedro Paulo de Abreu Manso ◽  
Elizabeth Cristina de Almeida Bessa ◽  
Maria de Lurdes de Azevedo Rodrigues

The aim of this study was to obtain data on the morphology and morphometry of pre-ovigerous and post-ovigerous adults of the species Tanaisia (Paratanaisia) bragai, using confocal laser scanning microscopy to obtain tomographic images of the suckers and tegument. For morphometric analysis, 45 specimens (30 pre-ovigerous adults and 15 post-ovigerous adults) were measured with the aid of an ocular micrometer coupled to the objective of a photonic microscope. Pre-ovigerous and post-ovigerous adult individuals, stained with Mair carmalumen and mounted in permanent preparations, were analyzed by means of confocal laser scanning microscopy. Positive correlation was detected between the body length and ovary length of post-ovigerous adults (rs: 0.774; p<0.01), as well as between the body length and testes (rs: 0.604 and 0.659; p< 0.05), the body length and the length of uterus (rs: 0.839; p< 0,01) and between the ovary width and egg length (rs: 0.777; p<0.01). Morphological study of the pre-ovigerous adults demonstrated that the ovary and testes develop simultaneously before the development of the uterus and vitelline glands. The acetabulum was detected in pre-ovigerous adults stained with hematoxilin and observed using light microscopy. In these specimens, the acetabulum measured 36.7 ± 6.9 µm (25-50 µm) in width and 39.91 ± 6.8 µm (25-55 µm) in length. The acetabulum was not detected in post-ovigerous adults observed with light microscopy. However, this structure was detected using confocal miscrocopy. In the post-ovigerous specimens, the acetabulum presented a reduced size compared to the pre-ovigerous adults. This may imply that this structure has more functional significance in the larval and pre-ovigerous stages.


2017 ◽  
Vol 28 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Michelle Alexandra Chinelatti ◽  
Camila Tirapelli ◽  
Silmara Aparecida Milori Corona ◽  
Renato Goulart Jasinevicius ◽  
Oscar Peitl ◽  
...  

Abstract This study evaluated the effect of a bioactive glass ceramic for the control of erosion and caries lesions. Fragments (n=10) of bovine enamel and root dentin received daily application of different treatments (Biosilicate; Acidulated Phosphate Fluoride- APF; Untreated - control) during the performance of erosive cycles. Surfaces were analyzed with 3D optical profilometry to quantify the superficial loss in four periods (1, 7, 14 and 21 days), as well as the lesion depth with confocal laser scanning microscopy. For caries progression assessment, initial Knoop microhardness was measured on enamel bovine fragments. Initial carious lesions were developed and specimens were divided into three groups (n=10), according to the daily topical application (Biosilicate; APF; no application - control), during the de-remineralization cycles for 14 days. Final microhardness was obtained to calculate the change of surface microhardness. Subsurface demineralization was analyzed using cross-sectional microhardness (depths 10, 30, 50, 70, 90, 110 and 220 µm). Data were tested using ANOVA and Tukey’s test (a=5%). Results of erosive evaluation showed that Biosilicate promoted the lowest (p<0.05) values of surface loss, regardless of time, for both enamel and dentin; APF promoted lower (p<0.05) surface loss than control; analyzing different periods of time, APF did not show difference (p>0.05) between 14 and 21 days of demineralization. Results of enamel caries assessment showed that Biosilicate resulted in higher (p<0.05) surface and subsurface microhardness than both APF and control-applications. It may be concluded that Biosilicate application showed a higher potential to reduce surface loss and development of erosion and caries lesions.


2021 ◽  
Vol 21 (4) ◽  
pp. 99-111
Author(s):  
Monika Górnik ◽  
Ewa Jonda ◽  
Monika Nowakowska ◽  
Leszek Łatka

Abstract The paper presents the computational studies on the microstructure of WC-Co-Cr coatings deposited by High Velocity Oxy Fuel spraying (HVOF). The study covers the porosity assessment according to ASTM E2109-01 standard, carried out in ImageJ software, in terms of volume porosity, size and shape of the pores. The evaluation was preceded by scanning electron microscope (SEM) observations at magnifications of 2000x and 5000x. Additionally, topography analysis has been performed by confocal laser scanning microscope (CLSM), and the surface roughness Ra was evaluated by the contact method with use of a stylus profilometer. Finally, the influence of porosity was observed for coatings microhardness HV0.3. According to the results, the total closed porosity was found to be in the range of 5.01 vol.% and 5.38 vol.%. The dominated pores in the coatings were of size 0.1-1.0 μm. Studies showed that HVOF process enabled deposition of dense coatings, characterized by homogenous distribution of pores and low roughness.


Author(s):  
Meghan Shilling ◽  
Lipiin Sung ◽  
Thomas R. Kurfess

In many mesoscale parts (&gt; 100μm) with microscale features (100nm to 100μm), the edge can constitute a large percentage of the total feature size. These edges need to be measured and characterized. Unfortunately, very few tools exist that are able to measure a range of angles with a resolution appropriate to these parts. The measurement methods commonly used to characterize mesoscale parts are designed for nominally planar surfaces and fail when used on a surface with moderate slope. Other tools exist which can adequately capture a sloping surface, however they have characteristics which make them less desirable for edge measurement (contact, destructive, image-output). The confocal laser scanning microscope (CLSM) is a non-contact method which has special properties that allow it to measure sloping surfaces of various materials and finishes. This paper will discuss the CLSM and its ability to measure edges of mesoscale parts.


