Subgingival periodontal pathogens associated with chronic periodontitis in Yemenis

Dynamics of Gingival Indices and Microbiological Findings During Treatment of Plaque-Induced Gingivitis in Children Aged 10-14 Years

BACKGROUND

The study analyzed the dynamics of the clinical periodontal status during the treatment of adolescents with generalized plaque-induced gingivitis.

AIM

Assessment of the predominant subgingival microflora in the case of a diagnosed inflammatory process in the gingiva in childhood.

METHODS

Full-mouth periodontal assessment of plaque accumulation and bleeding on probing with an electronic periodontal probe was performed during the treatment of 34 adolescents with generalized plaque-induced gingivitis. The treatment protocol includes five visits (1, 3, 7, 14, and 30 days). Subgingival biofilm sampling was performed by real-time PCR testing to identify, follow-up in dynamics, and determine the quantities of main subgingival periodontopathogens during treatment. Three samples per child were taken from five teeth with the most severe inflammation.

RESULTS

For children aged 10-14 years with generalized plaque-induced gingivitis, two weeks after the start of treatment, the index values for bleeding on probing decreased twice from 53 to 27%. C. gingivalis was isolated before the start of treatment in all children, followed by P. intermedia, P. micros (70,4%) and T. denticola, T. forsythia (52,9%). Representatives of the red complex according to Socransky showing greater resistance to the therapy performed in terms of frequency and amount.

CONCLUSION

The predominant subgingival microflora in adolescents with generalized plaque-induced gingivitis is representative of the orange and red Socransky complex, with index values decreasing smoothly at each subsequent visit during treatment.

Collagenase-Responsive Hydrogel Loaded with GSK2606414 Nanoparticles for Periodontitis Treatment through Inhibiting Inflammation-Induced Expression of PERK of Periodontal Ligament Stem Cells

GSK2606414 is a new, effective, highly selective PERK inhibitor with adenosine-triphosphate-competitive characteristics. It can inhibit endoplasmic reticulum stress and has the possibility of treating periodontitis. However, owing to its strong hydrophobicity and side effects, highly efficient pharmaceutical formulations are urgently needed to improve the bioavailability and therapeutic efficacy of GSK2606414 in the treatment of periodontitis. Herein, a novel local GSK2606414 delivery system was developed by synthesizing GSK2606414 nanoparticles (NanoGSK) and further loading NanoGSK into a collagenase-responsive hydrogel. The drug release results showed that the drug-loaded hydrogels had outstanding enzymatic responsive drug release profiles under the local microenvironment of periodontitis. Furthermore, in vitro studies showed that the drug-loaded hydrogel exhibited good cellular uptake and did not affect the growth and proliferation of normal cells, while the drug-loaded hydrogel significantly improved the osteogenic differentiation of inflammatory cells. In the evaluations of periodontal tissue repair, the drug-loaded hydrogels showed a great effect on inflammation inhibition, as well as alveolar bone regeneration. Therefore, this work introduces a promising strategy for the clinical treatment of periodontitis.

Influence of Bariatric Surgery on Oral Microbiota: A Systematic Review

The study aims to systematically review the available literature to evaluate the changes in oral microbiota in patients after bariatric surgery (BS) and correlates these alterations in microorganisms with common oral manifestations. Relevant Electronic databases were systematically searched for indexed English literature. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed for framework designing, application, and reporting of the current systematic review. The focused PICO question was: "Is there any change in oral microbiota (O) of patients (P) who underwent BS (I) when compared with non-BS groups (C)?' Seven articles were selected for qualitative synthesis. On application of the National Institutes of Health (NIH) quality assessment tool, six studies were found to be of fair quality and one was of good quality. All the seven included studies evaluated the effect of BS on oral microbiota in humans. The outcomes of this review suggest that considerable changes take place in oral microbiota after BS which can be correlated with common oral manifestations. These changes are mainly due to the indirect effect of BS and may vary with the individuals. Due to variations in the included studies, it is difficult to proclaim any persistent pattern of oral microbiota found after BS.

Antimicrobial Efficacy of Blended Essential Oil and Chlorhexidine against Periodontal Pathogen (P.gingivalis)-An In Vitro Study

Background

Essential oils (EOs) have a considerable amount of therapeutic and preventive effect in treating dental diseases due to their wider potential as antibacterial and anti-inflammatory agents. EOs like virgin coconut oil, eucalyptus oil, peppermint oil thyme oil, and clove oil, when used in combination, may further have enhanced antimicrobial effects. However, limited information exists on the synergistic effect of these oils when used in combination, especially on the primary periodontal pathogen Porphyromonas gingivalis.

