著者

Watcharapong TONPRASONG Masanao INOKOSHI Muneaki TAMURA Keita HATANO Shunsuke MINAKUCHI

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

vol.42, no.1, pp.49-54, 2023-01-25 (Released:2023-01-31)

参考文献数

31

被引用文献数

2

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Although a surface pre-reacted glass ionomer (S-PRG) exerts a suppressive effect on Candida albicans (C. albicans) activity and growth, its influence on the expression of the lipase gene (LIP) family including LIP1–LIP10, an indicator of clinical infection, has not yet been investigated. Therefore, in this study, we evaluated the effect of S-PRG filler eluates on LIP expression in C. albicans using real-time reverse-transcription polymerase chain reaction. Candida albicans was treated with an S-PRG filler diluted at ratios of 1:32 and 1:64 for 24 h at 37°C. The diluted S-PRG filler eluates (1:32) suppressed lipase activity in C. albicans by downregulating LIP5 (0.54±0.25 relative to that of the control) and LIP8 (0.35±0.074) expression after 24 h, which corresponded with decreased lipase activity. At a dilution factor of 1:64, there was no significant difference in LIP expression. Thus, the S-PRG filler eluate has potential to suppress fungal activity by downregulating LIP expression.

著者

Takeshi NAKAMURA Makoto HAYASHI Muneaki TAMURA Masahiro KAKETANI Tomoka ITO Toshiki TAKAMIZAWA Yusuke SUZUKI Takuya YASUKAWA Akiyoshi SUGAWARA Osamu TAKEICHI

出版者

The Japanese Society for Dental Materials and Devices

雑誌

Dental Materials Journal (ISSN:02874547)

巻号頁・発行日

pp.2022-250, (Released:2023-03-18)

参考文献数

32

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The recently developed biphasic calcium phosphate cement (BCPC) consists of α-tricalcium phosphate-tetracalcium phosphate as the solid phase and calcium phosphate solution as the liquid phase. BCPC powder is composed of a single solid solution with a monomodal size distribution. Here, we used a bacterial leakage model to examine the utility of BCPC as a seal for root-end filling. We prepared large (median particle size=9.96 µm; BCPC-L) and small (median particle size=4.84 µm; BCPC-S) BCPC powders. In total, 45 single-rooted teeth were instrumented, resected at the root-end, and retrofilled with experimental materials. Mineral trioxide aggregate (MTA) was used as the control. After visual confirmation of BCPC powder size and retrofilling quality by microscopy, bacterial leakage tests were conducted using Enterococcus faecalis. The bacterial leakage tests did not reveal any significant differences between BCPC-S and MTA. Our findings suggest that BCPC-S is useful for root-end filling.

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

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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

Mariko Ohtsu Muneaki Tamura Hideto Sasaki Shuichi Sato Masatake Asano

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.59, no.3, pp.453-456, 2017 (Released:2017-09-14)

参考文献数

16

被引用文献数

1

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The effects of bittern water (BW), obtained from the ocean floor, on cariogenic bacteria and saliva secretion were examined. Streptococcus mutans was mixed with BW for 1, 3, 5, 10, and 20 min to explore the bactericidal effects of BW against cariogenic bacteria. Bacterial viability was calculated by counting the number of colony-forming units on Brain Heart Infusion agar plates. The results indicated a bacterial viability of more than 35% even after 20 min of incubation. Subsequently, the effects of BW on saliva secretion and the salivary concentration of secretory IgA (sIgA) were examined. Gargling with BW significantly augmented saliva secretion. Although the sIgA concentration was reduced, the total sIgA secreted into saliva was increased significantly. Our findings indicate that the use of BW may be a new strategy for the treatment of various oral diseases, including dry mouth.

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

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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)