Can presence or absence of periodontal pathogens distinguish between subjects with chronic and aggressive periodontitis? A systematic review

A Novel Therapeutic Calcium Peroxide Loaded Injectable Bio-adhesive Hydrogel Against Periodontitis

OBJECTIVES

Periodontitis is a prevalent oral disease that can significantly impact patients' life quality and systemic health. However, non-surgical subgingival scaling is largely compromised due to poor patient compliance, leading to a high recurrence rate of periodontitis. Therefore, this research aims to explore new approaches to enhance the effectiveness of existing local drug administration therapies.

MATERIALS AND METHODS

Gelatin-oxidized dextran hydrogel loaded with calcium peroxide and penicillin (CP-P hydrogel) was synthesized and characterized using Universal mechanical testing machine, Fourier transform infrared spectroscopy, swelling test, and dissolved oxygen meter. Furthermore, the cytotoxicity, osteogenic ability, antibacterial behavior, and alveolar bone regenerating capability of CP-P hydrogel were conducted both in vitro and in vivo.

RESULTS

The CP-P hydrogel demonstrated excellent mechanical properties, minimal swelling, and ideal biocompatibility. It created more favorable environments in the periodontal pocket by reversing anaerobic environment, eliminating drug-resistant bacteria and enhancing the therapeutic potency of drugs. By continuously releasing drugs in the periodontal pocket, the CP-P hydrogel effectively inhibited bacteria and reduce local inflammation response. In addition to bacteriostatic effects, the CP-P hydrogel also promoted the expression of osteogenic genes and enhanced osteogenic differentiation of PDLSCs in vitro.

CONCLUSIONS

CP-P hydrogel can be developed as a new therapeutic platform to enhance the effectiveness of local drug administration strategy against periodontitis.

Etiology, pathogenesis and treatment of peri-implantitis: A European perspective

Peri-implantitis is a plaque-associated pathological condition occurring in tissues around dental implants. It is characterized by inflammation in the peri-implant mucosa and progressive loss of supporting bone. Over the last 30 years, peri-implantitis has become a major disease burden in dentistry. An understanding of the diagnosis, etiology and pathogenesis, epidemiology, and treatment of peri-implantitis must be a central component in undergraduate and postgraduate training programs in dentistry. In view of the strong role of European research in periodontology and implant dentistry, the focus of this review was to address peri-implantitis from a European perspective. One component of the work was to summarize new and reliable data on patients with dental implants to underpin the relevance of peri-implantitis from a population perspective. The nature of the peri-implantitis lesion was evaluated through results presented in preclinical models and evaluations of human biopsy material together with an appraisal of the microbiological characteristics. An overview of strategies and outcomes presented in clinical studies on nonsurgical and surgical treatment of peri-implantitis is discussed with a particular focus on end points of therapy and recommendations presented in the S3 level Clinical Practice Guideline for the prevention and treatment of peri-implant diseases.

Microbial biomarkers as a predictor of periodontal treatment response: A systematic review

To evaluate the prognostic accuracy of microbial biomarkers and their associations with the response to active periodontal treatment (APT) and supportive periodontal therapy (SPT). Microbial dysbiosis plays a crucial role in the disease processes of periodontitis. Biomarkers based on microbial composition may offer additional prognostic value, supplementing the limitations of current clinical parameters. While these microbial biomarkers have been clinically evaluated, there is a lack of consensus regarding their prognostic accuracy. A structured search strategy was applied to MEDLINE (PubMed), Cochrane Library, and Embase on 1/11/2022 to identify relevant publications. Prospective clinical studies involving either APT or SPT, with at least 3-month follow-up were included. There were no restrictions on the type of microbial compositional analysis. 1918 unique records were retrieved, and 13 studies (comprising 943 adult patients) were included. Heterogeneity of the studies precluded a meta-analysis, and none of the included studies had performed the sequence analysis of the periodontal microbiome. Seven and six studies reported on response to APT and SPT, respectively. The prognostic accuracy of the microbial biomarkers for APT and SPT was examined in only two and four studies, respectively. Microbial biomarkers had limited predictive accuracy for APT and inconsistent associations for different species across studies. For SPT, elevated abundance of periodontal pathogens at the start of SPT was predictive of subsequent periodontal progression. Similarly, persistent high pathogen loads were consistently associated with progressive periodontitis, defined as an increased pocket probing depth or clinical attachment loss. While there was insufficient evidence to support the clinical use of microbial biomarkers as prognostic tools for active periodontal treatment outcomes, biomarkers that quantify periodontal pathogen loads may offer prognostic value for predicting progressive periodontitis in the subsequent supportive periodontal therapy phase. Additional research will be required to translate information regarding subgingival biofilm composition and phenotype into clinically relevant prognostic tools.