Aim

The current study aims to compare the antimicrobial efficacy of commercially available EO on the periodontal pathogen, P. gingivalis, in comparison to chlorhexidine (CHX).

Materials and Methods

Antimicrobial efficacy of EO and CHX was assessed at various concentrations against the periodontal pathogen P. gingivalis, by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).

Results

P. gingivalis was seen to be sensitive at a MIC of 100 μg/ml and 50 μg/ml concentration of the EO, which is regarded as the MIC of EO against P. gingivalis and CHX effectively inhibited microbial growth at 0.4 μg/ml.

Conclusion

A combination of EOs possesses a potent antibacterial activity against P. gingivalis, and the antibacterial efficacy increases with increasing concentration of EOs.

A randomized, placebo-controlled clinical trial evaluating of a mouthwash containing Sambucus williamsii var. coreana extract for prevention of gingivitits

The purpose of this study is to verify the clinical applicability by applying a mouthwash containing Sambucus williamsii var. coreana extract for preventing periodontal disease. A randomized, double-blind, placebo-controlled study was conducted on 64 patients, excluding those with insufficient data, who visited M dental clinic located in Busan, Korea. Thirty-two people were assigned respectively to the saline solution gargle group and the Sambucus williamsii var. coreana extract gargle group to conduct the O'Leary index, plaque index (PI), gingival index (GI), and subgingival plaques. For the homogeneity of the two groups, scaling was carried out one week before the experiment, and the participants were taught for oral care to conduct during the study period. SPSS 24.0 for Windows (IBM Corp., Armonk, NY, USA) was used to compare the saline solution gargle group and the Sambucus williamsii var. coreana extract gargle group as well as to analyze Baseline (before gargle application), Treatment (immediately after gargle application), and After 5 Days (5 days after gargle application). There was a significant difference in the O'Leary index, PI, GI and subgingival plaques after Treatment and After 5 days (p < 0.05). Also, the periodontal-related indexes improved as the application time increased in the Sambucus williamsii var. coreana extract gargle group. The antibacterial effect was also shown for gram-positive bacteria and gram-negative bacteria in subgingival plaques as the application time increased. The use of the mouthwash containing Sambucus williamsii var. coreana extract was found to be effective for oral periodontal-related indicators and bacteria causing periodontal disease. Therefore, using a mouthwash containing Sambucus williamsii var. coreana extract, a natural drug, will possibly maintain healthy periodontal health by inhibiting and preventing the progression of periodontal disease.

The effect of cranberry juice and a cranberry functional beverage on the growth and metabolic activity of selected oral bacteria

BACKGROUND

The oral microbiota is a significant risk indicator for oral diseases, such as dental caries and periodontal inflammation. Much attention is presently paid to the development of functional foods (e.g. beverages containing cranberry constituents, or foods containing probiotics) that may serve as adjuncts for oral disease treatments (e.g. periodontitis and caries). Cranberry fruit, due to its unique chemical composition and antimicrobial potential, is a possible ingredient of such foods. The study aimed to investigate the effects of cranberry juice (CJ) and a cranberry functional beverage (mixture of 80% v/v apple juice, 20% v/v cranberry juice, and 0.25 g/100 mL ground cinnamon; CFB) on the growth and metabolic activity of selected oral bacteria.

METHODS

Serial dilution pour plate method (SDPP) was used to examine the effect of CJ and CFB on the growth of Actinomyces naeslundii, Streptococcus mutans, and Lactobacillus paracasei subsp. paracasei. 48-h electrical impedance measurements (EIM) during the cultivation of A. naeslundii were applied to evaluate the utility of the method as a rapid alternative for the assessment of the antimicrobial potential of cranberry beverages.

RESULTS

The tested bacteria differed in their susceptibility to the antimicrobial action of CJ and CFB, with L. paracasei subsp. paracasei being least vulnerable to CFB (according to SDPP). Although CJ at a concentration of 0.5 mL/mL, showed a bactericidal effect on the growth of S. mutans, A. naeslundii was more sensitive to CJ (SDPP). Its inhibitory effect on A. naeslundii was seen even at concentrations as small as 0.03125-0.125 mL/mL (SDPP and EIM). On the other hand, S. mutans seemed to be more vulnerable to CFB than A. naeslundii (SDPP).

