구강 질환 유발 미생물에 대한 항생작용을 갖는 천연물 추출물 검색

백동헌,Baek, Dong-Heon 한국미생물학회 2007 미생물학회지 Vol.43 No.3

구강청정제에 사용되는 많은 항미생물 성분들은 치주조직의 착색 및 작열감 등의 부작용을 가지고 있다. 이러한 취약점을 해결하고, 좀 더 생체친화적인 항미생물 물질을 찾기 위하여,한국식물추출물은행에서 소장하고 있는 2,125종의 식물추출물을 검색하였다. 항미생물 능력을 확인하기 위해, 잘 알려진 치과 병원균(치주질환 3종, 충치 1종)에 대한 성장억제 효과를 측정하였다. 대표적인 치주질환 유발세균인 Porphyromonas gingivalis에 대해서 19중의 식물 추출물이 항생효과를 나타내었으며, 17종이 Prevotella intermedia에 대해, 45종이 Haemophilus actinomycetemcomitans에 대해, 그리고 85종의 추출물이 충치 유발세균인 Streptococcus mutans 에 대해 효과를 나타내었다. 이중에서 총8종의 식물추출물이 실험에 사용한4종의 미생물 중 3종 이상에 대해 항생작용을 나타내었다. 또한 Cudrania tricuspidata, Morus bombycis와 Mallotus japonicas가 실험에 사용된 4종의 치과 병원균 모두에 대해 항생작용을 나타내어 치과용 재료 혹은 양치액에 항미생물 물질로 사용될 가능성을 나타내었다. Many of antimicrobial components used in the mouthwash have disadvantages such as coloring of periodontal tissue and homing sensation. To find the more biocompatible antimicrobial agent, we have screened the 2,125 kinds of natural plant extracts obtained from by the Plant Extract Bank (Daejeon, Korea). The antimicrobial activity was determined by spectrophotometric growth inhibition assay for the major dental pathogens. For the Porphyromonas gingivalis, 19 plant extracts had an antimicrobial activity, 17 plant extracts for the Prevotella intermedia, 45 plant extracts for the Haemophilus actinomycetemcomitans and 85 plant extracts for the Streptococcus mutans. Among these effective extracts, 8 kind of natural plant extracts had an antimicrobial activity for more than 3 species of dental pathogens. In our experiment, Cudrania tricuspidata, Morus bombycis and Mallotus japonicas have antibacterial effects on the all kinds of major dental pathogens. Therefore these plant extracts have a possibility to be a candidate for major antibacterial components in dental products.

T세포 특이항원인 4-1BB의 조직-특이 발현 조절에 관한 연구

백동헌,권병세,김각균 서울大學校 齒科大學 1997 齒大 論文集 Vol.21 No.2

연구논문 구연발표 : 정상 생리주기와 폐경기 농도의 여성호르몬이 치은섬유아세포와 치주인대세포의 ODF/OPG의 분비에 미치는 영향

신지연,백동헌,김태일,설양조,이용무,구영,류인철,정종평,한수부 대한치주과학회 2005 대한치주과학회 학술대회자료집 Vol.2005 No.2

Clinical Efficacy of Latex Cover for Dental Handpiece

이기호,백동헌,Lee, Ki-Ho,Paek, Dong-Heon Korean Academy of Orofacial Pain and Oral Medicine 2009 Journal of Oral Medicine and Pain Vol.34 No.3

