206 resultados para Dental extraction


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OBJECTIVES: Identify the words and phrases that authors used to describe time-to-event outcomes of dental treatments in patients.

MATERIALS AND METHODS: A systematic handsearch of 50 dental journals with the highest Citation Index for 2008 identified articles reporting dental treatment with time-to-event statistics (included "case" articles, n = 95), without time-to-event statistics (active "control" articles, n = 91), and all other articles (passive "control" articles n = 6796). The included and active controls were read, identifying 43 English words across the title, aim and abstract, indicating that outcomes were studied over time. Once identified, these words were sought within the 6796 passive controls. Words were divided into six groups. Differences in use of words were analyzed with Pearson's chi-square across these six groups, and the three locations (title, aim, and abstract).

RESULTS: In the abstracts, included articles used group 1 (statistical technique) and group 2 (statistical terms) more frequently than the active and passive controls (group 1: 35%, 2%, 0.37%, P < 0.001 and group 2: 31%, 1%, 0.06%, P < 0.001). The included and active controls used group 3 (quasi-statistical) equally, but significantly more often than the passive controls (82%, 78%, 3.21%, P < 0.001). In the aims, use of target words was similar for included and active controls, but less frequent for groups 1-4 in the passive controls (P < 0.001). In the title, group 2 (statistical techniques) and groups 3-5 (outcomes) were similar for included and active controls, but groups 2 and 3 were less frequent in the passive controls (P < 0.001). Significantly more included articles used group 6 words (stating the study duration) (54%, 30%, P = 0.001).

CONCLUSION: All included articles used time-to-event analyses, but two-thirds did not include words to highlight this in the abstract. There is great variation in the words authors used to describe dental time-to-event outcomes. Electronic identification of such articles would be inconsistent, with low sensitivity and specificity. Authors should improve the reporting quality. Journals should allow sufficient space in abstracts to summarize research, and not impose unrealistic word limits. Readers should be mindful of these problems when searching for relevant articles. Additional research is required in this field.

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The present invention relates to a novel class of water compatible molecularly imprinted polymers (AquaMIPs) capable of selectively binding target molecules such as riboflavin, or analogues thereof, in water or aqueous media, their synthesis and use thereof in food processing and extraction or separation processes.

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Glibenclamide (GLIB), an oral antidiabetic medication of the sulphonylurea drugs family, was stoichiometrically imprinted using tetrabutylammonium methacrylate as the functional monomer, for the first time in molecular imprinting, and utilising the sulphonylurea affinity for carboxylate anions. Solution association between the drug and the novel functional monomer was studied by 1H-NMR titrations, whereby evidence of sulphonylurea deprotonation followed by the formation of “narcissistic” GLIB dimers was found when tested in CDCl3, while an affinity constant in excess of 105 L mol-1 was measured in DMSO-d6. Detailed analysis of GLIB binding on the subsequently prepared imprinted and non-imprinted polymers confirmed deactivation of binding sites by exchange of a proton between GLIB and methacrylate, followed by extraction of the tetrabutylammonium counterion from the polymer matrix, resulting in overall reduced binding capacities and affinities by the imprinted material under equilibrium conditions. An optimised MI-SPE protocol, which included a binding site re-activation step, was developed for the extraction of GLIB from blood serum, whereby recoveries of up to 92.4% were obtained with exceptional sample clean-up.

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This paper uses the history of rubber extraction to explore competing attempts to control the forest environments of Assam and beyond in the second half of the nineteenth century. Forest communities faced rival efforts at environmental control from both European and Indian traders, as well as from various centres of authority within the Raj. Government attempts to regulate rubber collection were undermined by the weak authority of the Raj in these regions, leading to widespread smuggling. Partly in response to the disruptive influence of rubber traders on the frontier, the Raj began to restrict the presence of outsiders in tribal regions, which came to be understood as distinct areas outside British control. When rubber yields from the forests nearest the Brahmaputra fell in the wake of intensive exploitation, India's scientific foresters demanded and from 1870 obtained the ability to regulate the Assamese forests, blaming indigenous rubber tapping strategies for the declining yields and arguing that Indian rubber could be ‘equal [to] if not better' than Amazonian rubber if only tappers would change their practices. The knowledge of the scientific foresters was fundamentally flawed, however, and their efforts to establish a new type of tapping practice failed. By 1880, the government had largely abandoned attempts to regulate wild Indian rubber, though wild sources continued to dominate the supply of global rubber until after 1910.

