INVESTIGATION OF ANTIBACTERIAL ACTIVITY OF ND: YAG - LASER AND STANDARD ENDODONTIC TREATMENT

Abstract

Introduction: The microbial infection is one of the main causes of the dental pulp and periodontal diseases. Previously used methods for its elimination are not fully effective, and often some microorganisms in root canals (RC) remain unaffected after treatment. Another modern method for disinfection of root canal system is laser disinfection. Different types of lasers are used - Nd: YAG, Er: YAG, Diode laser. Purpose: The purpose of our study is to compare the antibacterial activity of ND: YAG laser and conventional endodontic therapy in the treatment of infected root canals. Materials and methods The study involved 36 teeth of patients diagnosed with pulp gangrene or chronic periapical periodontitis, requiring endodontic treatment. They were divided into two groups of 18 teeth each one. The teeth in both groups are prepared by Protaper Universal rotary instruments (Maillefer Instruments SA, Ballaigues, Switzerland). In group 1the root canals disinfection is performed with a Nd: YAG laser (source of Nd: YAG laser (1064 nm) is the AT Fidelis - Fotona d.d., Ljubljana laser system). In group 2 was used the following protocol of root canal disinfection: 2.5% sodium hypochlorite solution and 17% EDTA divided by irrigation with distilled water. Then a sterile paper point is placed in the root canals, and a microbiological sample is taken again. Results: In all compared pairs, there was no significantly different effect regarding the number of microorganisms. Conclusions: The disinfection rinsing method with NaOCl has the strongest antimicrobial effect in clinical studies (90% against all microbial isolates). The use of Nd: YAG laser independently is not always sufficient for root canal disinfection - the effect is about 66%.