Search results for "Process"
showing 10 items of 22310 documents
Determination of Bolton tooth-size ratios by digitization, and comparison with the traditional method.
2005
The Bolton Index is one of the most useful calculations for precise orthodontic diagnosis as it shows if there is a correct ratio between dental proportions. However, at times, this calculation is not applied because it is a long and time-consuming procedure compared with digital methods. A new digital method for measuring tooth sizes and for calculating the Anterior (ABI) and the Overall (OBI) Bolton Index was tested on 100 sets of study dental casts of the permanent dentition in a Spanish sample and compared with the traditional method. The reproducibility of this digital method versus the traditional one was analysed to determine intra- and inter-examiner measurement errors by calculatin…
Staging of osteonecrosis of the jaw requires computed tomography for accurate definition of the extent of bony disease
2014
AbstractManagement of osteonecrosis of the jaw associated with antiresorptive agents is challenging, and outcomes are unpredictable. The severity of disease is the main guide to management, and can help to predict prognosis. Most available staging systems for osteonecrosis, including the widely-used American Association of Oral and Maxillofacial Surgeons (AAOMS) system, classify severity on the basis of clinical and radiographic findings. However, clinical inspection and radiography are limited in their ability to identify the extent of necrotic bone disease compared with computed tomography (CT). We have organised a large multicentre retrospective study (known as MISSION) to investigate th…
fMRI-activation patterns in the detection of concealed information rely on memory-related effects
2012
Recent research on potential applications of fMRI in the detection of concealed knowledge primarily ascribed the reported differences in hemodynamic response patterns to deception. This interpretation is challenged by the results of the present study. Participants were required to memorize probe and target items (a banknote and a playing card, each). Subsequently, these items were repeatedly presented along with eight irrelevant items in a modified Guilty Knowledge Test design and participants were instructed to simply acknowledge item presentation by pressing one button after each stimulus. Despite the absence of response monitoring demands and thus overt response conflicts, the experiment…
Covariations among fMRI, skin conductance, and behavioral data during processing of concealed information.
2007
Imaging techniques have been used to elucidate the neural correlates that underlie deception. The scientifically best understood paradigm for the detection of deception, however, the guilty knowledge test (GKT), was rarely used in imaging studies. By transferring a GKT‐paradigm to a functional magnetic resonance imaging (fMRI) study, while additionally quantifying reaction times and skin conductance responses (SCRs), this study aimed at identifying the neural correlates of the behavioral and electrodermal response pattern typically found in GKT examinations. Prior to MR scanning, subjects viewed two specific items (probes) and were instructed to hide their knowledge of these. Two other spec…
Accuracy of check-bite registration and centric condylar position
2002
In a dentate subject a jaw relation can either be determined in maximum intercuspation and is as such given by the occlusal morphology, or the mandibular position can be allocated according to the centric position of the condyles. For comprehensive restorative treatment or analytic measures of the occlusion it is important to record the centric condylar position. Various registration methods have been described in the literature, but there is no consensus on which is the 'best'. The aim of the present study was therefore to assess the accuracy of various registration methods and evaluate a possible influence of the used materials. Four dentists were involved in the clinical part of the stud…
Current state of dental autotransplantation
2010
The aim of this study is to analyse the current situation in dental autotransplantations within the different therapeutic alternatives that the dentist has available to replace a tooth in the dental arcade. For some authors this is an option headed for failure, whereas for others, it is an alternative to keep in mind. In this study we analyse the factors related to the predictability of the technique, based on an analysis of research work published in the scientific literature up to date. We also present two clinical cases performed by our team and their subsequent evaluation. In spite of the satisfactory results seen when reviewing the existing literature, we cannot say that dental autotra…
Altered orientation of spatial attention in depersonalization disorder
2013
Difficulties with concentration are frequent complaints of patients with depersonalization disorder (DPD). Standard neuropsychological tests suggested alterations of the attentional and perceptual systems. To investigate this, the well-validated Spatial Cueing paradigm was used with two different tasks, consisting either in the detection or in the discrimination of visual stimuli. At the start of each trial a cue indicated either the correct (valid) or the incorrect (invalid) position of the upcoming stimulus or was uninformative (neutral). Only under the condition of increased task difficulty (discrimination task) differences between DPD patients and controls were observed. DPD patients sh…
Predicting limiting 'free sugar' consumption using an integrated model of health behavior.
2020
Excess intake of ‘free sugars’ is a key predictor of chronic disease, obesity, and dental ill health. Given the importance of determining modifiable predictors of free sugar-related dietary behaviors, we applied the integrated behavior change model to predict free sugar limiting behaviors. The model includes constructs representing ‘reasoned’ or deliberative processes that lead to action (e.g., social cognition constructs, intentions), and constructs representing ‘non-conscious’ or implicit processes (e.g., implicit attitudes, behavioral automaticity) as predictors of behavior. Undergraduate students (N = 205) completed measures of autonomous and controlled motivation, the theory of planned…
Testing the flexibility of the modified receptive field (MRF) theory: evidence from an unspaced orthography (Thai).
2013
In the current study, we tested the generality of the modified receptive field (MRF) theory (Tydgat & Grainger, 2009) with English native speakers (Experiment 1) and Thai native speakers (Experiment 2). Thai has a distinctive alphabetic orthography with visually complex letters (ฝ ฟ or ผ พ) and nonlinear characteristics and lacks interword spaces. We used a two-alternative forced choice (2AFC) procedure to measure identification accuracy for all positions in a string of five characters, which consisted of Roman script letters, Thai letters, or symbols. For the English speakers, we found a similar pattern of results as in previous studies (i.e., a dissociation between letters and symbols). I…
Chronic alcohol intake abolishes the relationship between dopamine synthesis capacity and learning signals in ventral striatum
2014
Drugs of abuse elicit dopamine release in the ventral striatum, possibly biasing dopamine-driven reinforcement learning towards drug-related reward at the expense of non-drug-related reward. Indeed, in alcohol-dependent patients, reactivity in dopaminergic target areas is shifted from non-drug-related stimuli towards drug-related stimuli. Such 'hijacked' dopamine signals may impair flexible learning from non-drug-related rewards, and thus promote craving for the drug of abuse. Here, we used functional magnetic resonance imaging to measure ventral striatal activation by reward prediction errors (RPEs) during a probabilistic reversal learning task in recently detoxified alcohol-dependent pati…