Effects of Ultrasonic Scaling and Hand-Activated Scaling on Tactile Sensitivity in Dental Hygiene Students

This study was conducted in order to determine if tactile sensitivity varies in dental hygiene students who use the ultrasonic scaler as compared to those who scale with handactivated instruments. A convenience sample of 40 consenting, first year dental hygiene students were randomly assigned to one of two groups. The 40 students had not yet used the ultrasonic scaler nor had any history of injuries or disabilities to the dominant arm, wrist or hand. After establishing a baseline tactile sensitivity score with the Vibratory Sensory Analyzer (VSA), experimental group subjects used the ultrasonic scaler to remove 4cc\u27s of artificial calculus from a typodont in a controlled, simulated clinical setting for 45-minutes while each control subject manually scaled 4cc\u27s of artificial calculus on a typodont in a controlled, simulated situation for 45-minutes. Tactile sensitivity scores were obtained using the VSA immediately following exposure to either the ultrasonic scaler or hand-activated scaling instruments. Analysis of variance with one repeated measures factor was used to determine between group and within group differences on the pretest and post-test tactile sensitivity scores. Results revealed that following a 45- minute scaling session with the ultrasonic scaler, tactile sensitivity increased. Pre to posttest changes in tactile sensitivity for the ultrasonic scaling group exhibited a much larger threshold as compared to those in the hand-activated scaling group, supporting a gain in students\u27 level of sensitivity with stimulus (vibration). Tactile sensitivity decreased in those who used hand-activated scaling instruments. The thumb, index and middle fingers of students in both groups showed similarities in tactile sensitivity, with the index finger being the most sensitive. Ultrasonic scalers allow the hygienist to exert less pressure and decrease pinching and gripping forces, therefore implying a potential long-term reduction in musculoskeletal disorders. Results also underscore the potential importance of the index finger in detecting calculus and tooth surface irregularities. It was concluded that tactile sensitivity decreases with hand-activated scaling and increases with ultrasonic scaling over a 45-minute period. Short term vibration exposure from the ultrasonic scaler is insufficient to negatively affect tactile sensitivity. The long term effects of scaling with hand-activated and mechanized instruments on tactile sensitivity warrants further testing on clients in a clinical setting

Capsaicin-sensitive cutaneous primary afferents convey electrically induced itch in humans

Specially designed transcutaneous electrical stimulation paradigms can be used to provoke experimental itch. However, it is unclear which primary afferent fibers are activated and whether they represent pathophysiologically relevant, C-fiber mediated itch. Since low-threshold mechano-receptors have recently been implicated in pruriception we aimed to characterize the peripheral primary afferent subpopulation conveying electrically evoked itch in humans (50 Hz stimulation, 100 μs square pulses, stimulus-response function to graded stimulus intensity). In 10 healthy male volunteers a placebo-controlled, 24-h 8% topical capsaicin-induced defunctionalization of capsaicin-sensitive (transient receptor potential V1-positive, ‘TRPV1’+) cutaneous fibers was performed. Histaminergic itch (1% solution introduced by a prick test lancet) was provoked as a positive control condition. Capsaicin pretreatment induced profound loss of warmth and heat pain sensitivity (pain threshold and supra-threshold ratings) as assessed by quantitative sensory testing, indicative of efficient TRPV1-fiber defunctionalization (all outcomes: P 0.0001). The topical capsaicin robustly, and with similar efficaciousness, inhibited itch intensity evoked by electrical stimulation and histamine (−89 ± 4.1% and −78 ± 4.9%, respectively, both: P 0.0001 compared to the placebo patch area). The predominant primary afferent substrate for electrically evoked itch in humans, using the presently applied stimulation paradigm, is concluded to be capsaicin-sensitive polymodal C-fibers.FSW - Self-regulation models for health behavior and psychopathology - ou

Facial expressions of pain: the role of the serotonergic system

Rationale Although interest in the neurobiology of facial communication of pain has increased over the last decades, little is known about which neurotransmitter systems might be involved in regulating facial expressions of pain. Objectives We aim to investigate whether the serotonergic system (5-HT), which has been implicated in various aspects of pain processing as well as in behavioral response inhibition, might play a role in facial expressions of pain. Using acute tryptophan depletion (ATD) to manipulate 5-HT function, we examined its effects on facial and subjective pain responses. Methods In a double-blind, placebo-controlled within-subject design, 27 participants received either an ATD or a control drink in two separate sessions. Approximately 5-h post-oral consumption, we assessed pain thresholds (heat, pressure) as well as facial and subjective responses to phasic heat pain. Moreover, situational pain catastrophizing and mood were assessed as affective state indicators. Results ATD neither influenced pain thresholds nor self-report ratings, nor catastrophizing or mood. Only facial responses were significantly affected by ATD. ATD led to a decrease in pain-indicative as well as in pain-non-indicative facial responses to painful heat, compared to the control condition. Conclusions Decrease in brain 5-HT synthesis via ATD significantly reduced facial responses to phasic heat pain; possibly due to (i) diminished disposition to display social behavior or due to (ii) decreased facilitation of excitatory inputs to the facial motor neuron

