• Journal of Periodontal and Implant Science
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• v.43 no.1
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• pp.3-11
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• 2013

Periodontitis is a chronic inflammation of periodontal tissue caused by subgingival plaque-associated bacteria. Periodontitis has long been understood to be the result of an excessive host response to plaque bacteria. In addition, periodontal pathogens have been regarded as the causative agents that induce a hyperinflammatory response from the host. In this brief review, host-microbe interaction of nonperiodontopathic versus periodontopathic bacteria with innate immune components encountered in the gingival sulcus will be described. In particular, we will describe the susceptibility of these microbes to antimicrobial peptides (AMPs) and phagocytosis by neutrophils, the induction of tissue-destructive mediators from neutrophils, the induction of AMPs and interleukin (IL)-8 from gingival epithelial cells, and the pattern recognition receptors that mediate the regulation of AMPs and IL-8 in gingival epithelial cells. This review indicates that true periodontal pathogens are poor activators/suppressors of a host immune response, and they evade host defense mechanisms.

• Restorative Dentistry and Endodontics
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• v.28 no.4
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• pp.303-313
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• 2003

It has been documented that periodontopathic bacteria are also implicated in endodontic infections. 168 rDNA gene-directed PCR was to examine the prevalence of periodontopathic bacteria including Actinobacillus actinomycetemcomitans (Aa), Prevotella intermedia (Pi), Prevotella nigrescens (Pn), Porphyromonas gingivalis (Pg), Porphyromonas endodontalis (Pe), and Treponema denticola (Td) in the root canals of 36 endodontically infected teeth having apical lesions with or without clinical symptoms like pain, swelling, and fistula. 1. In 36 infected root canals, most frequently detected bacterial species was Pg (61.1%), followed by Td (52.8%) and Pe (38.9%). 2. Of 36 infected root canals, Aa was detected in 6 canals (16.7%) of the teeth, all of which showed clinical symptoms. 3. Of 36 infected root canals, Pi and Pn were found in 4 03.9%) and 5 (33.3%), respectively. Notably, prevalence of Pn in the symptomatic teeth was 50.0%. 4. One of black-pigmented anaerobic bacteria (BPB) including Pi, Pn, Pe, and Pg was detected in all of the teeth that showed pain or especially swelling but not fistula. It was, however, found that prevalence of BPB in the asymptomatic teeth or the teeth with fistula was only 40%. 5. Pe and Pg were detected in the teeth regardless of the presence or absence of symptoms. 6. Td was detected in the teeth regardless of the presence or absence of symptoms. High prevalence of BPB in the symptomatic teeth but low in the asymptomatic teeth suggests that BPB may play an important role in the pathogenesis of periapical lesions.

• 대한치주과학회:학술대회논문집
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• 2001.12a
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• pp.91-91
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• 2001

• International Journal of Oral Biology
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• v.46 no.3
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• pp.127-133
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• 2021

We previously showed that γ-glutamyltranspeptidase (GGT), an enzyme involved in glutathione metabolism, in Bacillus subtilis acts as a virulence factor for osteoclastogenesis via the RANKL-dependent pathway. Hence, it can be hypothesized that GGT of periodontopathic bacteria acts as a virulence factor in bone destruction. Because Fusobacterium nucleatum, which is a periodontopathic pathogen, has GGT with a primary structure similar to that of B. subtilis GGT (37.7% identify), the bone-resorbing activity of F. nucleatum GGT was examined here. Recombinant GGT (rGGT) of F. nucleatum was expressed in Escherichia coli and purified using the His tag of rGGT. F. nucleatum rGGT (Fn rGGT) was expressed as a precursor of GGT, and then processed to a heavy subunit and a light subunit, which is characteristic of general GGTs, including the human and B. subtilis enzymes. Osteoclastogenesis was achieved in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. Fn rGGT induced osteoclastogenesis to a level similar to that of B. subtilis rGGT; furthermore, osteoclastogenesis was induced in a dose-dependent manner. These results suggest that F. nucleatum GGT possesses a virulent bone-resorbing activity, which could play an important role in the pathogenesis of periodontitis.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.691-698
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• 2008

