Virtual Reality Relaxation to Decrease Dental Anxiety:Immediate Effect Randomized Clinical Trial

Introduction: Dental anxiety is common and causes symptomatic use of oral health services. Objectives: The aim was to study if a short-term virtual reality intervention reduced preoperative dental anxiety. Methods: A randomized controlled single-center trial was conducted with 2 parallel arms in a public oral health care unit: virtual reality relaxation (VRR) and treatment as usual (TAU). The VRR group received a 1- to 3.5-min 360° immersion video of a peaceful virtual landscape with audio features and sound supporting the experience. TAU groups remained seated for 3 min. Of the powered sample of 280 participants, 255 consented and had complete data. Total and secondary sex-specific mixed effects linear regression models were completed for posttest dental anxiety (Modified Dental Anxiety Scale [MDAS] total score) and its 2 factors (anticipatory and treatment-related dental anxiety) adjusted for baseline (pretest) MDAS total and factor scores and age, taking into account the effect of blocking. Results: Total and anticipatory dental anxiety decreased more in the VRR group than the TAU group (β = −0.75, P < .001, for MDAS total score; β = −0.43, P < .001, for anticipatory anxiety score) in patients of a primary dental care clinic. In women, dental anxiety decreased more in VRR than TAU for total MDAS score (β = −1.08, P < .001) and treatment-related dental anxiety (β = −0.597, P = .011). Anticipatory dental anxiety decreased more in VRR than TAU in both men (β = −0.217, P < .026) and women (β = −0.498, P < .001). Conclusion: Short application of VRR is both feasible and effective to reduce preoperative dental anxiety in public dental care settings (ClinicalTrials.gov NCT03993080). Knowledge Transfer Statement: Dental anxiety, which is a common problem, can be reduced with short application of virtual reality relaxation applied preoperatively in the waiting room. Findings of this study indicate that it is a feasible and effective procedure to help patients with dental anxiety in normal public dental care settings.Publisher PDFPeer reviewe

Palaeoecology of testate amoebae in a tropical peatland.

We present the first detailed analysis of subfossil testate amoebae from a tropical peatland. Testate amoebae were analysed in a 4-m peat core from western Amazonia (Peru) and a transfer function developed from the site was applied to reconstruct changes in water table over the past ca. 8,000 years. Testate amoebae were in very low abundance in the core, especially in the lower 125cm, due to a combination of poor preservation and obscuration by other organic matter. A modified preparation method enabled at least 50 testate amoebae to be counted in each core sample. The most abundant taxa preserved include Centropyxis aculeata, Hyalosphenia subflava, Phryganella acropodia and Trigonopyxis arcula. Centropyxis aculeata, an unambiguous wet indicator, is variably present and indicates several phases of near-surface water table. Our work shows that even degraded, low-abundance assemblages of testate amoebae can provide useful information regarding the long-term ecohydrological developmental history of tropical peatlands

Vegetation development in an Amazonian peatland

Recent investigations of wetlands in western Amazonia have revealed the presence of extensive peat deposits up to 7.5 m thick developing under a variety of vegetation types. We report the first attempt to establish the long-term (centennial to millennial scale) vegetation history of one of these peatland sites, Quistococha, a palm swamp close to Iquitos in northern Peru. Pollen and sedimentological analyses show that peat formation began at the core site under sedge fen or floating mat vegetation c. 2200 calendar years before present (cal yr BP). A seasonally flooded woodland developed c. 1880 cal yr BP. The permanently waterlogged palm swamp which persists today began to form c. 1000 cal yr BP, with the present vegetation community established by c. 400 years ago. The vegetation at this site has undergone continuous change throughout the period of peat formation, with several abrupt transitions, and reversals and repetitions in the apparent trajectory of change. The pollen data, combined with sedimentary evidence, suggest that the dominant control on ecosystem functioning and development is the flooding regime. There appears to have been a decrease in fluvial influence over time. There is no clear evidence of direct climatic or anthropogenic influence although we cannot rule out the possibility of climatically driven hydrological changes. Our results caution against adopting a simple model of peatland vegetation succession in this region. (C) 2013 Elsevier B.V. All rights reserved.</p