Java project on periodontal diseases. The natural development of periodontitis: risk factors, risk predictors and risk determinants

The promise and challenges of genomics-informed periodontal disease diagnoses

Recent advances in human genomics and the advent of molecular medicine have catapulted our ability to characterize human and health and disease. Scientists and healthcare practitioners can now leverage information on genetic variation and gene expression at the tissue or even individual cell level, and an enormous potential exists to refine diagnostic categories, assess risk in unaffected individuals, and optimize disease management among those affected. This review investigates the progress made in the domains of molecular medicine and genomics as they relate to periodontology. The review summarizes the current evidence of association between genomics and periodontal diseases, including the current state of knowledge that approximately a third of the population variance of periodontitis may be attributable to genetic variation and the management of several monogenic forms of the disease can be augmented by knowledge of the underlying genetic cause. Finally, the paper discusses the potential utility of polygenic risk scores and genetic testing for periodontitis diagnosis now and in the future, in light of applications that currently exist in other areas of medicine and healthcare.

Study of various therapeutic strategies for the treatment of rapidly progressive periodontitis in experimental models

Rapidly progressive periodontitis is a serious disease that leads to rapid degradation of periodontal tissues and can lead to tooth loss at a relatively young age. The purpose of this article is to study the effectiveness of various modern methods in the treatment of this disease on an experimental model. A model of the studied pathology was created - a rat with a destroyed circular ligament of the tooth and a ligature applied to the base of the teeth. 5 study groups were formed, where various treatment methods were used: the appointment of soft food, the combination of intramuscular administration of vitamin C and prednisolone, the combination of tocilizumab and dexamethasone, and the combination of photodynamic therapy and tocilizumab. Histological material was taken from experimental animals and evaluated. The best results were noted in the group of photodynamic therapy and tocilizumab, where there was a better histological picture with minimal signs of the inflammatory process and satisfactory indicators of clinical dynamics, this approach showed high efficiency in resolving inflammation in the area of the affected foci. The 2nd place was taken by the combination of tocilizumab and dexamethasone, in this group, accelerated positive dynamics were noted compared to other groups, but the results of histological examination were worse than in group 1. In 3rd place - the combination of ascorbic acid with dexamethasone and the appointment of soft food, where there were almost no differences in terms of histological results and clinical picture compared to the control group. The combination of tocilizumab with photodynamic therapy is promising in the treatment of patients with rapidly progressive periodontitis, but additional human studies are required to include this type of treatment in clinical guidelines.

Factors Associated with the Extent of Clinical Attachment Loss in Periodontitis: A Multicenter Cross-Sectional Study

Periodontitis has significant public health implications, affecting individuals' overall health, well-being, and quality of life. This study aimed to assess the risk factors associated with the extent of clinical attachment loss (CAL) in a population diagnosed with periodontitis. Six hundred and sixty-seven patients with different degrees of CAL (mild, n = 223; moderate, n = 256; and advanced, n = 188) were enrolled. Socio-demographics, lifestyle, microbiological profiles, specific immune response, obesity, and single-nucleotide polymorphism of the IL1 gene were determined. Unconditional logistic regression models were conducted to determine the factors associated with the extent of CAL. Aging, smoking, microbial factors, plaque index, and IgG2 antibodies against Aggregatibacter actinomycetemcomitans were associated with advanced CAL. IgG2 antibodies against A. actinomycetemcomitans (OR 1.50; CI 95% 1.23-1.81), plaque accumulation (OR 2.69; CI 95% 2.20-3.29), Porphyromonas gingivalis (OR 1.93; CI 95% 1.35-2.76), Tanerella forsythia (OR 1.88; CI 95%1.30-2.70), and current smoking (OR 1.94; CI 95% 1.31-2.87) were associated with advanced CAL. Gene IL polymorphisms, obesity, and stress were not associated with the extent of CAL. Aging, plaque accumulation, smoking, and having antibodies against A. actinomycetemcomitans were the most critical factors associated with advanced CAL. In contrast, obesity, stress, and gene polymorphisms were not associated with the extent of CAL.

Aggregatibacter actinomycetemcomitans and Filifactor alocis as Associated with Periodontal Attachment Loss in a Cohort of Ghanaian Adolescents

The aims of the present study were to document the presence of Aggregatibacter actinomyctemcomitans and the emerging oral pathogen Filifactor alocis, as well as to identify genotypes of these bacterial species with enhanced virulence. In addition, these data were analyzed in relation to periodontal pocket depth (PPD) and the progression of PPD from the sampled periodontal sites during a two-year period. Subgingival plaque samples were collected from 172 periodontal pockets of 68 Ghanaian adolescents. PPD at sampling varied from 3-14 mm and the progression from baseline, i.e., two years earlier up to 8 mm. The levels of A. actinomycetemcomitans and F. alocis were determined with quantitative PCR. The highly leukotoxic JP2-genotype of A. actinomycetemcomitans and the ftxA a gene of F. alocis, encoding a putative Repeats-in-Toxin (RTX) protein, were detected with conventional PCR. The prevalence of A. actinomycetemcomitans was 57%, and 14% of the samples contained the JP2 genotype. F. alocis was detected in 92% of the samples and the ftxA gene in 52%. The levels of these bacterial species were significantly associated with enhanced PPD and progression, with a more pronounced impact in sites positive for the JP2 genotype or the ftxA gene. Taken together, the results indicate that the presence of both A. actinomycetemcomitans and F. alocis with their RTX proteins are linked to increased PPD and progression of disease.

Periodontal disease progression and gene polymorphisms: results after 3 years of active periodontal treatment

BACKGROUND

Although non-surgical periodontal treatment is considered the gold standard, a subgroup of patients displays recurrence/progression of periodontitis after treatment. The aim of the present prospective study was to assess the effect of IL-6 -572 G/C and IL-10 -592 C/A gene polymorphisms on the risk of disease recurrence/progression at 3 years following non-surgical periodontal treatment.

METHODS

Thirty-seven patients diagnosed with chronic periodontitis received oral hygiene instructions and non-surgical periodontal treatment and were monitored for 3 years. All individuals were clinically evaluated for PPD, CAL and BOP at baseline and 3 years. Based on the clinical findings at 3 years, all subjects were considered either "at risk" or "not at risk" of periodontal disease progression based on specific criteria. Blood samples were collected at baseline and genotyping of the polymorphisms in IL-6 (rs1800796) and IL-10 (rs1800872) genes were performed by PCR.

RESULTS

Following DNA separation and genotyping, 70.3% of the patients were homozygous carriers of the IL-6 -572G and 45.9% were carriers of the IL-10 -592A allele. Individuals at risk of disease progression ranged from 16.2% to 56.8% based on the criteria used. IL-6 -572 G/C and IL-10 -592 C/A polymorphisms were not associated with an increased risk of further disease progression (P>0.05) when the three criteria were examined. All examined periodontal clinical measures were significantly improved (P<0.05) after treatment. Males showed a significantly higher risk of disease progression than females when full-mouth BOP ≥30% was considered (P=0.008).

CONCLUSIONS

Within the limitations of this 3-year prospective study, individuals susceptible to periodontal disease as determined by the presence of the IL-6 -572GG genotype or the IL-10 -592A allele were not associated with an increased risk of further disease progression and the potential need for further treatment following non-surgical periodontal treatment. Males were more prone to be at risk of disease progression than females.

