Title: 1430 - The 445nm Laser in Endodontics – A Pilot in vivo Study


Johannes-Simon Wenzler (Presenter)
University of Marburg

Sebastian Schramm, University of Marburg
Julia Winter, University of Marburg
Wolfgang Falk, Center for Dental Microbiology
Roland Frankenberger, University of Marburg
Andreas Braun, University of Marburg


Objectives: The success of root canal treatment depends on a sufficient elimination of pathogenic germs. The aim of the present pilot study was to evaluate a novel 445 nm semiconductor laser for its germ-reducing effect during chemomechanical root canal treatment.

Methods: As part of the regular endodontic treatment regimen, microbiological specimens of 15 patients were collected with paper points after endodontic emergency treatment in the following sequence: (I) removal of the temporary filling material, (II) chemomechanical treatment (hand/machine-driven instrumentation (ProTaper Gold, Dentsply DeTrey, Konstanz, Germany), rinsing with sodium hypochlorite (3%), (III) according to one of three adjuvant group-specific protocols. As adjuvant protocols (n=5 each) following groups were defined (ethics committee approval: (a) sodium hypochlorite rinsing (3%), (b) laser irradiation, (c) combination of sodium hypochlorite rinsing and laser irradiation. The diode laser (SiroLaser Blue, Dentsply Sirona, Bensheim, Germany) in groups (b) and (c) was used with the settings 0.6W in continuous wave mode (cw) for 4x10s. The samples were collected after flooding the root canal with saline solution, transferred into transport vessels and analyzed microbiologically by quantitative real-time PCR: Total bacterial load (TBL) was assessed as main parameter.Statistical analysis was performed with non-parametric tests (Wilcoxon, Mann-Whitney).

Results: A statistically significant bacterial reduction could be observed In all three groups under study (p<0.05): laser therapy alone 72.4% (min: 39.4, max: 99.9), sodium hypochlorite rinsing alone 92.0% (min: 66.6; max: 99.4). Both groups showed less reduction than the combination of sodium hypochlorite rinsing and 445 nm laser irradiation with 95.8% (min: 85.3, max: 97.8) (p>0.05).

The present pilot study showed a tendencially better bacterial reduction with combined 445nm laser irradiation and sodium hypochlorite rinsing. Performing a power-analysis, a statistically significant difference between the study groups can be expected for a number of at least 18 patients per group.

This abstract is based on research that was funded entirely or partially by an outside source:
Dentsply Sirona

Disclosure Statement:
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: None

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