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.

Burden of chronic diseases associated with periodontal diseases: a retrospective cohort study using UK primary care data

OBJECTIVES

To identify the association between periodontal diseases (gingivitis and periodontitis) and chronic diseases including cardiovascular disease, cardiometabolic disease, autoimmune disease and mental ill health.

DESIGN

Retrospective cohort.

SETTING

IQVIA Medical Research Data-UK between 1 January 1995 and 1 January 2019.

PARTICIPANTS

64 379 adult patients with a general practitioner recorded diagnosis of periodontal disease (exposed patients) were matched to 251 161 unexposed patients by age, sex, deprivation and registration date.

MAIN OUTCOME MEASURES

Logistic regression models accounting for covariates of clinical importance were undertaken to estimate the adjusted OR (aOR) of having chronic diseases at baseline in the exposed compared with the unexposed group. Incidence rates for each outcome of interest were then provided followed by the calculation of adjusted HRs using cox regression modelling to describe the risk of outcome development in each group.

RESULTS

The average age at cohort entry was 45 years and the median follow-up was 3.4 years. At study entry, the exposed cohort had an increased likelihood of having a diagnosis of cardiovascular disease (aOR 1.43; 95% CI 1.38 to 1.48), cardiometabolic disease (aOR 1.16; 95% CI 1.13 to 1.19), autoimmune disease (aOR 1.33; 95% CI 1.28 to 1.37) and mental ill health (aOR 1.79; 95% CI 1.75 to 1.83) compared with the unexposed group. During the follow-up of individuals without pre-existing outcomes of interest, the exposed group had an increased risk of developing cardiovascular disease (HR 1.18; 95% CI 1.13 to 1.23), cardiometabolic disease (HR 1.07; 95% CI 1.03 to 1.10), autoimmune disease (HR 1.33; 95% CI 1.26 to 1.40) and mental ill health (HR 1.37; 95% CI 1.33 to 1.42) compared with the unexposed group.

CONCLUSIONS

In this cohort, periodontal diseases appeared to be associated with an increased risk of developing cardiovascular, cardiometabolic, autoimmune diseases and mental ill health. Periodontal diseases are very common; therefore, an increased risk of other chronic diseases represent a substantial public health burden.

Periodontology and pregnancy: An overview of biomedical and epidemiological evidence

Women are particularly susceptible to developing gingival problems during pregnancy. In addition, periodontal disease in pregnant women may lead to adverse outcomes for both mother and infant, which have serious clinical and public health implications. Both scenarios have been extensively researched, helping to bring attention to pregnant women as an important and vulnerable population as it concerns periodontal health. The increase in gingival inflammation caused by hormonal changes in pregnant women is undisputed and has been studied and documented since the 1960s, although the exact etiology is not fully understood. The relationship between periodontal disease during pregnancy and adverse pregnancy outcomes is less substantiated, because of conflicting evidence. This review of the biomedical and epidemiologic literature provides an overview of both sides of this relationship and examines the potential mechanisms for developing periodontal disease during pregnancy and the proposed mechanisms by which periodontal disease leads to adverse pregnancy outcomes.

Comparison of three qPCR-based commercial tests for detection of periodontal pathogens

In periodontal practice microbial results of periodontal test kits for identification of key pathogens are an aid in the treatment planning. Information on the performance of commercially available test kits is therefore essential for the clinician. In this retrospective analysis three commercially available qPCR kits for detection and quantification of selected periodontal bacterial species were compared, using 100 clinical samples from patients with untreated periodontitis. The analysis involved two separate comparisons in which kit A (LabOral Diagnostics, The Netherlands) was compared with kit B (Advanced Dental Diagnostics, The Netherlands), and with kit C (OralDent diagnostics, The Netherlands). Analytic procedures for detection and quantification of selected periodontal bacterial species were carried out according to the instructions of the laboratories. Kit A detected target species more often, and absolute numbers of bacterial cells were higher than with kit B. A high degree of similarity was found between the test outcomes by kit A and kit C. All three kits performed satisfactory but small and significant differences exist between kits.