Risk of Peripheral Arterial Occlusive Disease with Periodontitis and Dental Scaling: A Nationwide Population-Based Cohort Study

Periodontitis (PD) is a common oral disease associated with various other diseases, particularly those affecting the cardiovascular system. This study explored whether peripheral artery occlusive disease (PAOD) is associated with PD and dental scaling. This study was a retrospective cohort study design from 2000 to 2018. The study population was newly diagnosed with periodontitis. The comparison group was defined as never diagnosed with periodontitis. The outcome variable was defined with the diagnosis of peripheral arterial occlusive disease (PAOD). The propensity score matching was performed by age, sex, comorbidities, and dental scaling between the two groups. Kaplan-Meier analysis was used to calculate the cumulative incidence of PAOD among the two groups. To perform the independent risk of the PAOD group, the multivariate Cox proportional hazard model was used to estimate the hazard ratios. First, 792,681 patients with PD and 458,521 patients with no history of PD were selected from Taiwan's Longitudinal Health Insurance Database, which comprises the data of two million beneficiaries. After propensity score matching between the PD and non-PD groups for age, sex, comorbidities, and dental scaling, 357,106 patients in each group were analyzed for PAOD risk. The incidence density, relative risk, and cumulative incidence of PAOD were higher in the PD group than in the non-PD group. After adjusting for all variables, the risk of PAOD for the PD group was greater than for the non-PD group (adjusted hazard ratio = 1.03; 95% CI, 1.01-1.06). Undergoing at least one dental scaling procedure reduced the risk of PAOD. Age over 65 years was also a risk factor. In conclusion, patients with PD have an increased risk of PAOD. In addition, our results can lead to increased attention to oral hygiene, as dental scaling has a trend towards a lower risk of PAOD.

Aggregatibacter actinomycetemcomitans and Filifactor alocis: Two exotoxin-producing oral pathogens

Periodontitis is a dysbiotic disease caused by the interplay between the microbial ecosystem present in the disease with the dysregulated host immune response. The disease-associated microbial community is formed by the presence of established oral pathogens like Aggregatibacter actinomycetemcomitans as well as by newly dominant species like Filifactor alocis. These two oral pathogens prevail and grow within the periodontal pocket which highlights their ability to evade the host immune response. This review focuses on the virulence factors and potential pathogenicity of both oral pathogens in periodontitis, accentuating the recent description of F. alocis virulence factors, including the presence of an exotoxin, and comparing them with the defined factors associated with A. actinomycetemcomitans. In the disease setting, possible synergistic and/or mutualistic interactions among both oral pathogens might contribute to disease progression.

Human Umbilical Cord Mesenchymal Stem Cells: Current Literature and Role in Periodontal Regeneration

Periodontal disease can cause irreversible damage to tooth-supporting tissues such as the root cementum, periodontal ligament, and alveolar bone, eventually leading to tooth loss. While standard periodontal treatments are usually helpful in reducing disease progression, they cannot repair or replace lost periodontal tissue. Periodontal regeneration has been demonstrated to be beneficial in treating intraosseous and furcation defects to varied degrees. Cell-based treatment for periodontal regeneration will become more efficient and predictable as tissue engineering and progenitor cell biology advance, surpassing the limitations of present therapeutic techniques. Stem cells are undifferentiated cells with the ability to self-renew and differentiate into several cell types when stimulated. Mesenchymal stem cells (MSCs) have been tested for periodontal regeneration in vitro and in humans, with promising results. Human umbilical cord mesenchymal stem cells (UC-MSCs) possess a great regenerative and therapeutic potential. Their added benefits comprise ease of collection, endless source of stem cells, less immunorejection, and affordability. Further, their collection does not include the concerns associated with human embryonic stem cells. The purpose of this review is to address the most recent findings about periodontal regenerative mechanisms, different stem cells accessible for periodontal regeneration, and UC-MSCs and their involvement in periodontal regeneration.

Aggregatibacter actinomycetemcomitans Outer Membrane Proteins 29 and 29 Paralogue Induce Evasion of Immune Response

Aggregatibacter actinomycetemcomitans (Aa) is abundant within the microbial dysbiotic community of some patients with periodontitis. Aa outer membrane protein 29 (OMP29), a member of the OMPA family, mediates the invasion of Aa to gingival epithelial cells (GECs). This study evaluated the effect of OMP29 and its paralogue OMP29^par on the response of GECs to Aa. The omp29 or/and omp29^par deletion mutants AaΔ29, AaΔ29P, and AaΔ29Δ29P were constructed, and recombinant Aa OMP29^His was obtained. Microarray analysis and the evaluation of cxcl-8 gene expression were performed to examine the response of GECs line OBA-09 to Aa and its mutants. The expression of cxcl-8 and its product CXCL-8 was examined in LPS-stimulated OBA-09 cells with Aa OMP29^His. Proteomics analysis showed that the deletion of omp29 led to overexpression of both OMP29^par and another membrane protein OMP39, the expression of which was further increased in AaΔ29Δ29P. OBA-09 cells challenged with AaΔ29Δ29P exhibited a higher expression of cxcl-8 in comparison to wildtype Aa strain AaD7S or single-deletion mutants AaΔ29 or AaΔ29P. LPS-stimulated OBA-09 cells challenged with Aa OMP29^His showed reduced expressions of cxcl-8 and its product CXCL-8. OBA-09 cells challenged with AaΔ29Δ29P in comparison to Aa strain AaD7S resulted in higher expressions of genes involved in apoptosis and inflammatory response such as bcl2, birc3, casp3, c3, ep300, fas, fosb, grb2, il-1α, il-1β, il-6, cxcl-8, nr3c1, prkcq, socs3, and tnfrsf1β and reduced expressions of cd74, crp, faslg, tlr1, and vcam1. The results suggested a novel strategy of Aa, mediated by OMP29 and OMP29^par, to evade host immune response by inhibiting CXCL-8 expression and modulating the genes involved in apoptosis and inflammatory response in GECs. Pending further confirmation, the strategy might interfere with the recruitment of neutrophils and dampen the host inflammatory response, leading to a more permissive subgingival niche for bacterial growth.

Periodontal disease prevalence, extent, and risk associations in untreated individuals

Objectives

to examine the prevalence, extent, and risk associations of untreated periodontitis.

Materials and Methods

A purposive sample of subjects who were never treated for periodontal conditions was clinically examined after collecting information about their sociodemographic characteristics, medical conditions, oral health behaviors, perceived stress, and perceived social support.

Results

A total of 431 subjects were recruited (response rate, 97.0%), and their mean age (SD) was 35.4 (13.3) years. Overall, high plaque levels were observed in all untreated individuals. The prevalence of periodontitis and severe (stage III/IV) periodontitis using the American Academy of Periodontology and European Federation of Periodontology (AAP/EFP) classification were 85.4% and 48.5%, respectively. The prevalence of moderate‐severe and severe periodontitis using the definitions of the Centers for Disease Control and Prevention (CDC) and AAP were 78.4% and 31.1%, respectively. The extent of periodontitis expressed as mean% of clinical attachment loss (CAL) ≥ 3 mm and CAL ≥ 5 mm were 34.9% and 14.4%, respectively, while the mean% of a periodontal probing depth (PPD) ≥4 mm and PPD ≥6 mm were 22.0% and 9.2%, respectively. Risk determinants associated with AAP/EFP periodontitis after the adjustment for other variables were age ≥35 years (odds ratio [OR] = 11.5) and lower income (OR = 2.5). Adjusted risk associations with stage II/IV periodontitis included age ≥35 years (OR = 8.2), males (OR = 2.5), lower income (OR = 2.3), and lower perceived stress (OR = 2.0). Adjusted risk associations with CDC/AAP moderate‐severe periodontitis included age ≥35 years (OR = 12.0), lower income (OR = 2.1), and current cigarette smoking (OR = 4.2). Adjusted risk associations with CDC/AAP severe periodontitis included age ≥35 years (OR = 4.5), males (OR = 1.9), lower education (OR = 2.0), lower income (OR = 1.7), uncontrolled diabetes mellitus (OR = 2.0), and current cigarette smoking (OR = 2.3).