CONCLUSIONS

CFB may be considered an adjunct in the treatment of oral diseases due to its action against selected oral pathogens, and not against the presumably beneficial L. paracasei subsp. paracasei. Bioelectrical impedance measurements appear to be a quick alternative to evaluating the antimicrobial activity of fruit beverages, but their utility should be confirmed with tests on other bacteria.

Impact of Adjunctive Diode Laser Application to Non-Surgical Periodontal Therapy on Clinical, Microbiological and Immunological Outcomes in Management of Chronic Periodontitis: A Systematic Review of Human Randomized Controlled Clinical Trials

Background

Due to the limitations of scaling and root planing (SRP) in chronic periodontitis (CP) management, research has been focused on utilising additional therapies to enhance conventional treatment methods. The present systematic review is aimed to appraise the accessible scientific evidence of in vivo human studies to establish the effectiveness of adjunctive diode (λ 808- λ 980nm) laser treatment to SRP in CP.

Methodology

This systematic review was conducted following the PRISMA statement guidelines. The review protocol is registered in PROSPERO (CRD 42021227695). The search strategies were based on structured electronic and manual (with appropriate keywords) and were conducted to collect the applicable published data on RCTs studies (in vivo human), spanning over ten years between August 2010 and August 2020. The articles were selected to address the following research focus question: “Does diode laser (λ 808- λ 980nm) therapy have superior effects as an adjunct to SPR, compared to SRP alone, in terms of clinical or microbiological or immunological profiles in the management of CP?”

Results

Fifteen articles met the eligibility criteria and are included in this review. A wide range of discrepancies and inconsistencies were shown in the outcomes of the laser and SPR treatment modality, compared to SRP alone. The data on standardised study protocol, optimal laser parameters and outcome measurements were inconclusive, and a high risk of bias in the majority of the studies observed, which are crucial in establishing a homogenous and reproducible protocol.

Conclusion

In light of the confined evidence-based data and critical evaluation of this systematic review, the efficacy of adjunctive diode laser treatment ranging between 808 and 980nm to SRP remains debatable. The observational quality of the present systematic review was emphasised after scrutinising the available data, and an attempt to propose a laser protocol for future RCTs consideration was a great challenge due to an absence of clear and standardised recommendations in delivering a reliable laser protocol which can be replicable by future investigators. RCTs with robust methodology are warranted.

Subgingival microflora in adolescent females with polycystic ovary syndrome and its association with oral hygiene, gingivitis, and selected metabolic and hormonal parameters

OBJECTIVES

Research studies suggest that polycystic ovary syndrome (PCOS) may influence the composition of the oral microflora in women. This study aimed to investigate factors affecting the number of selected periopathogens in a young cohort of females with PCOS and to assess the association between oral hygiene, subgingival microbiome, gingival health, and metabolic and hormonal parameters.

MATERIALS AND METHODS

Thirty-two subjects with PCOS and twenty-three healthy controls aged 15-19 years were examined periodontally by a calibrated dentist. A real-time PCR method was used for the identification of 9 subgingival microorganisms. Subjects with PCOS underwent blood tests for determination of FSH, LH, total testosterone, DHEA-S, estradiol, SHBG, fasting glucose, fasting insulin, and lipid profile.

RESULTS

Gingival index (GI), the proportion of bleeding sites (BOP%), probing depth (PD), and plaque index (PLI) did not differ significantly between cases and healthy age-mates. The control group had significantly higher levels of Peptostreptococcus micros and substantially greater percentage of subjects infected by Treponema denticola. Capnocytophaga gingivalis count was positively correlated with the level of estradiol, while the concentration of HDL-C was negatively correlated with the number of Aggregatibacter actinomycetemcomitans and orange complex bacteria.

CONCLUSIONS

PCOS in young patients was not associated with higher pathogenicity of subgingival biofilms.

CLINICAL RELEVANCE

Further studies are needed to explain the relationship between hormonal and metabolic abnormalities, subgingival microflora, and periodontal health in patients with PCOS.

