Shear bond strength of orthodontic brackets to enamel after application of a caries infiltrant

Objective:To examine differences in the shear bond strength of orthodontic brackets on differently mineralized enamel surfaces after applying a caries infiltrant or conventional adhesive.Materials and Methods:A total of 320 bovine incisors were assigned to eight pretreated groups, and the shear force required for debonding was recorded. Residual adhesive was evaluated by light microscopy using the adhesive remnant index. Statistical analysis included Kolmogorov-Smirnov, analysis of variance (ANOVA), and Scheffé tests.Results:The highest bond strength (18.8 ± 4.4 MPa) was obtained after use of the caries infiltrant. More residual adhesive and fewer enamel defects were observed on infiltrated enamel surfaces. Brackets on demineralized enamel produced multiple enamel defects.Conclusions:Acceptable bond strengths were obtained with all material combinations. A caries-infiltrant applied before bracket fixation has a protective effect, especially on demineralized enamel.     

T cell response to the cytomegalovirus major capsid protein (UL86) is dominated by helper cells with a large polyfunctional component and diverse epitope recognition

T cells are crucial in controlling cytomegalovirus (CMV) infection. The CMV major capsid protein (UL86) is frequently recognized by these cells, but the nature of this response has not been explored in detail. In this study, healthy CMV-exposed individuals were examined, and ex vivo peptide stimulation of peripheral blood mononuclear cells and flow-cytometry were used to obtain data, including response prevalence, magnitude, functional profiles, and recognized epitopes. Of 24 subjects, 19 (79%) had a UL86-specific CD4 T cell response rate between 0.03% and 1.4%. This group of individuals exhibited a similar percentage of polyfunctional T cells in their UL86-specific and pp65-specific responses. A total of 8 CD4 T cell epitopes were identified. In contrast, CD8 T cell responses to UL86 were rare and small. UL86 is of interest for monitoring the response to CMV.     

Hemodynamics of constrictive pericarditis and restrictive cardiomyopathy

Constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM) are indolent disabling diseases of diastolic function. The two conditions share common pathophysiologic features, resulting in similar and overlapping clinical presentations, echocardiographic findings, and hemodynamic characteristics. However, their clinical course differs, as CP is surgically curable whereas RCM is a chronic condition managed medically. Separating these two entities is based on delineation of anatomic and physiologic derangements employing multimodality hemodynamic interrogation by advanced imaging techniques (Echo–Doppler, CT, and especially MRI) combined with sophisticated invasive hemodynamics.     

Maximum forces applied to the orbital floor after fractures

ABSTRACT: The objective of this study was to measure the force on and displacement of completely detached intraorbital tissue from thebony orbit, as a worst-case scenario after orbital trauma, to preserve the maximum load and predict the necessary strength of reconstruction materials. Six fresh-frozen human heads were used, and orbital floor defects in the right and left orbits were created by the direct impact of 3.0 J onto the globe and infraorbital rim. The orbital floor defect sizes and displacements were evaluated after performing a Le Fort I osteotomy. In addition, after the repositioning of the completely detached intraorbital tissue, the forces and displacements were measured. The mean orbital floor defect sizes were 208.3 (SD, 33.4) mm for globe impacts and 221.8 (SD, 53.1) mm for infraorbital impacts. The mean intraorbital tissue displacement after the impact and before repositioning was 5.6 (SD, 1.0) mm for globe impacts and 2.8 (SD, 0.7) mm for infraorbital impacts. After repositioning, the displacements were 0.8 (SD, 0.5) mm and 1.1 (SD, 0.7) mm, respectively. The measured forces were 0.10519 (SD, 0.00958) N without the incorporation and approximately 0.11128 (SD, 0.003599) N with the incorporation of reconstruction materials. The maximum forces on the completely detached orbital tissue were minimal (～0.11 N) and suggest the use of collagen membranes as reconstruction materials for orbital floor defects, at least in medium-sized fractures.     

Percutaneous mechanical support for the failing right heart

Right ventricular (RV) failure is an increasingly common clinical problem that may require mechanical support. In contrast to severe left ventricular failure, RV failure is typically more reversible. Therefore, application of shorter-term percutaneous support devices is potentially attractive. Current innovations promise greater availability of such percutaneous RV support devices. This article considers the available mechanical approaches to provide hemodynamic support to treat profound RV failure in the common clinical scenarios in which percutaneous mechanical RV support may be most beneficial.     

Zur Ätiologie der Sucht

A psychodramatic explanatory model regarding the origin and upkeep of addiction is prepared in this article, which also includes substance-related addictions and behavioural dependencies. Negative spirals, resulting in the development and manifestation of abusive and addictive behaviour are described with the aid of psychodramatic role-theory and the two forces of the spontaneity-creativity circle (motivational dynamics and self-enhancing feedback).