Purpose: Periodontal pathogens can invade the host tissue. Morphologic studies have revealed bacteria within the pocket epithelium, gingival connective tissues, alveolar bone, and oral epithelium. The objective of this study was to visualize and evaluate presence of Porphyromonas gingivalis and Tannerella forsythia in crevicular epithelial cells of periodontally healthy subjects and chronic periodontitis patients. Materials and Methods: A total of 666 crevicular epithelial cells in the samples obtained from 27 chronic periodontitis patients and 9 healthy volunteers were examined. Specific probes for P. gingivalis and T. forsythia and a universal probe for detection of all eubacteria targeting 168 rRNA for fluorescence in situ hybridization was used in conjunction with confocal laser scanning microscopy. Results: 98.99% of sulcular epithelial cells from healthy volunteers and 84.40% of pocket epithelial cells from periodontitis patients were found to harbor bacteria. P. gingivalis and T. forsythia were discovered more often in crevicular epithelial cells from periodontitis patients. Conclusion: P. gingivalis and T. forsythia can invade crevicular epithelial cells and intracellular bacteria may act as a source of bacteria for persistent infection.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.494-503
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• 2008

Real-time PCR 기법을 이용하여 구강내 치태에서 특정 세균의 존재여부를 알 수 있을 뿐 아니라 정량적 분석이 가능하게 되었다. 이 연구는 real-time PCR 기법을 이용하여 8-18세의 청소년에서 치주질환 원인균의 조성을 알아보고자 전신질환이 없는 어린이 및 청소년 65명을 대상으로 치은연하의 치태를 채취하여 5종의 치주질환 원인균의 출현율과 그 양을 측정하고, 또한 함께 측정한 치태지수 및 치은지수와의 상관관계를 조사하여 다음과 같은 결론을 얻었다. 1. 치태지수의 평균은 1.33이었으며, 치은지수의 평균은 0.97이었다. 치태지수는 나이가 증가할수록 낮아졌다(p<0.05). 2. 치주질환 원인균의 출현율은 P. gingivalis 61.5%, T. forsythia 53.8%, T. denticola 29.2%, A. actinomycetemcomitans 15.4%, F. nucleatum은 100%였다. P. gingivalis, T. denticola는 10세 이후 출현율이 증가하였고 A. actinomycetemcomitans는 8-10세 군에서 출현율이 높았다(p<0.05). 3. 정량적 분석에서 치태지수와 치은지수는 F. nucleatum의 양과 유의한 상관성이 있었으며, 치태지수는 치은지수와 유의한 상관성이 있었다. T. forsythia는 A. actinomycetemcomitans, T. denticola양과 강한 상관성을 보였으며, T. denticola양과 A. actinomycetemcomitans도 강한 상관관계를 가지고 있었다.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.45-55
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• 2007

Plant extract has attracted considerable interest in oral disease therapy. The present study was performed to observe the antibacterial effect on cariogenic Streptococcus mutans GS5 and Streptococcus sobrinus 6715, and periodontopathic Actinobacillus actinomycetemcomitans Y4 of phytoncide from Chamaecyparis obtusa Sieb. et Zucc employing the measurement of optical density, viable cell counts, and antibiotic sensitivity. The results were as follows: 1. Minimum inhibitory concentration of the phytoncide for S. mutans, S. sobrinus, and A. actinomycetemcomitans was observed to be 0.5%, 1%, and 0.2%, respectively. 2. Minimum bactericidal concentration of the phytoncide for S. mutans, S. sobrinus, and A. actinomycetemcomitans was determined to be 0.5%, 2%, and 0.2%, respectively. 3. The bacteria exposed to the phytoncide become more sensitive to antibiotics. The phytoncide enhanced significantly antibacterial activity of ampicillin against S. mutans and S. sobrinus. It also increased significantly the activity of penicillin and amoxicillin against S. sobrinus. In contrast, the phytoncide augmented the activity of amoxicillin and cefotaxime against A. actinomycetemcomitans but the increase was not statistically significant. The overall results indicate that phytoncide from Chamaecyparis obtusa Sieb. et Zucc used for this study has a strong antibacterial activity against cariogenic and periodontopathic bacteria and that it also has permeabilizing effect on certain antibiotics against these bacteria. Therefore, the phytoncide may be used as a candidate for prevention and therapeutic agent against oral infectious disease including dental caries and periodontal disease.

