• 대한치과교정학회지
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• 제53권6호
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• pp.345-357
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• 2023

Enamel demineralization represents the most prevalent complication arising from fixed orthodontic treatment. Its main etiology is the development of cariogenic biofilms formed around orthodontic appliances. Ordinarily, oral biofilms exist in a dynamic equilibrium with the host's defense mechanisms. However, the equilibrium can be disrupted by environmental changes, such as the introduction of a fixed orthodontic appliance, resulting in a shift in the biofilm's microbial composition from non-pathogenic to pathogenic. This alteration leads to an increased prevalence of cariogenic bacteria, notably mutans streptococci, within the biofilm. This article examines the relationships between oral biofilms and orthodontic appliances, with a particular focus on strategies for effectively managing oral biofilms to mitigate enamel demineralization around orthodontic appliances.

• International Journal of Oral Biology
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• 제39권3호
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• pp.137-143
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• 2014

Dental professionals are repeatedly exposed to many microorganisms present in both blood and saliva. Thus, dental professionals are at a greater risk of acquiring and spreading infections, and the implementation of infections control guidelines is necessary. Cellular phones have become a necessary device for communicating in hospitals. Cellular phones contaminated with bacteria may serve as a fomite in the transmission of pathogens by the hands of medical personnel. Nevertheless, studies about rate and levels of bacterial contamination of cellular phones have been extremely limited with regards to dental personnel. The purpose of this study was to identify bacterial flora on the cellular phones of dentists by a molecular biological method using the 16S rRNA cloning and sequencing method. We acquired total 200 clones from dentists' cell phones and identified the bacterial species. Pseudomonas (34.6%), Lactobacillus (18.5%), Azomonas (11.5%), and Janthinobacterium (6%) were the dominant genera on dentists' cell phones. The oral bacteria identified were Anaerococcus lactolyticus, Gibbsiella dentisursi, Lactobacills leiae, Streptococcus mitis, Streptococcus oligofermentans, and Streptococcus sanguinis. Pathogenic bacteria and opportunistic pathogens such as Carnobacterium funditum, Raoultella planticola, Shigella flexneri, Lactobacillus iners, Staphylococcus aureus, and Staphylococcus epidermidis were also identified.

• International Journal of Oral Biology
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• 제38권2호
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• pp.55-59
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• 2013

TM7 is an uncultivated organism which is present in extremely diverse environments. Members of the Dialister genus are difficult to culture as a result of which many of these strains remain uncultivated. It has been suggested that TM7 and Dialister bacteria may belong to a group of suspected periodontal pathogens. In our current study, the presence of the sebacteria in Korean dental plaque samples was assessed using PCR detection methods with specific primers for 16S ribosomal RNA genes. The experimental group included 84 volunteers (35 males and 49 females). Plaque samples were collected from 4 non-adjacent proximal sites of the molar areas of the mandible in each subject and pooled. TM7 was detectable in 56% and the Dialister genus in 27.5% of the volunteers. Both TM7 and Dialister were present in 20.3% of volunteers. We found that 36.9% of the volunteers were negative for both bacteria. Further studies to evaluate the prevalence of these putative pathogenic bacteria in the Korean population are warranted.

• Journal of Oral Medicine and Pain
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• 제44권3호
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• pp.133-139
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• 2019

Osteomyelitis is an inflammatory condition of the bone caused by pathogenic bacteria. The causative pathogen is usually oral residing bacteria, but this is a report of patients with osteomyelitis infected with Enterobacteriaceae, which is not common. Enterobacteriaceae has been known to cause in-hospital infections for over last 30 years and is known to have multiple antibiotic resistances. Both cases in this study developed osteomyelitis after removal of the dentigerous cyst. Enterobacter aerogenes was cultured in one patient and Serratia marcescens in the other. After changing antibiotics through antibiotic susceptibility testing, clinical symptoms subsided and radiographic images confirmed that the callus formed and recovered at the same time.

• International Journal of Oral Biology
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• 제38권4호
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• pp.141-147
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• 2013

It has been established that berberine has strong antimicrobial effects. Little is known however regarding the antimicrobial activity of berberine against endodontic pathogenic bacteria or its cytotoxicity in human oral tissue cells. The antibacterial properties of berberine were tested against 5 strains of Enterococcus faecalis and type strains of Aggregatibacter actinomycetemcomitans, Prevotella nigrescens, Prevotella intermedia, and Tannerella forsythia, which are involved in endodontic infections. Antimicrobial activity was evaluated through minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) measurements. The viability of normal human gingival fibroblast (NHGF) cells after exposure to berberine was measured using a methyl thiazolyl tetrazolium (MTT) assay. The data showed that berberine has antimicrobial effects against A. actinomycetemcomitans with an MIC and MBC of $12.5{\mu}g/ml$ and $25{\mu}g/ml$, respectively. In the cytotoxicity studies, cell viability was maintained at 66.1% following exposure to $31.3{\mu}g/ml$ berberine. Overall, these findings suggest that berberine has antimicrobial activity against the tested bacteria. Nevertheless, lower concentrations in combination with other reagents will need to be tested before these in vitro results can be translated to clinical use.

