Search results for "Cuspid"
showing 10 items of 157 documents
Oval fiber posts do not improve adaptation to oval-shaped canal walls.
2011
Abstract Introduction Oval fiber posts attempt to provide better adaptation to root canals. The hypothesis of this study was that there are no differences in adaptation of oval and circular fiber posts to canal walls. Methods Posts were inserted in 20 canals; 10 were oval, and 10 were circular. The posts were cemented with composite cement. Coronal, middle, and apical sections were observed through a microscope. The space occupied by the post and the maximum distance between it and the canal wall were calculated. The 2 groups were compared with analysis of variance. In all the analyses the level of significance was set at P Results The proportion of space occupied by the post showed no sign…
Corrigendum to Patterns of ascending aortic dilatation and predictors of surgical replacement of the aorta: A comparison of bicuspid and tricuspid ao…
2020
The authors regret that the author name of Romano and Raffa are incorrect. The corrected author's name are Romano G and Raffa GM. The authors would like to apologise for any inconvenience caused.
Biomechanics and Pathobiology of Aortic Aneurysms
2011
Biomechanical weakening of the aorta leads to aneurysm formation and/or dissection and total biomechanical failure results in rupture, which is often fatal. The most common aneurysm is the abdominal aortic aneurysm (AAA) whereas thoracic aortic aneurysms (TAA) involve the ascending or descending segments of the aorta. Biomechanical strength of the aorta is maintained in part via balance between the integrity of the aortic medial and adventitial extracellular matrix and the health of the mural cells. From a biomechanical perspective, aneurysms rupture or dissect when wall stresses locally exceed the wall strength. Pathobiologic mechanisms, pre-disposing disorders and variability of patient d…
Comparison of hemodynamic and structural indices of ascending thoracic aortic aneurysm as predicted by 2-way FSI, CFD rigid wall simulation and patie…
2018
Patient-specific computational modeling is increasingly being used to predict structural and hemodynamic parameters, especially when current clinical tools are not accessible. Indeed, pathophysiology of ascending thoracic aortic aneurysm (ATAA) has been simulated to quantify the risk of complications by novel prognostic parameters and thus to improve the clinical decision-making process related to the intervention of ATAAs. In this study, the relevance of aneurysmal wall elasticity in determining parameters of clinical importance, such as the wall shear stress (WSS), is discussed together with the significance of applying realistic boundary conditions to consider the aortic stretch and twis…
Heart Valve Abnormalities in Systemic Sclerosis Patients; A Multicenter Cohort Study and Review of the Literature
2020
Background Systemic sclerosis (SSc) is a chronic autoimmune disease that is characterized by vasculopathy and fibrosis of the skin and visceral organs. Heart valve diseases are poorly described and generally not considered typical of SSc. We aimed to describe valvular abnormalities in a multicenter cohort of SSc patients and to investigate their correlation with SSc features. Methods We recruited 118 consecutive SSc patients (male/female, 14/104; mean age, 55.2 ± 12.1 years) in 3 rheumatology centers in Sicily, Italy, from January to October 2019. Results Mitral and tricuspid valve insufficiency was found in 85% and 91% of patients, respectively; regurgitations were generally mild and never…
Biomechanical study on ascending aortic aneurysms associated with quadricuspid aortic valve
2020
The quadricuspid aortic valve (QAV) is a rare anatomical situation and the biomechanical properties are not well known when it is associated with ascending aortic aneurysms (AsAA). The objective is to find out what is the biomechanical properties in such situation and to compare it with the existing data. In a sixty-three-years-old female (BMI 26,4) with hypertension disease, QAV, AsAA of 52 mm, an aortic valve and ascending aorta replacement were performed. The aortic wall sample was collected within 30 mins after replacement, partitioned related to medial, posterior, lateral, and anterior quadrants. The sample was cut in square size (15 mm × 15 mm, n = 13) with marking the circumferential…
In Silico Shear and Intramural Stresses are Linked to Aortic Valve Morphology in Dilated Ascending Aorta
2017
Objective/Background: The development of ascending aortic dilatation in patients with bicuspid aortic valve (BAV) is highly variable, and this makes surgical decision strategies particularly challenging. The purpose of this study was to identify new predictors, other than the well established aortic size, that may help to stratify the risk of aortic dilatation in BAV patients.Methods: Using fluid-structure interaction analysis, both haemodynamic and structural parameters exerted on the ascending aortic wall of patients with either BAV ( n = 21) or tricuspid aortic valve (TAV; n = 13) with comparable age and aortic diameter (42.7 +/- 5.3 mm for BAV and 45.4 +/- 10.0 mm for TAV) were compared…
Focus on the unique mechanisms involved in thoracic aortic aneurysm formation in bicuspid aortic valve versus tricuspid aortic valve patients: clinic…
2013
OBJECTIVES: The involvement of different factors in the onset of thoracic aortic aneurysm (TAA) in patients with a bicuspid aortic valve (BAV) vs those with a tricuspid aortic valve (TAV) is well recognized. However, the molecular, genetic and cellular mechanisms driving TAA remain unclear. The aim of this study was to identify the different mechanisms involved in TAA development in patients with BAV vs TAV. METHODS: Aorta specimens and DNA samples were collected from 24 BAV (18 men and 6 women; mean age: 54.2 ± 14.39 years) and 110 TAV (79 men and 31 women, mean age: 66 ± 9.8 years) patients. A control group of 128 subjects (61 men and 67 woman, mean age: 61.1 ± 5.8 years) was also enrolle…
Outcomes of aortic valve repair according to valve morphology and surgical techniques
2012
OBJECTIVES: The aim of this study was to assess the impact of aortic valve morphology and different surgical aortic valve repair techni- ques on long-term clinical outcomes. METHODS: Between February 2003 and May 2010, 216 patients with aortic insufficiency underwent aortic valve repair in our institu- tion. Ages ranged between 26 and 82 years (mean 53 ± 15 years). Aortic valve dysfunctions, according to functional classification, were: type I in 55 patients (25.5%), type II in 126 (58.3%) and type III in 35 (16.2%). Sixty-six patients (27.7%) had a bicuspid valve. Aortic valve repair techniques included sub-commissural plasty in 138 patients, plication in 84, free-edge reinforcement in 80,…
Difference in hemodynamic and wall stress of ascending thoracic aortic aneurysms with bicuspid and tricuspid aortic valve.
2012
The aortic dissection (AoD) of an ascending thoracic aortic aneurysm (ATAA) initiates when the hemodynamic loads exerted on the aneurysmal wall overcome the adhesive forces holding the elastic layers together. Parallel coupled, two-way fluid–structure interaction (FSI) analyses were performed on patient-specific ATAAs obtained from patients with either bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) to evaluate hemodynamic predictors and wall stresses imparting aneurysm enlargement and AoD. Results showed a left-handed circumferential flow with slower-moving helical pattern in the aneurysm's center for BAV ATAAs whereas a slight deviation of the blood flow toward the anterolater…