Conclusions

The prevalence and extent of periodontitis were high in untreated subjects. Risk associations with untreated periodontitis included age ≥35 years, males, lower income, lower education, current cigarette smoking, uncontrolled diabetes mellitus, and lower perceived stress.

The Antimicrobial Susceptibility of Porphyromonas gingivalis: Genetic Repertoire, Global Phenotype, and Review of the Literature

The in vitro antimicrobial susceptibility of 29 strains of the major periodontal pathogen Porphyromonas gingivalis and three P. gulae (as an ancestor) to nine antibiotics (amoxicillin, amoxicillin/clavulanate, clindamycin, metronidazole, moxifloxacin, doxycycline, azithromycin, imipenem, and cefoxitin) was evaluated by E-testing of minimal inhibitory concentration (MIC) according to international standards. The results were compared with 16 international studies reporting MICs from 1993 until recently. In addition, 77 currently available P. gingivalis genomes were screened for antimicrobial resistance genes. E-testing revealed a 100% sensitivity of P. gingivalis and P. gulae to all antibiotics. This was independent of the isolation year (1970 until 2021) or region, including rural areas in Indonesia and Africa. Regarding studies worldwide (675 strains), several method varieties regarding medium, McFarland inoculation standards (0.5-2) and incubation time (48-168 h) were used for MIC-testing. Overall, no resistances have been reported for amoxicillin + clavulanate, cefoxitin, and imipenem. Few strains showed intermediate susceptibility or resistance to amoxicillin and metronidazole, with the latter needing both confirmation and attention. The only antibiotics which might fail in the treatment of P. gingivalis-associated mixed anaerobic infections are clindamycin, macrolides, and tetracyclines, corresponding to the resistance genes erm(B), erm(F), and tet(Q) detected in our study here, as well as fluoroquinolones. Periodical antibiotic susceptibility testing is necessary to determine the efficacy of antimicrobial agents and to optimize antibiotic stewardship.

Tooth loss and radiographic bone loss in patients without regular supportive care: A retrospective study

BACKGROUND

Very few studies have investigated the effect of patient and site factors on periodontal progression and long-term tooth loss in populations with minimal dental care. The aim of this retrospective study was to assess tooth loss and radiographic bone loss over at least 5 years in patients attending a national-health service primary care practice in Sicily and undergoing no regular care.

METHODS

Records of two hundred consecutive patients with at least 5 years follow-up were screened and demographic, clinical and radiographic data were retrieved. Analyses of associations between patient and site factors and tooth loss were performed.

RESULTS

After excluding not suitable patients, a total of 159 patient records with clinical and radiographic data with average 8.6 years follow-up were included. One hundred of these patients had no professional mechanical plaque removal (PMPR) carried out throughout the study follow-up. Nearly 65% of patients lost at least 1 tooth during the follow-up period, with a total of 400 extracted teeth (for periodontal and non-periodontal reasons). The annual tooth loss rate was slightly higher for "no PMPR" (untreated) patients (0.30 teeth/patient/year) compared with patients who had PMPR (0.27 teeth/patient/year). On a patient-level, only reduced frequency of daily tooth brushing was associated with tooth loss at logistic regression, whereas staging, grading and diagnosis of caries were associated with rates of tooth loss/year. At multilevel analysis including patient- and tooth-factors, age, diagnosis of caries and endodontic disease and percentage of bone loss at baseline were associated with tooth loss.

CONCLUSION

This study confirms the importance of tooth brushing, initial bone loss, caries and endodontic disease in predicting tooth survival in a primary care setting.

The Chairside Periodontal Diagnostic Toolkit: Past, Present, and Future

Periodontal diseases comprise a group of globally prevalent, chronic oral inflammatory conditions caused by microbial dysbiosis and the host immune response. These diseases specifically affect the tooth-supporting tissues (i.e., the periodontium) but are also known to contribute to systemic inflammation. If left untreated, periodontal diseases can ultimately progress to tooth loss, lead to compromised oral function, and negatively impact the overall quality of life. Therefore, it is important for the clinician to accurately diagnose these diseases both early and accurately chairside. Currently, the staging and grading of periodontal diseases are based on recording medical and dental histories, thorough oral examination, and multiple clinical and radiographic analyses of the periodontium. There have been numerous attempts to improve, automate, and digitize the collection of this information with varied success. Recent studies focused on the subgingival microbiome and the host immune response suggest there is an untapped potential for non-invasive oral sampling to assist clinicians in the chairside diagnosis and, potentially, prognosis. Here, we review the available toolkit available for diagnosing periodontal diseases, discuss commercially available options, and highlight the need for collaborative research initiatives and state-of-the-art technology development across disciplines to overcome the challenges of rapid periodontal disease diagnosis.

A questionnaire-based crossover study on the association of microbiological testing with prescription of systemic antibiotics following initial periodontal therapy

AIM

(1) To assess prescription of systemic antibiotics following initial periodontal therapy with and without the availability of microbiological information; (2) To identify factors associated with prescription of systemic antibiotics following initial periodontal therapy.

MATERIALS AND METHODS

Twenty-four clinicians were invited to complete a questionnaire on 20 patient records with respect to periodontal treatment planning, once with microbiological information available and once without. Randomization determined when the microbiological information was provided, and a 3-month washout period was respected between scoring sessions. Regression analysis was performed to identify factors associated with prescription of systemic antibiotics.

RESULTS

Twenty-one clinicians completed both scoring sessions. Clinicians prescribed systemic antibiotics in on average 56% (95% Confidence Interval (CI) [0.51; 0.61]) of the cases having microbiological information, and in 52% (95% CI [0.47; 0.57]) of the same cases not having that information (p = 0.094). The odds for prescribing systemic antibiotics were 3.34 (95% CI [2.06; 5.42]) times higher when the clinician had at least 3 years of experience, 2.55 (95% CI [1.40; 4.66]) times higher for patients diagnosed with periodontitis stage IV when compared to stage III, 1.08 (95% CI [1.04; 1.11]) times higher for younger patients, 2.78 times (95% CI [1.37; 5.56]) times higher for non-smokers and 2.22 (95% CI [1.27; 3.85]) times higher when less than three teeth would require extraction. No significant associations with the prescription of systemic antibiotics were found for detection of A.actinomycetemcomitans (p = 0.287), grade of periodontitis (p = 0.499) and gender of the patient (p = 0.067).

CONCLUSIONS

Based on a limited number of cases and clinicians, several patient and clinician related factors were associated with prescription of systemic antibiotics following initial periodontal therapy. However, microbiological testing was not.

