Search

Background: Many practitioners have questioned whether the construction method of pediatric zirconia crowns impacts the periodontal health and clinical performance of severely decayed primary molars. The objective of this study was to compare the periodontal health and clinical performance of primary molars restored with custom-made zirconia crowns (CZCs) and prefabricated zirconia crowns. Methods: Twenty primary molars indicated for crown restorations were selected from ten patients (5–9 years old) randomly. Each patient received two pediatric zirconia crowns constructed by two different methods: one custom-made and one prefabricated. The primary molars were divided into two groups: Group 1: primary molars received CZCs and Group 2: primary molars received prefabricated zirconia crowns (PZCs). Results: After a 12-month follow-up, there was no statistically significant difference between the periodontal health of primary molars restored with custom-made and prefabricated zirconia crowns. The clinical performance of primary molars restored with CZCs was statistically significantly higher than those restored with PZCs in terms of retention and fracture resistance (P ≤ 0.05). Conclusions: The construction method of pediatric zirconia crowns does not significantly affect the periodontal health of primary molars; however, clinical performance is significantly affected in terms of retention and fracture resistance. Clinical Significance: A CZC is an excellent alternative option, especially for primary molars whose permanent successors still have a long time to erupt. The PZC is a quick and easy restoration, but the technique is sensitive.

ObjectivesPatients with atrial fibrillation (AF) have lower left atrial (LA) strain, which is a predictor for LA function. Here, we evaluated the prognostic value of LA strain to predict the rhythm outcome in patients with persistent AF undergoing LA cryoablation concomitant to minimally invasive mitral valve repair.MethodsBetween 01/2016 and 12/2020, 72 patients with persistent AF underwent LA cryoablation during minimally invasive mitral valve surgery. All patients received a complete LA lesion set and left atrial appendage (LAA) closure with a clip. All patients received preoperative transthoracic echocardiography (TTE) with LA and left ventricular strain measurements. Preoperative LA and LV strain analysis was correlated with postoperative rhythm outcome.ResultsThe mean age of the patients was 66.9 ± 7.2 years, of whom 42 (58%) were male patients. No major ablation-related complications occurred in any of the patients. Successful LAA closure was confirmed by intraoperative echocardiography in all patients. The 1-year survival rate was 97%. Freedom from AF at 12 months was 72% and 68% off antiarrhythmic drugs. Preoperative LA strain values were statistically significantly higher in patients with freedom from AF at 12 months of follow-up (12.7% ± 6.9% vs. 4.9% ± 4.1%, p = 0.006). Preoperative LV strain value was not associated with postoperative rhythm outcome. In multivariate logistic regression analysis, LA strain (p

The velocity distribution of flow in an eccentric cylindrical annulus is determined in an attempt to investigate the vertical capillary rise in the channel. The critical values of the radii ratio and the eccentricity at which the capillary rise changes from oscillatory to monotone or vice versa are determined. For a particular aspect ratio, the rise becomes monotonic as the eccentricity increases. The oscillations are also dampened as the annulus becomes thinner. These critical values depend on Galileo and Bond numbers as well as the contact angle. The results reduce to the limiting cases of concentric and fully eccentric annuli. The critical values are also calculated for the special arrangements when the radii ratios are 1 and 0. The latter limit is in perfect agreement with the conditions found in the literature for the classical circular channel.

BackgroundAtrial fibrillation (AF) is common in patients with heart failure resulting in a high prevalence of AF in patients receiving Cardiac Resynchronization Therapy (CRT) implantation. In patients, unsuitable for transvenous left ventricular (LV)-lead implantation, epicardial LV-lead implantation represents a valuable alternative. Epicardial LV-lead placement can be achieved totally thoracoscopical or via minimally invasive left lateral thoracotomy. In patients with atrial fibrillation, concomitant left atrial appendage (LAA) clipping is feasible via the same access. Therefore, the aim of our study was the analysis of safety and efficacy of epicardial LV lead implantation and concomitant LAA clipping via minimally invasive left-lateral thoracotomy.MethodsBetween December 2019 and March 2022, 8 patients received minimally invasive left atrial LV-lead implantation with concomitant LAA closure using the AtriClip. Transesophageal echocardiography (TEE) was performed to intraoperatively guide and control LAA closure.ResultsMean patients age was 64 ± 11.2 years, 67% were male patients. Minimally invasive left-lateral thoracotomy was used in 6 patients while a totally thoracoscopic approach was performed in 2 cases. Epicardial lead implantation was successfully performed in all patients with good pacing threshold (mean 0.8 ± 0.2 V) and sensing values (10.1 ± 2.3 mV). Posterolateral position of the LV lead was achieved in all patients. Furthermore, successful LAA closure was confirmed during TEE in all patients. No procedure-related complications occurred in any of the patients. Two patients additionally received simultaneous laser lead extraction during the same procedure. Complete lead extraction was achieved in both patients. All patients were extubated in the OR and had an uneventful postoperative course.ConclusionOur study highlights a novel treatment approach for patients with atrial fibrillation and the necessity of epicardial LV leads. Placement of a posterolateral LV lead position with concomitant occlusion of the left atrial appendage via a minimally-invasive left-lateral thoracotomy or even a totally thoracoscopic approach is safe and feasible with superior cosmetic result and complete occlusion of the left atrial appendage.

