Objective: The purpose of this study was to evaluate the effect of the Yd:YAG laser irradiation on orthodontic bracket base surface. Shear bond strength (SBS) values and sites of the bonding failure interfaces were quantified.
Methods: Brackets were divided into two groups: OP (One Piece - integral sandblast base) and OPL (One Piece - laser irradiation). The brackets were randomly bonded on an intact enamel surface of 40 bovine incisors. The SBS tests were carry out using a universal test machine. A stereomicroscopy was used to evaluate the adhesive remnant index (ARI), and surface characterization was performed by scanning electron microscopy (SEM). Student's t-test was used to compare the SBS between the two groups (p< 0.05). Frequencies and chi-square analysis were applied to evaluate the ARI scores.
Results: OPL group showed higher value (p< 0.001) of SBS than OP group (43.95 MPa and 34.81 MPa, respectively). ARI showed significant difference (p< 0.001) between OPL group (ARI 0 = 100%) and OP group (ARI 0 = 15%). SEM showed a higher affinity between the adhesive and the irradiated laser base surface.
Conclusions: Yd:YAG laser irradiation on bracket base increased SBS values, showing that bonding failure occurs at the enamel/adhesive interface. Laser-etched bracket base may be used instead of conventional bases in cases where higher adhesion is required, reducing bracket-bonding failure.
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http://dx.doi.org/10.1590/2177-6709.25.1.028-035.oar | DOI Listing |
J Colloid Interface Sci
January 2025
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 China. Electronic address:
The tumor microenvironment (TME) is characterized by several key features, including hypoxia, elevated levels of hydrogen peroxide (HO), high concentrations of glutathione (GSH), and an acidic pH. Recent research has increasingly focused on harnessing or targeting these characteristics for effective cancer therapy. In this study, we developed an innovative composite bio-reactor that integrates genetically engineered bacteria with upconversion nanoparticles (UCNPs) and nano-copper manganese materials for lung cancer treatment.
View Article and Find Full Text PDFMol Pharm
January 2025
School of Pharmacy, Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226001, Jiangsu Province, China.
Photodynamic therapy (PDT) is increasingly regarded as an attractive approach for cancer treatment due to its advantages of low invasiveness, minimal side effects, and high efficiency. Here, two novel Ru(II) complexes , were designed and synthesized by coordinating phenanthroline and biquinoline ligands with Ru(II) center, and their chemo-photodynamic therapy and immunotherapy were explored. Both and exhibited significant phototoxicity against A549 and 4T1 tumor cells type-I/-II PDT.
View Article and Find Full Text PDFSci Rep
January 2025
Jilin Key Laboratory of Solid-State Laser Technology and Application, School of Science, Changchun, 130022, Jilin, China.
The response mechanism of a Four-Quadrant Photodetector (QPD) in an experimental setting was studied by irradiating a single QPD cell with a millisecond-pulsed laser. The response signal of the irradiated QPD cell varied with energy flux, pulse width, and applied bias, and comprised four main stages: an initial stage, decreasing barrier stage, holding stage, and recovery stage. Not only was the response signal of the irradiated cell affected by laser irradiation, but also the responses of the other three cells.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China. Electronic address:
Antibiotic resistance genes (ARGs) are markers of drug-resistant pathogens, monitoring them contributes to prevent resistance to drugs. The detection methods for ARGs including PCR and isothermal amplification are sensitive and selective. However, it may take several hours or cannot be used on spot.
View Article and Find Full Text PDFCurr Opin Otolaryngol Head Neck Surg
December 2024
Purpose Of Review: To summarize current evidence regarding the indication of adjuvant treatment after transoral laser microsurgery (TOLMS).
Recent Findings: Apart from well known risk factors, margins represent the key point in the decision-making. If margins are affected, additional treatment is mandatory.
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