Abstract
Background
Post-traumatic stress disorder (PTSD) sufferers show problematic patterns of Internet use such as fear of missing out (FOMO) and sharing misinformation and fake news. This study ...aimed to investigate these associations in survivors of the 2008 earthquake in Wenchuan, China.
Methods
A self-reported survey was completed by 356 survivors of the Wenchuan earthquake. A mediated structural equation model was constructed to test a proposed pattern of associations with FOMO as a mediator of the relationship between PTSD symptoms and belief in fake news, as well as moderators of this pathway.
Results
PTSD was directly associated with believing fake news (β = 0.444, p < .001) and with FOMO (β = 0.347, p < .001). FOMO mediated the association between PTSD and fake news belief (β = 0.373, p < .001). Age moderated the direct (β = 0.148, t = 3.097, p = .002) and indirect (β = 0.145, t = 3.122, p = .002) pathways, with effects more pronounced with increasing age. Gender was also a moderator, with the indirect effect present in females but not in males (β = 0.281, t = 6.737, p < .001).
Conclusion
Those with higher PTSD symptoms are more likely to believe fake news and this is partly explained by FOMO. This effect is present in females and not males and is stronger in older people. Findings extend knowledge of the role of psychological variables in problematic Internet use among those with PTSD.
Three-dimensional (3D) bioprinting, a method derived from additive manufacturing technology, is a recent and ongoing trend for the construction of 3D volumetric structures. The purpose of this ...systematic review is to summarize evidence from existing human and animal studies assessing the application of 3D printing on bone repair and regeneration in the craniofacial region.
A rigorous search of all relevant clinical trials and case series was performed, based on specific inclusion and exclusion criteria. The search was conducted in all available electronic databases and sources, supplemented by a manual search, in December 2017.
43 articles (6 human and 37 animal studies) fulfilled the criteria. The human studies included totally 81 patients with craniofacial bone defects. Titanium or hydroxylapatite scaffolds were most commonly implanted. The follow-up period ranged between 6 and 24 months. Bone repair was reported successful in nearly every case, with minimal complications. Also, animal intervention studies used biomaterials and cells in various combination, offering insights into the techniques, through histological, biochemical, histomorphometric and microcomputed tomographic findings. The results in both humans and animals, though promising, are yet to be verified for clinical impact.
Future research should be focused on well-designed clinical trials to confirm the short- and long- term efficacy of 3D printing strategies for craniofacial bone repair.
Emerging 3D printing technology opens a new era for tissue engineering. Humans and animals on application of 3D printing for craniofacial bone repair showed promising results which will lead clinicians to investigate more thoroughly alternative therapeutic methods for craniofacial bone defects.
Abstract The aim of this study was to evaluate the accuracy and reliability of standard anthropometric linear measurements made with three different three-dimensional scanning systems namely laser ...surface scanning (Minolta Vivid 900), cone beam computed tomography (CBCT), 3D stereo-photogrammetry (Di3D system) and to compare them to physical linear measurements. The study sample consisted of seven cadaver heads. The reliability and accuracy were assessed by means of a series of 21 standardized, linear facial measurements derived from 15 landmarks taken both directly on the face with a set of digital callipers and indirectly from a three-dimensional (3D) soft tissue surface models derived from CBCT, laser surface scans and 3D photographs. Statistical analysis for the reliability was done by means of intraclass correlation coefficients (ICCs). Accuracy was determined by means of the absolute error (AE) and absolute percentage error (APE) by comparison of the 3D measurements to the physical anthropometrical measurements. All the 3D scanning systems were proved to be very reliable (ICC > 0.923–0.999) when compared to the physical measurements (ICC; 0.964–0.999). Only one CBCT measurement (t-g) and one Di3D measurement (t-sn left) had a mean AE of more than 1.5 mm. There are clear potential benefits of using 3D measurements appose to direct measurements in the assessment of facial deformities. Measurements recorded by the three 3D systems appeared to be both sufficiently accurate and reliable enough for research and clinical use.
Tooth or material wear in a dentition is a common finding that requires timely diagnosis for management and prevention of further loss or associated esthetic or functional impairment. Various ...qualitative and quantitative methods have been suggested to measure tooth or material wear, but they present with limitations, such as imprecision, subjectivity, or high complexity. Here we developed and assessed an efficient 3D superimposition method to accurately measure occlusal tooth wear on 3D digital dental models. For this purpose, teeth on plaster casts were manually grinded on their occlusal surfaces to simulate various degrees of tooth wear. The casts were scanned using a surface scanner. Grinded tooth crowns (T1) were segmented and compared to the original crowns (T0) using five 3D surface superimposition techniques and a gold standard technique (GS). GS measurements were obtained by using intact adjacent structures as superimposition references. The technique of choice (complete crown with 30% estimated overlap of meshes) showed the best reproducibility (maximum difference < 0.050 mm
) and excellent agreement with the GS technique (median difference: 0.032 mm
). The suggested 3D superimposition method offers a highly efficient and accurate tool for tooth wear assessment, which could be applicable to clinical conditions.