The purpose of this study was to investigate the clinical efficacy of latex cover developed for dental handpiece on contamination of microorganisms during dental treatment and to determine whether it can be an alternative to conventional sterilization such as autoclaving. E. fecaelis was used as a experimental microorganism instead of oral flora. Experimental bowl with 2 cm of rectangular cavity was fabricated for handpiece operating instead of oral cavity. Latex covers ($Orokeeper^{(R)}$, Orobiotech Co., Korea) and several handpieces were used after sterilization by autoclave. Four experiments were performed to evaluate bacterial contamination related with (1) various parts of dental handpiece, (2) swabbing time with alcohol sponge, (3) postoperative air-water spraying time and (4) consecutive use of latex covers without autoclaving. The results show that face of handpiece uncovered with latex cover was severely contaminated than the covered area and that most bacteria were removed by swabbing face and head area of dental hand-piece and by air-water spraying more than 15 seconds nearly up to the level of sterilization. Conclusively it can be suggested that use of latex cover for handpiece during dental procedure, swabbing with alcohol sponge is air-water spraying for more than 15 seconds after use of dental handpiece should be very useful and practical for prevention of cross infection and should be an alternative method for the sterilization of dental handpiece under some difficult situations not being able to sterilize a handpiece with autoclave.

구강내 그람 양성세균에 대한 프로바이오틱 후보인 Streptococcus salivarius의 항균 활성

이성훈,백동헌 대한예방치과·구강보건학회 2022 大韓口腔保健學會誌 Vol.46 No.4

Objectives: The aim of this study is to investigate antimicrobial activity in isolated Streptococcus salivarius against Gram-positive bacteria related oral diseases. Methods: S. salivarius was used in G2, G7, K12, and ATCC 7073 strains and tryptic soy broth supplemented with glucose was cultivated. Actinomyces israelii , Actinomyces viscosus , and Enterococcus faecalis were cultivated with brain heart infusion broth. Streptococcus mutans and Streptococcus sobrinus were maintained using tryptic soy broth. The antimicrobial activity of S. salivarius was performed by minimum inhibitory concentration using the spent culture medium. Results: All S. salivarius have antimicrobial activity against Gram-positive bacteria in oral cavity. When comparing antimicrobial activity, S. salivarius G2 and G7 as isolated strain showed stronger antimicrobial activity against Gram-positive microbe than type K12 strain. Conclusions: S. salivarius G2 and G7 have strong antimicrobial activity and may be prevent oral disease by Gram-positive bacteria in oral cavity.

Comparison of Cariogenic Characteristics between Fluoride-sensitive and Fluoride-resistant Streptococcus mutans

옹승환,김종수,백동헌,유승훈 대한소아치과학회 2020 大韓小兒齒科學會誌 Vol.47 No.4

The aim of this study is to compare cariogenic characteristics of fluoride-sensitive Streptococcus mutans [fluoridesensitive (FS) S. mutans ] and fluoride-resistant Streptococcus mutans [fluoride-resistant (FR) S. mutans] in the presence of sucrose, and to evaluate its effect on cariogenic biofilm formation. S. mutans ATCC 25175 was continuously cultured in trypticase soy broth (TSB) containing NaF (70 ppm) for 40 days to generate FR S. mutans . FS and FR S. mutans were inoculated in TSB with or without 2% sucrose, and optical density and pH were measured every hour. An oral biofilm was formed using saliva bacteria and analyzed through confocal laser scanning microscopy and CFU count. Finally, the expression of glucosyltransferases genes of both S. mutans was investigated through RT-PCR. FR S. mutans exhibited slower growth and lower acidogenicity in the presence of sucrose compared to FS S. mutans . Both cariogenic and single species biofilm formation was lower in the presence of FR S. mutans , along with reduced number of bacteria. FR S. mutans showed significantly low levels of gtfB, gtfC, and gtfD expression compared to FS S. mutans . On the basis of results, FR S. mutans may be less virulent in the induction of dental caries.

Investigation of Efficacy of New Electrolyzed Water Generator for Oral Bacteria

조인우,남태계,백동헌 대한예방치과학회 2017 International Journal of Clinical Preventive Denti Vol.13 No.1

