Antibacterial performance of a porous Cu-bearing titanium alloy by laser additive manufacturing

Porphyromonas gingivalis (P. gingivalis) is the most common species that causes peri-implantitis. It forms an irreversible dense biofilm and causes inflammation. A novel 3D-printed porous TC4-6Cu alloy was fabricated using selective laser melting (SLM) technology for the dental implant, which is anticipated to inhibit biofilm formation. We attempted to investigate the antibacterial ability and antibacterial mechanism of the 3D-printed porous TC4-6Cu alloy against P. gingivalis. This work used scanning electron microscopy (SEM) and laser confocal microscopy (CLSM) to detect the antimicrobial ability of the alloy against sessile P. gingivalis. The results indicated that the 3D-printed porous TC4-6Cu alloy could cause bacterial fragmentation and deformation. Plate antimicrobial counting experiments showed that the antibacterial rates of the alloy against adherent bacteria and planktonic bacteria after 24 h were 98.05% and 73.92%, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Cu2+ were tested to appraise the antibacterial property of the alloy against planktonic P. gingivalis. The relationship between the antibacterial mechanism of the alloy with oxidative stress was evaluated through ROS fluorescence intensity and protein leakage concentration. The results revealed that the alloy significantly eliminated adherent bacteria and inhibited biofilm formation. Moreover, 3D-printed porous TC4-6Cu alloy demonstrated significant bactericidal ability by inducing the production of reactive oxygen species (ROS), which could result in protein leakage from the bacterial cell membrane. This research may open a new perspective on the development and biomedical applications for dental implantation

Neoadjuvant chemoimmunotherapy cycle number selection for non-small cell lung cancer and clinical outcomes: a real-world analysis

ObjectivesNeoadjuvant chemoimmunotherapy is the optimal choice in the treatment of NSCLC; however, the optimal number of therapeutic cycles remains unclear. The primary aim of this study was to determine the optimal number of neoadjuvant therapeutic cycles in NSCLC.MethodsThis study was a real-world clinical analysis that included patients who received neoadjuvant chemoimmunotherapy followed by surgery from January 2020 to August 2022. Patients were divided into two groups based on the number of therapeutic cycles: 2-cycle group and 3-4-cycles group. The primary endpoint was the major pathological response (MPR) rate.ResultsA total of 251 patients were included: 150 in the 2-cycle group and 101 in the 3-4-cycles group. Baseline characteristics were well-balanced between the groups. The MPR in the 2-cycle group was 57.3% and not significantly different from that of 57.4% in the 3-4-cycles group (p=0.529). Thirty-two patients (31.7%) in the 3-4-cycles group underwent surgery > 42 days after the final cycle of neoadjuvant therapy, significantly more than the 24 patients (16.0%) in the 2-cycle group (p=0.003). The incidence of adverse events related to neoadjuvant therapy was higher in the 3-4-cycles vs 2-cycle groups (72.3% versus 58.0%, respectively; p=0.021), while the 2-cycle group had a higher rate of postoperative morbidities (28.0% versus 12.9%, respectively; p=0.004). Additionally, for patients with ≤ 44.2% regression in diameter on computed tomography after two cycles of treatment, the MPR rate was higher in the 3-4-cycles vs 2-cycle group (47.3% versus 29.9%, respectively; p=0.048). For cases with programmed death-ligand 1 expression, regarding tumor proportion score ≤ 10%, 3-4 cycles of neoadjuvant treatment increased the MPR rate compared with 2 cycles (37.5% versus 9.5%, respectively; p=0.041).ConclusionOur data support the positive role of chemoimmunotherapy in the neoadjuvant treatment of NSCLC. Extending to 3–4 cycles instead of 2 cycles of neoadjuvant chemoimmunotherapy may improve the safety of surgery and result in a lower incidence of postoperative morbidities; however, the MPR rate may not increase significantly. CT re-evaluation during treatment and PD-L1 expression at initial diagnosis are potential indicators to guide the choice of the number of therapeutic cycles

Patients’ expectation and satisfaction with complete denture before and after the therapy

Background/Aim. Difficulties in the acceptance of dentures are multifactorial including psychosocial ones. It is questionable whether the patients’ satisfaction depends only on the complete denture therapy characteristics. The aim of the study was to evaluated patients’ expectation and satisfaction with complete dentures before and after the treatment concerning phonetics, chewing, comfort of use and aesthetics. Methods. Forty complete edentulous patients rated their expectation before and satisfaction after the treatment based on a questionnaire scores. Patient-related variables regarding age, gender and previous experience (whether worn complete denture or not) were also recorded. Results. Patients’ rating for expectations were higher than the satisfaction after treatment regarding phonetics, chewing, comfort of use and aesthetics. A negative significant correlation was shown between the items before and after the treatment rating for phonetics, chewing, comfort of use and aesthetics. No statistical correlation was found between all the evaluated aspects’ (i.e. phonetics, chewing, comfort of use and aesthetics) of expectation and satisfaction, and age, gender, and previous experience except a weak negative correlation noticed between age and comfort of denture use. Conclusion. Patients’ expectations ratings significantly exceeded their satisfactions. Expectations and satisfaction ratings were irrespective of gender and patients previous experience

Evaluation of the Color Stability, Water Sorption, and Solubility of Current Resin Composites

This study aims to assess the color stability, water sorption, and solubility of 11 resin composites as commercially available dental products. Twenty samples (10 mm in diameter and 2 mm in thickness) of each material were fabricated using a customized silicone mold, followed by immersion in each of curry, coffee, wine, and distilled water for 28 days (n = 5). Baseline shade and color changes (ΔE) were measured using a reflection spectrophotometer. The CIE L*, a*, b* system was used to evaluate the color changes. Five samples of each resin composite were applied to test water sorption and solubility according to ISO 4049:2009. As a result, the ∆E values were significantly influenced by each of the three factors (composition of material, solution, time) and the interactions between them (p < 0.001). Highest resistance to discoloration was achieved by Ceram.X One Universal (CXU), followed by Magnafill Putty (MP). Generally, microhybrid composites showed fewer color changes than nanohybrid composites and giomers. DX. Universal and Filtek Z350 XT showed the highest ΔE values in all colorants. All materials tested in this study fulfilled the criteria of ISO 4049:2009; CXU and MP had the lowest water sorption and solubility. The Pearson test showed statistically significant positive correlations between water sorption and ΔE and between solubility and ΔE