Effect of tooth color on the accuracy of intraoral complete arch scanning under different light conditions using a zirconia restoration model.

STATEMENT OF PROBLEM: Information regarding the effect of tooth color under different light conditions on the accuracy of intraoral complete arch scanning is limited. PURPOSE: The purpose of this in vitro study was to evaluate the effect of color and ambient light conditions on the accuracy of mandibular complete arch scanning with an intraoral scanner (IOS) using a zirconia restoration model with different shades. MATERIAL AND METHODS: Five mandible dentition models with zirconia restorations of different shades were fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM). The spectral reflectance and transmittance curves were collected with a spectrophotometer to determine color parameters (Rb, T, S+A, L*, a*, b*, C*, and h). Under 4 different lighting conditions: no light (ZL), natural light (NL), room light (RL), and chair light (CL), each model was scanned 10 times by using an IOS (TRIOS 3). Three-dimensional (3D) deviation analysis and a linear deviation analysis were performed for an accurate quantitative measurement of intraoral scanning. The multivariate test was used to determine significant differences in 3D deviation and linear deviation among groups. The multiple linear regression test was conducted to investigate the relevant independent factors of mean absolute 3D deviation. RESULTS: The 3D deviation analysis showed that the mean absolute 3D deviation of 3M2 model scanning was the lowest (P<.001). Moreover, under CL and RL, the accuracy results from the 3M2 model scan were demonstrated as significantly better than the tested scans under other light conditions (P=.021). The result of the linear deviation analysis indicated that the variation in distance was only significant between the bilateral canines (P=.032). Ambient light conditions, C*, and h were factors influencing mean absolute 3D deviation (R2=0.593, P<.001). CONCLUSIONS: Color change influenced the accuracy of intraoral mandibular complete arch scanning under different light conditions. This effect may be attributable to the interaction between the ambient light condition and color parameters such as C* and h.

The effectiveness of different concentrations of chlorhexidine for prevention of ventilator-associated pneumonia: a meta-analysis.

AIMS AND OBJECTIVES: To evaluate the effectiveness of chlorhexidine for the prevention of ventilator-associated pneumonia and explore the preferred concentration of chlorhexidine. BACKGROUND: The implementation of effective oral care measures could reduce the incidence of ventilator-associated pneumonia, but among several randomised controlled trials, whether using chlorhexidine is effective and which concentration is more appropriate remain controversial. DESIGN: A meta-analysis was conducted. METHODS: We searched the Cochrane Library, PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature, China Biology Medicine disc and Chinese National Knowledge Infrastructure to collect randomised controlled trials of mechanically ventilated adult patients receiving oral care with chlorhexidine to prevent ventilator-associated pneumonia. The quality of randomised controlled trials was critically appraised, data were extracted by two reviewers independently, and disagreement was resolved by consensus. Meta-analyses were conducted for the eligible randomised controlled trials by revman 5.1. Relative risks and 95% CIs were calculated with the Mantel-Haenszel model, and heterogeneity was assessed with the I(2) test. RESULTS: Eighteen randomised controlled trials were included and a meta-analysis was used. All studies indicated chlorhexidine could significantly prevent and reduce the incidence of ventilator-associated pneumonia [RR = 0·59, 95% CI (0·50-0·69), p < 0·00001]. Nine studies showed 0·12% chlorhexidine had a significant effect [RR = 0·53, 95% CI (0·43-0·67), p < 0·00001]. Three studies proved the effect of the 2% chlorhexidine on the prevention of ventilator-associated pneumonia [RR = 0·55, 95% CI (0·37-0·81), p = 0·002]. CONCLUSION: Chlorhexidine can prevent and reduce the incidence of ventilator-associated pneumonia. Chlorhexidine of 0·12% has the best effect on the prevention of ventilator-associated pneumonia according to the meta-analysis, cost analysis, adverse reactions and drug resistance analysis. RELEVANCE TO CLINICAL PRACTICE: Ventilator-associated pneumonia remains a leading cause of morbidity and mortality in intensive care unit, and implementing effective oral care can reduce the incidence of ventilator-associated pneumonia. Chlorhexidine of 0·12% is recommended in our study.

Transdermal delivery of brucine-encapsulated liposomes significantly enhances anti-tumor outcomes in treating triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is always the most challenging breast cancer subtype. Herein, brucine, encapsulated in peptide-modified liposomes, was proposed for treating TNBC by transdermal delivery. For the TD peptide-modified brucine-loaded liposome (Bru-TD-Lip) we developed, it presents high encapsulation efficiency of brucine and stability. In vitro, Bru-TD-Lip shows the enhanced percutaneous permeability of brucine, is able to readily enter TNBC cells, and significantly inhibits the proliferation, migration, and invasion of these cells. In vivo, through transdermal delivery, Bru-TD-Lip presents good biosafety and anti-tumor efficacy. The transdermal delivery of Bru-TD-Lip effectively targets and inhibits subcutaneous mammary carcinogenesis in female nude mice. Compared with oral administration, the transdermal delivery significantly reduces the damage of brucine to major organs and enhances the antitumor outcomes of brucine in treating TNBC. This study provides a new therapeutic strategy for treating triple-negative breast cancer by brucine.

Efficacy of intramyocardial injection of Algisyl-LVR for the treatment of ischemic heart failure in swine.

BACKGROUND: Progressive thinning and dilation of the LV due to ischemic heart failure (IHF) increases wall stress and myocardial oxygen consumption. Injectable biopolymers implanted in the myocardial wall have been used to increase wall thickness to reduce chamber volume, decrease wall stress, and improve cardiac function. We sought to evaluate the efficacy of a biopolymer (Algisyl-LVR) to prevent left ventricular (LV) remodeling in a swine model of IHF. METHODS: IHF was induced in 11 swine by occluding the marginal obtuse branches of the left circumflex artery. Eight weeks later, Algisyl-LVR was injected into the LV myocardial free wall in five of the 11 animals. Echocardiographic examinations were done every 2weeks for 16weeks. RESULTS: Within eight weeks of treatment, the ejection fraction increased from 30.5%±7.7% to 42.4%±3.5% (treated group) vs. 37.3%±3.8% to 34.3%±2.9% (control), p<0.01. Stroke volume increased from 18.5±9.3mL to 41.3±13.3mL (treated group) vs. 25.4±2.3mL to 31.4±5.3mL (control), p<0.05. Wall thickness in end-diastole of the infarcted region changed from 0.69±0.06cm to 0.81±0.13cm (treated group) vs. 0.73±0.09cm to 0.68±0.11cm (control), p<0.05. Sphericity index remained almost unchanged after treatment, although differences were found at the end of the study between both groups (p<0.001). Average myofiber stress changed from 16.3±5.8kPa to 10.2±4.0kPa (treated group) vs. 15.2±4.8kPa to 17.9±5.6kPa (control), p<0.05. CONCLUSIONS: Algisyl-LVR is an effective strategy that serves as a micro-LV assist device to reduce stress and hence prevent or reverse maladaptive cardiac remodeling caused by IHF in swine.