Objective: Electrolyzed water has antimicrobial activity against pathogenic bacteria. However, antimicrobial efficacy of electrolyzed water (EW) generator varies depending on the configuration and for of the electrodes. This study is to investigate antibacterial activity of new electrolyzed water generator against oral bacteria and biofilm. Methods: The EW was generated with eBio-cleaner, and the EW was treated on bacterial pellets after harvest of four oral bacteria. The EW treated bacteria were spread on agar plate and incubated at 37°C in anaerobic condition. Next, the salivary biofilm was formed using pooled saliva from the healthy donor. The salivary biofilm was treated with tap water, the EW and listerine, and the biofilm bacteria were spread on agar plate and were observed confocal laser microscope after live/dead staining. Results: The EW generated by eBio-cleaner has bactericidal activity against planktonic Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, and Streptococcus mutans. Listerine showed the strongest antimicrobial activity against planktonic bacteria. In case of biofilm experiment, the EW generated by eBio-cleaner showed disruptive and antimicrobial effect on the salivary biofilm. Whereas, listerine exhibited antimicrobial effect on the outside of biofilm. Conclusion: Take together of the results, the EW generated by eBio-cleaner may be helpful in preventing and treating dental caries and periodontitis by oral bacteria.

항-4-1BB항체와 반응하는 마우스 폐 조직-특이 cDNA클론의 분자생물학적 특성

최세원,김각균,백동헌 서울大學校 齒科大學 1996 齒大 論文集 Vol.20 No.2

Antifungal effect of electrolyzed hydrogen water on Candida albicans biofilm

표경열,유연승,백동헌 대한턱관절교합학회 2015 구강회복응용과학지 Vol.31 No.3

Purpose: Candida albicans can cause mucosal disease in many vulnerable patients. Also they are associated with denture-related stomatitis. Electrolyzed water is generated by electric current passed via water using various metal electrodes and has antimicrobial activity. The aim of this study was to investigate antifungal activity of electrolyzed water on C. albicans biofilm. Materials and Methods: C. albicans was cultured by sabouraud dextrose broth and F-12 nutrient medium in aerobic and 5% CO2 condition to form blastoconidia (yeast) and hyphae type, respectively. For formation of C. albicans biofilm, C. albicans was cultivated on rough surface 6-well plate by using F-12 nutrient medium in CO2 incubator for 48 hr. After electrolyzing tap water using various metal electrodes, the blastoconidia and hyphal type of C. albicans were treated with electrolyzed water. C. albicans formed blastoconidia and hyphae type when they were cultured by sabouraud dextrose broth and F-12 nutrient medium, respectively. Results: The electrolyzed water using palladium electrode (EWP) exhibited antifungal effect on blastoconidia of C. albicans. Also, the EWP significantly has antifungal activity against C. albicans biofilm and hyphae. In the electrolyzed water using various metal electrodes, only the EWP have antifungal activity. Conclusion: The EWP may use a gargle solution and a soaking solution for prevention of oral candidiasis and denture-related stomatitis due to antifungal activity.

Comparative study on bone regeneration between silk mat incorporated 4-hexylresorcinol and collagen membrane

석현,조유영,권해용,백동헌,김성곤 한국잠사학회 2017 International Journal of Industrial Entomology Vol.34 No.2

The purpose of this study was (1) to demonstrate the anti-microbial properties of 4-hexylresorcinol (4HR) loaded silk mat and (2) comparison of bone formation between 4HR incorporated silk mat and collagen membrane. Anti-microbial properties of 4HR incorporated silk mat was done after sterilization of silk mat (autoclaving and ethylene oxide gas). For the evaluation of bone formation, bilateral bony defects (size: 8 mm) were prepared in the parietal bone of the rabbits (n=10). 4HR incorporated silk mat (size: 10 x 10 mm) was applied on the right defect. For the comparative purpose, the same size of commercial collagen membrane was applied on the left defect. The anti-microbial properties of 4HR incorporated silk mat were maintained after sterilization process. When compared bone mineral density and bone volume, there was no statistically significant difference between groups at 4 weeks and 8 weeks after operation (p>0.05). In conclusion, 4HR incorporated silk mat could be autoclaved without concern of anti-microbial properties loss. In addition, 4HR incorporated silk mat showed similar bone regeneration to collagen membrane. Therefore, 4HR incorporated silk mat might be considered for the application of open membrane technique.