scholarly journals Design and manufacture of a device using transillumination and scattering near-infrared techniques for detecting dental lesions

10.29007/pj2r ◽  
2020 ◽  
Author(s):  
Thi Hai Mien Pham ◽  
Khac Thinh Nguyen ◽  
Phuoc An Truong Thi ◽  
My Nhat Truong Thi ◽  
Minh Huong Nguyen Thi
Keyword(s):  
Ionizing Radiation ◽  
Near Infrared ◽  
X Rays ◽  
Diagnostic Device ◽  
Dental Tissue ◽  
Nir Light ◽  
Demineralized Enamel ◽  
Design And Manufacture ◽  
Dental Lesions ◽  
Infrared Techniques

In dentistry, near-infrared (NIR) technology has been studied for decades that is being applied for the detection of dental damages without using ionizing radiation. Based on the interaction between dental tissue and NIR light such as transmission, absorption, and scattering, the teeth structure, and dental lesions can be observed by NIR images. The aim of this study was to build the dental diagnostic device using NIR light at 850-nm wavelength for detecting the early and hidden dental damages, that are not observed by X-rays. According to the various types of teeth samples, the transillumination and the scattering methods were designed and applied for capturing the teeth structures. The transillumination technique was used for thin teeth such as incisor and canine while the scattering system for observing the occlusal surface. The results show that the areas suspected to be the demineralized enamel are distinctly distinguished from the surrounding sound tissues and especially, the stain and pigmentation don’t appear in the NIR image. The designed device meets some requirements such as simple setup, safety, and affordable price for the purpose of replacement of imported equipment.

scholarly journals Assessment of the effectiveness of the NIR imaging systems applied to diagnose early dental lesions

10.29007/6nx7 ◽  
2020 ◽  
Author(s):  
Thi Hai Mien Pham ◽  
Manh Cuong Hoang ◽  
My Nhat Truong Thi ◽  
Khac Thinh Nguyen ◽  
Phuoc An Truong Thi
Keyword(s):  
Near Infrared ◽  
Early Stage ◽  
Imaging Systems ◽  
X Rays ◽  
Clinical Method ◽  
Nir Light ◽  
Nir Imaging ◽  
White Spots ◽  
Combination Of Methods ◽  
Dental Lesions

In recent years, oral problems are receiving more attention from not only experts but also almost people. If tooth lesions in the early stages, such as white spots, hidden dental caries, and tooth decay, etc., are not detected and treated promptly, they will lead to a risk of tooth loss. There are several common methods to detect tooth lesions such as clinical method, X-rays, and particularly near-infrared method, which is being developed significantly during the past decades. This method is substantially efficient for detecting early lesions by observing infrared images of tooth structures. In this study, near-infrared (NIR) light at 850 nm was used for detecting dental lesions. Enamel is nearly translucent in NIR light, so the lesions located under the enamel layer can be observed due to the interaction between NIR light and demineralized lesions. In addition, the NIR method is not only a safe method but also able to detect dental lesions at the early stage and tooth cracks which X-rays are limited to detect. In dentistry, an accurate diagnosis requires a combination of methods. Nowadays, X-rays are not only the common method but also the gold standard in dentistry, so this study incorporated clinical evaluation and X-rays to make the criteria for dental lesion diagnosis. This article has aimed to analyze and evaluate the effectiveness of the NIR imaging systems in detecting dental lesions and compare the NIR method to the clinical method combined with X-rays by Cohen's Kappa coefficient using SPSS (Statistical Package for the Social Sciences).

scholarly journals An in vitro of radiation dose enhancement using gold nanorods and plasmonic photothermal therapy

2021 ◽  
Author(s):  
Daniel DiCenzo DiCenzo
Keyword(s):  
Radiation Dose ◽  
Ionizing Radiation ◽  
Gold Nanorods ◽  
Near Infrared ◽  
Infrared Light ◽  
Nuclear Localization Sequence ◽  
X Rays ◽  
Dose Enhancement ◽  
Near Infrared Light ◽  
Pc3 Cells

Gold nanoparticles (GNP) have been shown to highly absorb ionizing radiation compared to tissue. GNPs have also been shown to be high absorbers of non-ionizing radiation with a peak absorbance at a wavelength dependent on their shape and size. This study investigated radiation dose enhancement in PC3 cells when in the presence of gold nanorods (NR) and near infrared light (IR). The PC3 cells were incubated with either PEGylated NRs (PNR) or anti prostate stem cell antigen antibody with nuclear localization sequence peptide conjugated NRs (AbNR). They were exposed to near infrared light at a wavelength of 810 nm to achieve a temperature of 42 ºC to 43 ºC for 60 minutes. They were also exposed to 160 kVp x-rays. It was found that both targeted and non-targeted GNPs when exposed to radiation and near infrared light synergistically enhanced radiation dose. It was also found that AbNRs provide greater dose enhancement than PNRs.

