Optimizing Dental Bond Strength: Insights from Comprehensive Literature Review and Future Implications for Clinical Practice.

This review examines the modifying factors affecting bond strength in various bonding scenarios, particularly their relevance to the longevity of dental restorations. Understanding these factors is crucial for improving clinical outcomes in dentistry. Data were gathered from the PubMed database, ResearchGate, and Google Scholar resources, covering studies from 1992 to 2022. The findings suggest that for dentin-resin bonds, minimizing smear layers and utilizing MMP inhibitors to prevent hybrid layer degradation are essential. In the case of resin-resin bonds, reversing blood contamination is possible, but preventing saliva contamination is more challenging, underscoring its critical importance during clinical procedures. Additionally, while pretreatment on ceramics has minimal impact on bond strength, the influence of specific colorings should be carefully considered in treatment planning. This comprehensive review highlights that although established practices recognize significant bond strength factors, ongoing research provides valuable insights to enhance the clinical experience for patients. Once confirmed through rigorous experimentation, these emerging findings should be swiftly integrated into dental practice to improve patient outcomes.

Construction and Validation of Mortality Risk Nomograph Model for Severe/Critical Patients with COVID-19.

Objective: A nomograph model of mortality risk for patients with coronavirus disease 2019 (COVID-19) was established and validated. Methods: We collected the clinical medical records of patients with severe/critical COVID-19 admitted to the eastern campus of Renmin Hospital of Wuhan University from January 2020 to May 2020 and to the north campus of Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, from April 2022 to June 2022. We assigned 254 patients to the former group, which served as the training set, and 113 patients were assigned to the latter group, which served as the validation set. The least absolute shrinkage and selection operator (LASSO) and multivariable logistic regression were used to select the variables and build the mortality risk prediction model. Results: The nomogram model was constructed with four risk factors for patient mortality following severe/critical COVID-19 (≥3 basic diseases, APACHE II score, urea nitrogen (Urea), and lactic acid (Lac)) and two protective factors (percentage of lymphocyte (L%) and neutrophil-to-platelets ratio (NPR)). The area under the curve (AUC) of the training set was 0.880 (95% confidence interval (95%CI), 0.837~0.923) and the AUC of the validation set was 0.814 (95%CI, 0.705~0.923). The decision curve analysis (DCA) showed that the nomogram model had high clinical value. Conclusion: The nomogram model for predicting the death risk of patients with severe/critical COVID-19 showed good prediction performance, and may be helpful in making appropriate clinical decisions for high-risk patients.

Formation of gold decorated porphyrin nanoparticles and evaluation of their photothermal and photodynamic activity.

A core-shell gold (Au) nanoparticle with improved photosensitization have been successfully fabricated using Au nanoparticles and 5,10,15,20 tetrakis pentafluorophenyl)-21H,23H-porphine (PF6) dye, forming a dyad through molecular self-assembly. Au nanoparticles were decorated on the shell and PF6 was placed in the core of the nanoparticles. Highly stable Au nanoparticles were achieved using PF6 with poly(N-vinylcaprolactam-co-N-vinylimidazole)-g-poly(D,L-lactide) graft copolymer hybridization. This was compared with hybridization using cetyltrimethylammonium bromide and polyethylene glycol-b-poly(D,L-lactide) for shell formation with PF6-Au. The resulting PF6-poly(N-vinylcaprolactam-co-N-vinylimidazole)-g-poly(D,L-lactide)-Au core-shell nanoparticle were utilized for photothermal and photodynamic activities. The spectroscopic analysis and zeta potential values of micelles revealed the presence of a thin Au layer coated on the PF6 nanoparticle surface, which generally enhanced the thermal stability of the gold nanoparticles and the photothermal effect of the shell. The core-shell PF6-Au nanoparticles were avidly taken up by cells and demonstrated cellular phototoxicity upon irradiation with 300W halogen lamps. The structural arrangement of PF6 dyes in the core-shell particles assures the effectiveness of singlet oxygen production. The study verifies that PF6 particles when companied with Au nanoparticles as PF6-Au have possible combinational applications in photodynamic and photothermal therapies for cancer cells because of their high production of singlet oxygen and heat.

Tailoring pigment dispersants with polyisobutylene twin-tail structures for electrowetting display application.

We have designed a class of highly hydrophobic dispersants for finely dispersing carbon black and organic pigment nanoparticles in apolar mediums. The synthesis involved the use of polyisobutylene-g-succinic anhydride (PIB-SA) and judiciously selected amines by amidation and imidation. The structures were characterized by infrared spectroscopy for anhydride functionalities in the starting materials and amide/imide linkages in the products. These polymeric forms of dispersants were structurally varied with respects to their PIB molecular weight, twin-tails, and linkages. Their relative performance for dispersing six different pigments in decane was evaluated against solution homogeneity, viscosity, stability, and particle size. The fine dispersion was achieved at particle sizes of ca. 100 nm, with the viscosity as low as 2-3 cP. The measurement of zeta potentials, which varied from -39.8 to -5.1 mV with pigment addition, revealed a strong surface-charge interaction between pigment and PIB dispersant molecules. Examination by TEM (transmission electronic microscope) showed the homogeneous dispersion of the primary structures of pigment particles at ca. 20 nm in diameter. The polymeric dispersants with different PIB tails and imide functionalities could be tailored for pigment stability in the oil phase, which is potentially suitable for the electrowetting devices.