A controlled study on the diagnostic accuracy of panoramic and peri-apical radiography for detecting furcation involvement

BACKGROUND

The aims of this study were (1) to determine the accuracy, sensitivity, and specificity of panoramic and peri-apical radiographs in diagnosing furcation involvement, as well as (2) to evaluate the possible impact of clinical experience on these diagnostic parameters.

METHODS

An existing radiographic dataset of periodontitis patients requiring implant surgery was retrospectively examined for furcation involvement. Criteria for inclusion were the presence of a CBCT, panoramic and peri-apical radiograph of the site of interest within a one-year time frame. All furcation sites were classified using the CBCT, which was considered as the gold standard, according to Hamp's index (1975). Ten experienced examiners and 10 trainees were asked to assess furcation involvement for the same defects using only the corresponding panoramic and peri-apical radiographs. Absolute agreement, Cohen's weighted kappa, sensitivity, specificity and ROC-curves were analyzed.

RESULTS

The study sample included 60 furcation sites in 29 multi-rooted teeth from 17 patients. On average, 20/60 furcations were correctly classified according to the panoramic radiographs, corresponding to a weighted kappa score of 0.209, indicating slight agreement. Similarly, an average of 19/60 furcations were correctly classified according to the peri-apical radiographs, corresponding to a weighted kappa score of 0.211, also indicating slight agreement. No significant difference between panoramic and peri-apical radiography was found (P = 0.903). When recategorizing FI Grades into 'no to limited FI' (FI Grade 0 and I) and 'advanced FI' (FI Grade II and III), the panoramic and peri-apical radiography showed low sensitivity (0.558 and 0.441, respectively), yet high specificity (0.791 and 0.790, respectively) for identifying advanced FI. The ROC-curves for the panoramic and peri-apical radiographs were 0.79 and 0.69 respectively. No significant difference was found between experienced periodontists and trainees (P = 0.257 versus P = 0.880).

CONCLUSION

Panoramic and peri-apical radiography are relevant tools in the diagnosis of FI and provide high specificity. Ideally, they are best used in combination with furcation probing, which shows high sensitivity. Furthermore, clinical experience does not seem to improve the accuracy of a radiological diagnosis of furcation sites.

TRIAL REGISTRATION

Patient radiographic datasets were retrospectively analyzed.

Comparative Analysis of the Temporomandibular Joints in Patients with Chronic Periodontitis Using Cone-Beam Computed Tomography (CBCT)

INTRODUCTION

Chronic periodontitis is a common disorder in adults causing periodontal destruction and loss of teeth. These clinical presentations may lead to temporomandibular joint disorders (TMDs). This study aimed to examine the anatomic structures of the temporomandibular joints (TMJs) using cone-beam computed tomography (CBCT) in patients with chronic periodontitis.

METHODS

Fifty patients with chronic periodontitis were enrolled in the study. Based on the severity of chronic periodontitis, these patients were divided into the mild, moderate, and severe groups. CBCT images of TMJs were acquired and reconstructed. Several indices on the reconstructed CBCT images were collected and analyzed, such as the oblique joint space parallel to the long axis of the condyle, the long axis diameter of the condyle, the vertical angle of the condyle, the inclination of the articular eminence vertical to the long axis of condyle at the oblique and sagittal positions, the depth of the fossa, and the horizontal angle of the cross-sections. The measurements between right and left sides of each patient were compared. Statistical analysis (paired samples t test) was performed.

RESULTS

The differences of the joint space vertical to the bilateral condyles were statistically significant (P < 0.05). Additionally, in the severe periodontitis group, the distances between the inner and outer poles of the condyles were statistically different (P < 0.05).

CONCLUSION

In patients with chronic periodontitis, TMJ space vertical to the condyles and the distances between the outer and inner poles of the condyle may change over time. These two indices can potentially be used as indicators for diagnosis and further comparative analyses.

In vitro anti‑bacterial activity of diosgenin on Porphyromonas gingivalis and Prevotella intermedia

Diosgenin (Dios), a natural steroidal sapogenin, is a bioactive compound extracted from dietary fenugreek seeds. It has a wide range of applications, exhibiting anti-oxidant, anti-inflammatory and anti-cancer activities. However, whether the extracts have beneficial effects on periodontal pathogens has so far remained elusive. The aim of the present study was to investigate the anti-bacterial effects of Dios on Porphyromonas gingivalis (P. gingivalis) and Prevotella intermedia (P. intermedia) in vitro. The anti-microbial effect of Dios on P. gingivalis and P. intermedia was assessed by a direct contact test (DCT) and the Cell Counting Kit (CCK)-8 assay at 60, 90 and 120 min. In addition, counting of colony-forming units (CFU) and live/dead cell staining were used to evaluate the anti-bacterial effects. The results of the DCT and CCK-8 assays indicated that Dios had beneficial dose-dependent inhibitory effects on P. gingivalis and P. intermedia. The CFU counting results also indicated that Dios had dose-dependent anti-bacterial effects on P. gingivalis and P. intermedia. Of note, Dios had significant anti-bacterial effects on the biofilms of P. gingivalis and P. intermedia in vitro as visualized by the live/dead cell staining method. In conclusion, the present results demonstrated that Dios had a marked anti-bacterial activity against P. gingivalis and P. intermedia in vitro, both in suspension and on biofilms. The present study highlighted the potential applications of Dios as a novel natural agent to prevent and treat periodontitis through its anti-bacterial effects.

Sugary Snack Consumption and Tooth Retention among Middle-aged Thai Adults

Objectives:

This study investigated whether the habit of consuming sugary snacks was independently associated with the loss of permanent teeth.

Materials and Methods:

Eight hundred ninety-seven adults aged 35–65 from four communities in the lower regions of Southern Thailand completed a structured questionnaire interview and dental examinations. The independent variable was frequency of sweet snack consumption between meals in the previous week and coded as: never (0 days), occasionally (1–4 days), or frequently (≥5 days). The outcome was the number of permanent teeth (1–19 vs. ≥20 teeth). Multivariate logistic regression was used to examine the adjusted associations between sugary snack consumption and the number of retained teeth. Odds ratio (OR) and 95% confidence intervals (CI) were calculated.

Results:

Approximately 23% of participants retained fewer than 20 permanent teeth. Approximately 30% of participants reported sugary snack intake most days. Fewer teeth were positively associated with high-frequency sugary snack consumption, older age, Muslim, ≤ 6 years of education, universal healthcare, infrequent tooth brushing, smoking, and alcohol consumption, but not sugar-sweetened beverages. After adjusting for sociodemographic characteristics and other potential confounders, the odds of having fewer teeth were higher among participants who frequently consumed sugary snacks (OR = 2.03, 95% CI = 1.21–3.39), but was not significantly different from those who occasionally consumed sugary snacks (OR = 0.93; 95% CI = 0.58–1.50) compared to nonsugary snack consumers.

Conclusion:

In this study, habitual sugary snack intake was associated with fewer teeth among middle-aged Thai adults. To improve oral health and prevent further tooth loss, efforts to reduce sugary snack consumption would be needed.

Aggregatibacter actinomycetemcomitans serotypes and JP2 outcomes related to clinical status over 6 years under periodontal maintenance therapy

OBJECTIVE

This 6-year study evaluatedAggregatibacter actinomycetemcomitans outcomes and their relationship to clinical status.