We present a rare exact solution of the Navier–Stokes equations for the Hagen–Poiseuille flow through a quarter-elliptic tube. Utilizing the separation of variables method, we derive the solution and report expressions for both the volumetric flow rate and the friction factor–Reynolds number product.

BackgroundMinimally-invasive (MIS) mitral valve (MV) surgery has become standard therapy in many cardiac surgery centers. While femoral arterial perfusion is the preferred cannulation strategy in MIS mitral valve surgery, retrograde arterial perfusion is known to be associated with an increased risk for cerebral atheroembolism, particularly in atherosclerosis patients. Therefore, antegrade perfusion may be beneficial in such cases. This analysis aimed to compare outcomes of antegrade axillary vs. retrograde femoral perfusion in the MIS mitral valve surgery.MethodsThis analysis includes 50 consecutive patients who underwent MIS between 2016 and 2020 using arterial cannulation of right axillary artery (Group A) due to severe aortic arteriosclerosis. Perioperative outcomes of the study group were compared with a historical control group of retrograde femoral perfusion (Group F) which was adjusted for age and gender (n = 50). Primary endpoint of the study was in-hospital mortality and perioperative cerebrovascular events.ResultsPatients in group A had a significantly higher perioperative risk as compared to Group F (EuroSCORE II: 3.9 ± 2.5 vs. 1.6 ± 1.5; p = 0.001; STS-Score: 2.1 ± 1.4 vs. 1.3 ± 0.6; p = 0.023). Cardiopulmonary bypass time (group A: 172 ± 46; group F: 178 ± 51 min; p = 0.627) and duration of surgery (group A: 260 ± 65; group F: 257 ± 69 min; p = 0.870) were similar. However, aortic cross clamp time was significantly shorter in group A as compared to group F (86 ± 20 vs. 111 ± 29 min, p < 0.001). There was no perioperative stroke in either groups. In-hospital mortality was similar in both groups (group A: 1 patient; group F: 0 patients; p = 0.289). In group A, one patient required central aortic repair due to intraoperative aortic dissection. No further cardiovascular events occurred in Group A patients.ConclusionSelective use of antegrade axillary artery perfusion in patients with systemic atherosclerosis shows similar in-hospital outcomes as compared to lower risk patients undergoing retrograde femoral perfusion. Patients with higher perioperative risk and severe atherosclerosis can be safely treated via the minimally invasive approach with antegrade axillary perfusion.

Abstract Objective: Left ventricular assist device (LVAD) implantation with concomitant Dor plasty is only reported anecdotally. We herein aimed to describe our experience with LVAD and concomitant Dor procedures and describe long-term outcomes of this special subset of heart failure patients. Methods: Between January/2010 and December/2018, 144 patients received LVAD therapy at our institution. Of those, five patients (80% male, 60.4±7.2 years) presented with an apical aneurysm and received concomitant Dor plasty. Apical aneurysms presented diameter between 75 and 98 mm, with one impending rupture. Results: Procedural success was achieved in all patients. No unplanned right ventricular assist device implantation occurred. Furthermore, no acute 30-day mortality was seen. In follow-up, one patient was lost due to intentional disconnection of the driveline. One patient underwent heart transplantation on postoperative day 630. The remaining three patients are still on device with sufficient flow; pump thromboses were successfully managed by lysis therapy in one patient. Conclusion: LVAD implantation with concomitant Dor procedure is feasible, safe, and occasionally performed in patients with ischemic cardiomyopathy. Major advantages are prevention of thromboembolism and facilitation of LVAD placement by improving pump stability and warranting midventricular, coaxial alignment of the inflow cannula. In long-term follow-up, no adverse event associated with Dor plasty was observed.

In this note, the dimensions of elliptic and semielliptic tubes in which the capillary rise starts oscillating about its Jurin’s height are determined. Comparisons with the capillary rise in the classical circular and in semicircular tubes are made.