Bacterial infections are mostly due to bacteria in their biofilm mode‐of‐growth, making them recalcitrant to antibiotic penetration. In addition, the number of bacterial strains intrinsically ...resistant to available antibiotics is alarmingly growing. This study reports that micellar nanocarriers with a poly(ethylene glycol) shell fully penetrate staphylococcal biofilms due to their biological invisibility. However, when the shell is complemented with poly(β‐amino ester), these mixed‐shell micelles become positively charged in the low pH environment of a biofilm, allowing not only their penetration but also their accumulation in biofilms without being washed out, as do single‐shell micelles lacking the pH‐adaptive feature. Accordingly, bacterial killing of multidrug resistant staphylococcal biofilms exposed to protoporphyrin IX‐loaded mixed‐shell micelles and after light‐activation is superior compared with single‐shell micelles. Subcutaneous infections in mice, induced with vancomycin‐resistant, bioluminescent staphylococci can be eradicated by daily injection of photoactivatable protoporphyrin IX‐loaded, mixed‐shell micelles in the bloodstream and light‐activation at the infected site. Micelles, which are not degraded by bacterial enzymes in the biofilm, are degraded in the liver and spleen and cleared from the body through the kidneys. Thus, adaptive micellar nanocarriers loaded with light‐activatable antimicrobials constitute a much‐needed alternative to current antibiotic therapies.
Photodynamic treatment with protoporphyrin IX‐loaded micelles is successful in eradicating a subcutaneous, multidrug‐resistant infection in mice, while unused micelles are demonstrated to be cleared from the blood circuation.
Introduction The aim of this crossover study was to assess perceptions and preferences for impression techniques in young orthodontic patients receiving alginate and 2 different digital impressions. ...Methods Thirty-eight subjects aged 10 to 17 years requiring impressions for orthodontic treatment were randomly allocated to 3 groups that differed in the order that an alginate impressions and 2 different intraoral scanning procedures were administered. After each procedure, the patients were asked to score their perceptions on a 5-point Likert scale for gag reflex, queasiness, difficulty to breathe, uncomfortable feeling, perception of the scanning time, state of anxiety, and use of a powder, and to select the preferred impression system. Chairside time and maximal mouth opening were also registered. Results More queasiness ( P = 0.00) and discomfort ( P = 0.02) during alginate impression taking of the maxilla were perceived compared with the scans with the CEREC Omnicam (Sirona Dental Systems, Bensheim, Germany). There were no significant differences in perceptions between the alginate impressions and the Lava C.O.S. (3M ESPE, St Paul, Minn) and between the 2 scanners. Chairside times for the alginate impressions (9.7 ± 1.8 minutes) and the CEREC Omnicam (10.7 ± 1.8 minutes) were significantly lower ( P <0.001) than for the Lava C.O.S. (17.8 ± 4.0 minutes). Digital impressions were favored by 51% of the subjects, whereas 29% chose alginate impressions, and 20% had no preference. Regardless of the significant differences in the registered times among the 3 impression-taking methods, the distributions of the Likert scores of time perception and maximal mouth opening were similar in all 3 groups. Conclusions Young orthodontic patients preferred the digital impression techniques over the alginate method, although alginate impressions required the shortest chairside time.
Introduction Rapid prototyping is a fast-developing technique that might play a significant role in the eventual replacement of plaster dental models. The aim of this study was to investigate the ...accuracy and reproducibility of physical dental models reconstructed from digital data by several rapid prototyping techniques. Methods Twelve mandibular and maxillary conventional plaster models from randomly chosen subjects were selected and served as the gold standard. The plaster models were scanned to form high-resolution 3-dimensional surface models in .stl files. These files were converted into physical models using 3 rapid prototyping techniques: digital light processing, jetted photopolymer, and 3-dimensional printing. Linear measurements on the plaster models were compared with linear measurements on the rapid prototyping models. One observer measured the height and width of the clinical crowns of all teeth (first molar to first molar) on all models (plaster and replicas) using a digital caliper. All models were measured 5 times with a 2-week interval between measurements. Results The intraobserver agreement was high (intraclass correlation coefficient >0.94). The mean systematic differences for the measurements of the height of the clinical crowns were −0.02 mm for the jetted photopolymer models, 0.04 mm for the digital light processing models, and 0.25 mm for the 3-dimensional printing models. For the width of the teeth, the mean systematic differences were −0.08 mm for the jetted photopolymer models, −0.05 mm for the digital light processing models, and −0.05 mm for the 3-dimensional printing models. Conclusions Dental models reconstructed by the tested rapid prototyping techniques are considered clinically acceptable in terms of accuracy and reproducibility and might be appropriate for selected applications in orthodontics.
