Репозиторий Университета

The development of laser medicine has led to its use in dentistry further to improve existing treatment methods, including surgical techniques. The variety of lasers allows them to be used for procedures on the soft and bone tissues of the oral cavity as well as on the tissues of the teeth. The short duration of laser pulse action on tissues, selective action on pathological tissues in a sterile surgical field, and activation of local and humoral immunity of the oral cavity provides an increase in the regeneration potential of tissues of the postoperative area, which contributes to the shortening of wound process phases, favorable course of the postoperative period, and shortening of the healing time. Our article presents the experience of using the Nd:YAG laser in different modes in replicating the effect of curettage of periodontal pockets in an experiment on laboratory animals. According to the study results, there was a difference in the healing time of soft tissues after their exposure to several modes of the Nd:YAG laser, which makes it possible to recommend each of them for individual clinical cases.

© 2020, Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature. One dimensional (1D) nanostructures attract considerable attention, enabling a broad application owing to their unique properties. However, the precise mechanism of 1D morphology attainment remains a matter of debate. In this study, ultrafast picosecond (ps) laser-induced treatment on upconversion nanoparticles (UCNPs) is offered as a tool for 1D-nanostructures formation. Fragmentation, reshaping through recrystallization process and bioadaptation of initially hydrophobic (β-Na1.5Y1.5F6: Yb3+, Tm3+/β-Na1.5Y1.5F6) core/shell nanoparticles by means of one-step laser treatment in water are demonstrated. “True” 1D nanostructures through “Medusa”-like structures can be obtained, maintaining anti-Stokes luminescence functionalities. A matter of the one-dimensional UCNPs based on direction of energy migration processes is debated. The proposed laser treatment approach is suitable for fast UCNP surface modification and nano-to-nano transformation, that open unique opportunities to expand UCNP applications in industry and biomedicine. [Figure not available: see fulltext.].

© 2020 Elsevier Ltd A laser technology has been developed for fabricating structures from composite layers based on biopolymers: albumin, collagen, and chitosan with single-walled carbon nanotubes (SWCNT). The structures are intended for cardiovascular devices and tissue-engineered implants. This is evidenced by the results of studies. The composite layers were fabricated due to the phase transition of biopolymers and SWCNT aqueous dispersion under the influence of laser pulses. At the same time branched 3D networks of SWCNT were formed in the biopolymer matrix. The threshold energy fluence of laser pulses was determined (0.032–0.083 J/cm2) at which a bimodal distribution of pores was observed. The calculation of contact resistances between nanotubes at percolation units of 3D networks (20–100 kOhm) was carried out. Composite layers fabricated by laser demonstrated conductivity values that were higher (12.4 S/m) than those for layers by thermostat (4.7 S/m). The maximum hardness of the composite layers with SWCNT (0.01 wt%) by laser was 482 ± 10, 425 ± 10, and 407 ± 15 MPa for albumin, collagen and chitosan, respectively. The hardness of the thermostat layers was less than 100 MPa. The viability of endothelial cells in composite layers was improved. The composite layers ensured a normal level of hemolysis during interaction with erythrocytes.

© 2020 Elsevier B.V. Herein, the synthesis, design, and the physicochemical characterization of phosphorus functionalized thiazolotriazole (PFT) compound are presented. The PFT tests on the biological activity revealed butyrylcholinesterase inhibition that was confirmed and explained with molecular docking studies. The pronounced reduction of optical density and biological activity was found as a result of irradiation of the PFT water solution with laser beam at wavelength 266 nm. The observed phenomenon was explained on the base of molecular dynamics, docking, and density functional theory modeling by the formation of PFT conformers via laser-induced phosphonate group twisting. The reorganization of the PFT geometry was found to be a reason of butyrylcholinesterase inhibition mechanism change and the site-specificity loss. These results demonstrate that PFT combines photoswitching and bioactive properties in one molecule that makes it promising as a molecular basis for the further design of bioactive substances with photosensitive properties based on the mechanism of the phosphonate group phototwisting.

