著者
Yoriyuki Hirano Makoto Hayashi Muneaki Tamura Fumihiko Yoshino Ayaka Yoshida Mitsuaki Masubuchi Kenichi Imai Bunnai Ogiso
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.18-0455, (Released:2019-10-05)
参考文献数
39
被引用文献数
10

Oral diseases generally have certain bacteria associated with them. Non-thermal atmospheric pressure plasma (NTAP), generated at atmospheric pressure and room temperature, incorporates several molecules, including reactive oxygen species, that can inactivate various bacteria including oral pathogens. For this reason, several NTAP devices have been developed to treat oral diseases. Use of noble gases can enhance the bactericidal efficacy of NTAP, but this requires additional gas supply equipment. Therefore, a new NTAP device that employs ambient air as the working gas was developed. The device generates non-thermal atmospheric pressure air plasma. Here, the singlet oxygen (1O2) levels generated, their bactericidal effects on oral pathogens (Streptococcus mutans, Porphyromonas gingivalis, and Enterococcus faecalis), and the bacterial oxidative stress they imposed were measured. 1O2 generation in phosphatebuffered saline was assessed qualitatively using electron spin resonance (ESR) spectroscopy, and bactericidal efficacy was evaluated by counting of colony-forming units/mL. Bacterial oxidative stress was determined by measurement of hydrogen peroxide (H2O2) and superoxide dismutase (SOD) activity. ESR indicated that the level of 1O2 increased significantly and time-dependently, and was inversely correlated with distance, but the bactericidal effects were correlated only with treatment time (not distance) as H2O2 increased and SOD levels decreased, suggesting that the new device has potential applicability for treatment of oral disease.
著者
Hisashi Suguro Osamu Takeichi Makoto Hayashi Teinosuke Okamura Akiko Hira Yoriyuki Hirano Bunnai Ogiso
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0092, (Released:2018-04-16)
参考文献数
25
被引用文献数
4

Transparent epoxy resin root canal models were used to evaluate vertical condensation techniques for obturating lateral canals. The root canal model was configured with a straight main root canal and four right-angled lateral canals at 1.0 and 3.0 mm from the apex. Root canal obturation was performed with Thermafil, Obtura II, or NT condenser. Obturation volume in lateral canals was measured by three-dimensional microcomputed tomography, and one-way analysis of variance was used to analyze differences between groups. Lateral canals at 1.0 and 3.0 mm were uniformly filled by all obturation methods. Among the three obturation methods, Thermafil resulted in the highest obturation volumes for all lateral canals.
著者
Tamotsu Tsurumachi Yoriyuki Hirano Akiko Hira Yasuyo Aida 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.57, no.2, pp.157-160, 2015 (Released:2015-06-10)
参考文献数
10
被引用文献数
7

When a primary tooth sustains a traumatic injury, development of the permanent tooth can be disturbed, leading to various malformations. This case report details the 7-year follow-up of a developmental anomaly of a central mandibular incisor in a 10-year-old Japanese girl with a history of dental trauma that had occurred at age 4. The trauma had resulted in unusual crown dilaceration in the permanent successor, which exhibited a discoloured and abnormal crown morphology. Radiographic examination revealed crown dilaceration of the tooth, which had a curved root canal. (J Oral Sci 57, 157-160, 2015)
著者
Yusuke SUZUKI Makoto HAYASHI Takuya YASUKAWA Hiroshi KOBAYASHI Kosuke MAKINO Yoriyuki HIRANO Shozo TAKAGI Laurence C. CHOW Bunnai OGISO
出版者
日本歯科理工学会
雑誌
Dental Materials Journal (ISSN:02874547)
巻号頁・発行日
pp.2014-255, (Released:2015-02-25)
参考文献数
31
被引用文献数
5

Aim of this study was to develop a novel fluorapatite-forming calcium phosphate cement (FA-CPC) with tricalcium silicate (TCS) for endodontic applications and to examine its in vitro and in vivo characteristics. The FA-CPC powder consisted of 62.8% CaHPO4, 30.8% CaCO3, and 6.4% NaF. One part of TCS was combined with 9 parts of FA-CPC powder (FA-CPC with TCS). A 1.5 M phosphate solution was used as cement liquid. Setting time (ST), diametral tensile strength (DTS), phase composition by X-ray diffraction (XRD), and cement alkalinity were analyzed. Cement biocompatibility was assessed using rat subcutaneous model. Cement ST was 10.3±0.6 min and DTS was 3.89±0.76 MPa. XRD patterns showed that highly crystalline apatitic material was the only significant phase present and pH value was approximate 11.0. FA-CPC with TCS demonstrated similar biocompatibility as that of mineral trioxide aggregate control. These results suggest that FA-CPC with TCS may be useful for endodontic applications.