Prevalence of target anaerobes associated with chronic periodontitis

Introduction

Periodontal diseases are a group of chronic infections that destroy tissues surrounding and supporting the teeth. Data on the anaerobes associated with periodontal infections in Kuwait is lacking.

Aim

To investigate the target anaerobes associated with chronic periodontitis (CP) in patients admitted to Dental Clinics in Kuwait University Health Sciences Center, Kuwait.

Methodology

Patients with CP (severe and moderate) were recruited into this study during a period of 15 months. Samples were collected directly from inside the gingival pockets and subjected to semi-quantitative PCR assays.

Results

A total of 30 patients, stratified into moderate and severe CP and 31 healthy individuals, used as controls, were studied. Nine (30 %) of the 30 patients were in the 50–59-year age group. The detection rate of Aggregatibacter actinomycetemcomitans between the patients (9 : 30 %) versus the controls (5 : 16.1 %) was non-significant (P >0.05). Fusobacterium spp., were detected in all patients versus 29 (93.1 %) controls, (P >0.05). However, four target anaerobes were significantly associated with CP patients; Porphyromonas gingivalis was detected in ten (33.3 %) patients versus two (6.4 %) controls (P <0.0001); Tannerella forsythia 25 (83.3 %) versus 16 (51.6 %) controls (P <0.0001); Parvimonas micra 27 (90 %) versus 16 (51.6 %) controls (P <0.0001) and Treponema denticola, 18 (60 %) versus nine (29 %) controls (P <0.0001), respectively. Prevotella spp. were detected in 27 (90 %) patients and 30 (96.7 %) controls (P>0.5). There was no significant difference in the burden of Prevotella spp. between patients and controls determined by semi-quantitative PCR assays.

Conclusion

Some (4/7) of the target anaerobes were significantly associated with CP in our study. P. gingivalis was the most strongly associated anaerobe with CP, although not the keystone bacteria, while Prevotella spp. was similar to the healthy controls.

Antibiotic Resistance of Human Periodontal Pathogen Parvimonas micra Over 10 Years

Changes were evaluated over 10 years in the in vitro resistance of human periodontopathic strains of Parvimonas micra to four antibiotics. Subgingival biofilms culture positive for P. micra from 300 United States adults with severe periodontitis in 2006, and from a similar group of 300 patients in 2016, were plated onto anaerobically incubated enriched Brucella blood agar alone, or supplemented with either doxycycline (4 mg/L), clindamycin (4 mg/L), amoxicillin (8 mg/L), or metronidazole (16 mg/L). P. micra growth on antibiotic-supplemented media indicated in vitro resistance to the evaluated antibiotic concentration. P. micra resistance was significantly more frequent among patients in 2016, as compared to 2006, for doxycycline (11.3% vs. 0.3% patients; 37.7-fold increase), and clindamycin (47.3% vs. 2.0% patients; 23.7-fold increase) (both p < 0.001), whereas resistance to amoxicillin (2.3% vs. 1.0% patients) and metronidazole (0% vs. 0.3% patients) remained low and statistically unchanged between the two patient groups (p-values > 0.05). No P. micra isolates in 2006 or 2016 were jointly resistant in vitro to both amoxicillin and metronidazole. The alarming increases in subgingival P. micra resistance to doxycycline and clindamycin raise serious questions about the empiric use of these antibiotics, either locally or systemically, in the treatment of United States periodontitis patients harboring subgingival P. micra.

Exploring the putative interactions between chronic kidney disease and chronic periodontitis

Chronic kidney disease (CKD) and chronic periodontitis (CP) are both common diseases, which are found disproportionately comorbid with each other and have been reported to have a detrimental effect on the progression of each respective disease. They have an overlap in risk factors and both are a source of systemic inflammation along with a wide selection of immunological and non-specific effects that can affect the body over the lifespan of the conditions. Previous studies have investigated the directionality of the relationship between these two diseases; however, there is a lack of literature that has examined how these diseases may be interacting at the localized and systemic level. This review discusses how oral microorganisms have the ability to translocate and have distal effects and provides evidence for microbial involvement in a systemic disease. Furthermore, it summarizes the reported local and systemic effects of CKD and CP and discusses how the interaction of these effects may be responsible for directionality associations reported.