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Objectives: Approximately 300 people are diagnosed with Head and Neck cancer annually in Northern Ireland. The management may include treatment by surgery or by chemotherapy and radiotherapy,
or a combination of modalities. Patients whose oral cavity, teeth, salivary glands and jaws that
will be affected by treatment, particularly radiotherapy should have a pre-treatment assessment. This should be done as early as possible to maximise the time available for dental management. However, this can be challenging owing to the complexities of cancer diagnosis, treatment planning and multidisciplinary management. At the Belfast Dental Hospital, a number of patients were referred post- radiotherapy with complications after not having received a pre-treatment assessment. The referrals for pre- treatment dental assessment were also late in patients’ multidisciplinary journey, limiting the time period
for dental input. The purpose of this audit was to examine the time period between dental assessment and commencement of radiotherapy and whether this was an adequate time frame for dental management. This audit will also examine the dental diseases present and the treatments required pre-radiotherapy. Methods: Data for this audit was collected over 4 months in 2012
by analysing the dental charts and referrals of new patients who were referred to and attended the dental head and neck oncology clinic. A standardised referral pro-forma was introduced from September 2013 to improve the referral process.
A re-audit was conducted over 4 months in 2014. Data was collected similarly as previous. The time period between dental assessment and commencement of radiotherapy was examined. The presence of dental disease and subsequent treatments required were also noted.
Results: 63 new patients were examined in the dental head and neck oncology clinic over 4 months in 2012. 48 (76.2%) were examined pre-radiotherapy. The average length of time between dental assessment and radiotherapy commencement was 11 days. A new standardised referral pro-forma was introduced in 2013. In the re-audit, 65 new patients were seen over 4 months in 2014.
60 (92.3%) patients were examined pre-radiotherapy. The average length of time between dental assessment and radiotherapy commencement was 18 days.
Conclusion: Given the high prevalence of pre-existing dental disease amongst head and neck cancer patients, prompt dental assessment and treatment is vital. Efforts aimed at improving the care pathway are on-going through the implementation of a mandatory referral pro-forma and a dedicated assessment clinic.

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In many applications, and especially those where batch processes are involved, a target scalar output of interest is often dependent on one or more time series of data. With the exponential growth in data logging in modern industries such time series are increasingly available for statistical modeling in soft sensing applications. In order to exploit time series data for predictive modelling, it is necessary to summarise the information they contain as a set of features to use as model regressors. Typically this is done in an unsupervised fashion using simple techniques such as computing statistical moments, principal components or wavelet decompositions, often leading to significant information loss and hence suboptimal predictive models. In this paper, a functional learning paradigm is exploited in a supervised fashion to derive continuous, smooth estimates of time series data (yielding aggregated local information), while simultaneously estimating a continuous shape function yielding optimal predictions. The proposed Supervised Aggregative Feature Extraction (SAFE) methodology can be extended to support nonlinear predictive models by embedding the functional learning framework in a Reproducing Kernel Hilbert Spaces setting. SAFE has a number of attractive features including closed form solution and the ability to explicitly incorporate first and second order derivative information. Using simulation studies and a practical semiconductor manufacturing case study we highlight the strengths of the new methodology with respect to standard unsupervised feature extraction approaches.

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Objectives: To evaluate the placement of composite materials by new graduates using three alternative placement techniques.Methods: A cohort of 34 recently qualified graduates were asked to restore class II interproximal cavities in plastic teeth using three different techniques.

(i) A conventional incremental filling technique (Herculite XRV) using increments no larger than 2-mm with an initial layer on the cervical floor of the box of 1-mm.
(ii) Flowable bulk fill technique (Dentsply SDR) bulk fill placement in a 3-mm layer followed by an incremental fill of a microhybrid resin
(iii) Bulk fill (Kerr Sonicfill) which involved restorations placed in a 5-mm layer.