Background and Objectives: In patients with paroxysmal atrial fibrillation (AF) undergoing CABG or aortic valve surgery, many surgeons are not willing to open the left atrium to perform a complete left-sided Cox-Maze lesion set. Pulmonary vein isolation (PVI) is often favored in those patients. We investigated the outcome of patients with isolated pulmonary vein isolation compared to those receiving an extended left atrial (LA) lesion set. Materials and Methods: Between 2003 and 2016, 817 patients received concomitant surgical AF ablation in our institution. A total of 268 patients with paroxysmal AF were treated by surgical ablation concomitant to AVR or CABG. Of those, 86 patients underwent a complete left-sided lesion set, while 182 patients were treated with an isolated pulmonary vein isolation. The primary endpoint was freedom from atrial fibrillation at 12 months’ follow-up. Results: There were no statistically significant differences regarding baseline characteristics. No major ablation-related complications were observed in any of the groups. In the PVI group, three patients (1.6%) had an intraoperative stroke, while two (2.3%) patients experienced a stroke in the LA ablation group (p = 0.98). In-hospital mortality was 3.4% in the PVI group, and 2.8% in the extended LA group (p = 0.33). Freedom from AF at 12 months’ follow-up was 76% in the extended LA ablation group and 70% in the PVI group, showing no statistically significant difference (p = 0.32). Conclusion: Surgical AF ablation concomitant to CABG or AVR in patients with paroxysmal AF is safe and effective. There was no statistically significant difference between the compared lesion sets in terms of freedom from AF, survival or stroke rate after 12 months.

The printing industry has become more development than before, as well as the challenges that related to quality and consistency of colors results, especially with the repetition of printing operations in the packaging field. The using of measurement devices is very important due to the many changes that occur on printing materials in general and on paper and inks in particular. And their were many sources of cellulose plants and other sources of paper manufacturing, as well as the entry of recycling operations in this industry , and also many producing companies are manufacturing paper with different technology in the world.Also there are a several companies producing inks and the development of the manufacture of chemical›s Pigment compounds and sources of oils, resins and other additives.All of that factors made it necessary and to use measurement devices, especially in the production of repeated printing to ensure the stability of results and quality control in each process.In this research we will highlight on the most important types of paper in general and especially the paper that used in this research .And we will print models of the fourteen basic colors of the Pan tone and will make measurements using the spectrophotometer to register and monitor the differences resulting from the different surface finishing of the paper coated - glossy/matt and uncoated.As well as registered the results and values of the difference between the print samples and Pantone.In this research, we will highlight on the colors deviations with the different surface finishing of the paper and fixed the other factors to identify the reasons that lead to the deviation of the results with the use of the same materials and equipment and using of different types of finishing surface of paper.

Background: The maximum conservation of tooth structure and the use of restorative materials with elastic modulus close to the dental structure may promote greater longevity of the tooth/restoration complex. This study was conducted to evaluate the effect of cavity design and material type on fracture resistance and failure pattern of molars restored by computer-aided design/computer-aided manufacturing (CAD/CAM) inlays/onlays. Materials and Methods: In this in vitro study, 55 human maxillary molars were embedded in resin blocks and divided into control group (CG) and five main groups: Group 1: Inlay, Group 2: Conventional onlay/mesiobuccal (MB), Group 3: Conservative onlay/MB, Group 4: Conventional onlay/MB and distobuccal (DB), and Group 5: Conservative onlay/MB and DB. Then, each group was divided into two subgroups: (A) CeraSmart (CS) and (B) Katana Zirconia (KZ). Restorations were cemented by RelyX Ultimate and then thermocycled. The universal testing machine was used to measure fracture loads. Failure was determined using a magnifying lens. Data were statistically analyzed using ANOVA followed by Tukey's post hoc test (P < 0.05). Results: Group 5 showed the highest significant fracture load, whereas the least significant value was recorded in Group 2. KZ recorded higher significant fracture loads than CS in all tested groups. Groups 1, 2, and 3 restored by CS showed lower fracture load than CG, but the difference was insignificant with Group 1. CS restorations showed restorable failure, while unrestorable pattern was predominant in KZ restorations (P < 0.05). Conclusion: KZ inlays and onlays can be used safely in terms of fracture resistance as both have values exceed the physiologic requirements. CS inlays and onlays/MB and DB are of fracture resistance comparable to intact teeth. The use of conservative onlay design with more cusp coverage guarantees better resistance of CS restorations. Being force absorbing material, the predominant failure of teeth restored by CS was restorable.