Microbiota Dysbiosis in Fungal Rhinosinusitis

Fungal rhinosinusitis is a unique phenotype of chronic rhinosinusitis with unique clinical and histological characteristics. The role of bacterial microbiota in various phenotypes chronic rhinosinusitis is not thoroughly understood. Therefore, we conducted 16s rRNA amplification sequencing to determine differences in bacterial communities between phenotypes (fungal vs. non- fungal) and anatomical sites (middle meatus vs. nasopharynx). Endoscope-guided swabs were used to collect samples from the middle meatus and nasopharynx of seven consecutive patients with fungal and 18 consecutive patients with non-fungal rhinosinusitis. DNA was extracted and investigated through 16S rRNA amplification. Among samples from the middle meatus, Shannon diversity was significantly lower in those from the fungal rhinosinusitis group (p = 0.029). However, no significant differences in diversity were noted between nasopharynx samples (p = 0.85). Fungal rhinosinusitis samples exhibited a distinct distribution of taxon relative abundance, which involved not only the absence of rhinosinusitis-associated commensal Corynebacterium and Fusobacterium in the middle meatus but also a significant increase in Haemophilus prevalence and abundance. This is the first study to compare bacterial communities in fungal and non-fungal rhinosinusitis samples. Our findings demonstrated that bacterial community dysbiosis was more apparent in fungal rhinosinusitis samples and was limited to the middle meatus.

Oral Microbiota Community Dynamics Associated With Oral Squamous Cell Carcinoma Staging

Oral squamous cell carcinoma (OSCC) is a highly aggressive cancer and the fourth leading malignancy among males in Taiwan. Some pathogenic bacteria are associated with periodontitis and oral cancer. However, the comprehensive profile of the oral microbiome during the cancer's progression from the early stage to the late stage is still unclear. We profiled the oral microbiota and identified bacteria biomarkers associated with OSCC. The microbiota of an oral rinse from 51 healthy individuals and 197 OSCC patients at different stages were investigated using 16S rRNA V3V4 amplicon sequencing, followed by bioinformatics and statistical analyses. The oral microbiota communities from stage 4 patients showed significantly higher complexity than those from healthy controls. The populations also dynamically changed with the cancer's progression from stage 1 to stage 4. The predominant phyla in the oral samples showed variation in the relative abundance of Fusobacteria, Bacteroidetes, and Actinobacteria. The abundance of Fusobacteria increased significantly with the progression of oral cancer from the healthy controls (2.98%) to OSCC stage 1 (4.35%) through stage 4 (7.92%). At the genus level, the abundance of Fusobacterium increased, while the number of Streptococcus, Haemophilus, Porphyromonas, and Actinomyces decreased with cancer progression. Fusobacterium periodonticum, Parvimonas micra, Streptococcus constellatus, Haemophilus influenza, and Filifactor alocis were associated with OSCC, and they progressively increased in abundance from stage 1 to stage 4. The abundances of Streptococcus mitis, Haemophilus parainfluenzae, and Porphyromonas pasteri were inversely associated with OSCC progression. We selected a bacterial marker panel of three bacteria (upregulated F. periodonticum, down-regulated S. mitis, and P. pasteri), which had an AUC of 0.956 (95% CI = 0.925-0.986) in discriminating OSCC stage 4 from the healthy controls. Furthermore, the functional prediction of oral bacterial communities showed that genes involved in carbohydrate-related metabolism, such as methane metabolism, and energy-metabolism-related parameters, such as oxidative phosphorylation and carbon fixation in photosynthetic organisms, were enriched in late-stage OSCC, while those responsible for amino acid metabolism, such as folate biosynthesis and valine, leucine, and isoleucine biosynthesis, were significantly associated with the healthy controls. In conclusion, our results provided evidence of oral bacteria community changes during oral cancer progression and suggested the possibility of using bacteria as OSCC diagnostic markers.

The Effects of Antimicrobial Peptide Nal-P-113 on Inhibiting Periodontal Pathogens and Improving Periodontal Status

