Handedness of orthodontists and its impact on practice

Objective: To assess the handedness prevelance of orthodontists and analyse the discomfort of left-handed orthodontists on practice.Materials and Methods: A questionnaire about the laterality of orthodontists and their discomfort was prepared and distributed to our orthodontic society members. 173 questionnaires were investigated.Results: Fifteen of the participants were left-handed individuals. Of all the 15 samples, only 1 practitioner had been educated with left hand manipulation while studying dentistry. One of the 7 private practioners preferred left-handed chair for his clinic. Regarding left-handed participants working with right-sided chair, 4 of them thought this situation depresses their treatment quality and 9 of them refused. Most of the left-handed participants complaint about the university education.Conclusion: Left-handed orthodontists afford to adapt themselves to a right-handed world. They could to be educated on left-handed dental chairs to display  a more skillful clinical performance

Analysis of the common genetic component of large-vessel vasculitides through a meta- Immunochip strategy

Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are major forms of large-vessel vasculitis (LVV) that share clinical features. To evaluate their genetic similarities, we analysed Immunochip genotyping data from 1,434 LVV patients and 3,814 unaffected controls. Genetic pleiotropy was also estimated. The HLA region harboured the main disease-specific associations. GCA was mostly associated with class II genes (HLA-DRB1/HLA-DQA1) whereas TAK was mostly associated with class I genes (HLA-B/MICA). Both the statistical significance and effect size of the HLA signals were considerably reduced in the cross-disease meta-analysis in comparison with the analysis of GCA and TAK separately. Consequently, no significant genetic correlation between these two diseases was observed when HLA variants were tested. Outside the HLA region, only one polymorphism located nearby the IL12B gene surpassed the study-wide significance threshold in the meta-analysis of the discovery datasets (rs755374, P?=?7.54E-07; ORGCA?=?1.19, ORTAK?=?1.50). This marker was confirmed as novel GCA risk factor using four additional cohorts (PGCA?=?5.52E-04, ORGCA?=?1.16). Taken together, our results provide evidence of strong genetic differences between GCA and TAK in the HLA. Outside this region, common susceptibility factors were suggested, especially within the IL12B locus

Autapse-induced multiple coherence resonance in single neurons and neuronal networks

We study the effects of electrical and chemical autapse on the temporal coherence or firing regularity of single stochastic Hodgkin-Huxley neurons and scale-free neuronal networks. Also, we study the effects of chemical autapse on the occurrence of spatial synchronization in scale-free neuronal networks. Irrespective of the type of autapse, we observe autaptic time delay induced multiple coherence resonance for appropriately tuned autaptic conductance levels in single neurons. More precisely, we show that in the presence of an electrical autapse, there is an optimal intensity of channel noise inducing the multiple coherence resonance, whereas in the presence of chemical autapse the occurrence of multiple coherence resonance is less sensitive to the channel noise intensity. At the network level, we find autaptic time delay induced multiple coherence resonance and synchronization transitions, occurring at approximately the same delay lengths. We show that these two phenomena can arise only at a specific range of the coupling strength, and that they can be observed independently of the average degree of the network

An Atypical Giant Right Atrial Myxoma Presented with Minimal Symptoms

IntroductionPrimary tumours of the heart are not common and the prevalence of cardiac tumors ranges from 0,001% to 0,3% at autopsy [1]. Over 70% of primary cardiac tumors are benign and the most common form of these primary tumours are myxomas. Most of the myxomas are located in the left atrium (%75–80), arising from the interatrial septum at the border of the fossa ovalis [2]. Larger tumors are more likely to be associated with cardiovascular symptoms [3]. Commonly observed symptoms and signs are dyspnea, pulmonary edema, cough, peripheral edema and fatigue. Constitutional symptoms (fever, weight loss) are seen in around 30% of patients. Laboratory abnormalities (anemia and elevations in the erythrocyte sedimentation rate, C-reactive protein) are present in 35 % of patients [4].This case report show us discrepancy between giant right atrial myxoma and atypical symptom of patient. Once a cardiac myxoma is diagnosed, surgical excision should be performed without delays because of the risk of thromboembolic events [5-7], syncope and sudden cardiac death. Generally, surgical treatment is definitive and recurrence is uncommon.</p

Mandibular anterior bony support and incisor crowding: Is there a relationship?