Clinical and Microbiological Profiles of Aggressive and Chronic Periodontitis in Congolese Patients: A Cross-sectional Study

Background:

Chronic and aggressive periodontitis were the main forms of periodontitis according to the 1999 classification of periodontal diseases and conditions. Their profile in Congolese patients is still undescribed.

Aim:

The aim of this study was to compare the profile of chronic periodontitis (ChP) with that of aggressive periodontitis (AgP) in Congolese patients.

Materials and Methods:

Thirty-two patients with ChP and 20 with AgP who consulted the dental services at any of the four medical centers in Kinshasa, from April 2017 to April 2018, were enrolled in the cross-sectional study. All patients underwent a full mouth examination, including assessment of the probing pocket depth and clinical attachment level at six sites per tooth. Microbial samples were collected in the deepest pocket in the maxilla and the deepest pocket in the mandible. A deoxyribonucleic acid (DNA) analysis was performed using DNA strip technology. Fisher exact test, the chi-square test, the t test, and the Mann–Whitney test were used for the statistical analysis.

Results:

Patients with AgP were significantly younger than those with ChP (P < 0.001). There was no significant difference in the prevalence of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, or Prevotella intermedia between the AgP and ChP groups (P > 0.05). Aggregatibacter actinomycetemcomitans was detected in 10% of cases in the AgP group and in none of those in the ChP group (P = 0.143).

Conclusion:

This study shows that the clinical profiles of ChP and AgP are similar in Congolese patients. There were no microbiological differences between these two forms of periodontitis.

Oral Lactobacillus strains reduce cytotoxicity and cytokine release from peripheral blood mononuclear cells exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro

Background

This study evaluated the effect of oral lactobacilli on the cytotoxicity and cytokine release from peripheral blood mononuclear cells (PBMCs) when exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro. The supernatants and cell wall extracts (CWEs) of eight A. actinomycetemcomitans strains, representing different subtypes, and three Lactobacillus strains were used. The PBMCs from six blood donors were exposed to supernatants and CWEs of A. actinomycetemcomitans or Lactobacillus strains alone or combinations and untreated cells as control. The cytotoxicity was determined by trypan blue exclusion method and IL-1β secretion by ELISA. TNF-α, IL-6, and IL-8 secretions were measured using Bioplex Multiplex Immunoassay.

Results

Supernatants or CWEs from all bacterial strains showed cytotoxicity and IL-1β secretion and the subtypes of A. actinomycetemcomitans showed generally a significantly higher effect on PBMCs than that of the Lactobacillus strains. Two highly toxic A. actinomycetemcomitans strains (JP2 and JP2-like) induced a higher response than all other strains. When combined, Lactobacillus significantly reduced the toxicity and the IL-1β secretion induced by A. acinomycetemcomitans. The effect varied between the subtypes and the reduction was highest for the JP2 and JP2-like strains. The Lactobacillus paracasei strain SD1 had a higher reducing effect than the other Lactobacillus strains. This strain had a consistent reducing effect on all subtypes of A. actinomycetemcomitans cytotoxicity, and release of IL-1β, IL-6, IL-8, and TNF-α from PBMCs of the blood donors. A strong and significant variation in cytokine release between the six blood donors was noticed.

Conclusions

Lactobacillus spp. and L. paracasei SD1 in particular, showed a limited but statistically significant reducing interaction with A. actinomycetemcomitans toxicity and release of cytokines in vitro.

The Subgingival Microbiome Relationship to Periodontal Disease in Older Women

Understanding of the oral microbiome in relation to periodontal disease in older adults is limited. The composition and diversity of the subgingival microflora and their oligotypes in health and levels of periodontal disease were investigated in this study on older postmenopausal women. The 16S rRNA gene was sequenced using the Illumina MiSeq platform in 1,206 women aged 53 to 81 y. Presence and severity of periodontal disease were defined by Centers for Disease Control and Prevention/American Academy of Periodontology criteria. Composition of the microbiome was determined by 16S rRNA amplicon sequencing and the abundance of taxa described by the centered log₂-ratio (CLR) transformed operational taxonomic unit (OTU) values. Differences according to periodontal disease status were determined by analysis of variance with Bonferroni correction. Bacteria oligotypes associated with periodontal disease and health were determined by minimum entropy decomposition and their functions estimated in silico using PICRUSt. Prevalence of none/mild, moderate, and severe periodontal disease was 25.1%, 58.3%, and 16.6%, respectively. Alpha diversity of the microbiome differed significantly across the 3 periodontal disease categories. β-Diversity differed between no/mild and severe periodontal disease, although considerable overlap was noted. Of the 267 bacterial species identified at ≥0.02% abundance, 56 (20.9%) differed significantly in abundance according to periodontal disease status. Significant linear correlations for pocket depth and clinical attachment level with bacterial amounts were observed for several taxa. Of the taxa differing in abundance according to periodontal disease status, 53% had multiple oligotypes appearing to differ between none/mild and severe periodontal disease. Among older women, taxonomic differences in subgingival microbiome composition and diversity were observed in relation to clinical periodontal disease measures. Potential differences in bacterial subspecies (oligotypes) and their function were also identified in periodontal disease compared with health.