Periodontal disease consists of chronic gingival inflammation characterized by both degradation of the periodontal connective tissue and alveolar bone loss. Drug therapy is used as an auxiliary treatment method in severe chronic periodontitis, aggressive periodontitis, and periodontitis-associated systemic disease. Nal-P-113, a modified antimicrobial peptide, specifically replaces the histidine residues of P-113 with the bulky amino acid β-naphthylalanine, and our previous studies have verified that this novel peptide is not toxic to the human body within a certain concentration range. The objective of the present study was to evaluate the effect of Nal-P-113 on periodontal pathogens and periodontal status in clinical studies. In a split-mouth clinical trial, the pocket depth and bleeding index values tended to decrease in the experimental group compared with those in the control group. SEM results verified that Nal-P-113 restrained the maturation of plaque. Based on real-time polymerase chain reaction, the levels of Fusobacterium nucleatum, Streptococcus gordonii, Treponema denticola, and Porphyromonas gingivalis in subgingival plaque were decreased when the subjects were given Nal-P-113. Bacterial growth curve analysis and a biofilm susceptibility assay verified that Nal-P-113 at a concentration of 20 μg/mL restrained the growth of S. gordonii, F. nucleatum, and P. gingivalis and biofilm formation. Therefore, Nal-P-113 effectively reduces periodontal pathogens and ameliorates periodontal status.

Validation of a multiplex qPCR assay for the identification and quantification of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis: In vitro and subgingival plaque samples

OBJECTIVE

To validate a multiplex qPCR (m-qPCR) assay for the simultaneous identification and quantification of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis in subgingival samples.

MATERIAL AND METHODS

In vitro samples: DNA combinations of A. actinomycetemcomitans and P. gingivalis in similar or different concentrations were prepared. qPCR and m-qPCR were performed using the same primers and hydrolysis probes specific for 16SrRNA genes. Results were analyzed using intra-class (ICCs) and Lin's correlation coefficients (r) based on quantification cycle (Cq) values. Subgingival plaque samples: a cross-sectional study analyzing subgingival plaque samples harvested from periodontally-healthy and chronic periodontitis patients. Samples were processed by either qPCR or m-qPCR targeting both bacteria. Sensitivity, specificity, predictive values and Lińs correlation coefficients (r) were calculated using CFU/mL as primary outcome.

RESULTS

In vitro samples: m-qPCR yielded a good reproducibility (coefficients of variation around 1% and ICCs > 0.99) for both bacterial species. m-qPCR achieved detection limits and specificity similar to qPCR. An excellent concordance (r = 0.99) was observed between m-qPCR and qPCR for A. actinomycetemcomitans and P. gingivalis without statistical significant differences between both methods Subgingival plaque samples: a high sensitivity (above 80%) and specificity (100%) was obtained with the m-qPCR for both bacteria. The m-qPCR yielded a good concordance in Cq values, showing a good level of agreement between qPCR and m-qPCR.

CONCLUSION

The tested m-qPCR method was successful in the simultaneous quantification of A. actinomycetemcomitans and P. gingivalis, with a high degree of sensitivity and specificity on subgingival plaque samples.

Quantification by qPCR of Pathobionts in Chronic Periodontitis: Development of Predictive Models of Disease Severity at Site-Specific Level

Currently, there is little evidence available on the development of predictive models for the diagnosis or prognosis of chronic periodontitis based on the qPCR quantification of subgingival pathobionts. Our objectives were to: (1) analyze and internally validate pathobiont-based models that could be used to distinguish different periodontal conditions at site-specific level within the same patient with chronic periodontitis; (2) develop nomograms derived from predictive models. Subgingival plaque samples were obtained from control and periodontal sites (probing pocket depth and clinical attachment loss <4 mm and >4 mm, respectively) from 40 patients with moderate-severe generalized chronic periodontitis. The samples were analyzed by qPCR using TaqMan probes and specific primers to determine the concentrations of Actinobacillus actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Parvimonas micra (Pm), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf), and Treponema denticola (Td). The pathobiont-based models were obtained using multivariate binary logistic regression. The best models were selected according to specified criteria. The discrimination was assessed using receiver operating characteristic curves and numerous classification measures were thus obtained. The nomograms were built based on the best predictive models. Eight bacterial cluster-based models showed an area under the curve (AUC) ≥0.760 and a sensitivity and specificity ≥75.0%. The PiTfFn cluster showed an AUC of 0.773 (sensitivity and specificity = 75.0%). When Pm and AaPm were incorporated in the TdPiTfFn cluster, we detected the two best predictive models with an AUC of 0.788 and 0.789, respectively (sensitivity and specificity = 77.5%). The TdPiTfAa cluster had an AUC of 0.785 (sensitivity and specificity = 75.0%). When Pm was incorporated in this cluster, a new predictive model appeared with better AUC and specificity values (0.787 and 80.0%, respectively). Distinct clusters formed by species with different etiopathogenic role (belonging to different Socransky’s complexes) had a good predictive accuracy for distinguishing a site with periodontal destruction in a periodontal patient. The predictive clusters with the lowest number of bacteria were PiTfFn and TdPiTfAa, while TdPiTfAaFnPm had the highest number. In all the developed nomograms, high concentrations of these clusters were associated with an increased probability of having a periodontal site in a patient with chronic periodontitis.

