212 research outputs found

    Apical extrusion of debris using reciprocating files and rotary instrumentation systems

    Get PDF
    Background: To compare the preparation time and amount of apically extruded debris after the  preparation of root canals in extracted human teeth using the reciprocating files and rotary nickel.titanium systems.Procedure: Sixty extracted human mandibular premolars were used. The root canals were instrumented using reciprocating (WaveOne, Reciproc, SafeSider) or rotary motion (Typhoon, ProTaper Universal,  Mtwo), and the debris produced was collected in glass vials. The remaining debris was assessed using a microbalance and statistically analyzed using the one.way ANOVA and Duncan multiple range tests at a significance level of P < 0.05. The time required to prepare the canals with different instruments was also recorded.Results: The Reciproc group produced significantly less debris when compared to the Typhoon group (P < 0.05), and instrumentation with the single.file systems was significantly faster than in the multi.file systems (P < 0.05). The WaveOne group extruded significantly more debris per unit of time than the other groups, with the exception of the Typhoon group (P < 0.05).Conclusion: According to our study, all systems caused apical debris extrusion. However, the Reciproc group was associated with less debris extrusion when compared to the other groups.Key words: Apical extrusion, endodontics, single file system

    Does Deep Tectonic Tremor Occur in the Central‐Eastern Mediterranean Basin?

    Get PDF
    Tectonic tremor has been observed at the roots of many fault systems around the Pacific rim, including convergent and transform plate boundaries. The extent to which deep tremor signals are prevalent along fault systems elsewhere, including the Mediterranean basin, has not yet been documented in detail. A body of evidence suggests that tremor triggered during the surface waves of teleseismic events may commonly occur where ambient tremor during episodic tremor and slip episodes occur, suggesting triggered tremor provides a useful tool to identify regions with ambient tremor. We perform a systematic search of triggered tremor associated with large teleseismic events between 2010 and 2020 at four major fault systems within the central-eastern Mediterranean basin, namely the Hellenic and Calabrian subduction zones, and the North Anatolian and Kefalonia transform faults. In addition, we search for ambient tremor during a slow slip event in the eastern Sea of Marmara along a secondary branch of the North Anatolian Fault, and two slow slip events beneath western Peloponnese (Hellenic Subduction Zone). We find no unambiguous evidence for deep triggered tremor, nor ambient tremor. The absence of triggered tremor at the Hellenic and Calabrian subduction zones supports an interpretation of less favorable conditions for tremorgenesis in the presence of old and cold slabs. The absence of tremor along the transform faults may be due to an absence of the conditions commonly promoting tremorgenesis in such settings, including high-fluid pressures and low-differential stresses between the down-dip limit of the seismogenic layer and the continental Moho

    Continuability and boundedness of solutions for a kind of nonlinear delay integro-differential equations of third order

    No full text
    This paper considers a nonlinear integro-differential equation of third order with delay. We establish sufficient conditions which guarantee the globally existence and boundedness of the solutions of the equation considered. We benefit from the Lyapunov’s second method to prove the main result. An example is also given to illustrate the applicability of our result. The result of this paper is new and improves previously known results.Вивчається нелiнiйне iнтегро-диференцiальне рiвняння третього порядку з запiзненням. Наведено достатнi умови глобального iснування та обмеженостi розв’язкiв розглянутих рiвнянь. Для доведення основного результату використовується другий метод Ляпунова. Також наведено приклад для iлюстрацiї отриманого результату. Отриманий результат є новим та покращує отриманi ранiше результати
    corecore