- 著者
- Yoshimi Kobayashi Makoto Hayashi Fumihiko Yoshino Muneaki Tamura Ayaka Yoshida Haruna Ibi Masaichi-Chang-il Lee Kuniyasu Ochiai Bunnai Ogiso
- 出版者
- 日本大学歯学部
- 雑誌
- Journal of Oral Science (ISSN:13434934)
- 巻号頁・発行日
- vol.56, no.1, pp.35-39, 2014 (Released:2014-03-15)
- 参考文献数
- 28
- 被引用文献数
- 2 12
Chemomechanical procedures can be used to eliminate bacteria from root canals. However, detectable bacteria sometimes remain because of the complexity of the root canal system. Endodontic passive ultrasonic irrigation (PUI) with hydrogen peroxide (H2O2) may be a promising option for increasing bactericidal hydroxyl radical (HO•) generation. In this in vitro experiment, we examined the effects of HO• generated using PUI and a low concentration of H2O2. An ultrasonic tip was submerged in 0.45 mol/L (1.5%) H2O2 in a microfuge tube. H2O2 was activated by an ultrasonic unit, the tip of which was kept centered in the tube, to mimic PUI. HO• generation was detected by electron spin resonance spectroscopy. An Enterococcus faecalis suspension in H2O2 was then preparedand activated as described above. Bactericidal effects were assessed by viable counting. Two-way analysis of variance and Tukey’s test were used to assess the statistical significance of differences among groups (P < 0.05). HO• generation and bactericidal activity were significantly increased by PUI in H2O2 in a time-dependent manner and were significantly higher than with H2O2 alone or with PUI in a Tris-HCl suspension. These results suggest that PUI in the presence of a low H2O2 concentration is a promising new disinfection strategy. (J Oral Sci 56, 35-39, 2014)