The prevalence of novel periodontal pathogens and bacterial complexes in Stage II generalized periodontitis based on 16S rRNA next generation sequencing

Abstract Objective: To define the subgingival microbial profile associated with Stage II generalized periodontitis using next-generation sequencing and to determine the relative abundance of novel periodontal pathogens and bacterial complexes. Methodology: Subgingival biofilm samples were collected from 80 subjects diagnosed with Stage II generalized periodontitis. Bacterial DNA was extracted, and 16S rRNA-based bacterial profiling via next-generation sequencing was carried out. The bacterial composition and diversity of microbial communities based on the age and sex of the patients were analyzed. The bacterial species were organized into groups: bacterial complexes (red, orange, purple, yellow, and green), novel periodontal pathogens, periodontal health-related species, and unclassified periodontal species. The results were analyzed and statistically evaluated. Results: The highest number of bacteria belonged to the phylum Bacteroidetes and Firmicutes. In terms of relative abundance, the orange complex represented 18.99%, novel bacterial species (Fretibacterium spp. and Saccharibacteria spp.) comprised 17.34%, periodontal health-related species accounted for 16.75% and unclassified periodontal species represented (Leptotrichia spp. and Selenomonas spp.) 15.61%. Novel periodontal pathogens had outweighed the periodontal disease-related red complex (5.3%). The one-sample z-test performed was statistically significant at p<0.05. The Beta diversity based on the unweighted UniFrac distance at the species level demonstrated a total variance of 15.77% based on age and 39.19% on sex, which was not statistically significant. Conclusion: The bacterial species corresponding to the disease-related orange complex and novel periodontal pathogens are predominant in Stage II generalized periodontitis.

The relationship between maternal periodontal disease and preterm low birth weight / 口腔疾病防治

@# Preterm low birth weight newborns are prone to complications during growth and development, such as growth retardation and infectious diseases, and the mortality rate of high-risk infants is higher than that of healthy newborns. Epidemiological data show that periodontal disease in pregnant women is correlated with preterm low birth weight. Periodontal disease in pregnant women is one of the risk factors for adverse pregnancy outcomes, such as  preterm   low birth weight. This paper addresses the correlation between maternal periodontal disease and  preterm  low birth weight, the influence of periodontal treatment on the incidence of preterm  low birth weight, and premature birth caused by maternal periodontal disease. The mechanism of infant weight is reviewed. The results of this review show that the current studies confirm the correlation between maternal periodontal disease and  preterm low birth weight. However, the causal relationship between maternal periodontal disease and preterm  low birth weight is not fully elucidated, and the specific mechanism and approach are not clear. A possible mechanism is that periodontal pathogens in pregnant women pass through the placental barrier to influence pregnancy outcomes. Therefore, more in-depth research is needed on the specific mechanism, approach, intervention and treatment based on the relationship between these two factors.

