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

On the effect of time delays in negative feedback amplifiers

Time delays are intrinsic to all existing devices and circuits. For the majority of applications, time delays are so small that their effects can be disregarded. However, when considering feedback amplifiers, depending on open-loop poles and loop gain, the effect of a small time delay inside the feedback path may turn to be of considerable importance. This paper analyzes the frequency response effects associated with time delays in feedback amplifiers, exploiting these effects to achieve bandwidth enhancements. An illustration of this effect is presented using a TL082 in series-shunt configuration, attaining 100% bandwidth extension, when associated with a 36m length RG58 coaxial cable as delay element. © 2005 IEEE

Optimized cross-slot flow geometry for microfluidic extension rheometry

A precision-machined cross-slot flow geometry with a shape that has been optimized by numerical simulation of the fluid kinematics is fabricated and used to measure the extensional viscosity of a dilute polymer solution. Full-field birefringence microscopy is used to monitor the evolution and growth of macromolecular anisotropy along the stagnation point streamline, and we observe the formation of a strong and uniform birefringent strand when the dimensionless flow strength exceeds a critical Weissenberg number Wicrit 0:5. Birefringence and bulk pressure drop measurements provide self consistent estimates of the planar extensional viscosity of the fluid over a wide range of deformation rates (26 s1 "_ 435 s1) and are also in close agreement with numerical simulations performed by using a finitely extensible nonlinear elastic dumbbell model