scholarly journals Early stage dental caries detection using near infrared spatial frequency domain imaging

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alistair D. Bounds ◽  
John M. Girkin
Keyword(s):  
Dental Caries ◽  
Spatial Frequency ◽  
Frequency Domain ◽  
Near Infrared ◽  
Early Stage ◽  
Infrared Light ◽  
Dental Tissue ◽  
Spatial Frequency Domain Imaging ◽  
Demineralized Enamel ◽  
Spatial Frequency Domain

AbstractEarly stage dental caries can be remineralized without the need for “drill-and-fill” treatments that are more invasive and less permanent. However, early stage caries lesions typically present as a white spot on a white background, resulting in many lesions only being identified after they have developed beyond the point of remineralization as cavities. We present a spatial frequency domain imaging technique to characterize the optical properties of dental tissue. This technique enables different dental tissue types (healthy enamel, healthy dentin and damaged or demineralized enamel) to be easily distinguished from one another and allows quantification of the reduced scattering coefficients of dental tissue. The use of near-infrared light at 850 nm allows high depth penetration into the tissue and suppression of absorption effects, ensuring only changes in the reduced scattering coefficient that result directly from demineralization of enamel are observed and simplifying the analysis method. This technique provides a tool to both guide the attention of dentists to areas of interest and potential demineralization, and to provide longitudinal quantified assessments to monitor caries lesion behaviour over time.

scholarly journals An in vitro of radiation dose enhancement using gold nanorods and plasmonic photothermal therapy

2021 ◽  
Author(s):  
Daniel DiCenzo DiCenzo
Keyword(s):  
Radiation Dose ◽  
Ionizing Radiation ◽  
Gold Nanorods ◽  
Near Infrared ◽  
Infrared Light ◽  
Nuclear Localization Sequence ◽  
X Rays ◽  
Dose Enhancement ◽  
Near Infrared Light ◽  
Pc3 Cells

Gold nanoparticles (GNP) have been shown to highly absorb ionizing radiation compared to tissue. GNPs have also been shown to be high absorbers of non-ionizing radiation with a peak absorbance at a wavelength dependent on their shape and size. This study investigated radiation dose enhancement in PC3 cells when in the presence of gold nanorods (NR) and near infrared light (IR). The PC3 cells were incubated with either PEGylated NRs (PNR) or anti prostate stem cell antigen antibody with nuclear localization sequence peptide conjugated NRs (AbNR). They were exposed to near infrared light at a wavelength of 810 nm to achieve a temperature of 42 ºC to 43 ºC for 60 minutes. They were also exposed to 160 kVp x-rays. It was found that both targeted and non-targeted GNPs when exposed to radiation and near infrared light synergistically enhanced radiation dose. It was also found that AbNRs provide greater dose enhancement than PNRs.

Catalyst Halogenation Enables Rapid and Efficient Polymerizations with Visible to Near-Infrared Light

2020 ◽  
Author(s):  
Alex Stafford ◽  
Dowon Ahn ◽  
Emily Raulerson ◽  
Kun-You Chung ◽  
Kaihong Sun ◽  
...  
Keyword(s):  
Near Infrared ◽  
Transient Absorption ◽  
Reaction Times ◽  
Infrared Light ◽  
Structure Property ◽  
Light Emitting ◽  
Structure Property Relationships ◽  
Nir Light ◽  
Light Intensities ◽  
Emission Quenching

Driving rapid polymerizations with visible to near-infrared (NIR) light will enable nascent technologies in the emerging fields of bio- and composite-printing. However, current photopolymerization strategies are limited by long reaction times, high light intensities, and/or large catalyst loadings. Improving efficiency remains elusive without a comprehensive, mechanistic evaluation of photocatalysis to better understand how composition relates to polymerization metrics. With this objective in mind, a series of methine- and aza-bridged boron dipyrromethene (BODIPY) derivatives were synthesized and systematically characterized to elucidate key structure-property relationships that facilitate efficient photopolymerization driven by visible to NIR light. For both BODIPY scaffolds, halogenation was shown as a general method to increase polymerization rate, quantitatively characterized using a custom real-time infrared spectroscopy setup. Furthermore, a combination of steady-state emission quenching experiments, electronic structure calculations, and ultrafast transient absorption revealed that efficient intersystem crossing to the lowest excited triplet state upon halogenation was a key mechanistic step to achieving rapid photopolymerization reactions. Unprecedented polymerization rates were achieved with extremely low light intensities (< 1 mW/cm<sup>2</sup>) and catalyst loadings (< 50 μM), exemplified by reaction completion within 60 seconds of irradiation using green, red, and NIR light-emitting diodes.