Study on periodontal status of patients with pre-diabetes / 中华口腔医学杂志

Objective@#To investigate periodontal status of patients with pre-diabetes and evaluate the prevalence of periodontal pathogens in oral cavity.@*Methods@#All the subjects were under regular care in urban area of Beijing, including 88 subjects with normal blood glucose (normal blood glucose group), 27 pre-diabetic patients (pre-diabetic group), 58 well-controlled diabetic patients (glucose well controlled group) and 72 poor-controlled diabetic patients (glucose poor controlled group). Whole unstimulated saliva samples were collected before periodontal examination. Periodontal parameters, including plaque index (PLI), probing depth (PD), bleeding index (BI), bleeding on probing (BOP) and clinical attachment loss (CAL), were examined at mesial-buccal and distal-lingual sites of each tooth. Number of missing teeth was recorded. DNA was extracted from the salivary deposition, Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Campylobacter rectus (Cr), and Prevotella nigrescens (Pn) were detected by using PCR method based on 16SrRNA. Periodontal status and prevalence and quantity of the pathogens under various blood glucose states were compared.@*Results@#The PD scores of four groups had no statistical differences. The CAL [(2.29±1.35) mm] and the number of missing teeth[2.0 (7.0)] in pre-diabetic group were significantly lower than that in glucose poor controlled group [(3.07±1.45) mm, P=0.04 and 5.0 (10.0), P=0.04, respectively]. The number of missing teeth in pre-diabetic group [2.0 (7.0)] was significantly lower than that in glucose well controlled group [5.0 (9.0), P=0.02]. The percent of bleeding on probing [BOP(+)%] in pre-diabetic group [(63.89±20.03)%] was significantly higher than that in normal blood glucose group [(54.51±22.29)%, P=0.04] and glucose well controlled group [(53.12±21.77)%, P=0.03]. The prevalence of Pg in pre-diabetic group (81.5%) was significantly higher than that in glucose poor controlled group (54.2%, P=0.02). The prevalence of Tf in pre-diabetic group (96.3%) was significantly higher than that in glucose poor controlled group (76.4%, P=0.01). Meanwhile the quantity of Pg [1.58 (4.75)] and Tf [5.46 (7.77)] in pre-diabetic group were significantly higher than that in glucose poor controlled group [0.60 (1.87), P=0.01 and 1.63 (3.06), P<0.01, respectively]. The quantity of Pn [0.85 (1.68)] in pre-diabetic group was significantly higher than that in normal blood glucose group [0 (1.02), P=0.04].@*Conclusions@#Pre-diabetic patients showed severe periodontal infection and BOP(+)% than other three groups and had high risk-level of periodontitis.

The Relationship between the Bacterial Vaginosis and 8 Putative Periodontal Pathogen Infection / 昆明医科大学学报

Objective To investigate the relationship between the bacterial vaginosis and 8 putative periodontal pathogen infection.Methods A total of 48 patients with bacterial vaginosis were collected and 47 healthy female patients were selectedin the control group.Vaginal secretion and subgingival plaque were obtained from the study group and the control group.The presence of Porphyromonasgingivalis (P.g),Tannerella forsythia (T.f),Treponemas denticola (T.d),Prevotell intermedia (P.i),Prevotella nigrescen (P.n),Peptostreptococcus micros (P.m),Fusobacteriumnucleatum (F.n) and Campylobacterrectas (C.r) was detected by DNA extraction and PCR method.Simultaneously,all the patients underwent a clinical periodontal examination of the teeth in community periodontal index,including plaque index (PLI),bleeding on probing (BOP),probing depth (PD) and clinical attachment loss (CAL) Results The prevalence of periodontal disease,PLI,BOP and CAL in the study group was significantly higher than in the control group (P＜0.05) and the PD had no statistically significant difference between the 2 groups (P＞O.05).The 2 groups were both detected 8 putative periodontal pathogens in the vaginal secretion and the subgingival plaque samples.The detection ratio of T.dfrom both the vaginal secretion and subgingival plaque samples was significantly higher in the study group than that in the control group (P ＜0.05),and other 7 pathogens showed no statistically significant difference (P ＞0.05) Conclusion The prevalence of periodontal disease was higher among the bacterial vaginosis patients.The 8 putative periodontal pathogens were normal flora in the subgingival plaque and vaginal secretion.Td might be relevant to the pathogenesis of bacterial vaginosis.

Alzheimer's disease and periodontitis - an elusive link / A doença de Alzheimer e periodontite - um esquivo link

Alzheimer's disease is the preeminent cause and commonest form of dementia. It is clinically characterized by a progressive descent in the cognitive function, which commences with deterioration in memory. The exact etiology and pathophysiologic mechanism of Alzheimer's disease is still not fully understood. However it is hypothesized that, neuroinflammation plays a critical role in the pathogenesis of Alzheimer's disease. Alzheimer's disease is marked by salient inflammatory features, characterized by microglial activation and escalation in the levels of pro-inflammatory cytokines in the affected regions. Studies have suggested a probable role of systemic infection conducing to inflammatory status of the central nervous system. Periodontitis is common oral infection affiliated with gram negative, anaerobic bacteria, capable of orchestrating localized and systemic infections in the subject. Periodontitis is known to elicit a "low grade systemic inflammation" by release of pro-inflammatory cytokines into systemic circulation. This review elucidates the possible role of periodontitis in exacerbating Alzheimer's disease. Periodontitis may bear the potential to affect the onset and progression of Alzheimer's disease. Periodontitis shares the two important features of Alzheimer's disease namely oxidative damage and inflammation, which are exhibited in the brain pathology of Alzheimer's disease. Periodontitis can be treated and hence it is a modifiable risk factor for Alzheimer's disease.