DESIGN

From the eligible individuals (23-70 years of age), 31 regular compliers (between-visit interval < 6 months) were randomly selected and matched for age/sex with 31 irregular compliers (between-visit interval > 6 months). Periodontal clinical examination and subgingival samples were obtained 5 times: T1 (baseline), T2 (after active periodontal therapy), T3 (2 years), T4 (4 years), and T5 (6 years). Total bacteria load, A. actinomycetemcomitans, and red complex species Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola levels were determined by qPCR while PCR was used to determine the occurrence of the a-b-c-d-e-f-g serotypes and the JP2 clone of A. actinomycetemcomitans. Data between groups was compared over time.

RESULTS

At baseline PCR revealed A. actinomycetemcomitans prevalence of 9.7 % and JP2 prevalence of 6.7 %. A. actinomycetemcomitans qPCR levels were higher among individuals < 35 years of age and increased at T2 in irregular compliers. At in irregular compliers at the three follow-up visits. Serotypes a, d, and f showed greater values in at least one follow-up visit in regular compliers. A. actinomycetemcomitans showed negative correlation with probing depth (PD) while serotype b showed negative correlations with PD, PI, clinical attachment level and red complex.

CONCLUSIONS

Longitudinally, compliance during PMT contributed to lower A. actinomycetemcomitans levels with some degree of correlation with clinical status. However, this study failed to report any positive effect on the occurrence of the most virulent representatives, i.e. serotype b and the JP2 clone.

Relationship of Salivary Microbiome with the Worsening of the Periodontal Health Status in Young Adults: A 3-Year Cohort Study

The purpose of this prospective cohort study was to investigate the influence of the salivary microbiome on the worsening of the periodontal health status among Japanese young adults. We assessed the data of systemically healthy and non-smoking young (18–22 years) university students (n = 457) from Okayama University at baseline (2013) and follow-up (2016). The worsening group was defined based on an increase in the percentage of bleeding on probing (%BOP) or an increase in probing pocket depth (PPD) from <4 mm to ≥4 mm. Unstimulated saliva samples were randomly collected from 69 students for microbiome analysis at follow-up. The salivary microbiome was assessed through 16S rRNA metagenomic sequencing. The type of community in the salivary microbiome clustered by statistical analysis and diversity was not significantly associated with the worsening of the periodontal health status in cases of increasing %BOP and PPD (p > 0.05). The prevalence of some species was significantly higher in the worsening group than in the non-worsening group (p < 0.05) in both cases. The worsening of the periodontal health status was associated with some species, but not the type of community and diversity in the salivary microbiome among Japanese young adults.

Age-Specific Predictive Models of the Upper Quintile of Periodontal Attachment Loss

A practical method to identify people who are most affected by periodontitis in their age group is currently unavailable. We focused on individuals with mean clinical attachment loss (CAL) above the 80th percentile within each of 10 age groups (5-y intervals between 30 and 74 y as well as ≥75 y). We developed predictive models using combined data from 2 cohorts (2009 to 2010 and 2011 to 2012) from the NHANES (National Health and Nutrition Examination Survey; development cohort [DC], n = 6,757), and we carried out external validation using data from a third NHANES cohort (2013 to 2014; validation cohort [VC], n = 3,447). We used 1) age-specific logistic regression models with stepwise selection to identify significant demographic variables, habits, medical conditions, and selected clinical periodontal parameters (proportion of teeth with probing depth ≥4 mm at incisors and molars and with visible [≥2 mm] recession) and to calculate propensity scores (PSs); 2) Youden's J statistic to select optimum PS cutoffs to maximize diagnostic performance using receiver operating characteristic curves; and 3) bootstrap resampling with 1,000 replicates to validate the age-specific models and adjust the PS and optimal PS cutoffs for overfitting. The bootstrap-adjusted PSs were used as single predictors of mean CAL over the 80th percentile in the VC. The age-specific upper quintiles of mean CAL ranged between 1.63 and 3.24 mm in the DC and between 1.87 and 3.20 mm in the VC. The area under the curve of the models exceeded 0.85 in all age groups in the DC and 0.84 in the VC, indicating well-validated diagnostic performance. In the DC, sensitivity values ranged between 0.75 and 0.97 and exceeded 0.83 in 8 of 10 age groups. Corresponding values in the VC ranged between 0.56 and 0.89 and exceeded 0.68 in 8 of 10 age groups. We conclude that modeling that incorporates readily obtainable variables through a brief patient interview and an abbreviated periodontal examination accurately identifies individuals who are most affected by periodontitis in different ages.

Genetic Profiling of Aggregatibacter actinomycetemcomitans Serotype B Isolated from Periodontitis Patients Living in Sweden

The bacterium Aggregatibacter actinomycetemcomitans is associated with aggressive forms of periodontitis and with systemic diseases, such as endocarditis. By assessing a Ghanaian longitudinal adolescent cohort, we earlier recognized the cagE gene as a possible diagnostic marker for a subgroup of JP2 and non-JP2 genotype serotype b A. actinomycetemcomitans strains, associated with high leukotoxicity as determined in a semi-quantitative cell assay. This group of A. actinomycetemcomitans is associated with the progression of attachment loss. In the present work, we used conventional polymerase chain reaction (PCR) and quantitative PCR to perform the cagE genotyping of our collection of 116 selected serotype b A. actinomycetemcomitans strains, collected over a period of 15 years from periodontitis patients living in Sweden. The A. actinomycetemcomitans strains carrying cagE (referred to as cagE⁺; n = 49) were compared to the cagE-negative strains (n = 67), present at larger proportions in the subgingival plaque samples, and were also much more prevalent in the young (≤35 years) compared to in the old (>35 years) group of patients. Our present results underline the potential use of cagE genotyping in the risk assessment of the development of periodontal attachment loss in Swedish adolescents.

Association between severity of periodontitis and clinical activity in rheumatoid arthritis patients: a case-control study

Background

A high prevalence of periodontitis has been reported in rheumatoid arthritis (RA) patients, although the strength of this association, its temporal link and the possible relationship between the severity of periodontitis and RA disease activity remain unclear. The objective of this work was to investigate whether periodontitis is associated with RA and whether periodontitis severity is linked to RA disease activity.

Methods

This case–control study included 187 patients diagnosed with RA and 157 control patients without inflammatory joint disease. RA disease activity and severity were evaluated by the Disease Activity Score 28, the Simplified Disease Activity Index, the Clinical Disease Activity Index, rheumatoid factor, anti-citrullinated protein antibody titers, the erythrocyte sedimentation rate, C-reactive protein, presence of extra-articular manifestations and type of RA therapy. Exposure severity was assessed by the following periodontal parameters: plaque index, bleeding on probing, probing pocket depth and clinical attachment levels. Sociodemographic variables and comorbidities were evaluated as confounding variables. Outcome and exposure variables were compared by both parametric and nonparametric tests, and possible associations were assessed through regression analysis with a calculation for the adjusted odds ratio (OR).

Results

A significant association was demonstrated between periodontitis and RA with an adjusted OR of 20.57 (95% CI 6.02–70.27, p < 0.001). Compared with controls, all parameters related to periodontal status (plaque index, bleeding on probing, probing pocket depth and clinical attachment levels) were significantly worse in RA patients (p < 0.001). Periodontitis severity was significantly associated with RA disease activity (p < 0.001), showing in an ordinal logistic regression model an association between periodontal severity and disease activity with an adjusted OR of 2.66 (95% CI 1.24–5.74, p = 0.012).

