Dental and Medical Problems

Dent Med Probl
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Dental and Medical Problems

2017, vol. 54, nr 4, October-December, p. 333–338

doi: 10.17219/dmp/77898

Publication type: original article

Language: English

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Creative Commons BY-NC-ND 3.0 Open Access

Effects of 980 nm diode laser application protocols on the reduction of Enterococcus faecalis intracanal biofilm: An in vitro study

Efekty zastosowania promieniowania laserowego o długości fali 980 nm na redukcję wewnątrzkanałowego biofilmu bakteryjnego Enterococcus faecalis – badania in vitro

Ewa Joanna Prażmo1,A,B,C,D,E,F, Alicja Renata Godlewska2,B,D, Monika Sałkiewicz2,B, Agnieszka Beata Mielczarek1,D,E,F

1 Department of Conservative Dentistry, Medical University of Warsaw, Warsaw, Poland

2 Department of Bacterial Genetics, Faculty of Biology, University of Warsaw, Warsaw, Poland


Background. Enterococcus faecalis is associated with a great number of refractory endodontic infections. There is a need to investigate antibacterial properties of laser radiation and create a new alternative technique for root canal disinfection.
Objectives. The purpose of the study was to investigate the effectiveness of a single and repeated highpower diode laser irradiation protocol on the elimination of a 1-week-old Enterococcus faecalis intracanal biofilm.
Material and Methods. A total of 46 single-rooted human teeth were subjected to the in vitro observation. They were chemomechanically prepared, sterilized, infected with a clinically isolated strain of Enterococcus faecalis and subjected to 1-week incubation under microaerobic conditions. The experimental procedures included: a single cycle of 980 nm laser diode irradiation, second application of the same laser protocol, 5.25% NaOCl irrigation, and 2 control groups. Quantitative evaluation of bacterial colonies in the root canals was performed based on the CFU/mL method, after different sterilization methods had been applied.
Results. A statistically significant reduction in the number of intracanal Enterococcus faecalis colonies, after a single and repeated 980 nm diode laser application, was confirmed. The first cycle of laser irradiation eliminated 52.5% of E. faecalis colonies, whereas the second application increased disinfection effectiveness to 87.6%.
Conclusion. The 980 nm diode laser demonstrated statistically significant antibacterial activity. High-power diode laser treatment might be considered as an adjunctive to conventional chemomechanical endodontic treatment.

Key words

Enterococcus faecalis, diode laser, 980 nm, endodontic disinfection

Słowa kluczowe

Enterococcus faecalis, laser diodowy, 980 nm, dezynfekcja endodontyczna

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