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In vitro biocompatibility of nickel-titanium esthetic orthodontic archwires
No full textObjective: To investigate the cytotoxicity of nickel-titanium (NiTi) esthetic orthodontic archwires
with different surface coatings.
Materials and Methods: Three fully coated, tooth-colored NiTi wires (BioCosmetic, Titanol
Cosmetic, EverWhite), two ion-implanted wires (TMA Purple, Sentalloy High Aesthetic), five
uncoated NiTi wires (BioStarter, BioTorque, Titanol Superelastic, Memory Wire Superelastic, and
Sentalloy), one b-titanium wire (TMA), and one stainless steel wire (Stainless Steel) were
considered for this study. The wire samples were placed at 37uC in airtight test tubes containing
Dulbecco’s Modified Eagle’s Medium (0.1 mg/mL) for 1, 7, 14, and 30 days. The cell viability of
human gingival fibroblasts (HGFs) cultured with this medium was assessed by the 3-(4,5-
dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Data were analyzed by a twoway analysis of variance (a 5 .05).
Results: The highest cytotoxic effect was reached on day 30 for all samples. The archwires
exhibited a cytotoxicity on HGFs ranging from “none” to “slight,” with the exception of the
BioTorque, which resulted in moderate cytotoxicity on day 30. Significant differences were found
between esthetic archwires and their uncoated pairs only for BioCosmetic (P 5 .001) and
EverWhite (P , .001).
Conclusions: Under the experimental conditions, all of the NiTi esthetic archwires resulted in
slight cytotoxicity, as did the respective uncoated wires. For this reason their clinical use may be
considered to have similar risks to the uncoated archwires. (Angle Orthod. 0000;00:000–000.
Association between psychological traits and occlusal tactile acuity of healthy individuals
No full textObjectives: Tactile acuity is a somatosensory measure of the extent to which humans can discern tactile stimuli. It is influenced by how peripheral signals are processed centrally. In the oral cavity, Occlusal Tactile Acuity (OTA) is the ability to perceive minimal thicknesses between antagonist teeth. The aim of the current study was to assess the association between psychological traits and OTA of otherwise healthy individuals. Methods: Sixty-three volunteers (32 males; mean age ± SD: 24.6 ± 2.7 years) participated in this study. Somatosensory amplification, anxiety, depression, physical symptoms and pain catastrophizing were scored using questionnaires, and subgroups of severity were created per variable based on cut-offs. OTA was measured using 9 aluminium foils with thickness (ranging from 8 to 72 μm) and one sham test (without foil). Each thickness was tested 10 times in random order, the participants were instructed to report whether they felt the foil between their molars and the mean percentage of correct answers was computed. A linear mixed model was used with OTA as a dependent variable and psychological domain as an independent variable. Results: Significantly different OTA was observed among the anxiety subgroups (p =.003), supporting a decreased perception of thicknesses 24 and 32 μm (p =.018 and p <.001, respectively) in participants with moderate/severe anxiety compared to those with no/mild anxiety. Significantly different OTA was also observed among the pain catastrophizing subgroups (p =.008), showing decreased perception of thicknesses 32 and 40 μm (p <.001 and p =.007, respectively) in severe catastrophizing levels, compared to no/mild catastrophizing levels. No significant differences were observed for the other variables. Conclusions: Healthy adults with increased anxiety or pain catastrophizing levels show decreased interdental acuity as compared to participants with minor or no psychological impairment.</p
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
Translation and validation of the italian version of the Psychosocial Impact of Dental Aesthetics Questionnaire (pidaq) among adolescents
No full textThe Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) is a valid tool aiming to evaluate the self-reported influence of dental aesthetics on quality of life. This questionnaire was developed in English for young adults, and later translated and validated with an Italian population. A new version of the questionnaire was recently introduced to be used in adolescents (11-17 years- old), but it had not been translated in Italian yet. Hence, the purpose of this study was to translate, cross-culturally adapt and validate the PIDAQ for adolescents, for its use among Italian subjects
Class II functional orthopaedic treatment: a systematic review of systematic reviews