Introduction: The aim of this study was to test the null hypothesis that increased irregularity of the mandibular incisors is associated with a reduction in the alveolar support on cone-beam computed tomographic sections. Methods: From a sample of 1100 digital volumetric tomographs, 125 tomographs of subjects with Class I malocclusion (mean age, 21.6 +/- 4.8 years) were selected for this study. An irregularity index was used to categorize these tomographs as having mild, moderate, or severe crowding. All tomographs were taken by using an iCAT (Imaging Sciences International, Hatfield, Pa) imaging device. The following parameters were measured on the sections corresponding to the 4 mandibular incisors with the iCAT software: height, thickness, and area of the entire symphysis; height, thickness, and area of the cancellous bone of the symphysis; and distance between the vestibular and lingual cortices. For the statistical evaluation, independent samples t test, analysis of variance, and the Tukey HSD test were used at an alpha level 0.05. The Pearson correlation coefficient and a simple linear regression were calculated to determine the relationship between mandibular anterior bony support and incisor crowding. Results: Almost all mandibular anterior bone measurements were greater in the male subjects than in the female subjects (height of the mandibular symphysis, P<0.001; cancellous bone height, P<0.001). Female subjects with mild crowding had higher values for cancellous bone height (P=0.025) and vestibular cancellous bone thickness (P=0.004) than did those with severe crowding. However, no differences were detected in the male subjects. Additionally, significant correlations were determined between incisor crowding and thickness of the mandibular symphysis, cancellous bone thickness, and the vestibular part of cancellous bone thickness in female subjects. Conclusions: Significant relationships were found between the measures of mandibular incisor crowding and basal bone dimensions in female subjects. Except for the vestibular part of cancellous bone thickness, all mandibular incisor bone measurements were greater in the male subjects than in the female subjects. (Am J Orthod Dentofacial Orthop 2012; 142: 645-53

Cone-beam computed tomography evaluation of relationship between tongue volume and lower incisor irregularity

The aim of this study was to evaluate the relationship between the tongue volume and lower incisor irregularity, using cone-beam computed tomography (CBCT), and to identify the possible gender differences. CBCT images of 60 patients between 16 and 36 years of age were selected from 1400 sets of images in the database. Tomography was carried out using iCAT (R) (Imaging Sciences International, Hatfield, Pennsylvania, USA) and segmentation was carried out by using Mimics 10.1 software (Materialise NV, Leuven, Belgium). The tongue volume was calculated by using the volume of the voxels from the scan and the number of voxels selected for a given mask. Lower incisor crowding was measured with the Little's irregularity index and divided into three groups: mild, moderate, and severe. Independent samples t-test, analysis of variance (ANOVA), and Tukey test were used at P < 0.05 level. Pearson correlation coefficients and linear regression model were calculated to determine the correlation between tongue volume and incisor irregularity. No significant gender dimorphism was found for the tongue volume (females: 28.13 +/- 8.54 cm(3) and males: 31.02 +/- 9.75 cm(3)). According to ANOVA, there was statistically significant difference in the tongue volume measurements among subjects with different levels of irregularity. Tukey analysis indicated that mild irregularity group (33.97 cm(3)) showed higher values for tongue volume than severe irregularity group (26.60 cm(3); P = 0.025). The relationship between incisor irregularity and tongue volume was evaluated for both genders and significant inverse correlation (r = -0.429; P = 0.029) was determined between lower incisor irregularity and tongue volume in males. In female group, no signifi cant correlation was determined between tongue volume and incisor irregularity

Brown tumor of the maxilla associated with primary hyperparathyroidism

Brown tumors represent the terminal stage of the remodeling processes during primary or secondary hyperparathyroidism. During the last three decades primary hyperparathyroidism has been recognized much more commonly and the increase has generally been attributed to the routine determination of calcium by new automated methods and the advent of new and more objective parathyroid hormone radioimmunoassay techniques. Early diagnosis and successful treatment of the disease have made clinical evidence of bone disease uncommon. While, the mandible is the most frequently involved bone in the head and neck region, maxillary involvement is extremely rare. A case of brown tumor on the maxilla associated with primary hyperparathyroidism is reported. This patient presented multiple skeletal lesions, which are uncommonly seen nowadays. The diagnosis was suggested by the clinical history and confirmed by biochemical, radiological and histopathological determinations. Excision of a parathyroid adenoma normalized the metabolic status. Excision of the maxillary mass led both histo pathological confirmation of the disease and early masticator rehabilitation. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved

Cone-beam computed tomography assessment of mandibular asymmetry in unilateral cleft lip and palate patients

Objective: To determine whether there is any difference between the cleft and non-cleft sides of the mandible in unilateral cleft lip and palate (UCLP) patients, or the right and left sides in control patients; and to determine if there is any difference between the mandibular asymmetry of UCLP patients and that of control patients. Methods: We examined cone-beam computed tomography (CBCT) scans of 15 patients with UCLP and 15 age- and gender-matched control patients. We evaluated 8 linear, 3 surface, and 3 volumetric measurements and compared the cleft/non-cleft sides of UCLP patients and the right/left sides of controls. Results: There were no statistically significant gender differences in any linear, surface, or volumetric measurement. The single significant side-to-side difference in UCLP patients was a longer coronoid unit on the cleft side than on the non-cleft side (p = 0.046). Body volume was significantly lower in the UCLP group than in the control group (p = 0.008). Conclusions: In general, UCLP patients have symmetrical mandibles, although the coronoid unit length is significantly longer on the cleft side than on the non-cleft side. UCLP patients and controls differed only in body volume. (Korean J Orthod 2011;41(6): 431-439

Mandibular asymmetry in unilateral and bilateral posterior crossbite patients using cone-beam computed tomography

Objective: To test the hypotheses that (1) there is no difference in mandibular asymmetry between the crossbite and normal side in a unilateral crossbite group (UCG) and between the right and left sides in a bilateral crossbite group (BCG) and a control group (CG); and (2) there is no significant difference in mandibular asymmetry among crossbite groups and control group