© 2020 Elsevier B.V. Photosensitive polymeric three-dimensional microstructured film (PTMF) is a new type of patterned polymeric films functionalized with an array of sealed hollow 3D containers. The microstructured system with enclosed chemicals provides a tool for the even distribution of biologically active substances on a given surface that can be deposited on medical implants or used as a cells substrate. In this work, we proposed a way for photothermally activating and releasing encapsulated substances at picogram amounts from the PTMF surface in different environments using laser radiation delivered with a multimode optical fiber. The photosensitive PTMFs were prepared by the layer-by-layer (LbL) assembly from alternatively charged polyelectrolytes followed by covering with a layer of hydrophobic polylactic acid (PLA) and a layer of gold nanoparticles (AuNPs). Moreover, the typical photothermal cargo release amounts were determined on the surface of the PTMF for a range of laser powers delivered to films placed in the air, deionized (DI) water, and 1% agarose gel. The agarose gel was used as a soft tissue model for developing a technique for the laser activation of PTMFs deep in tissues using optical waveguides. The number of PTMF chambers activated by a near-infrared (NIR) laser beam was evaluated as the function of optical parameters.

© 2020 Elsevier B.V. Photosensitive polymeric three-dimensional microstructured film (PTMF) is a new type of patterned polymeric films functionalized with an array of sealed hollow 3D containers. The microstructured system with enclosed chemicals provides a tool for the even distribution of biologically active substances on a given surface that can be deposited on medical implants or used as a cells substrate. In this work, we proposed a way for photothermally activating and releasing encapsulated substances at picogram amounts from the PTMF surface in different environments using laser radiation delivered with a multimode optical fiber. The photosensitive PTMFs were prepared by the layer-by-layer (LbL) assembly from alternatively charged polyelectrolytes followed by covering with a layer of hydrophobic polylactic acid (PLA) and a layer of gold nanoparticles (AuNPs). Moreover, the typical photothermal cargo release amounts were determined on the surface of the PTMF for a range of laser powers delivered to films placed in the air, deionized (DI) water, and 1% agarose gel. The agarose gel was used as a soft tissue model for developing a technique for the laser activation of PTMFs deep in tissues using optical waveguides. The number of PTMF chambers activated by a near-infrared (NIR) laser beam was evaluated as the function of optical parameters.

© 2020 Elsevier B.V. Photosensitive polymeric three-dimensional microstructured film (PTMF) is a new type of patterned polymeric films functionalized with an array of sealed hollow 3D containers. The microstructured system with enclosed chemicals provides a tool for the even distribution of biologically active substances on a given surface that can be deposited on medical implants or used as a cells substrate. In this work, we proposed a way for photothermally activating and releasing encapsulated substances at picogram amounts from the PTMF surface in different environments using laser radiation delivered with a multimode optical fiber. The photosensitive PTMFs were prepared by the layer-by-layer (LbL) assembly from alternatively charged polyelectrolytes followed by covering with a layer of hydrophobic polylactic acid (PLA) and a layer of gold nanoparticles (AuNPs). Moreover, the typical photothermal cargo release amounts were determined on the surface of the PTMF for a range of laser powers delivered to films placed in the air, deionized (DI) water, and 1% agarose gel. The agarose gel was used as a soft tissue model for developing a technique for the laser activation of PTMFs deep in tissues using optical waveguides. The number of PTMF chambers activated by a near-infrared (NIR) laser beam was evaluated as the function of optical parameters.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. Background: A large number of systemic diseases can be linked to oral candida pathogenicity. The global trend of invasive candidiasis has increased progressively and is often accentuated by increasing Candida albicans resistance to the most common antifungal medications. Photodynamic therapy (PDT) is a promising therapeutic approach for oral microbial infections. A new formulation of 5-aminolevulinic acid (5%ALA) in a thermosetting gel (t) (5%ALA-PTt) was patented and recently has become available on the market. However, its antimicrobial properties, whether mediated or not by PDT, are not yet known. In this work we characterised them. Methods: We isolated a strain of C. albicans from plaques on the oral mucus membrane of an infected patient. Colonies of this strain were exposed for 1 24 h, to 5%ALA-PTt, 5%ALA-PTt buffered to pH 6.5 (the pH of the oral mucosa) (5%ALA-PTtb) or not exposed (control). The 1 h-exposed samples were also irradiated at a wavelength of 630 nm with 0.14 watts (W) and 0.37 W/cm2 for 7 min at a distance of <1 mm. Results and conclusion: The 5% ALA-PTt preparation was shown to be effective in reducing the growth of biofilm and inoculum of C. albicans. This effect seems to be linked to the intrinsic characteristics of 5%ALA-TPt, such acidic pH and the induction of free radical production. This outcome was significantly enhanced by the effect of PDT at relatively short incubation and irradiation times, which resulted in growth inhibition of both treated biofilm and inoculum by ∼80% and ∼95%, respectively.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.