A doença de Alzheimer é uma proeminente causa e a forma mais comum de demência. Caracteriza-se clinicamente por uma progressiva diminuição da função cognitiva, que tem início com a deterioração da memória. A exata etiologia e o mecanismo fisiopatológico da doença de Alzheimer ainda não são totalmente compreendidos. No entanto, postula-se que a neuroinflamação desempenhe um papel crucial na patogênese da doença de Alzheimer. A doença de Alzheimer é caracterizada por importantes características inflamatórias, assinalada pela ativação microglial e escalada dos níveis de citocinas pró-inflamatórias nas regiões afetadas. Estudos têm sugerido um provável papel de infecção sistêmica imbuída de estado inflamatório do sistema nervoso central. Periodontite é uma infecção oral comum associada a germes Gram-negativos, anaeróbios, capaz de orquestrar infecções localizadas e sistêmicas no paciente. É conhecida por suscitar um "baixo grau de inflamação sistêmica" pela liberação de citocinas pró-inflamatórias na circulação sistêmica. Esta revisão elucida o possível papel da periodontite no agravamento da doença de Alzheimer e pode ter o potencial de afetar o início e a progressão da doença de Alzheimer. Periodontite partilha as duas importantes características da doença de Alzheimer: dano oxidativo e inflamação, que estão presentes na patologia do cérebro com doença de Alzheimer. Periodontite pode ser tratada e, portanto, é um fator de risco modificável para a doença de Alzheimer.

Clinical and microbiologic effects of the subantimicrobial dose of doxycycline on the chronic periodontitis / 대한치주과학회지

PURPOSE: Tetracycline and its chemically modified non-antibacterial analogues can inhibit certain host-derived tissue destructive collagenases such as matrix metalloproteinases. The purpose of this study was to evaluate clinical and microbiologic effects of the subantimicrobial dose of doxycycline(SDD) in conjunction with scaling and root planing. MATERIALS AND METHODS: A total of 30 patients with chronic periodontitis who were going to receive scaling and root planing were randomly allocated to receive either a doxycycline hyclate for 3 months or nothing. Clinical probing depth, clinical attachment level, gingival recession, and bleeding on probing were measured by one periodontist. After a periodontal examination, microbial samples were collected using sterile paper points. The effect of SDD in conjunction with scaling and root planing on alterations of the periodontal pathogens (Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis) were also assessed using 16S rRNA polymerase chain reaction. RESULTS: During the treatment period, clinical parameters for both treatment group and control group were improved. After 3 months, reductions in probing depth and gains in clinical attachment level were significantly greater for the SDD group than control group. Microbial analysis showed that there was no alteration of the periodontal pathogens and no difference between the groups. CONCLUSION: This study suggested that the subantimicrobial dose of doxycycline as an adjunct therapy with scaling and root planing might be effective and safe in the management of chronic periodontitis.

