Johan Hoogstraten

Innate secretory immunity in response to laboratory stressors that evoke distinct patterns of cardiac autonomic activity

Objective Most infections begin at mucosal surfaces. These surfaces are covered by the secretory proteins of the exocrine glands (eg, the salivary, respiratory, and gastrointestinal glands), which provide a first line of innate defense. The release of these secretory proteins is under neuroendocrine control and thus, in theory, sensitive to modulation by psychosocial stress. This was empirically tested by measuring the salivary secretion of cystatin S, lactoferrin, &agr;-amylase, the mucins MUC5B and MUC7, and total salivary protein in response to stressors known to evoke distinct patterns of cardiac autonomic activity. Methods Thirty-two undergraduate volunteers were each subjected to two laboratory stressors and a control condition. Stressors were an active coping memory test and a passive coping video presentation showing surgical procedures. In the control condition participants viewed a didactic video presentation. Results The stressors evoked the expected distinct patterns of cardiac autonomic activity. The memory test produced a strong increase in sympathetic activity (evidenced by a shortened preejection period), and a decrease in cardiac parasympathetic activity (evidenced by a decrease in heart rate variability). This active coping response was associated with an enhanced secretion (&mgr;g/min, controlling for salivary flow rate) of MUC7, lactoferrin, &agr;-amylase, and total salivary protein. Conversely, the surgical video produced an increase in cardiac vagal tone and a modest increase in sympathetic activity. This passive coping response was associated with an enhanced secretion of all proteins studied. These secretory responses were generally larger than the secretory responses during the active coping memory test. Correlation analyses indicated that for both stressors autonomic and cardiovascular reactivity was positively associated with an enhanced and prolonged secretory activity. Conclusions Stress-induced modulation of innate secretory immunity may be a contributing factor in the observed relationship between stress and susceptibility to infectious diseases. We further propose a more differentiated approach to acute stress by distinguishing among stressors with distinct autonomic nervous system effects.

Psychological stress as a determinant of protein levels and salivary-induced aggregation of Streptococcus gordonii in human whole saliva

Several pathologies of the oral cavity have been associated with stress, so we investigated salivary-induced aggregation during psychological stress. In addition, salivary total protein, alpha-amylase, and secretory immunoglobulin A (s-IgA) were assessed. In this longitudinal study, 28 dental students provided unstimulated whole saliva during 10 minutes before an academic examination and subsequently 2 weeks and 6 weeks later in a nonstress situation. The effect of whole saliva on the aggregation of Streptococcus gordonii (HG 222) was determined spectrophotometrically. The results show a significant stress-mediated increase of salivary total protein concentration, alpha-amylase activity, amylase/protein ratio, alpha-amylase output, s-IgA concentration, and s-IgA output. There was also a trend for increased total protein output, whereas salivary flow rate was unchanged. The aggregation of S. gordonii in whole saliva collected before examination was 13.1%, whereas the aggregation in whole saliva collected during nonstress was 23.3%. This reduction was statistically significant (p <.01). Furthermore, the decrease in bacterial aggregation was related to the increase in state-anxiety (p <.05). The reduction in aggregation of S. gordonii under stress was not correlated with changes in salivary flow rate, s-IgA concentration, total protein concentration, or alpha-amylase activity. These results suggest that acute psychological stress exerts its influence on both salivary composition and salivary function. Reduced bacterial aggregation may be a contributing factor in the often reported relationship between stress and impaired oral health.

Academic Self-Efficacy and Malleability of Relevant Capabilities as Predictors of Exam Performance

In accordance with Wood and Lockes (1987) findings, the 1st study was based on the prediction that academic self-efficacy (ASE) and personal goals of psychology freshmen (N = 438) would contribute to exam performance. Although the results supported this prediction, they were less strong than those of Wood and Locke. The timing of the ASE measurement appeared to be relevant. In the 2nd study, the authors predicted that self-efficacy appraisals, together with beliefs con cerning the malleability of ability, would influence exam performance and the attri bution of failure to lack of talent. The participants with high self-efficacy appraisals and strong malleability beliefs ascribed failure less to lack of talent than those with low self-efficacy appraisals and weak malleability beliefs did. This difference occurred between participants with high and low intelligence. Differences between the exam scores occurred only in the high-intelligence group: The exam performance of the participants with high self-efficacy appraisals and strong malleability beliefs was better than that of the participants with low self-efficacy appraisals and weak malleability beliefs.

Experience with Dental Pain and Fear of Dental Pain

Anxious people tend to overestimate the intensity of aversive events such as fear and pain. When an aversive event has been experienced personally, prediction is based on experience and is possibly less subject to bias due to anxiety. Therefore, it was hypothesized that subjects will overestimate fear of specific dental pains relative to subjects who experienced the pain or procedure personally. Samples of highly anxious dental patients (n = 48), patients waiting for periodontal treatment (n = 56), and psychology freshmen (n = 262) completed a measure of dental anxiety and the Fear of Dental Pain (FDP) questionnaire. All FDP items were extended with the question whether the subject ever experienced the pain personally (yes or no). Less fear was reported when the pain had been experienced personally, with the exception of the sample of highly anxious dental patients. The results suggest that fear of dental pain is a highly important covariate in dental pain research.