Bi19S27I3 nanorods: a new candidate for photothermal therapy in the first and second biological near-infrared windows

Nanoscale ◽  
2021 ◽  
Author(s):  
Jinsong Xiong ◽  
Qinghuan Bian ◽  
Shuijin Lei ◽  
Yatian Deng ◽  
Kehan Zhao ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Research Interest ◽  
The Past ◽  
Nir Light ◽  
Considerable Research ◽  
Key Factor

Near-infrared (NIR) light induced photothermal cancer therapy using nanomaterials as photothermal agents has attracted considerable research interest over the past few years. As the key factor in the photothermal therapy...

scholarly journals Differential Effects of Gold Nanoparticles and Ionizing Radiation on Cell Motility between Primary Human Colonic and Melanocytic Cells and Their Cancerous Counterparts

2021 ◽  
Vol 22 (3) ◽  
pp. 1418
Author(s):  
Elham Shahhoseini ◽  
Masao Nakayama ◽  
Terrence J. Piva ◽  
Moshi Geso
Keyword(s):  
Gold Nanoparticles ◽  
Ionizing Radiation ◽  
Cancer Cells ◽  
Cell Lines ◽  
Colorectal Adenocarcinoma ◽  
X Rays ◽  
Cell Adherence ◽  
Cancerous Cell ◽  
Primary Colon ◽  
Radiation Induced

This study examined the effects of gold nanoparticles (AuNPs) and/or ionizing radiation (IR) on the viability and motility of human primary colon epithelial (CCD841) and colorectal adenocarcinoma (SW48) cells as well as human primary epidermal melanocytes (HEM) and melanoma (MM418-C1) cells. AuNPs up to 4 mM had no effect on the viability of these cell lines. The viability of the cancer cells was ~60% following exposure to 5 Gy. Exposure to 5 Gy X-rays or 1 mM AuNPs showed the migration of the cancer cells ~85% that of untreated controls, while co-treatment with AuNPs and IR decreased migration to ~60%. In the non-cancerous cell lines gap closure was enhanced by ~15% following 1 mM AuNPs or 5 Gy treatment, while for co-treatment it was ~22% greater than that for the untreated controls. AuNPs had no effect on cell re-adhesion, while IR enhanced only the re-adhesion of the cancer cell lines but not their non-cancerous counterparts. The addition of AuNPs did not enhance cell adherence. This different reaction to AuNPs and IR in the cancer and normal cells can be attributed to radiation-induced adhesiveness and metabolic differences between tumour cells and their non-cancerous counterparts.

scholarly journals Near-Infrared-Triggered Upconverting Nanoparticles for Biomedicine Applications

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 756
Author(s):  
Manoj Kumar Mahata ◽  
Ranjit De ◽  
Kang Taek Lee
Keyword(s):  
Drug Delivery ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Cutting Edge ◽  
Clinical Translation ◽  
Basic Knowledge ◽  
Nanotechnology Research ◽  
Nir Light

Due to the unique properties of lanthanide-doped upconverting nanoparticles (UCNP) under near-infrared (NIR) light, the last decade has shown a sharp progress in their biomedicine applications. Advances in the techniques for polymer, dye, and bio-molecule conjugation on the surface of the nanoparticles has further expanded their dynamic opportunities for optogenetics, oncotherapy and bioimaging. In this account, considering the primary benefits such as the absence of photobleaching, photoblinking, and autofluorescence of UCNPs not only facilitate the construction of accurate, sensitive and multifunctional nanoprobes, but also improve therapeutic and diagnostic results. We introduce, with the basic knowledge of upconversion, unique properties of UCNPs and the mechanisms involved in photon upconversion and discuss how UCNPs can be implemented in biological practices. In this focused review, we categorize the applications of UCNP-based various strategies into the following domains: neuromodulation, immunotherapy, drug delivery, photodynamic and photothermal therapy, bioimaging and biosensing. Herein, we also discuss the current emerging bioapplications with cutting edge nano-/biointerfacing of UCNPs. Finally, this review provides concluding remarks on future opportunities and challenges on clinical translation of UCNPs-based nanotechnology research.

Biodegradable Nano-photosensitizer with Photoactivatable Singlet Oxygen Generation for Synergistic Phototherapy

2021 ◽  
Author(s):  
Jiaxin Shen ◽  
Dandan Chen ◽  
Ye Liu ◽  
Guoyang Gao ◽  
Zhihe Liu ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cancer Therapy ◽  
Singlet Oxygen ◽  
Near Infrared ◽  
Promising Method ◽  
Normal Cells ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
Nir Light

Photodynamic therapy (PDT) is a promising method for cancer therapy and also may initiate unexpected damages to normal cells and tissues. Herein, we developed a near-infrared (NIR) light-activatable nanophotosensitizer, which...

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