30 research outputs found
Biometric Analysis of C-shaped Root Canals in Mandibular Second Molars Using Cone-Beam Computed Tomography
Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed.  Methods and Materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukeyâs test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual wall was thinner in the middle third of the mesial root compared to the distal root (P<0.05). Conclusion: The lingual wall was the thinnest in C-shaped root canals of mandibular second molars of an Iranian population. Type, number and pathway of canals may vary from the orifice to the apex.Keywords: Biometric Identification; C-shape Root Canal; Cone-Beam Computed Tomograph
Antimicrobial efficacy of different concentration of sodium hypochlorite on the biofilm of Enterococcus faecalis at different stages of development
Persistent infection of the root canal due to the presence of resistance bacterial species, such as Enterococcus faecalis, has always been one of the most important reasons for endodontic treatment failure. This study investigated the antimicrobial efficacy of 1%, 2.5 % and 5% sodium hypochlorite in eliminating E. faecalis biofilms at different stages of development.
In this study 4-, 6- and 10-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS) or 1%, 2.5% and 5% NaOCl. Dentin chip suspensions were used for colony forming unit (CFU) counting to estimate remaining E. faecalis counts. Statistical comparison of the means was carried out with Kruskal-Wallis test, and pair-wise comparisons were made by Mann-Whitney U test, at a significance level of P<0.05.
The results showed that 2.5% and 5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 85.73%, 81.88% and 78.62% decreases in bacterial counts in 4-, 6- and 10-week-old biofilms, respectively, which was significantly more than those with PBS (p<0.05).
The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival rate and residual bacteria increased with biofilm aging
Association of Paraoxonase-1 Genotype and Phenotype with Angiogram Positive Coronary Artery Disease
Funding Information: This study was supported by Mashhad and Isfahan University of Medical Sciences. The authors would like to thank technicians of Sina, Sadi, Ghaem catheterization laboratory and technicians of Isfahan Alzahra genetics laboratory.Peer reviewedPublisher PD
A cross-sectional study to test equivalence of low- versus intermediate-flip angle dynamic susceptibility contrast MRI measures of relative cerebral blood volume in patients with high-grade gliomas at 1.5 Tesla field strength
Introduction1.5 Tesla (1.5T) remain a significant field strength for brain imaging worldwide. Recent computer simulations and clinical studies at 3T MRI have suggested that dynamic susceptibility contrast (DSC) MRI using a 30° flip angle (âlow-FAâ) with model-based leakage correction and no gadolinium-based contrast agent (GBCA) preload provides equivalent relative cerebral blood volume (rCBV) measurements to the reference-standard acquisition using a single-dose GBCA preload with a 60° flip angle (âintermediate-FAâ) and model-based leakage correction. However, it remains unclear whether this holds true at 1.5T. The purpose of this study was to test this at 1.5T in human high-grade glioma (HGG) patients.MethodsThis was a single-institution cross-sectional study of patients who had undergone 1.5T MRI for HGG. DSC-MRI consisted of gradient-echo echo-planar imaging (GRE-EPI) with a low-FA without preload (30°/P-); this then subsequently served as a preload for the standard intermediate-FA acquisition (60°/P+). Both normalized (nrCBV) and standardized relative cerebral blood volumes (srCBV) were calculated using model-based leakage correction (C+) with IBNeuroâą software. Whole-enhancing lesion mean and median nrCBV and srCBV from the low- and intermediate-FA methods were compared using the Pearsonâs, Spearmanâs and intraclass correlation coefficients (ICC).ResultsTwenty-three HGG patients composing a total of 31 scans were analyzed. The Pearson and Spearman correlations and ICCs between the 30°/P-/C+ and 60°/P+/C+ acquisitions demonstrated high correlations for both mean and median nrCBV and srCBV.ConclusionOur study provides preliminary evidence that for HGG patients at 1.5T MRI, a low FA, no preload DSC-MRI acquisition can be an appealing alternative to the reference standard higher FA acquisition that utilizes a preload
The Effect of Input-Based and Output-Based Tasks on the Intermediate Iranian EFL Learnersâ Writing Achievement in Terms of Coherent Writing
