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9 recordsLinked to original sources
PubMed2026

Effectiveness of high-power laser use in the removal of esthetic restorations: a systematic review.

This systematic review aimed to evaluate the effectiveness of high-power lasers in the removal of esthetic restorations compared with conventional methods. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and registered in PROSPERO (registration number: CRD420251055736). A comprehensive electronic search was performed in MEDLINE, Scopus, Embase, Web of Science, and the Cochrane Library. Study selection, data extraction, and methodological quality assessment were independently performed by four reviewers using QUIN tool for in vitro studies. A total of 2.384 records were identified, of which 19 in vitro studies conducted on extracted human permanent teeth met the eligibility criteria and were included in the qualitative synthesis. The included studies evaluated different high-power laser systems, predominantly Er: YAG and Er, Cr: YSGG lasers, as well as CO₂ lasers. Five studies were classified as high quality, whereas the remaining fourteen studies were classified as moderate quality. Available laboratory evidence suggests that laser-assisted techniques may represent a potential alternative approach for removing esthetic restorations, with advantages including conservative tissue removal, reduced damage to underlying tooth structures, and intrapulpal temperature increases within acceptable limits. The Er: YAG laser was the most frequently investigated system, with power settings ranging from 1.5 to 5.9 W, showing particularly favorable laboratorial performance in the removal of lithium disilicate restorations, especially in thinner substrates. Within the limitations of the available evidence, high-power lasers appear to be a promising and minimally invasive alternative to conventional methods for the removal of esthetic restorations. However, the predominance of in vitro studies highlights the need for well-designed clinical trials to confirm these findings and support their clinical application.

Humans↗
PubMed1979

[Method of determining the quality of irrigation of the vessels of parenchymatous organs before injection].

The method suggested for qualitative estimation of the renal and hepatic vessels perfusion before an injection is based on measuring oscillations of the light beam diffused by the organ's surface (the source--a gas laser of continuous action of red spectrum). An absolute photometer protected by a red filter from external effects of light is used as a registrator. Successive injection of the renal and hepatic vessels with different masses and their investigation by means of roentgenography, preparation, carrosion demonstrate a satisfactory effectiveness of the method presented.

Blood Vessels↗
PubMed2026

Topical Carboxytherapy as an Adjunct to Skin Recovery Post-CO2 Laser Fractional Resurfacing.

BACKGROUND: Topical carboxytherapy, a transcutaneous carbon dioxide (CO2) delivery system, may support skin repair and regeneration, yet its role as an adjunct to fractional laser treatment remains underexplored. OBJECTIVE: To investigate the effectiveness and safety of topical CO2 mask (CO2Lift® Carboxy Gel, Lumisque Skincare) in supporting skin recovery and improving clinical outcomes following fractional CO2 laser resurfacing. METHOD: This 12-week randomized, placebo-controlled trial evaluated mild-to-moderate photoaging (n=6 females only). Participants received either topical carboxytherapy (n=4) or standard care (n=2). Assessments included VISIA-CR imaging, biophysical measurements, investigator ratings, and paired (baseline and 4-week) skin biopsies. RESULTS: Topical carboxytherapy accelerated recovery and was well-tolerated, with no major adverse events. VISIA-CR imaging showed accelerated erythema resolution, transepidermal water loss normalized more rapidly, and pH remained stable. Skin histology at week 4 revealed epidermal thickening and rete ridge formation with topical carboxytherapy vs placebo. Investigator ratings demonstrated significantly improved healing, global assessment, and global aesthetic improvement scale scores, with trends toward improvement in photodamage, rhytides, and pigmentation. CONCLUSION: Adjunctive topical carboxytherapy after fractional CO2 resurfacing accelerated healing, improved barrier recovery, and overall aesthetic outcomes. Larger studies are needed to confirm these findings.

Humans↗
PubMed2026

Towards time-resolved MicroED grid preparation using mix-and-inject gas dynamic virtual nozzles.

Recent progress in gas dynamic virtual nozzle (GDVN) technologies in combination with high-brilliance synchrotron and X-ray free-electron lasers (XFELs) has allowed the visualization of protein dynamics in crystallo by mixing macromolecular protein crystals with a substrate using tunable mixing times on the order of milliseconds to seconds prior to serial X-ray diffraction data collection. This has become the method of choice for high-resolution structure determination of intermediate states. However, such experiments require large counts of crystals of proper sizes for high-resolution data collection, and premium beam times for screening efforts. Cryogenic microcrystal electron diffraction (MicroED) represents a complementary technique that may be a more accessible avenue for time-resolved nanocrystallography compared with serial X-ray diffraction experiments. MicroED can produce full diffraction datasets from just a few submicrometre-thick crystals, and the approach is more readily accessible, requiring standard cryogenic transmission electron microscopy (TEM) equipment available at many universities and institutes. Cryogenic MicroED, like other forms of cryo-EM, begins with rapidly freezing biological material on electron microscopy grids. In the case of MicroED, micro- to nano-crystals (<500&#x2005;nm thick) are deposited onto electron microscopy grids and plunge-frozen for subsequent electron diffraction data collection. Here, we have incorporated GDVN technology developed originally for XFEL experiments into the freezing process as a first step towards time-resolved studies. We describe the limited deposition efficiency of the model MicroED protein proteinase K on TEM grids using GDVNs, preceding sample vitrification and successful MicroED data collection. We discuss both the initial results from such experiments and the methodological challenges in developing this approach into a reliable workflow for millisecond-to-second time-resolved structural studies of macromolecules. Our results promise a strategy to deposit crystals on grids using GDVNs and determine high-resolution structures by MicroED, constituting a first step towards development of time-resolved MicroED experiments.

MicroED↗
PubMed1979

Micropreparation techniques in quantitative histochemistry - density gradient centrifugation, manual microdissection and laser microbeam preparation of tissue.

Each quantitative histochemical problem needs its specific method for tissue preparation. In this connection two of the most important preparation methods, density gradient centrifugation and microdissection of freeze-dried tissue slices, are described. Density gradient centrifugation is a very effective procedure for preparative separation of cell particles such as cell nuclei. The details of the preparation of glial and neuronal cell nuclei are described. The in vitro phosphorylation of histone in the chromatin in relation to age is given as a practical example of the quantitative histochemical application to a preparation of cell nuclei. Other techniques of tissue preparation are the manual tissue microdissection according to Lowry and the Laser microbeam preparation. Advantages and disadvantages of both methods are compared. It is shown, that the introduction of Laser microbeam dissection technique, as alternative to manual microdissection, add new dimensions to Lowry's ultramicrochemical methods. One has greater freedom in the choice of the sample size and the number of samples dissected from the same slice. Furthermore, the need for a well-trained person for the preparation is eliminated. The preparation is also considerably less time consuming and easier to perform than the manual free hand preparation. Two quantitative histochemical methods used for the investigation of microdissected tissue samples are described: the gas-chromatography-massfragmentography (GC/MS)-method for determination of transmitters and its metabolites as well as the enzymatic cycling technique of Lowry. The GC/MS-method is explained with an example of noradrenaline and dopamine determination. The enzymatic cycling technique is demonstrated in combination with the Oil-Well-Technique for determination of the NADP-cycle.

Cell Fractionation↗