The operators were instructed in each technique, didactically and with a hands-on demonstration, prior to restoration placement.
All restorations were cured according to manufacturer’s recommendations. Each participant restored 3 teeth, 1 tooth per treatment technique.
The restorations were evaluated using modified USPHS criteria to assess both the marginal adaptation and the surface texture of the restorations. Blind evaluations were carried out independently by two examiners with the aid of magnification (loupes X2.5). Examiners were standardized prior to evaluation.
Results: Gaps between the tooth margins and the restoration or between the layers of the restoration were found in 13 of Group (i), 3 of Group (ii), and 4 of Group (iii)
Statistical analysis revealed a significant difference between the incrementally filled group (i) and the flowable bulk-fill group (ii) (p=0.0043) and between the incrementally filled (i) and the bulk fill groups (iii) (p=0.012) and no statistical difference (p=0.69) between the bulk filled groups Conclusions: Bulk fill techniques may result in a more satisfactory seal of the cavity margins when restoring with composite.

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Factor XI is a serine protease that participates in the intrinsic pathway of blood coagulation. Patients deficient in factor XI exhibit varying degrees of post operative bleeding following invasive surgical procedures such as dental extractions. Objectives: The aim of the study was to identify the specific mutations in a patient from a family with known factor XI deficiency. Methods: Samples were obtained from the patient, his mother and his father and subjected to DNA sequencing. Each protein coding exon 2-15 of the factor XI gene was amplified by polymerase chain reaction (PCR) followed by bidirectional sequencing utilizing di-deoxy chain termination chemistry. Results: The patient had a factor XI level of 20% of normal. Initial sequencing of factor XI from the patient identified a point mutation (646G>A) and a putative splice site mutation (1567+4A>T) in intron 13. These are novel previously unreported mutations. DNA sequence analysis of the mother revealed the 1567+4A>T mutation and the father exhibited the 646G>A mutation. As a consequence the treatment proceeded without serious bleeding complication and required administration only of transexamic acid though factor XI was available as haemostatic cover. Conclusion: The two mutations identified in this family are novel; further laboratory investigation of the functional consequences of those mutations is currently underway. Although factor XI deficiency is rare in the Northern Irish population this study highlights the techniques available to sequence and analyse this and similar haematological disorders.

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In the catalytic hydrogenation of benzene to cyclohexane, the separation of unreacted benzene from the product stream is inevitable and essential for an economically viable process. In order to evaluate the separation efficiency of ionic liquids (ILs) as a solvent in this extraction processes, the ternary (liquid + liquid) equilibrium of 1-alkyl-3-methylimidazolium hexafluorophosphate, [Cnmim][PF6] (n = 4, 5, 6), with benzene and cyclohexane was studied at T = 298.15 K and atmospheric pressure. The reliability of the experimentally determined tie-line data was confirmed by applying the Othmer–Tobias equation. The solute distribution coefficient and solvent selectivity for the systems studied were calculated and compared with literature data for other ILs and sulfolane. It turns out that the benzene distribution coefficient increases and solvent selectivity decreases as the length of the cation alkyl chain grows, and the ionic liquids [Cnmim][PF6] proved to be promising solvents for benzene–cyclohexane extractive separation. Finally, an NRTL model was applied to correlate and fit the experimental LLE data for the ternary systems studied.

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Separation of benzene and cyclohexane is one of the most important and difficult processes in the petrochemical industry, especially for low benzene concentration. In this work, three ionic liquids (ILs), [Bmim][BF 4], [Bpy][BF 4], and [Bmim][SCN], were investigated as the solvent in the extraction of benzene from cyclohexane. The corresponding ternary liquid-liquid equilibria (LLE) were experimentally determined at T = 298.15 K and atmospheric pressure. The LLE data were correlated with the nonrandom two-liquid model, and the parameters were fitted. The separation capabilities of the ILs were evaluated in terms of the benzene distribution coefficient and solvent selectivity. The effect of the IL structure on the separation was explained based on a well-founded physical model, COSMO-RS. Finally, the extraction processes were defined, and the operation parameters were analyzed. It shows that the ILs studied are suitable solvents for the extractive separation of benzene and cyclohexane, and their separation efficiency can be generally ranked as [Bmim][BF 4] > [Bpy][BF 4] > [Bmim][SCN]. The extraction process for a feed with 15 mol % benzene was optimized. High product purity (cyclohexane 0.997) and high recovery efficiency (cyclohexane 96.9% and benzene 98.1%) can be reached. © 2012 American Chemical Society.

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Objective: To evaluate the handling, by a group of practice-based researchers, of a recently introduced bulk fill resin-based composite restorative material, Filtek Bulk Fill Restorative (3M ESPE).

Methods: The twelve selected evaluators were sent explanatory letters, a pack of the material under investigation to use for 8 weeks, and a questionnaire.