• Journal of Periodontal and Implant Science
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• v.51 no.4
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• pp.226-238
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• 2021

Purpose: Although several reports have described the relationship between periodontal disease and cardiovascular disease, information about the association between periodontal disease and the progression of degenerative aortic stenosis (AS) is lacking. Therefore, we performed a retrospective, single-center, pilot study to provide insight into this potential association. Methods: Data from 45 consecutive patients (19 men; median age, 83 years) with mild or moderate degenerative aortic stenosis were analyzed for a mean observation period of 3.3±1.9 years. The total amount of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis and titers of serum immunoglobulin G (IgG) against periodontal bacteria and high-sensitivity C-reactive protein (hs-CRP) were evaluated. Aortic valve area (AVA), maximal velocity (Vmax), mean pressure gradient (mean PG), and the Doppler velocity index (DVI) were evaluated. The change in each parameter per year ([Parameter_LATEST-Parameter_BASELINE]/Follow-up Years) was calculated from the retrospective follow-up echocardiographic data (baseline vs. the most recently collected data [latest]). Results: No correlation was found between the concentration of periodontopathic bacteria in the saliva and AS status/progression. The anti-P. gingivalis antibody titer in the serum showed a significant positive correlation with AVA and DVI. Additionally, there was a negative correlation between the anti-P. gingivalis IgG antibody titer and mean PG. The hs-CRP concentration showed positive correlations with Vmax and mean PG. Meanwhile, a negative correlation was observed between the anti-P. gingivalis IgG antibody titer and ΔAVA/year and Δmean PG/year. The hs-CRP concentration showed positive correlations with Vmax and mean PG, and it was significantly higher in patients with rapid aortic stenosis progression (ΔAVA/year <-0.1) than in their counterparts. Conclusions: Our results suggest that periodontopathic bacteria such as A. actinomycetemcomitans and P. gingivalis are not directly related to the status/progression of degenerative AS. However, inflammation and a lower immune response may be associated with disease progression.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.170-178
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• 2011

The purpose of this study was to assess the prevalence of periodontopathic bacteria and resistance determinants from oral biofilm of children. Subgingival dental plaque was isolated from 87 healthy children, and PCR was performed to determine the presence of 5 periodontal pathogens including P. gingivalis, T. forsythia, T. denticola, F. nucleatum, A. actinomycetemcomitans, and nine resistance genes including tet(Q), tet(M), ermF, aacA-aphD, cfxA, $bla_{SHV}$, $bla_{TEM}$, vanA, mecA. 1. The prevalence of F. nucleatum, T. forsythia. and P. gingivalis was 95.4%, 55.2%, and 40.2%, respectively. In addition. the prevalence of A. actinomycetemc omitans was 5.7%, while T. denticola was 3.4%. 2. In analysis of antibiotic resistance determinants. cfxA, $bla_{TEM}$ and tet(M) were detected in all the samples tested. It was also found that the prevalence of tet(Q) showing tetracycline resistance. $bla_{SHV}$ associated with resistance to ${\beta}$-lactams, ermF exhibiting erythromycin resistance, and, vanA resulting vancomycin resistance was 88.5%, 29.9% 87.4%, and 48.5%, respectively. The aacA-aphD gene showing resistance to aminoglycosides and mecA gene harboring methicillin resistance exhibited the lowest prevalence with 9.2%. 3. In a correlation analysis between periodontopathic pathogens and antibiotic resistance determinants, it was found that there was a significant correlation between T. forsythia and $bla_{SHV}$. Also, P. gingivalis and vanA showed a correlation. Finally, tet(Q) and ermF showed a significant correlation (phi: 0.514) while mecA and vanA also showed a correlation(phi: 0.25).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.187-193
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• 2014

Dental caries are one of the most common oral diseases and Streptococcus mutans (S. mutans) plays an important role in the initiation and progression of dental caries. Oral malodor is primarily the result of microbial metabolism such as Porphyromonas gingivalis (P. gingivalis) that produce volatile sulfur compounds (VSCs), causing oral malodor. Prevotella intermedia (P. intermedia) is known as typical periodontopathic bacteria, and periodontal disease is chronic inflammatory disease that leads to damage of gingival connective tissue and alveolar bone, eventually loss of teeth. In this study, we investigated antimicrobial effect of mouthwash containing cetylpyridinium chloride (CPC), sodium fluoride (NaF), green tea water extract and pine needles water extract against cariogenic and periodontopathic bacteria sucn as S. mutans, P. gingivalis and P. intermedia. As a result, the reduction ratios of S. mutans and P. gingivalis were 4.00 Log and 4.68 Log reduction for 30 s, and P. intermedia were 2.40 Log reduction for 30 s and 2.70 Log reduction for 60 s. Dentocult SM Strip mutans (SM Strip) provides easy detection of visual data showing a significant inhibition on S. mutans. In conclusion, we expected that mouthwash containing CPC, NaF, green tea water extract and pine needles water extract could help preventing the dental disease like dental caries and oral malodor.