Many nanotechnology-based antimicrobials and antimicrobial-delivery-systems have been developed over the past decades with the aim to provide alternatives to antibiotic treatment of ...infectious-biofilms across the human body. Antimicrobials can be loaded into nanocarriers to protect them against de-activation, and to reduce their toxicity and potential, harmful side-effects. Moreover, antimicrobial nanocarriers such as micelles, can be equipped with stealth and pH-responsive features that allow self-targeting and accumulation in infectious-biofilms at high concentrations. Micellar and liposomal nanocarriers differ in hydrophilicity of their outer-surface and inner-core. Micelles are self-assembled, spherical core-shell structures composed of single layers of surfactants, with hydrophilic head-groups and hydrophobic tail-groups pointing to the micellar core. Liposomes are composed of lipids, self-assembled into bilayers. The hydrophilic head of the lipids determines the surface properties of liposomes, while the hydrophobic tail, internal to the bilayer, determines the fluidity of liposomal-membranes. Therefore, whereas micelles can only be loaded with hydrophobic antimicrobials, hydrophilic antimicrobials can be encapsulated in the hydrophilic, aqueous core of liposomes and hydrophobic or amphiphilic antimicrobials can be inserted in the phospholipid bilayer. Nanotechnology-derived liposomes can be prepared with diameters <100-200 nm, required to prevent reticulo-endothelial rejection and allow penetration into infectious-biofilms. However, surface-functionalization of liposomes is considerably more difficult than of micelles, which explains while self-targeting, pH-responsive liposomes that find their way through the blood circulation toward infectious-biofilms are still challenging to prepare. Equally, development of liposomes that penetrate over the entire thickness of biofilms to provide deep killing of biofilm inhabitants still provides a challenge. The liposomal phospholipid bilayer easily fuses with bacterial cell membranes to release high antimicrobial-doses directly inside bacteria. Arguably, protection against de-activation of antibiotics in liposomal nanocarriers and their fusogenicity constitute the biggest advantage of liposomal antimicrobial carriers over antimicrobials free in solution. Many Gram-negative and Gram-positive bacterial strains, resistant to specific antibiotics, have been demonstrated to be susceptible to these antibiotics when encapsulated in liposomal nanocarriers. Recently, also progress has been made concerning large-scale production and long-term storage of liposomes. Therewith, the remaining challenges to develop self-targeting liposomes that penetrate, accumulate and kill deeply in infectious-biofilms remain worthwhile to pursue.
Introduction Corticotomy and dental distraction have been proposed as effective and safe methods to shorten orthodontic treatment duration in adolescent and adult patients. A systematic review was ...performed to evaluate the evidence supporting these claims. Methods PubMed, Embase, and Cochrane databases were searched until April 2013 for randomized controlled trials, controlled clinical trials, and case series with 5 or more subjects that focused on velocity of tooth movement, reduction of treatment duration, or complications with various surgical protocols. There were no language restrictions during the search phase. Publications were systematically assessed for eligibility, and 2 observers graded the methodologic quality of the included studies with a predefined scoring system. Results Eighteen articles met the inclusion criteria. Seven studies were clinical trials, with small investigated groups. Only studies of moderate and low values of evidence were found. Surgically facilitated treatment was indicated for various clinical problems. All publications reported temporarily accelerated tooth movement after surgery. No deleterious effects on the periodontium, no vitality loss, and no severe root resorption were found in any studies. However, the level of evidence to support these findings is limited owing to shortcomings in research methodologies and small treated groups. No research concerning long-term stability could be included. Conclusions Evidence based on the currently available studies of low-to-moderate quality showed that surgically facilitated orthodontics seems to be safe for the oral tissues and is characterized by a temporary phase of accelerated tooth movement. This can effectively shorten the duration of orthodontic treatment. However, to date, no prospective studies have compared overall treatment time and treatment outcome with those of a control group. Well-conducted, prospective research is still needed to draw valid conclusions.
PDF