• 대한한의학회지
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• 제25권4호
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• pp.121-128
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• 2004

Objective : The aim of this work is to investigate the antibacterial activity of the essential oil obtained from Artemisia capillaris (A. capillaris), as the development of microbial resistance to antibiotics make it necessary to constantly look for new and active compounds effective against pathogenic bacteria. Methods : The crushed materials of A. capillaris (1 kg) were subjected to steam distillation for 3 h, using a modified Clevenger type apparatus in order to obtain essential oil. Diethyl ether was the extracting solvent kept at 25°.... The essential oil was analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The essential oil and the composition were tested for antimicrobial activities against 15 different genera of oral bacteria. Results and Conclusion : The components of the essential oil identified were: β-pinene (9.36%), camphor (3.32%), 1,8­cineole (4.38%), artemisia alcohol (3.32%), β-caryophyllene (11.08%), γ-cadinene (4.23%), and capillene (32.74%). The essential oil of A. capillaris exhibited considerable inhibitory effects against all oral bacteria tested, while their major components demonstrated various degrees of growth inhibition.

• 생약학회지
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• 제54권1호
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• pp.27-37
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• 2023

This research was conducted to investigate the comprehensive effects of methanol extract of Coptidis rhizoma (MECR) against oral pathogen. We studied the antibacterial, anti-biofilm, anti-gingipain and anti-inflammatory activity of MECR. The minimum bactericidal concentration (MBC) of MECR was 100 ㎍/mL against several oral pathogens. The formation of biofilm of Streptococcus mutans was reduced to 8.93~24.12% in the presence of 25 ㎍/mL of MECR. The gingipain activity of Porphyromonas gingivalis were reduced to 3.91~6.23% in case of Kgp and 5.73~7.78% in case of Rgp in the presence of 10 mg/mL of MECR. The expression of fadA mRNA, virulence factor of Fusobacterium nucleatum (F. nucleatum) was 3 folds decreased in the presence of 25 ㎍/mL of MECR. In case of YD-38 cells challenged with F. nucleatum, RQ values of IL-8 and IL-6 were reduced about 12 folds and 5.45 folds in the presence of 2 ㎍/mL of MECR. In case of RAW 264.7 murine cell challenged with F. nucleatum, RQ values of IL-1β and IL-6 were 2.52 folds and 2.55 folds reduced in the presences of 2 ㎍/mL of MECR. Conclusively, MECR showed potent antibacterial and anti-inflammatory effects against oral pathogenic bacteria.

• 대한소아치과학회지
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• 제36권1호
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• pp.1-11
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• 2009

Essential oil은 식물로부터 추출한 휘발성의 호지방성 화합물로서 essential oil은 잠재적으로 항균, 항진균, 진경련, 항말라리아성, 곤충퇴치능력 등의 생물학적 효과를 가지고 있다. 본 연구에서는 다양한 방향식물에서 추출한 Citral, Pineole, Linalool, Eugenol, Limonene, Pinene 등으로 구성된 다섯종류의 essential oil을 사용하였으며, 여덟 군의 중요한 병원성 세균인 Streptococcus mutans(S. mutans), Staphylococcus aureus(S. aureus), Streptococcus sanguis(S. sanguis), Streptococcus anginosus(S. anginosus), Actinobacillus actinomycetemcomitans(A. actinomycetem- comitans), Streptococcus sobrinus(S. sobrinus), Staphylococcus epidermidis(S. epidermidis), Esherichia coli (E. coli)에 대한 저항성으로서 항균능력을 평가하였다. Essential oil의 항균능력은 용액희석방법을 사용하여 검사하였으며, essential oil 농도범위는 10 mg/mL, 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.625 mg/mL, 0.516 mg/mL, 0.3125 mg/mL, 0.078 mg/mL, 0.039 mg/mL, 그리고 0.015 mg/mL였다. Essential oil은 용량 의존적으로 시험 균주의 성장을 효과적으로 억제하였으며, NM을 제외하고 R, LG, FR, O oil은 저농도에서 구강 병원성 미생물의 성장을 억제하였다. 또한 사용된 essential oil은 E.coli와 S. epidermidis의 성장에는 탁월한 억제효과를 보이지는 못했으나 구강 병원성 미생물에 대해서는 특별한 성장 억제효과를 나타냈다.

• 한방안이비인후피부과학회지
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• 제17권3호
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• pp.33-37
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• 2004

Objective: The aim of this work is to investigate the antibacterial activity of the Sohporaflavanone G isolated from Sophora flavescens (S. flavescens), as the development of microbial resistance to antibiotics make it essential to constantly look for new and active compounds effective against pathogenic bacteria. Method : Sophoraflavanone G was isolated from the dried roots of Sophora flavescens Aiton (Leguminosae) by bioassay?guided fractionation. We investigated the effect of sophoraflavanone G on oral bacterial at various concentrations after incubation of 24 h in strains in the dose?dependent manner. Results: The structure of active compound, Sophoraflavanone G having a lavandulyl group at C?8, was elucidated on the basis of spectral data especially 1H?NMR and I3C?NMR. The antimicrobial activity showed that Sophoraflavanone G exhibited antimicrobial activilies against all the bacteria tested (MICs, 0.39 - 6.25 ㎍／ml). Sophoraflavanone G showed the strong antimicrobial activity against all the facultative bacteria and microaerophilic bacteria (MICs, 0.78 - 1.56 ㎍／ml) and also Sophoraflavanone G showed the strong antimicrobial activity against obligate anaerobic bacteria (MICs, 0.39 - 6.25 ㎍／ml).