Nd-YAG QS laser cleaning of soiled stone at 1064 nm can sometimes result in a more yellow appearance compared to other cleaning techniques. Especially in France, this yellowing effect is still considered as a major aesthetic issue by the architects and conservators. One explanation states that the yellowing is linked to the formation of iron-rich nanophase(s) through the laser beam interaction with black crusts that would re-deposit on the cleaned substrate after irradiation. To characterize these nanophases, a model crust containing hematite was elaborated and laser irradiated using a Nd-YAG QS laser. The color of the sample shifted instantaneously from red to a bright yellow and numerous particles were ablated in a visible smoke. Transmission electron microscopy (TEM) was used to examine the morphology and the crystallinity of the neo-formed compounds, both on the surface of the samples and in the ablated materials. In addition, an investigation of the chemical and structural properties of the nanophases was conducted by X-ray dispersive energy (EDX) and electron energy loss (EELS) spectroscopies. It was found that both the surface of the sample and the ablated materials are covered by crystallized nano-spheres and nano-residues, all containing iron and oxygen, sometimes along with calcium and sulfur. In particular an interfacial area containing the four elements was evidenced between some nanostructures and the substrate. Magnetite FeO was also identified at the nanoscale. This study demonstrates that the laser yellowing of a model crust is linked to the presence of iron-rich nanophases including CaFeSO nanostructures and magnetite FeO at the surface after irradiation.
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http://dx.doi.org/10.1016/j.micron.2018.08.006 | DOI Listing |
Indian Dermatol Online J
December 2024
Department of Clinical Research, CUTIS Academy of Cutaneous Sciences, Bengaluru, Karnataka, India.
Background: Laser therapy has emerged as an innovative approach for managing various nail conditions, offering precise targeting, minimal invasiveness, and favorable safety profiles. This review analyzes the literature on laser therapy for nail indications, encompassing onychomycosis, nail psoriasis, nail warts, ingrown toenails, onychodystrophy, nail pigmentation disorders, and nail tumors.
Methods: PubMed and Google Scholar databases were searched to identify articles on laser therapy using specific key terms related to nail conditions (e.
Lasers Med Sci
January 2025
Universidade Federal de Pelotas, Pelotas, Brazil.
This systematic review aimed to compare postoperative pain in endodontic treatments using PIPS Er: YAG laser-activated irrigation (LAI) versus conventional needle irrigation. An electronic search was conducted to identify randomized clinical trials (RCT) investigating postoperative pain in patients who underwent root canal treatments in permanent teeth using PIPS Er: YAG laser-activated irrigation or conventional needle irrigation. Two reviewers performed study selection, data extraction, risk of bias assessment (RoB 2.
View Article and Find Full Text PDFOral Maxillofac Surg
January 2025
North Cumbria University Hospitals NHS Trust, Carlisle, UK.
Introduction: Increasing emphasis has been placed on measurement of quality of life (QOL) as a central criterion for assessment of success of any medical treatment. The aim of our study was to assess the nutritional and quality of life of patient-reported outcomes among patients who have undergone laser resection of tongue cancer.
Materials And Methods: A cross-sectional study was undertaken of patients treated with KTP laser resection of T1/T2 tongue squamous cell carcinoma (SCC) between 2011-2019.
Front Aging Neurosci
January 2025
Department of Joint Surgery, Shandong Provincial Hospital, Shandong University, Jinan, Shandong, China.
Objectives: To perform a meta-analysis of previous studies investigating the effects of laser acupuncture on osteoarthritis.
Study Design: Systematic review and meta-analysis.
Methods: Randomized controlled trials (RCTS) on laser acupuncture for osteoarthritis were searched in the databases of PubMed, Embase, Cochrane Library, and Web of Science with a search deadline of 24 December 2023.
Lasers Med Sci
January 2025
Department of Dermatology, Beijing Friendship Hospital, Capital Medical University, Beijing, China.
Melasma significantly impacts life quality, and while various laser therapies show promise, rigorous comparative studies, especially between the novel Picosecond Alexandrite Laser (PSAL) and the traditional combined modality of Q-switched and Long-pulse Nd: YAG Lasers (QLNYL), are notably lacking. This study aims to fill this gap by evaluating the efficacy and safety of these modalities, providing insights into their comparative advantages for clinical practice. In a prospective, evaluator-blinded study, 40 participants with Fitzpatrick Skin Types (FST) III and IV underwent three treatment sessions at four-week intervals with either PSAL or QLNYL.
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