2012 ◽  
Vol 23 (2) ◽  
pp. 110-115 ◽  
Author(s):  
Sandrine Bittencourt Berger ◽  
Sabrina Pavan ◽  
Paulo Henrique dos Santos ◽  
Marcelo Giannini ◽  
Ana Karina B. Bedran-Russo

The aim of this study was to evaluate effect of bleaching agents on sound enamel (SE) and enamel with early artificial caries lesions (CL) using confocal laser scanning microscopy (CLSM). Eighty blocks (4 x 5 x 5 mm) of bovine enamel were used and half of them were submitted to a pH cycling model to induce CL. Eight experimental groups were obtained from the treatments and mineralization level of the enamel (SE or CL) (n=10). SE groups: G1 - unbleached (control); G2 - 4% hydrogen peroxide (4 HP); G3 - 4 HP containing 0.05% Ca (Ca); G4 - 7.5% hydrogen peroxide (7.5 HP) containing amorphous calcium phosphate (ACP). CL groups: G5 - unbleached; G6 - 4 HP; G7 - 4 HP containing Ca; G8 - 7.5 HP ACP. G2, G3, G6, G7 were treated with the bleaching agents for 8 h/day during 14 days, while G4 and G8 were exposed to the bleaching agents for 30 min twice a day during 14 days. The enamel blocks were stained with 0.1 mM rhodamine B solution and the demineralization was quantified using fluorescence intensity detected by CLSM. Data were analyzed using ANOVA and Fisher’s tests (α=0.05). For the SE groups, the bleaching treatments increased significantly the demineralization area when compared with the unbleached group. In the CL groups, no statistically significant difference was observed (p>0.05).The addition of ACP or Ca in the composition of the whitening products did not overcome the effects caused by bleaching treatments on SE and neither was able to promote remineralization of CL.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Kohei Tahara ◽  
Shiho Fujimoto ◽  
Fumihiko Fujii ◽  
Yuichi Tozuka ◽  
Takashi Jin ◽  
...  

We have developed submicron-sized liposomes modified with a mucoadhesive polymer to enhance peptide drug absorption after oral administration. Liposomal behavior in the gastrointestinal tract is a critical factor for effective peptide drug delivery. The purpose of this study was to prepare quantum dot- (QD-) loaded submicron-sized liposomes and examine liposomal behavior in the body after oral administration using in vivo fluorescence imaging. Two types of CdSe/CdZnS QDs with different surface properties were used: hydrophobic (unmodified) QDs and hydrophilic QDs with glutathione (GSH) surface modifications. QD- and GSH-QD-loaded liposomes were prepared by a thin film hydration method. Transmission electron microscopy revealed that QDs were embedded in the liposomal lipid bilayer. Conversely, GSH-QDs were present in the inner aqueous phase. Some of the GSH-QDs were electrostatically associated with the lipid membrane of stearylamine-bearing cationic liposomes. QD-loaded liposomes were detected in Caco-2 cells after exposure to the liposomes, and these liposomes were not toxic to the Caco-2 cells. Furthermore, we evaluated the in vivo bioadhesion and intestinal penetration of orally administered QD-loaded liposomes by observing the intestinal segment using confocal laser scanning microscopy.


1990 ◽  
Vol 111 (6) ◽  
pp. 2463-2473 ◽  
Author(s):  
A Draeger ◽  
W B Amos ◽  
M Ikebe ◽  
J V Small

Confocal laser scanning microscopy of isolated and antibody-labeled avian gizzard smooth muscle cells has revealed the global organization of the contractile and cytoskeletal elements. The cytoskeleton, marked by antibodies to desmin and filamin is composed of a mainly longitudinal, meandering and branched system of fibrils that contrasts with the plait-like, interdigitating arrangement of linear fibrils of the contractile apparatus, labeled with antibodies to myosin and tropomyosin. Although desmin and filamin were colocalized in the body of the cell, filamin antibodies labeled additionally the vinculin-containing surface plaques. In confocal optical sections the contractile fibrils showed a continuous label for myosin for at least 5 microns along their length: there was no obvious or regular interruption of label as might be expected for registered myosin filaments. The cytoplasmic dense bodies, labeled with antibodies to alpha-actinin exhibited a regular, diagonal arrangement in both extended cells and in cells shortened in solution to one-fifth of their extended length: after the same shortening, the fibrils of the cytoskeleton that showed colocalization with the dense bodies in extended cells became crumpled and disordered. It is concluded that the dense bodies serve as coupling elements between the cytoskeletal and contractile systems. After extraction with Triton X-100, isolated cells bound so firmly to a glass substrate that they were unable to shorten as a whole when exposed to exogenous Mg ATP. Instead, they contracted internally, producing integral of 10 regularly spaced contraction nodes along their length. On the basis of differences of actin distribution two types of nodes could be distinguished: actin-positive nodes, in which actin straddled the node, and actin-negative nodes, characterized by an actin-free center flanked by actin fringes of 4.5 microns minimum length on either side. Myosin was concentrated in the center of the node in both cases. The differences in node morphology could be correlated with different degrees of coupling of the contractile with the cytoskeletal elements, effected by a preparation-dependent variability of proteolysis of the cells. The nodes were shown to be closely related to the supercontracted cell fragments shown in the accompanying paper (Small et al., 1990) and furnished further evidence for long actin filaments in smooth muscle. Further, the segmentation of the contractile elements pointed to a hierarchial organization of the myofilaments governed by as yet undetected elements.


Author(s):  
Thomas M. Jovin ◽  
Michel Robert-Nicoud ◽  
Donna J. Arndt-Jovin ◽  
Thorsten Schormann

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.


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