Magnetic Field Effects On The Neuroprocessing Of Pain

Magnetic fields can affect behaviour in a variety of ways, in a manner that is dependent on the particulars of the magnetic field exposure. A specific pulsed magnetic field with analgesic properties was investigated using functional magnetic resonance imaging with acute thermal pain. The functional activation of pain was significantly different pre/post exposure vs. a sham condition within areas of the brain associated with the affective component of pain, in particular the anterior cingulate and the right insula. Sleep was found to be a significant confound with a 45-minute exposure. This was the first time fMRI has been used as a tool to investigate bioelectromagnetics effects, and demonstrates that an MR system can be used for both image acquisition and exposure. This technique will have applications to functional tasks beyond the acute thermal pain tested here

SDEC Audit. Progetto per la verifica applicativa dello Schema di Sviluppo dello Spazio Europeo attraverso reti interistituzionali nell'ambito di Interreg III. Rapporto finale

Rapporto operativo per il Ministero dei lavori pubblic

Acceptance Versus Distraction As Coping Strategies for Acute Pain and Pain-induced Alcohol Urge and Approach Inclinations

Excessive alcohol use is a leading cause of preventable death and disproportionately affects people with pain. Experimental research has identified pain as a determinant of alcohol use proxies that has its influence via negative affect (i.e. mediation effect). Although experimental research has shown that acceptance coping reduces pain-related negative affect, such effects have not been examined within the context of the pain and alcohol relationship. The purpose of this study was to test acceptance coping (vs. distraction) as a moderator of the previously established mediation model. Based on a randomized 2x2 between-subjects repeated-measures experimental design, pain-free hazardous drinkers (N = 135) were randomly assigned to receive acceptance or distraction coping training. They were asked to use the strategy while receiving a painful or non-painful acute stimulus. It was hypothesized that the effects of pain condition on negative affect would be weaker among those who received acceptance training, which would, in turn, result in lower ratings on alcohol use proxy measures vs. those receiving distraction. The indirect effects of coping condition were non-significant and there were no pain condition X coping condition effects on negative affect. Given this, the moderator was removed, and a simple mediation model was tested. Results showed significant indirect effects for alcohol urge through negative affect. Pain condition predicted increases in negative affect, but negative affect did not effect alcohol use proxies. Results suggest that there are no differences between acceptance and distraction coping in ameliorating the effects of acute pain on negative affect and alcohol use proxies. The previous mediation model was partially replicated. Findings provide information that may accelerate the design of interventions to curtail drinking for pain-coping by better understanding the utility of acceptance training and the pain and alcohol relation

Digital library activities in Germany: the German Digital Library Program GLOBAL INFO

"Several digital library projects have emerged in Germany in recent years. The German Digital Library Programme GLOBAL INFO, which is funded by the federal ministry for education and research from 1998 to 2003, is about to become the most important of them. It has the aim to ad-vance for the single scientist 'optimal access to the world-wide electronic and multimedial information on full texts, literature references, factual databases and software' at every workdesk. The programme requests the close cooperation between all the parties taking part in the processes of provision of information and documents. A first wave of projects has recently started. Their areas of concern are tools and standards in the production of documents (along the publication chain), description and retrieval of documents and dealing with their heterogeneity (i.e. metadata and retrieval, distributed systems), and provision and payment systems for published documents in distributed systems. Some more projects in other fields (dynamic documents, large distributed systems, administration systems for users and integration of electronic business models and payment systems) have been or will be handed in and evaluated in the course of 1999." (author's abstract

Neuronal and behavioural pain processing

In our study “Neuronal and Behavioural Pain Processing: A Comparison Between a Strong Brand and a Generic Medication Placebo using the Example of Aspirin vs. 1A Pharma”, we investigated the expectation effects associated with brands by labelling two different placebo interventions. We tested the hypothesis, whether a strong brand can influence the impact of an inert substance. We studied the potential differences between the two placebos on a behavioural and neural level inducing the stimulus with noxious heat pain using Medoc. The research objective was to unveil, whether recipients can be influenced through expectations, verbal suggestions and the brand itself. We applied a two by two design with two identical placebo interventions that differed in their labelling. One group was told that they will receive 500 mg of “Aspirin” (original brand), while the other group was told that they will receive a popular ASA generic (“1A Pharma”). At the beginning, we established the individual pain levels of each subject with the numeric rating scale. Then we measured pain intensities before and after the intervention. The intervention was the administration of the placebo. We investigated behavioural as well as neural differences and looked for corresponding activated brain regions using functional magnetic resonance imaging (fMRI). Those participants, who were administered the original brand in the placebo intervention, showed a decrease in pain intensity. The generic group did not show any significant pain decrease. At the neuronal level, during the native condition, we observed activations of the anterior insula in both groups. After the intervention, the participants showed activations of the dorsomedial prefrontal cortex. The direct comparison of the two placebo conditions – the branded placebo vs. the generic – showed higher activations for the bilateral dorsolateral and dorsomedial prefrontal cortex. During the anticipation phase we observed activations of hippocampal, parahippocampal and adjacent brain areas for the generic group, only. These results suggest that only the original brand appears to evoke a behavioural response measured in terms of pain reduction. On a neuronal level, the activations were significant for the original brand only. Comparing the two placebo interventions, expectations seem to be significantly enhanced by the trusted brand, which appears to boost the placebo effect. Our results suggest that the underlying neural mechanisms of this placebo response are based on fronto-cortical neural networks