Conclusion

A significant association was demonstrated between periodontitis and RA, independent of other confounders. This association was more evident in patients with pronounced periodontal disease and higher RA disease activity.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1808-z) contains supplementary material, which is available to authorized users.

In vitro effect of diode laser against biofilm of Aggregatibacter actinomycetemcomitans

Objective:

The main objective is to investigate the antibacterial effect of diode laser against Aggregatibacter actinomycetemcomitans biofilm.

Materials and Methods:

Biofilms of A. actinomycetemcomitans plus Streptococcus sanguinis grown on bovine root surfaces were treated with an 810-nm diode laser using a noncontact pulsed mode with a pulse interval and pulse length of 20 ms. Four protocols, that is, one episode of 1.5 or 2.5 W for 30 s and three episodes of 1.5 or 2.5 W for 30 s were tested. No treatment and 0.2% chlorhexidine treatment served as negative and positive controls, respectively. Viable bacterial number was determined by colony counting.

Results:

Treatment with chlorhexidine and all laser protocols except that using single episode of 1.5 W reduced the number of A. actinomycetemcomitans in either single-species or dual-species biofilm compared to negative control. A higher percentage of A. actinomycetemcomitans reduction was demonstrated after increasing the power output or repeating the irradiation.

Conclusions:

The laser protocols used in this study could reduce the number of viable bacteria but not eradicate A. actinomycetemcomitans biofilm.

Building oral health research infrastructure: the first national oral health survey of Rwanda

Background: Oral health affects quality of life and is linked to overall health. Enhanced oral health research is needed in low- and middle-income countries to develop strategies that reduce the burden of oral disease, improve oral health and inform oral health workforce and infrastructure development decisions.

Objective: To implement the first National Oral Health Survey of Rwanda to assess the oral disease burden and inform oral health promotion strategies.

Methods: In this cross-sectional study, sample size and site selection were based on the World Health Organization (WHO) Oral Health Surveys Pathfinder stratified cluster methodologies. Randomly selected 15 sites included 2 in the capital city, 2 other urban centers and 11 rural locations representing all provinces and rural/urban population distribution. A minimum of 125 individuals from each of 5 age groups were included at each site. A Computer Assisted Personal Instrument (CAPI) was developed to administer the study instrument.

Results: Nearly two-thirds (64.9%) of the 2097 participants had caries experience and 54.3% had untreated caries. Among adults 20 years of age and older, 32.4% had substantial oral debris and 60.0% had calculus. A majority (70.6%) had never visited an oral health provider. Quality-of-life challenges due to oral diseases/conditions including pain, difficulty chewing, self-consciousness, and difficulty participating in usual activities was reported at 63.9%, 42.2% 36.2%, 35.4% respectively.

Conclusion: The first National Oral Health Survey of Rwanda was a collaboration of the Ministry of Health of Rwanda, the University of Rwanda Schools of Dentistry and Public Health, the Rwanda Dental Surgeons and Dental (Therapists) Associations, and Tufts University and Harvard University Schools of Dental Medicine. The international effort contributed to building oral health research capacity and resulted in a national oral health database of oral disease burden. This information is essential for developing oral disease prevention and management strategies as well as oral health workforce and infrastructure.

Antimicrobial susceptibilities of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis strains from periodontitis patients in Morocco

BACKGROUND AND OBJECTIVE

Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis have been frequently isolated in periodontitis patients in Morocco. Its persistence after the subgingival debridement of the biofilm has been correlated with worse clinical outcomes. The aim of this study was to evaluate the antimicrobial susceptibilities of A. actinomycetemcomitans and P. gingivalis, to amoxicillin, amoxicillin plus clavulanate, metronidazole, and azithromycin. In addition, microbiological profiles of patients harbouring A. actinomycetemcomitans, P. gingivalis, or both were compared.

MATERIAL AND METHODS

In 45 consecutive periodontitis Moroccan patients, subgingival samples were taken and processed by culture. Twenty-four A. actinomycetemcomitans and 30 P. gingivalis colonies were isolated (54 strains) and susceptibility tests, using the epsilometric method, were run for amoxicillin, amoxicillin plus clavulanate, metronidazole, and azithromycin. Minimum inhibitory concentrations for 50 (MIC50) and 90% (MIC90) of the organisms were calculated.

RESULTS

The prevalence of A. actinomycetemcomitans and P. gingivalis was 79.5 and 84.4%, respectively. A. actinomycetemcomitans showed susceptibility to amoxicillin, amoxicillin plus clavulanate, while 28% of the isolated strains were resistant to azithromycin and 61.7% towards metronidazole. No P. gingivalis resistance towards amoxicillin, amoxicillin plus clavulanate, metronidazole, and azithromycin was found.

CONCLUSION

A. actinomycetemcomitans and P. gingivalis were frequently detected in Moroccan patients with periodontitis, while antimicrobial resistance was only detected for A. actinomycetemcomitans to metronidazole and azithromycin.

CLINICAL RELEVANCE

A. actinomycetemcomitans resistance against some antimicrobials in periodontitis patients in Morocco can influence the selection of the therapeutic approaches.

Prevalence of gingivitis and calculus in 12-year-old Puerto Ricans: a cross-sectional study

Background

Gingivitis is a common oral health problem. Untreated gingivitis may progress to periodontitis, a common cause of tooth loss. The prevalence of gingivitis and calculus among Puerto Rican children is unknown. Understanding this prevalence can support early public health preventative strategies. This study aims to estimate the prevalence of gingivitis and calculus among 12-year-old Puerto Ricans by health region and to explore differences in distribution by school type (proxy for socio-economic status) and gender.

Methods

A probability-based sample of 113 schools was selected proportional to enrollment size and stratified by health region, school type, and gender. Two trained examiners evaluated the presence of gingivitis and both supragingival and subgingival dental calculus. Gingivitis was defined as the presence of gingival bleeding upon gentle probing (BOP) in at least one site, and the extent of the problem was classified according to the percentage of teeth whose gingiva presented BOP (limited: 25–49% of the teeth tested; extensive: >50% of teeth tested). Logistic and linear regression models, adjusted for health regions, were used to compare gingivitis and calculus prevalence and extent between genders and school types.

Results

Gingivitis was found in 80.41% of the 1586 children evaluated. Urban-public schoolchildren had a slightly higher prevalence (83.24%) compared to private (79.15%, p = 0.16); those in rural-public (77.59%) and private schools had similar prevalence (p = 0.15). Extensive gingivitis was present in 60.81% of all children. The mean percentage of sites presenting BOP (BOP%) was 17.79%. Rural and urban public schoolchildren presented significantly higher BOP% compared to children from private schools (p = 0.0005, p = 0.002, respectively). Dental calculus was detected in 61.59% of the sample, boys presenting significantly higher (p = 0.005) total and supragingival calculus. Rural-public schoolchildren had a significantly higher prevalence of subgingival calculus compared to private schoolchildren (p = 0.02).

Conclusions

Gingivitis prevalence is higher among 12-year-old Puerto Ricans compared to data reported for U.S. adolescents. Public schoolchildren presented significantly higher BOP% sites compared to private schoolchildren. Boys presented a significantly higher total and supragingival calculus prevalence than girls. Oral health disparities related to gender and school type were identified by this study. Studies exploring the reasons for these disparities are recommended.

