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Guided eruption of palatally impacted canines through combined use of 3-dimensional computerized tomography scans and the easy cuspid device.
No full textLocal gravitational instability of two-component thick discs in three dimensions
No full textAims. The local gravitational instability of rotating discs is believed to be an important mechanism in different astrophysical processes, including the formation of gas and stellar clumps in galaxies. We aim to study the local gravitational instability of two-component thick discs in three dimensions. Methods. We use as a starting point a recently proposed analytic three-dimensional (3D) instability criterion for discs with non-negligible thickness that takes the form Q3D < 1, where Q3D is a 3D version of the classical 2D Toomre Q parameter for razor-thin discs. Here, we extend the 3D stability analysis to two-component discs, considering first the influence on Q3D of a second unresponsive component, and then the case in which both components are responsive. We present the application to two-component discs with isothermal vertical distributions, which can represent, for instance, galactic discs with both stellar and gaseous components. Finally, we relax the assumption of vertical isothermal distribution, by studying one-component self-gravitating discs with polytropic vertical distributions for a range of values of the polytropic index corresponding to convectively stable configurations. Results. We find that Q3D < 1, where Q3D can be computed from observationally inferred quantities, is a robust indicator of local gravitational instability, depending only weakly on the presence of a second component and on the vertical gradient of temperature or velocity dispersion. We derive a sufficient condition for local gravitational instability in the midplane of two-component discs, which can be employed when both components have Q3D > 1
Paediatric laser dentistry. Part 3: Dental trauma
Full text linkDental traumas are frequent and sometimes complex events, and at times real emergencies. There are no well coded guidelines for laser applications in these clinical events. Laser-assisted therapy can offer new treatment possibilities, simplify dental procedures, reduce postoperative sensitivity and the need for post-operative medications because of the laser-induced biostimulating and anti-inflammatory effects
Comparazione clinico-strumentale di differenti apparecchiature ortodontiche nella terapia dell’apnea notturna ostruttiva
No full textA long-term retrospective clinical study on MTA pulpotomies in immature permanent incisors with complicated crown fractures
No full textThe study was undertaken to evaluate mineral trioxide aggregate (MTA) clinically and radiographically as a pulpotomy agent in immature permanent teeth whose pulps were exposed by a complicated crown fracture.Thirty incisors with exposed pulps in twenty-nine patients were examined for this retrospective study. According to exclusion criteria, only twenty-seven teeth were selected. Each tooth was treated with partial pulpotomy and the wounded pulp was covered with mineral trioxide aggregate. The children were recalled for clinical and radiographic evaluation at 3 months, 6 months, at approximately 12 months and 36 months.Out of 27 cases, 22 were categorized as 'healed' and 1 as 'healing'. The remaining 4 ones highlighted persistent disease and needed further endodontic treatment.MTA partial pulpotomy is an effective treatment in maintaining pulpal vitality and allowing physiological root development (apexogenesis)
Comparazione clinico-strumentale di differenti apparecchiature ortodontiche nella terapia dell’apnea notturna ostruttiva
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