Identification of putative periodontal pathogens in Korean chronic periodontitis patients / 대한치주과학회지

PURPOSE: Specific bacteria are believed to play an important role in chronic periodontitis. Although extensive microbial analyses have been performed from subgingival plaque samples of periodontitis patients, systemic analysis of subingival microbiota has not been carried out in a Korean population so far. The purpose of this study was to investigate the prevalence of 29 putative periodontal pathogens in Korean chronic periodontitis patients and evaluate which pathogens are more associated with Korean chronic periodontitis. MATERIAL AND METHODS: A total of 86 subgingival plaque samples were taken from 15 chronic periodontits(CP) patients and 13 periodontally healthy subjects in Korea. CP samples were obtained from the deepest periodontal pocket (>3 mm probing depth[PD]) and the most shallow periodontal probing site (< or =3 mm PD) in anterior tooth and posterior tooth, respectively, of each patient. Samples in healthy subjects were obtained from 1 anterior tooth and 1 posterior tooth. Polymerase chain reaction (PCR) of 16S ribosomal DNA (rDNA) of subgingival plaque bacteria was performed. Detection frequencies(% prevalence) of 29 putative periodontal pathogens were investigated as bacterium-positive sites/total sites RESULTS: With the exception of Olsenella profuse and Prevotella nigrescens, the sites of diseased patients generally showed higher prevalence than the healthy sites of healthy subjects for all bacteria analyzed. Tanerella forsythensis (B.forsythus), Campylobacter rectus, Filifactor alocis, Fusobacterium nucleatum, Porphyromonas endodontalis and Porphyromonas gingivalis were detected in more than 80% of sites with deep probing depths in CP patients. In comparison between the sites (deep or shallow PD) of CP patients and the healthy sites of healthy subjects, there was statistically significant difference(P <0.05) of prevalence in T.forsythensis (B.forsythus), C.rectus, Dialister invisus, F.alocis, P.gingivalis and Treponema denticola. CONCLUSION: Our results demonstrate that the four putative periodontal pathogens, T.forsythensis (B.forsythus), C.rectus, P.gingivalis and F.alocis are closely related with CP patients in the Korean population.

The inhibitory effect of lactic acid bacteria to periodontal pathogens / 대한치주과학회지

This study was performed to evaluate the effect of hydrogen peroxide-producing Lactobacillus acidophilus V-2Oonthe replication of periodontal pathogens, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. When A. actinomycetemcomitam and P. gingivalis were incubated alone and in the combination with L. acidophilus V-20, the viable cell numbers of A. actinomycetemcomitans and P. gingivalis were compared between those cultures. The effect of S. mutans, E. durans, and L. lactis on the replication of A. actinomycetemcomitans and P. gingivalis was also evaluated. The change of periodontal indexes(probine depth, gingival index, GCF volume) and the viable cell numbers of A. actinomycetemcomitans and black pigmented bdcteroides in subgingival plaque sample were evaluated following gargling of fermented milk made from L. acidophilus V-20 for 1 month on patients with periodontal disease in maintenance phase. In the mixed culture of L. acidophilus V-20 and A. actinomycetemcomitans or P. gingivalis, the replication of A. adinomycetemcomitam or P. gingivalis was completely inhibited. But in the mixed culture of P. gingivalis and hydrogen peroxide-nonproducing Lactobacillus casei, the viable cell numbers of P. gingivalis was not decreased when compared with the numbers in the mixed culture of P. gingivalis and L. acidophilus V-20. In the mixed culture of A. actinomycetemcomitam and S. mutans, E. durans, or L. lactis, the viable cell number of A. adinomycetemcomitans was not almost changed when compared with the numbers in the culture of A. actinomycetemcomitans alone. And in the mixed culture of P. gingivalis and E. durans or L. lactis, the viable cell numbers of P. gingivalis was not almost changed compared with the counts in the culture of P. gingivalis alone. But the replication of P. gingivalis was completely inhibited in the mixed culture of P. gingivalis and S. mutans. When the change of periodontal indexes following gargling of fermented milk was compared with baseline, probing depth and gingival index were not changed, but GCF volume was significantly dcreased(p (0.05). And when the viable cell numbers of microorganisms in subgingival plaque sample were compared with baseline, total viable cell number was almost unchanged and the viable cell numbers of A. actinomycetemcomitans and black pigmented bdcteroides were significantly decreased(p<0.05). These results suggest that L. acidophilus V-20 inhibit the replication of A. actinomycetemcomitans and black pigmented bacteroides by the formation of hydrogen peroxide.