The present study investigated the effect of form-focused (FoF) tasks on enhancement of Iranian EFL learnersâ coherent writing. In this regard, the researchers compared the effectiveness of dictogloss (DIG) task as an output-based task and consciousness raising (CR) task as an input-based task on teaching writing coherent text. Prior to the experiment, the researchers divided 60 Iranian Intermediate EFL learners based on their scores on the Preliminary English Test (PET) into two groups. Throughout the research a pretest and a posttest which had the same format but different topics were run. The instructional treatment continued for 10 sessions which each session lasted 15 minutes. The required texts which consisted of some cohesive devices were taken from "Elementary Steps to Understanding" book, while the method of teaching, as the name of each group is revealed, was different. After analyzing the gathered data via independent sample t-test, findings revealed that significant, though, the treatment of each group on writing was, there were no significant different between the posttest of these two groups. So there were not any significant difference between the performance of CR group and DIG group on producing cohesive devices in a text
The Effect of Input-Based and Output-Based Tasks on the Intermediate Iranian EFL Learnersâ Writing Achievement in Terms of Coherent Writing
The present study investigated the effect of form-focused (FoF) tasks on enhancement of Iranian EFL learnersâ coherent writing. In this regard, the researchers compared the effectiveness of dictogloss (DIG) task as an output-based task and consciousness raising (CR) task as an input-based task on teaching writing coherent text. Prior to the experiment, the researchers divided 60 Iranian Intermediate EFL learners based on their scores on the Preliminary English Test (PET) into two groups. Throughout the research a pretest and a posttest which had the same format but different topics were run. The instructional treatment continued for 10 sessions which each session lasted 15 minutes. The required texts which consisted of some cohesive devices were taken from "Elementary Steps to Understanding" book, while the method of teaching, as the name of each group is revealed, was different. After analyzing the gathered data via independent sample t-test, findings revealed that significant, though, the treatment of each group on writing was, there were no significant different between the posttest of these two groups. So there were not any significant difference between the performance of CR group and DIG group on producing cohesive devices in a text
A new combination of naringin and trimetazidine protect kidney Mitochondria dysfunction induced by renal Ischemia / Reperfusion injury in rat
Ischemia/reperfusion (IR) injury leads to overproduction of Reactive Oxygen Species (ROS), and disrupts membrane potential that contributes to cell death. The aim of this study was to determine if naringin (NAR), trimetazidine (TMZ) or their combination, protect the kidney mitochondrial from IR injury. Forty rats were randomly allocated into five groups, harboring eight rats each: Sham, IR, NAR (100 mg/kg), TMZ (5 mg/kg) and NAR plus TMZ. Ischemia was induced by obstructing both renal pedicles for 45 min, followed by reperfusion for 4 hours. The mitochondria were isolated to examine the ROS, Malondialdehyde (MDA), Glutathione (GSH), mitochondrial membrane potential (MMP) and mitochondrial viability (MTT). Our findings indicated that IR injury resulted in excessive ROS production, increased MDA levels and decreased GSH, MMP and MMT levels. However, NAR, TMZ or their combination reversed these changes. Interestingly, a higher protection was noted with the combination of both, compared to each drug alone. We speculate that this combination demonstrates a promising process for controlling renal failure, especially with the poor clinical outcome, acquired with NAR alone. This study revealed that pretreatment their combination serves as a promising compound against oxidative stress, leading to suppression of mitochondrial stress pathway and elevation of GSH level
New Insights on Genetic Features of Neu-Laxova Syndrome
ABSTRACTBackground: This study aimed to present a rare case of Neu-Laxova syndrome (NLS) and review the newly revealed genetic features of the disease in hopes to find a way for early interventions.Case report: Female newborn with NLS was born at 30 weeks of gestation to consanguineous parents. The last prenatal ultrasound imaging revealed severe intrauterine growth restriction and microcephaly without polyhydramnios. The newborn had significant dysmorphic features, such as microcephaly, slanted forehead, protruding eye, flattened nose, micrognathia, cleft palate, ichthyosis skin, edematous hands and feet and flexion contractures of the joints. Moreover, she had the usual female karyotype. Results of plain x-ray imaging demonstrated microcephaly, kyphosis, and arthrogryposis.Conclusion: According to the results of this study, NLS is a severe serine deficiency disorder. Given the confirmation of the possibility of diagnosing NLS early in gestation by several studies, it is suggested that early maternal supplementation with serine and glycine be used in families at risk of this disease or those who are diagnosed in early gestation with NLS in order to decrease the severity and fatality of the disease