Electronic supplementary material

The online version of this article (10.1186/s12903-017-0471-5) contains supplementary material, which is available to authorized users.

Natural history of periodontitis: Disease progression and tooth loss over 40 years

OBJECTIVES

To assess long-term attachment and periodontitis-related tooth loss (PTL) in untreated periodontal disease over 40 years.

MATERIAL AND METHODS

Data originated from the natural history of periodontitis study in Sri Lankan tea labourers first examined in 1970. In 2010, 75 subjects (15.6%) of the original cohort were re-examined.

RESULTS

PTL over 40 years varied between 0 and 28 teeth (mean 13.1). Four subjects presented with no PTL, while 12 were edentulous. Logistic regression revealed attachment loss as a statistically significant covariate for PTL (p < .004). Markov chain analysis showed that smoking and calculus were associated with disease initiation and that calculus, plaque, and gingivitis were associated with loss of attachment and progression to advanced disease. Mean attachment loss <1.81 mm at the age of 30 yielded highest sensitivity and specificity (0.71) to allocate subjects into a cohort with a dentition of at least 20 teeth at 60 years of age.

CONCLUSIONS

These results highlight the importance of treating early periodontitis along with smoking cessation, in those under 30 years of age. They further show that calculus removal, plaque control, and the control of gingivitis are essential in preventing disease progression, further loss of attachment and ultimately tooth loss.

Periodontal diseases

Periodontal diseases comprise a wide range of inflammatory conditions that affect the supporting structures of the teeth (the gingiva, bone and periodontal ligament), which could lead to tooth loss and contribute to systemic inflammation. Chronic periodontitis predominantly affects adults, but aggressive periodontitis may occasionally occur in children. Periodontal disease initiation and propagation is through a dysbiosis of the commensal oral microbiota (dental plaque), which then interacts with the immune defences of the host, leading to inflammation and disease. This pathophysiological situation persists through bouts of activity and quiescence, until the affected tooth is extracted or the microbial biofilm is therapeutically removed and the inflammation subsides. The severity of the periodontal disease depends on environmental and host risk factors, both modifiable (for example, smoking) and non-modifiable (for example, genetic susceptibility). Prevention is achieved with daily self-performed oral hygiene and professional removal of the microbial biofilm on a quarterly or bi-annual basis. New treatment modalities that are actively explored include antimicrobial therapy, host modulation therapy, laser therapy and tissue engineering for tissue repair and regeneration.

Assessment of periodontal bone level revisited: a controlled study on the diagnostic accuracy of clinical evaluation methods and intra-oral radiography

OBJECTIVES

The accuracy of analogue and especially digital intra-oral radiography in assessing interdental bone level needs further documentation. The aim of this study was to compare clinical and radiographic bone level assessment to intra-surgical bone level registration (1) and to identify the clinical variables rendering interdental bone level assessment inaccurate (2).

MATERIALS AND METHODS

The study sample included 49 interdental sites in 17 periodontitis patients. Evaluation methods included vertical relative probing attachment level (RAL-V), analogue and digital intra-oral radiography and bone sounding without and with flap elevation. The latter was considered the true bone level. Five examiners evaluated all radiographs.

RESULTS

Significant underestimation of the true bone level was observed for all evaluation methods pointing to 2.7 mm on average for analogue radiography, 2.5 mm for digital radiography, 1.8 mm for RAL-V and 0.6 mm for bone sounding without flap elevation (p < 0.001). Radiographic underestimation of the true bone level was higher in the (pre)molar region (p ≤ 0.047) and increased with defect depth (p < 0.001). Variation between clinicians was huge (range analogue radiography 2.2-3.2 mm; range digital radiography 2.1-3.0 mm).

CONCLUSION

All evaluation methods significantly underestimated the true bone level. Bone sounding was most accurate, whereas intra-oral radiographs were least accurate. Deep periodontal defects in the (pre)molar region were most underrated by intra-oral radiography.

CLINICAL RELEVANCE

Bone sounding had the highest accuracy in assessing interdental bone level.

Root abnormalities and nonsurgical management of generalized aggressive periodontitis

To investigate long-term nonsurgical treatment outcomes in patients with generalized aggressive periodontitis (GAgP) and the impact of root abnormalities (RAs) and other patient-level factors in relation to GAgP progression. Patients (n = 64) from a GAgP cohort who completed active nonsurgical periodontal treatment and consented to re-evaluation after 3 to 11 (mean 5.3) years, were enrolled. RAs were identified using radiographs. Periodontal parameters (e.g., probing depths [PDs], and tooth loss [TL]) were investigated. Multivariate analysis was performed to identify factors contributing to TL and bone level alteration (∆BL). After treatment, the mean number of sites with PDs > 5 mm decreased from 54.3 to 17.2. Annual TL was 0.11/patient. Twenty-one patients (32.8%) had >4 teeth with root abnormalities (RA-teeth) and exhibited a higher risk for TL (univariate odds ration [OR] = 3.52, multivariate logistic OR = 6.57). Factors correlated to ∆BL were sites with residual PD > 5 mm (β = -0.400) and observation time (β = -0.210). Nonsurgical treatment provides beneficial outcomes in GAgP patients. Higher incidence of RAs and high prevalence of residual deep pockets have a negative impact on long-term outcomes.

PRACTICAL IMPLICATIONS

in cases of GAgP with residual deep pockets and high incidence of RAs, clinicians must emphasize that long-term outcomes of nonsurgical treatment may be compromised.

Introduction to Clinical Microbiology for the General Dentist

Clinical oral microbiology may help dental professionals identify infecting pathogenic species and evaluate their in vitro antimicrobial susceptibility. Saliva, dental plaque biofilms, mucosal smears, abscess aspirates, and soft tissue biopsies are sources of microorganisms for laboratory testing. Microbial-based treatment end points may help clinicians better identify patients in need of additional or altered dental therapies before the onset of clinical treatment failure, and help improve patient oral health outcomes. Microbiological testing appears particularly helpful in periodontal disease treatment planning. Further research and technological advances are likely to increase the availability and clinical utility of microbiological analysis in modern dental practice.

Assessing the progression of chronic periodontitis using subgingival pathogen levels: a 24-month prospective multicenter cohort study

BACKGROUND

The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients.

METHODS

This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis.

RESULTS

Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708).

CONCLUSIONS

The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Risk factors in periodontology: a conceptual framework

AIM

The definition and assessment of risk factors, risk indicators and predisposing factors are of paramount importance in the understanding of the pathogenesis of periodontitis, as well as in its prevention and treatment. This article aims to emphasize the concepts of causal chains and the causal network of risk factors in periodontitis.

MATERIALS AND METHODS

This is a narrative review focusing on two main questions: (1) what is a risk in periodontology? and (2) how can a risk be assessed?

RESULTS

The probability of the occurrence of an adverse outcome following exposure is not sufficient to analyse the impact of a risk factor on the disease. A network model for the pathway of risk factors in the pathogenesis of periodontitis is described. This article emphasizes the concepts of causal chains and the causal network of risk factors in periodontitis.

CONCLUSION

Chronic periodontal diseases are among the most complex non-communicable diseases. A conceptual framework intended to clarify the relationship between risk and causality may improve the understanding of the underlying mechanisms of chronic diseases. The proposed causal network may provide a model to assess the role of risk factors in periodontitis.

