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A letter to the editor in response to the article "Major psychological complications and decreased health-related quality of life among survivors of Stevens-Johnson syndrome and toxic epidermal necrolysis," that was published in a previous issue of the journal is presented.

Dental displacement, an obligatory state for a good result of an orthodontic treatment, is obtained by bone resorption and apposition, resulting from an inflammatory process localized at this level. Lymphocytes produce a large number of peptides with regulatory functions upon the organism in autocrine, paracrine or at high distance (endocrine) ways. These peptides were described as cytokines. Among these, interleukin 1β and interleukin 8 are the main proinflammatory cytokines, and they can be use as inflammation markers. In these conditions, the objective of this paper is the assessment of the IL β and IL-8 levels in the gingival crevicular fluid of the orthodontic tractioned teeth compared to the teeth upon which no orthodontic force is applied, before as well as after the device application. The patients taken into this study were 12 girls and 6 boys, between 7 and 12 years, average age of 9.3 years, who exhibited an orthodontic tooth movement of a single tooth (experimental tooth), the homonym tooth from the antagonistic arcade being considered as control. The gingival fluid was sampled before the beginning of the treatment, and after 1 hour, 24 hours and 7 days from the device application. The levels of IL-1β and IL-8 in the gingival crevicular fluid was assessed by ELISA technique. The level of the two pro-inflammatory interleukins in the gingival fluid of the tractioned teeth was significantly higher (p<0,01) at 24 hours from the device application compared with the control teeth; at 7 days from the beginning of the treatment, only the IL 8 level in the experimental teeth being significantly higher compared with the control teeth. These results demonstrate that the levels of IL-1β and IL-8 in the gingival fluid increase with the dental movement taking place, due to a localized inflammatory process, as a response to mechanical stress. [ABSTRACT FROM AUTHOR]

The use of orthodontic appliances in the treatment of the various dento-maxillar anomalies most frequently presume the application of high intensity forces, non-physiological, which always will produce an inflammatory response localised around the tooth or the teeth subjected to displacement. The presence of an inflammatory process at this level will produce an increased synthesis of free radicals, secondary followed by the oxidative stress. In order to asses the level of the oxidative stress, a series of its markers are used, including the reactive species of oxygen and nitrogen, and the oxidation products in particular, such as lipid peroxides and oxidized proteins respectively. Thus, the objective of the present study is to determine and compare the levels of some oxidative stress markers (malondialdehyde, ceruloplasmine, hydrogen donors) in saliva of patients with orthodontic appliances, before and after the initiation of the treatment. The patients included in this study were 7 girls and 4 boys, with the average age of 9.9 years, in which orthodontic biomechanical appliances were applied, in the purpose of treatment of some dento-maxillar anomalies. Saliva has been collected before the initiation of the orthodontic treatment, at 1 hour, at 24 hours, and at 7 days from from the orthodontic appliance application. The variations in the concentrations of the saliva markers of the oxidative stress reached a maximum at 24 hours from the debut of the treatment for ceruloplasmine and malondialdehyde, and at one hour for the hydrogen donors respectively, while at 7 days from the device application the concentrations were close to the initial values. The health condition at the level of the oral cavity in the patients taken into study did not change during the research. These results demonstrate that the utilization of an orthodontic appliance changes the levels of the saliva markers of oxidative stress, but these variations, even statistically significant, do not determine the appearance of certain pathological processes at the level of the oral cavity. [ABSTRACT FROM AUTHOR]

Abstract: Within the frame of this work, low temperature Ti–Si–C films were deposited on high-speed steel and stainless steel substrates by combined dc/rf magnetron co-sputtering. Composition analysis revealed the existence of two distinct regions: (i) a silicon doped sub-stoichiometric titanium carbide zone and (ii) a titanium rich zone. Structural analysis confirmed the different nature of the prepared films within each of the two zones. The residual stress states (σ r) were relatively low, and the hardness values ranged between 11 and 27GPa, with a dependence on the composition as well as on the structural features. The tribological results showed quite similar trends, with both friction coefficients and wear revealing a straight correlation with the composition, and consequently, the different structural arrangements. In general terms, the obtained results showed that the friction coefficient of the samples tended to decrease with increasing C C/C Si atomic ratio, indicating an improvement in tribological behaviour for the samples with the highest carbon contents. In terms of wear resistance, the films with a stoichiometry very close to TiC, Si doped sub-stoichiometric titanium carbide films, presented the best behaviours, revealing that a compromise between the best friction and wear, must be made in order to select the optimum coating. [Copyright &y& Elsevier]

Abstract: The assessment of a radioactive waste drum is generally difficult due to its high volume, the complex and usually unknown distribution of the waste in the drum and its high self-attenuation. To solve these problems, a complex calibration of the system is required. An experimental calibration using the shell-sources method was performed in order to determine the efficiency appropriate for a uniformly distributed source. For this purpose, a calibration drum filled with Portland cement and provided with seven tubes, placed at different distances from its center was used. Monte Carlo calculations using the GESPECOR software were carried out in order to complement experimental calibration. Thus, efficiency values for different geometries were obtained and compared with the experimental values. [Copyright &y& Elsevier]