Quantitative Molecular Detection of 19 Major Pathogens in the Interdental Biofilm of Periodontally Healthy Young Adults

In oral health, the interdental spaces are a real ecological niche for which the body has few or no alternative defenses and where the traditional daily methods for control by disrupting biofilm are not adequate. The interdental spaces are the source of many hypotheses regarding their potential associations with and/or causes of cardiovascular disease, diabetes, chronic kidney disease, degenerative disease, and depression. This PCR study is the first to describe the interdental microbiota in healthy adults aged 18–35 years-old with reference to the Socransky complexes. The complexes tended to reflect microbial succession events in developing dental biofilms. Early colonizers included members of the yellow, green, and purple complexes. The orange complex bacteria generally appear after the early colonizers and include many putative periodontal pathogens, such as Fusobacterium nucleatum. The red complex (Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) was considered the climax community and is on the list of putative periodontal pathogens. The 19 major periodontal pathogens tested were expressed at various levels. F. nucleatum was the most abundant species, and the least abundant were Actinomyces viscosus, P. gingivalis, and Aggregatibacter actinomycetemcomitans. The genome counts for Eikenella corrodens, Campylobacter concisus, Campylobacter rectus, T. denticola, and Tannerella forsythensis increased significantly with subject age. The study highlights the observation that bacteria from the yellow complex (Streptococcus spp., S. mitis), the green complex (E. corrodens, Campylobacter gracilis, Capnocytophaga ochracea, Capnocytophaga sputigena, A. actinomycetemcomitans), the purple complex (Veillonella parvula, Actinomyces odontolyticus) and the blue complex (A. viscosus) are correlated. Concerning the orange complex, F. nucleatum is the most abundant species in interdental biofilm. The red complex, which is recognized as the most important pathogen in adult periodontal disease, represents 8.08% of the 19 bacteria analyzed. P. gingivalis was detected in 19% of healthy subjects and represents 0.02% of the interdental biofilm. T. forsythensis and T. denticola (0.02 and 0.04% of the interdental biofilm) were detected in 93 and 49% of healthy subjects, respectively. The effective presence of periodontal pathogens is a strong indicator of the need to develop new methods for disrupting interdental biofilm in daily oral hygiene.

Quantitative analysis of classical and new putative periodontal pathogens in subgingival biofilm: a case-control study

BACKGROUND AND OBJECTIVES

A number of species/phylotypes have been newly implicated as putative periopathogens. The objective of this study was to explore associations among classical and new pathogens in subgingival biofilm and to assess their relative importance to chronic periodontitis.

MATERIAL AND METHODS

Pooled subgingival biofilm samples were obtained from 40 patients with chronic periodontitis and 40 healthy controls. Taqman q-PCR assays were used to determine the absolute and relative counts of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Parvimonas micra, Filifactor alocis, oral Synergistetes and oral TM7s. Microbial associations were assessed using cluster analysis. Different statistical models were used to explore associations between microbial parameters and periodontitis.

RESULTS

The median log and relative counts were lowest for TM7s (4.4 and 0.0016%, respectively) and highest for oral Synergistetes (7.2 and 1.4%, respectively). Oral Synergistetes clustered strongly with the red complex, particularly T. forsythia (100% rescaled similarity). All species/phylotypes except TM7s were significantly associated with periodontitis (Mann-Whitney test; p ≤ 0.005). However, P. gingivalis and F. alocis lost association after adjusting for confounders (ordinal regression). In receiving operator characteristic curve analysis, the log counts of oral Synergistetes were the best markers of periodontitis (82.5% sensitivity and specificity), followed by those of T. forsythia, P. micra and T. denticola. In prediction analysis, however, P. micra was the only microbial predictor of periodontal parameters.

CONCLUSIONS

Oral Synergistetes are presented here as new members of the red complex, with relative importance to periodontitis exceeding that of the classical members. P. micra is shown as an important periodontal pathogen warranting more attention.