Results: The evaluators rated the ease of use of the bulk fill restorative the same as the previously used posterior composite material. The provision of one shade only for evaluation may have compromised the score for aesthetic quality. No post-operative sensitivity was reported.

Conclusions: The bulk fill material was well received as indicated by the high number of evaluators who would both purchase the material and recommend it to colleagues.

Clinical relevance: A recently introduced bulk fill restorative material achieved a rating for handling which was similar to the evaluators’ previously used resin composite, although there were some concerns regarding the translucency of the material.

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Learning or writing regular expressions to identify instances of a specific
concept within text documents with a high precision and recall is challenging.
It is relatively easy to improve the precision of an initial regular expression
by identifying false positives covered and tweaking the expression to avoid the
false positives. However, modifying the expression to improve recall is difficult
since false negatives can only be identified by manually analyzing all documents,
in the absence of any tools to identify the missing instances. We focus on partially
automating the discovery of missing instances by soliciting minimal user
feedback. We present a technique to identify good generalizations of a regular
expression that have improved recall while retaining high precision. We empirically
demonstrate the effectiveness of the proposed technique as compared to
existing methods and show results for a variety of tasks such as identification of
dates, phone numbers, product names, and course numbers on real world datasets

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A method is described for the rapid extraction of pectic substances from alcohol insoluble solids (AIS) from material of plant origin, especially fruit. Samples of AIS can be prepared for galacturonic acid assay within 60 min using extraction with 0·5m HCl in a Fibertec-1 system (Tecator) for 30 min. The extraction conditions are carefully standardised and operator error is reduced by the elimination of transfer steps, particularly during filtration. The results obtained for plant-derived alcohol insoluble solids containing from 10% to 33% pectic substances were in close agreement with those obtained by enzymic hydrolysis using a commercially available enzyme preparation (Ultrazyme). The method will have application in the rapid, routine estimation of pectic substances in plant materials. © 1987.

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Neuropeptides such as neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) have been shown by our research group to be present in human dental pulp tissue. Neuropeptides cannot cross cell membranes and therefore to exert their biological effects they must bind to selected receptors on the surface of target cell membranes. However, the expression of receptor proteins for NPY and/or VIP have yet to be reported in human pulp tissue. The presence of neuropeptide receptors can be conveniently determined by Western blotting using specific anti-receptor antibodies. Objectives: The aim of this work was to identify the presence of the NPY Y1 receptor and the VIP receptor VPAC1 in human dental pulp tissue from both intact and carious teeth using Western blotting. Methods: Pulp tissue was collected from both intact and carious teeth and membrane preparations from these tissues were then subject to sodium dodecyl sulphate gel electrophoresis (SDS-PAGE), transferred to nitrocellulose and probed with specific antibodies to either the NPY Y1 receptor or the VPAC1 receptor. Results: Individual Western blotting experiments revealed the presence of immunoreactive bands corresponding to the known molecular weights of the NPY Y1 and VPAC1 receptor proteins in both intact and carious pulp samples. Conclusions: Demonstration of the presence of NPY Y1 and VPAC1 receptor protein expression in pulpal tissue from intact and carious teeth provides further support for the roles of these neuropeptides in pulpal health and disease.

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Neuropeptide Y is a 36 amino acid peptide that belongs to the pancreatic polypeptide family. It co-localises with adrenaline in sympathetic nerves and is released upon sympathetic activation resulting in vasoconstriction. In addition to its vascular effects NPY is also thought to have a role in pain modulation, angiogenesis and immunomodulation. Objectives: The aim of this study was to quantify the levels of NPY in human dental pulp tissue from intact and grossly carious teeth and to relate these results to pain experience. Methods: A total of 48 permanent teeth [mean age 32.1(+/- 11.2 years)] were included in the study, of these 22 were intact and 26 were grossly carious. In the grossly carious group, 17 teeth were reported painful prior to extraction and the remainder were reported non-painful. NPY was measured using a sensitive and specific radioimmunoassay which has been previously described. Pain was scored as either present or absent in all the teeth studied. Results: Of particular interest in this study was the finding that NPY levels were significantly higher in dental pulp tissue from non-painful grossly carious teeth (p= 0.006) compared with painful grossly carious teeth. Conclusions: The increased levels of NPY reported in non-painful grossly carious teeth may suggest a role for NPY in pain modulation in human dental pulp.