An implant periapical lesion associated with presence of residual root fragments: Report of case treated with apicoectomy

Indexación: Scopus.Chemicals and CAS Registry Numbers: azithromycin, 83905-01-5, 117772-70-0, 121470-24-4; chlorhexidine, 3697-42-5, 55-56-1; erythromycin, 114-07-8, 70536-18-4The present study reports a case of a periapical lesion in an implant placed in an alveolar ridge which presented a residual root fragment of a deciduous tooth. Patient attended a dental clinic because she wanted to replace the missing tooth with an implant. She reported having lost the temporary tooth for one year. The initial Cone-beam Computerised Tomography image showed an edentulous area in the #13 zone, and the presence of a fragment of the deciduous tooth. The small root fragment was removed and an implant 4.0 × 13 mm amplified was installed. Patient presented acute pain and inflammation at the implant site 20 d after the surgery when the implant was originally installed; the first periapical surgery was carried out. Four months after the first periapical surgery, in periapical x-ray a radiolucent lesion was observed surrounding the apical region of the implant with a dry sound under percussion. The second periapical surgery was carried out. Five months after the second periapical surgery, the presence of a fistula was observed clinically, while in X-ray a radiolucent lesion was observed in the apex of the implant. Implant-plasty was carried out, removing approximately 5 mm of the apical portion of the implant. This treatment was successful after 27 months' monitoring. © 2018, Scientific Publishers of India. All rights reserved.https://www.alliedacademies.org/articles/an-implant-periapical-lesion-associated-with-presence-of-residual-root-fragments-report-of-case-treated-with-apicoectomy-10489.htm

Uncovering the Beast: Discovery of Embedded Massive Stellar Clusters in W49A

We present subarcsecond J, H, and Ks images (FWHM ~ 0.5") of an unbiased 5'x 5' (16pc x 16pc) survey of the densest region of the W49 giant molecular cloud. The observations reveal 4 massive stellar clusters (with stars as massive as \~120 Msun), the larger (Cluster 1) about 3 pc East of the well known Welch ring of ultra-compact Hii regions. Cluster 1 is a) extincted by at least Av > 20 mag of foreground (unrelated and local) extinction, b) has more than 30 mag of internal inhomogeneous visual extinction implying that it is still deeply buried in its parental molecular cloud, and c) is powering a 6 pc diameter giant Hii region seen both at the NIR and radio continuum. We also identify the exciting sources of several UCHii regions. The census of massive stars in W49A agrees or is slightly overabundant when compared with the number of Lyman continuum photons derived from radio observations. We argue that although the formation of the Welch ring could have been triggered by Cluster 1, the entire W49A starburst region seems to have been multi-seeded instead of resulting from a coherent trigger.Comment: ApJ Letters accepted. All figures provided as nice resolution jpeg/gif files. Get full-res version at http://www.eso.org/~jalves/W49A.pd

Bandwidth aspects in second generation current conveyors

This paper discusses bandwidth problems associated with second-generation current conveyors (CCII). In particular, our work is centered in high-capacitance applications, and has been oriented for wireless optical links and applied physics. We discuss techniques for improving bandwidth in these CCIIs, and develop a new CCII structure with larger bandwidth than traditional circuits. These circuits are then compared in terms of their noise and dynamic range characteristics. A test circuit was developed to verify these different bandwidth behaviors

Evaluating the impacts of an urban catchment on water and sediment quality of a receiving river

The EU Water Framework Directive requires all water bodies to achieve good ecological and chemical status by 2027. To achieve this a range of measures to improve the quality of water, particularly in urban areas, are required. It is within this context that this thesis uses a combination of field, laboratory and desk-based studies to identify contaminant loadings and their distributions within water bodies located in the Lower Lee catchment (London, United Kingdom). Specifically, water and sediment samples were collected at 11 sites on the River Lee, its’ Navigation Channel and main tributaries, over a period of two years. Samples were analysed for a range of metals (cadmium, copper, lead, mercury, nickel, tin and zinc) and 11 polyaromatic hydrocarbons (PAHs) including anthracene, fluoranthene, benzo(b)fluoranthene and benzo(a)pyrene. Laboratory batch test experiments which focused on evaluating the release of metals from field sediments were undertaken to better understand the relationship between sediment and the overlying water column. Substance flow analysis (SFA) was then applied to predict mass loads of selected pollutants entering the receiving waters within 1 km of sampling sites to evaluate the potential use of the approach as a screening tool to identify pollutant hotspots in an urban river catchment. Field sampling data and substance flow analysis outputs were compared to evaluate the use of substance flow analysis as a desk-based approach to predict sediment pollutant hotspots in the field. Use of the approach as a tool to support catchment managers identify locations for interventions to improve water and sediment quality, as well inform the development of policies targeting environmental enhancement, are discussed. The results show that mean cadmium (2.33 ± 2.79 μg/g), copper (141.07 ± 111.00 μg/g), mercury (0.53 ± 0.45 μg/g), lead (175.70 ± 82.96 μg/g) and zinc (499.92 ± 264.66 μg/g) concentrations in the sediment exceed selected Dutch (Esdat, 2000) and Canadian (CCME, 2001) sediment guidelines. Comparison of mean polyaromatic hydrocarbon concentrations against relevant Canadian and Dutch sediment guidelines also indicates exceedances. With regard to aqueous samples, results reported here refer to total metal concentrations whereas the United Kingdom Technical Advisory Group and European Union Environmental Quality Standard both refer to dissolved and/or bioavailable concentrations. Thus, the exact implications of comparison of results to these standards are unclear as the fraction of each metal in the dissolved phase was not determined. Batch test results indicated that the amount of metal released into the sediment varied between metals and sites with the level of variation generally within an order of magnitude, ranging from a minimum of 0.12 % (tin, site A) to a maximum of 6.12 % (cadmium, site E). Through the use of reported emission factors, the substance flow analysis results predicted that a total of 19,304 kg/year (sum of six metals) and 781 kg/year (sum of five polyaromatic hydrocarbons) were discharged from the identified activities into surface waters within 1 km of each sampling site , with Deephams Sewage Treatment Works associated with a total of 6,715 kg/year for metals and a total of 12 kg/year for PAHs, corresponding to 33.5% of the total discharges for all selected pollutants (metals and PAHs) by mass. When evaluating trends in substance flow analysis predictions in relation to sediment field data, a very strong correlation (r ≥ 0.94 and p ≤ 0.05), was observed for the tributaries for cadmium, copper, mercury, lead and zinc, suggesting that substance flow analysis is a suitable tool to support catchment managers in identifying sediment metal hotspots in relatively smaller water bodies. However, the relationships between field and substance flow analysis data sets for metals at other sites and for PAHs at all sites (with the exception of anthracene) were not statistically significant. This indicates that all PAH predicted loads do not reflect those determined in river sediment. A range of substance flow analysis model limitations were identified, including the inability of the current approach to include emissions from combined sewer overflows and aerial deposition as well as account for in-sediment processes such as remobilisation, transport and degradation and further research in these areas is recommended