Dental management of patients using antithrombotic drugs: critical appraisal of existing guidelines

OBJECTIVES The aims were: 1) to identify the guidelines available for management of dental invasive procedures in patients on antithrombotic drugs; 2) to assess their quality with the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument; and 3) to summarize their conclusions and recommendations. STUDY DESIGN Systematic literature search for guidelines in several electronic databases. Retrieved guidelines were evaluated with the AGREE instrument for quality assessment. RESULTS The systematic search yielded 93 results, of which only 4 were evidence-based practice guidelines. Two of these guidelines could be recommended for clinical use on the basis of the AGREE instrument. These 2 guidelines drew 68 conclusions from the existing literature and provided 58 recommendations. CONCLUSIONS Two evidence-based clinical practice guidelines, satisfactorily fulfilling the criteria of the AGREE instrument and both published in 2007, advise to not routinely discontinue antiplatelet and anticoagulation medication before dental surgery. The majority of the recommendations, however, were not sufficiently linked to levels of evidence.

Effect of Feedback on Base-Rate Utilization

The effect of direct training with feedback on a base-rate problem of the engineers-lawyers type is assessed. Analysis indicates that feedback leads to adjusted probability estimates closer to the Bayesian norm than those in the no-feedback training-only condition. For a second base-rate problem (the so called “divorce problem”), however, no effect of training was shown, even though thinking-aloud protocols for this problem showed that subjects mentioned base-rates more often in the feedback than in the no-treatment condition.

Young children's oral health-related quality of life and dental fear after treatment under general anaesthesia: a randomized controlled trial

During the past decade the research interest in Oral Health-Related Quality of Life (OHRQoL) has been prospering. This study was performed to test (using a randomized controlled trial design) the hypothesis that young childrens OHRQoL improves after oral rehabilitation under general anaesthesia (GA). A further aim of this study was to explore whether dental fear also changes. One-hundred and four children (54 boys; mean age 4.08 yr, standard deviation = 1.09), who had been referred to a specialized clinic in paediatric dentistry, were randomly assigned, based on a Solomon four-group design, to two treatment (GA) and two control conditions. The Early Childhood Oral Health Impact Scale (ECOHIS) and the Childrens Fear Survey Schedule-Dental Subscale (CFSS-DS) were used to assess OHRQoL and dental fear, respectively, before and after the rehabilitation procedures. A 2 x 2 analysis of variance revealed that the total ECOHIS score after GA was more positive in the GA group than in the control group. There was no effect found of the pre-test and there was also no interaction between the pre-test and treatment. In the total CFSS-DS scores no effects were found. The results of this study showed that the childs OHRQoL improved after treatment under GA. Furthermore, children need guidance in reducing dental fear after treatment under GA.

Factorial validity of the Maslach burnout inventory - Dutch version (MBI-NL) among dentists

Burnout is considered to be a long-term reaction to occupational stress. It is characterized by emotional exhaustion, depersonalization, and diminished personal accomplishment. The most widely used instrument to measure burnout is the Maslach Burnout Inventory (MBI), developed by Maslach and Jackson (1986). From this instrument, Schaufeli and van Dierendonck (1995a) developed a somewhat modified Dutch version: the MBI-NL. Burnout among dentists has hardly been studied. Since the professions that the MBI-NL was developed upon are quite different from dentistry, the aim of this study was to test the three-factor structure of the MBI-NL against alternative structures among dentists. Both principal components analysis (PCA) and confirmatory factor analysis (CFA) were examined in a representative sample of 709 Dutch general dental practitioners (75 per cent response rate). The three-factor structure shows the best fit to the underlying data, while other psychometric qualities are very satisfactory. It is concluded that the three-factor structure of the MBI-NL is superior to alternative structures, and that the MBI-NL is a highly suitable instrument to measure burnout among dentists. Copyright

Treatment outcome with implant-retained overdentures: Part I—Clinical findings and predictability of clinical treatment outcome

This nationwide study was conducted to clinically evaluate treatment with implant-retained overdentures when applied on a large scale and to determine to what degree treatment results could be predicted from patient and treatment characteristics at baseline. A total of 429 patients who had received implant overdenture treatment were clinically investigated by two dentists. Implant survival was high, especially for implants placed in the mandible. Results for the maxilla appeared far less promising. Complications that were observed predominantly concerned inflammation of the peri-implant tissues and poor oral hygiene. The quality of the overdentures, as assessed on three conventional prosthetic parameters, was generally good. Nevertheless, overdentures on oral implants appear to require considerable maintenance. No statistically significant correlation could be found between patient and treatment characteristics at baseline and the clinical treatment outcome. So, although treatment outcome with implant-retained overdentures appeared favorable, clinical results were not individually predictable.

Assessment of dental anxiety: A facet approach

Abstract Dental anxiety is a complicated phenomenon, and its multicomponent nature is often not acknowledged in existing measurement instruments. Using a facet design, a new Dental Anxiety Inventory (DAI) was constructed. Facets chosen were: time (made up of four elements: at home, on your way to the denstist, in the denstists waiting room, in the dental chair), situation (three elements: introductory aspects, dentist-patient interaction, actual dental treatment), and reaction (three elements: subjective feelings, physical reactions, cognitive reactions). Psychometric qualities of the DAI are good. The internal structure of the DAI was studied by linear and nonlinear techniques, and was partially recovered from the data. The construct and criterion validity of the DAI was supported in several studies.