No full textThis Systematic Review (SR) aims to assess the quality of SRs and Meta-Analyses (MAs) on functional orthopaedic treatment of Class II malocclusion and to summarise and rate the reported effects. Electronic and manual searches were conducted until June 2014. SRs and MAs focusing on the effects of functional orthopaedic treatment of Class II malocclusion in growing patients were included. The methodological quality of the included papers was assessed using the AMSTAR (Assessment of Multiple Systematic Reviews). The design of the primary studies included in each SR was assessed with Level of Research Design scoring. The evidence of the main outcomes was summarised and rated according to a scale of statements. 14 SRs fulfilled the inclusion criteria. The appliances evaluated were as follows: Activator (2 studies), Twin Block (4 studies), headgear (3 studies), Herbst (2 studies), Jasper Jumper (1 study), Bionator (1 study) and Fränkel-2 (1 study). Four studies reviewed several functional appliances, as a group. The mean AMSTAR score was 6 (ranged 2-10). Six SRs included only controlled clinical trials (CCTs), three SRs included only randomised controlled trials (RCTs), four SRs included both CCTs and RCTs and one SR included also expert opinions. There was some evidence of reduction of the overjet, with different appliances except from headgear; there was some evidence of small maxillary growth restrain with Twin Block and headgear; there was some evidence of elongation of mandibular length, but the clinical relevance of this results is still questionable; there was insufficient evidence to determine an effect on soft tissues
Dental and skeletal effects of palatal expansion techniques: a systematic review of the current evidence from systematic reviews and meta-analyses
No full textThe aim was to assess the quality and to summarise the findings of the Systematic Reviews (SRs) and Meta-Analyses (MAs) on the dental and skeletal effects of maxillary expansion. Electronic and manual searches have been independently conducted by two investigators, up to February 2015. SRs and MAs on the dentoalveolar and skeletal effects of fixed expanders were included. The methodological quality was assessed using the AMSTAR (A Measurement Tool to Assess Systematic Reviews). The design of the primary studies included in each SR/MA was assessed with the LRD (Level of Research Design scoring). The evidence for each outcome was rated applying a pre-determined scale. Twelve SRs/MAs were included. The AMSTAR scores ranged from 4 to 10. Two SRs/MAs included only RCTs. The current findings from SRs/MAs support with high evidence a significant increase in the short-term of maxillary dentoalveolar transversal dimensions after Rapid Maxillary Expansion (RME). The same effect is reported with moderate evidence after Slow Maxillary Expansion (SME). However, there is moderate evidence of a non-significant difference between the two expansion modalities concerning the short-term dentoalveolar effects. With both RME and SME, significant increase of skeletal transversal dimension in the short-term is reported, and the skeletal expansion is always smaller than the dentoalveolar. Even though dental relapse to some extent is present, long-term results of the dentoalveolar effects show an increase of the transversal dimension, supported by moderate evidence for RME and low evidence for SME. Skeletal long-term effects are reported only with RME, supported by very low evidence
Cross-cultural adaptation and validation of the Italian Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ)
No full textPurpose To validate and cross-culturally adapt the Italian
version of the Psychological Impact of Dental Aesthetics
Questionnaire (PIDAQ) among Italian young adults.
Methods After translation, back translation, and crosscultural adaptation of the English PIDAQ, a first version of
the Italian questionnaire was pretested. The final Italian
PIDAQ was administered to 598 subjects aged
18–30 years, along with two other instruments: the aesthetic component of the index of orthodontic treatment
need (IOTN-AC) and the perception of occlusion scale
(POS), which identified the self-reporting grade of malocclusion. Structural validity was assessed by means of factorial analysis, internal consistency was measured with
Cronbach’s alpha coefficient (a), convergent validity was
assessed by means of Spearman correlation, and test–retest
reliability was calculated with intra-class correlation
coefficient (ICC) and standard measurement error.
Criterion validity was evaluated by multivariate and univariate analysis of variance with Bonferroni post hoc tests.
Results The a of the Italian PIDAQ domains ranged
between 0.79 and 0.92. The ICC was between 0.81 and
0.90. The mean scores of each PIDAQ domain showed a
statistically significant difference when analysed according
to the IOTN-AC and POS scores.
Conclusion The satisfactory psychometric properties make PIDAQ a usable tool for future studies on oral healthrelated quality of life among Italian young adults
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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