The Disinfecting Efficacy of Root Canals with Laser Photodynamic Therapy

Introduction: Infecting microorganisms of the root canals are difficult to eliminate during endodontic treatment. In this study the effect of root canal disinfection with photodynamic therapy (PDT) at different time intervals in comparison to 2.5% sodium hypochlorite (NaOCl) irrigation and passive ultrasonic irrigation (PUI) in extracted teeth colonized with Enterococcus faecalis and Candida albicans was tested to assess which treatment reaches the best disinfection rate.Methods: One hundred and fifty-six extracted single-rooted teeth were collected, sterilized, and incubated with Enterococcus faecalis (ATCC 29212) and Candida albicans (ATCC 60193). The two groups were further divided into 6 groups depending on the treatment mode; HELBO®Endo Blue photosensitizer dye application followed by HELBO laser irradiation, with the output power 100 mW and emission of 660 nm, for a 1, 3 and 5 minutes, irrigation with 2.5% NaOCl, 10 second PUI with 2.5% NaOCl and control group. Flow cytometry and scanning electron microscopic (SEM) analysis were used to determine the effectiveness of the different disinfecting methods.Results: The different disinfecting methods had a significantly different effect on the percent of dead cells (p<0.001). A statistical significance of dead cells between organisms (p<0.001) was observed. Interaction between the disinfecting method and both of organisms had shown the statistical significance (p=0.045). Percent of dead cells in treatment groups were significantly higher compared to control group for both organisms (p<0.001).Conclusions: PUI still remains the most effective method for disinfection of infected root canalsin endodontics compared to hand instrumentation for both microorganisms. SEM analysis only confirmed the results. Other results ex vivo suggested that prolonging the time from 1 to 5 minutes of PDT increased the number of killed microorganisms significantly, therefore longer times of photodynamic therapy were recommended. Irrigation with 2.5% NaOCl showed similar results to 5 min irradiation

Systematic Beam Parameter Studies at the Injector Section of FLUTE

FLUTE (Ferninfrarot Linac- und Test-Experiment) is a compact linac-based test facility for accelerator R&D and source of intense THz radiation for photon science. In preparation for the next experiments, the electron beam of the injector section of FLUTE has been characterized. In systematic studies the electron beam parameters, e.g., beam energy and emittance, are measured with several diagnostic systems. This knowledge allows the establishment of different operation settings and the optimization of electron beam parameters for future experiments

ACS – THE ADVANCED CONTROL SYSTEM

The ACS is a CORBA-based control system framework with all features expected from a modern control system. It has been recently installed at the ANKA light source in Karlsruhe, Germany and is being used to develop the ALMA control system. ALMA is a joint project between astronomical organisations in Europe, USA and Japan and will consist of 64 12-meter sub-millimetre radio telescopes. ACS provides a powerful XML-based configuration database, synchronous and asynchronous communication, configurable monitors and alarms that automatically reconnect after a server crash, run-time name/location resolution, archiving, error system and logging system. Furthermore, ACS has built-in management, which allows centralized control over processes with commands such as start/stop/reload, send message, disconnect client, etc. and is fine-grained to the level of single devices. ACS comes with all necessary generic GUI applications and tools for management, display of logs and alarms and a generic object explorer, which discovers all CORBA objects, their attributes and commands at run-time and allows the user to invoke any command. A Visual configuration database editor is under development. An XML/XSLT generator creates an Abeans plug for each controlled object, giving access to all Abeans applications such as snapshot, table, GUI panels, and allowing one to use the CosyBeans GUI components for creating Java applications. For those that write their own control system, ACS allows to define own types of controlled data and own models of communication, yet use powerful support libraries as long as one adheres to some rules in the form of programming patterns. ACS users several standard CORBA services such as notification service, naming service, interface repository and implementation repository. ACS hides all details of the underlying mechanisms, which use many complex features of CORBA, queuing, asynchronous communication, thread pooling, life-cycle management, etc. Written in C++ and using the free ORB TAO, which is based on the operating system abstraction platfor