Background /Aim: The antibacterial effect was assessed by dead/live technique by conjunction between chitosan nanoparticle and diode laser (970nm), were chitosan has an excellent biocompatibility with tissues; save to human with no side effect; excellent bioactivity effect; chelation ability, good absorptive capacity, and antimicrobial activity regarding gram-positive and gram-negative bacteria. The studies have showed chitosan mechanism action related to the films formed around the cell which prevents nutrients absorption. Other res,earch indicates that, using laser radiation in the treatment of dental hard tissue and helping in the root canal formation, the addition effects of diode laser is bacteriostatic effect on bacterial strains present in root canal. The laser radiation was transmitted through quartz optical fibers, which could introducing laser light inside root canal, around canal curvatures and irregularities more easily. Throughout this review the aim of our study is present and discuss the antimicrobial activity of chitosan nanoparticles in combination with diode laser against oral bacteria especially the E.coli and aimed for developing commercial products such as an irrigant solution for root canal. The aim of this study was to estimate the ability of 970-nm diode laser to disinfection in combination with chitosan nanoparticlesagainst negative charged E.coli bacterial strain
Materials and methods: The root canals of 40 extracted single-rooted incisors teeth were prepared by rotary system. After crown removal, the roots were autoclaved. The teeth were inoculated with E. coli suspension for two weeks. The samples were divided into four groups (n=10). The samples of the first group G1 (n=10) were inoculated with bacteria only as control group, the second group G2 (n=10) were inoculated with bacteria & chitosan, the group will be divided in 2 subgroup according to the time of incubation (60 seconds, 90 seconds) (n=5). The third group G3 were inoculated with bacteria and treated with a 970-nm diode laser, the group will be divided in 2 subgroup according to the time of laser irradiation (60 seconds, and 90 seconds) (n=5). The fourth group G4 (n=10) were inoculated with bacteria &chitosan and treated with diode laser, the group will be divided in 2 subgroup according to the time of laser irradiation (60 seconds, and 90 seconds) (n=5). Bacterial samples were taken from the root canals and the cultivation. was carried out. The standard deviation of colony-forming units (CFU) for each specimen were measured to compare the reduction in CFU in each group.
Results: low mean CFU/mL is recorded in Group2 (chitosan with laser) followed by Group3 (chitosan) and Group 4 (laser), respectively. The difference in CFU/mL between the three groups is statistical significant (P ≤ 0.05).
Conclusion: The results of this research show that 970-nm diode laser in combination with chitosan nanoparticles could be used as a complementary disinfection device in root canal treatment and ability to increase the success rate in endodontic therapy.