1,720,963 research outputs found
An analysis of the visual behaviour of dental hygienist.
No full textThe visual behaviour of a dental hygienist is very critical: the practitioner is exposed to very high luminance levels, for long time doing heavy visual task with very small details, crucial colour perception and risk of damaging the patient condition in case of mistake.
A typical dental hygienist visual behaviour was deeply characterised in terms of relevant photometric quantities. The two most important quantities are: illuminance and luminace. In order to characterise the visual conditions of the practitioner luminance maps of his field of view were acquired with a luminance calibrated CCD (Charge Couple Device) detector.
The luminance maps showed high contrast zones that produce glare at the eyes of practitioner.
The contrast is the description of differences in luminance between an object and its background and is one of the two fundamental aspect for vision.
The team applied a procedure (2) based on CIE General Disability Glare Equation (3), to evaluate veiling luminance (a parameter describing the physiological origin of disability glare) that causes contrast degradation and visual fatigue, versus the degradation of Ratio of Contrast (Rc perceived contrast over intrinsic contrast).
This research demonstrated that the normative requirements are not sufficient to assure the best perceptive conditions for dental hygienist to prevent performances degradations and long-term fatigue
Favourably effective formulation of sodium iodide and salicylic acid plus professional hygiene in patients affected by desquamative gingivitis
No full textThe aim of this prospective pilot study was to evaluate the efficiency of an oral hygiene protocol, in combination with a solution of sodium iodide associated to salicylic acid (SISA), in patients affected by desquamative gingivitis (DG). Twenty patients not totally responding to conventional topical therapies, were selected. They received oral hygiene instructions with non-surgical periodontal therapy in a 21-day cohort study (during 3 weekly appointments). The SISA was used at the end of each session, with an impregnated gauze (with 5 ml of the solution) applied for 15 minutes for the upper jaw, and for a further 15 minutes with a new gauze for the lower. Evaluated clinical outcome variables included the full mouth plaque (FMPS) and bleeding (FMBS) scores, probing depth, patient related outcome and clinical gingival signs. Two months after concluding the planned protocol, a statistically significant reduction was observed for FMPS (P=0.032), FMBS (P=0.038), reported pain (P=0.000) and gingival clinical improvement (P=0.005). Topical application of SISA and professional oral hygiene procedures are connected with improvement of gum status, and decrease of related pain in subjects affected by severe DG
Ergonomic analysis of the handle of manual instruments for dental hygiene.
No full textWork-related musculoskeletal disorders of upper limbs are very common among dental hygienists. To minimize the risk of their occurrence, it is essential that attention be paid to proper ergonomics in the workplace, including the selection of instrumentation. At present there are no specific guidelines but only some indications for the selection of the different hand tools.
The main purpose of this study was to make a comparative analysis of different types of handles of hand tools used for root planing (Gracey curettes). Nine dental hygienists were interviewed with a questionnaire aimed to assess three different types of curette handle. The results showed that lightness, being
of solid steel, having a cylindrical non-uniform shape with full enlarged cross-section, and being silicon coated with non-slip ends are the preferred characteristics for a curette handle. These considerations may assist both manufacturers in designing new hand instruments and clinicians in selecting the most ergonomic ones to buy
The factors affecting visual discomfort of dental hygienist
Get PDFThe objectives of the paper were to analyze the visual behavior and visual discomfort parameters of dental practitioner at work, introducing the “lighting quality” approach in professional lighting using a suitable measurement methodology able to evaluate all relevant photometric and spectral parameters, not only the standard expected, and also the luminance map of the visual field. Spectral investigations are necessary to evaluate the damage potential of the lighting radiation while the luminance map allows the evaluation of sources of visual discomfort and disability. The “quality of lighting” is a new concept not yet considered in professional lighting but already recognized in road lighting standards. The paper provides also suggestions for new measurement methodology and lighting fixture design are provided and, for dental practitioners, recommendations about position and eye protection system to wear to improve visual comfort and minimize MSD, due to misplaced working position to avoid glar
Studio sulle condizioni di visione degli igienisti dentali.
No full textIl compito visivo dei professionisti dell’igiene dentale è particolarmente critico e delicato ed espone l’operatore a elevati livelli di illuminazione per periodi prolungati. Necessita quindi che sia svolto nelle migliori condizioni di illuminazione possibili tali da assicurare sia il confort dell’operatore che le migliori condizioni visive per minimizzare i rischi di errore.
Per assicurare questo è necessario che l’ambiente illuminato sia caratterizzato anche secondo parametri non strettamente normativi ma che diano un’effettiva indicazione delle reali condizioni di visione dell’igienista. La UNI EN ISO 9680:2008 prescrive le prestazioni meccaniche, elettriche e fotometriche del singolo apparecchio di illuminazione e non considera prestazioni a livello di impianto di illuminazione o di condizioni di visione dell’operatore. Il campo operatorio di una tipica postazione di lavoro di un igienista dentale è stato caratterizzato per le due grandezze più importanti ai fini dell’analisi delle condizioni di visione: illuminamento e luminanza (luminosità delle superfici o sorgenti presenti nel campo visivo dell’operatore). La misura della luminanza del campo visivo ha evidenziato che sono presenti alti livelli di luminanza che producono elevato abbagliamento. L’analisi delle mappe di luminanza ha dimostrato come la condizione di abbagliamento aumenti quando l’operatore indossa schermi di protezione oculari e nel caso di schermi particolarmente degradati superficialmente si perde la visione del dettaglio e un disco di abbagliamento è sovrapposto alla scena. Inoltre all’interno della bocca del paziente i livelli di luminanza del campo osservato sono così alti che il contrasto generato è vincolato solo a differenze di colore presenti tra le diverse superfici nel campo visivo. In conclusione possiamo affermare che il soddisfacimento degli attuali vincoli normativi non assicura che l’operatore possa operare nelle migliori condizioni di visione possibili
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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