Association between Polymorphisms in Interleukins 4 and 13 Genes and Chronic Periodontitis in a Han Chinese Population

Chronic periodontitis (CP) is one of the most common chronic inflammatory diseases and cytokines play a pivotal role in the regulation of immune response. Interleukin-4 (IL-4) and interleukin-13 (IL-13) are anti-inflammatory cytokines and several polymorphisms of them have been proved involved in periodontal disease. This study aimed to evaluate whether three single nucleotide polymorphisms (SNPs), rs2070874 and rs2243248 from IL4 and rs1800925 from IL13, are associated with CP in a Han Chinese population consisting of 440 moderate or severe CP patients and 324 healthy controls. Genomic DNA extracted from buccal epithelial cells of the included participants were genotyped using a matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry method. No significant association between rs2070874 or rs1800925 and CP was found, while the frequencies of rs2243248 and two haplotypes C-G-T and C-T-T showed significant differences between the two groups. The results suggest that the polymorphism rs2243248 and haplotypes C-G-T and C-T-T may be associated with CP susceptibility in the present Han Chinese population.

Aggregatibacter actinomycetemcomitans: virulence of its leukotoxin and association with aggressive periodontitis

Periodontitis is an infection-induced inflammatory disease that causes loss of the tooth supporting tissues. Much focus has been put on comparison of the microbial biofilm in the healthy periodontium with the diseased one. The information arising from such studies is limited due to difficulties to compare the microbial composition in these two completely different ecological niches. A few longitudinal studies have contributed with information that makes it possible to predict which individuals who might have an increased risk of developing aggressive forms of periodontitis, and the predictors are either microbial or/and host-derived factors. The most conspicuous condition that is associated with disease risk is the presence of Aggregatibacter actinomycetemcomitans at the individual level. This Gram-negative bacterium has a great genetic variation with a number of virulence factors. In this review we focus in particular on the leukotoxin that, based on resent knowledge, might be one of the most important virulence factors of A. actinomycetemcomitans.

Aggressive Periodontitis: microbes and host response, who to blame?

A paradigm shift several decades ago elucidated that aggressive periodontitis (AgP) was not a degenerative disorder but a rapid progressive form of plaque-induced inflammatory periodontal disease. Ensuing years of research have led to linkage analysis identification of specific genetic defects responsible for AgP in some families and to the finding that subgingival detection of A. actinomycet-emcomitans JP2 clone is a predictive factor for disease onset and progression. However, rather disappointingly, these ‘proven’ risk factors are only detected in a small subset of AgP cases. Recent advances are leading to a new paradigm shift, with the realization that genetically-driven dysbiotic changes in the subgingival microbiota may predispose to a cascade of events leading to the rapid periodontal tissue destruction seen in AgP. This review tries to dissect the existing literature on the host response-microbial axis of AgP and to propose possible pathogenic pathways in line with current theories.

Java project on periodontal diseases: effect of vitamin C/calcium threonate/citrus flavonoids supplementation on periodontal pathogens, CRP and HbA1c

OBJECTIVE

To assess in a periodontally diseased rural population deprived from regular dental care and having poor dietary conditions, the effect of vitamin C/calcium threonate/citrus flavonoids (VitC/Ca/Fl) supplementation on subgingival microbiota and plasma levels of vitamin C, HbA1c and hsCRP.

MATERIAL & METHODS

The study population consisted of 98 subjects who previously participated in a prospective study on the natural history of periodontitis. Participants were instructed to consume one tablet/day containing 200 mg Ester C(®) calcium ascorbate, 25 mg calcium threonate and 100 mg citrus flavonoids for 90 days. Following parameters were evaluated: prevalence/amount of seven traditional periodontal pathogens, cytomegalovirus, Epstein-Barr virus (EBV); and plasma levels of vitamin C, HbA1c and hsCRP.

RESULTS

After VitC/Ca/Fl supplementation, 100% of subjects showed normal plasma vitamin C values compared to 55% before. At baseline, 48% of subjects harboured Aggregatibacter actinomycetemcomitans, >97% the other periodontal pathogens and 73% EBV. Supplementation with VitC/Ca/F reduced the subgingival load of all studied bacteria (p-values: 0.014-0.0001) and EBV (p < 0.0001) substantially in all initially positive subjects. Plasma levels of HbA1c and hsCRP dropped in all subjects (p < 0.0001).

CONCLUSION

This uncontrolled study suggested that supplemental VitC/Ca/Fl may be helpful in reducing subgingival numbers of periodontal pathogens and EBV, and promoting systemic health.

Microbiology of aggressive periodontitis

For decades, Aggregatibacter actinomycetemcomitans has been considered the most likely etiologic agent in aggressive periodontitis. Implementation of DNA-based microbiologic methodologies has considerably improved our understanding of the composition of subgingival biofilms, and advanced open-ended molecular techniques even allow for genome mapping of the whole bacterial spectrum in a sample and characterization of both the cultivable and not-yet-cultivable microbiota associated with periodontal health and disease. Currently, A. actinomycetemcomitans is regarded as a minor component of the resident oral microbiota and as an opportunistic pathogen in some individuals. Its specific JP2 clone, however, shows properties of a true exogenous pathogen and has an important role in the development of aggressive periodontitis in certain populations. Still, limited data exist on the impact of other microbes specifically in aggressive periodontitis. Despite a wide heterogeneity of bacteria, especially in subgingival samples collected from patients, bacteria of the red complex in particular, and those of the orange complex, are considered as potential pathogens in generalized aggressive periodontitis. These types of bacterial findings closely resemble those found for chronic periodontitis, representing a mixed polymicrobial infection without a clear association with any specific microorganism. In aggressive periodontitis, the role of novel and not-yet-cultivable bacteria has not yet been elucidated. There are geographic and ethnic differences in the carriage of periodontitis-associated microorganisms, and they need to be taken into account when comparing study reports on periodontal microbiology in different study populations. In the present review, we provide an overview on the colonization of potential periodontal pathogens in childhood and adolescence, and on specific microorganisms that have been suspected for their role in the initiation and progression of aggressive forms of periodontal disease.

Trends of periodontal conditions in two different randomly selected Swiss (Bernese) cohorts 25 years apart

AIM

To assess the periodontal conditions of two randomly selected Swiss cohorts 25 years apart.

MATERIAL AND METHODS

Standardized examinations were performed to assess the periodontal conditions of two randomly selected populations of the Canton of Bern; oral cleanliness was evaluated using the plaque index (PlI) and the retention index (RI). Gingival health was scored according to the gingival index (GI). Periodontal conditions were evaluated by pocket probing depth (PPD) and loss of attachment (LA).

RESULTS

At the first examination in 1985, 206 out of 350 subjects were evaluated, while in the second examination in 2010, 134 out of 490 subjects attended the examinations. In 1985, subjects showed a mean PlI of 1.16, and 0.77 in 2010. RI was 0.81 and 0.36 in 1985 and 2010 respectively. Mean GI was 1.34 and 0.6. The mean proportion of PPD ≤3 mm was 72% in 1985 and 97.3% in 2010. PPD ≥ 6 mm affected 2.0% in 1985 and 0.3% in 2010. In 1985, subjects had an average of 20.7 teeth, while in 2010, the average was 24.6. In 1985, 7.3% of the subjects were edentulous, while in 2010, 4.5% had no teeth.

CONCLUSIONS

Trends to improvements resulting in more teeth in function and better periodontal conditions were recognized.