Do patients with aggressive and chronic periodontitis exhibit specific differences in the subgingival microbial composition? A systematic review

BACKGROUND

The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions grouped the diseases previously recognized as chronic (CP) or aggressive (AgP) periodontitis under a single category named periodontitis. The rationale for this decision was the lack of specific patterns of immune-inflammatory response or microbial profiles associated with CP or AgP. However, no previous studies have compiled the results of all studies comparing subgingival microbial data between these clinical conditions. Thus, this systematic review aimed to answer the following focused question: "Do patients with AgP periodontitis present differences in the subgingival microbiota when compared with patients with CP?"

METHODS

A systematic review was conducted according to the PRISMA statement. The MEDLINE, EMBASE, and Cochrane databases were searched up to June 2019 for studies of any design (except case reports, case series, and reviews) comparing subgingival microbial data from patients with CP and AgP.

RESULTS

A total of 488 articles were identified and 56 were included. Thirteen studies found Aggregatibacter actinomycetemcomitans elevated in AgP in comparison with CP, while Fusobacterium nucleatum, Parvimonas micra, and Campylobacter rectus were elevated in AgP in a few studies. None of these species were elevated in CP. However, the number of studies not showing statistically significant differences between CP and AgP was always higher than that of studies showing differences.

CONCLUSION

These results suggested an association of A. actinomycetemcomitans with AgP, but neither this species nor the other species studied to date were unique to or could differentiate between CP and AgP (PROSPERO #CRD42016039385).

Salivary markers of oxidative stress and periodontal pathogens in patients with periodontitis from Santander, Colombia

Introduction:

Periodontitis affects more than 20% of the Latin American population. Oxidative markers are associated with greater progression of periodontitis; therefore, its role in pathogenesis should be studied.

Objective:

To determine the prevalence of the main oral bacteria and viruses associated with periodontitis and estimate the total antioxidant capacity and lipid peroxidation in saliva from patients with periodontitis.

Materials and methods:

We conducted systemically a cross-sectional study in 101 healthy subjects, 87 of whom had been diagnosed with periodontitis (P), according to the criteria of the Centers of Disease Control and Prevention and the American Academy of Periodontology, and 14 without periodontal pockets as controls (C). In subgingival samples, major viruses and dental pathogenic bacteria were identified using PCR techniques. The levels of total antioxidant capacity and malon-di-aldehyde (MDA) were determined by spectrophotometry in samples of unstimulated saliva.

Results:

The mean of periodontal depth pocket and clinical attachment loss in patients with periodontitis was 5.6 ± 1.7 and 6.1 ± 3.1 mm, respectively. The most prevalent microorganisms were Aggregatibacter actinomycetemcomitans (32.5%) and Porphyromonas gingivalis (18.6%). The patients from rural areas showed a higher percentage of A. actinomycetemcomitans (urban: 17.9% vs. rural: 48.9%, p=0.0018). In patients with periodontitis, the frequency of EBV, HSV1 & 2, and HCMV genes was 2.3%. Periodontitis patients had higher levels of MDA (P: 2.1 ± 1.5; C: 0.46 ± 0.3 µmol/g protein; p=0.0001) and total antioxidant capacity (P: 0.32 ± 0.2; C: 0.15 ± 0.1 mM; p< 0.0036). Oxidative markers showed no modifications due to the presence of periodontopathic bacteria.

Conclusions:

Aggregatibacter actinomycetemcomitans was the most prevalent bacteria; its presence did not modify the levels of oxidative markers in the saliva of patients with periodontitis.

Interactions of Tea-Derived Catechin Gallates with Bacterial Pathogens

Green tea-derived galloylated catechins have weak direct antibacterial activity against both Gram-positive and Gram-negative bacterial pathogens and are able to phenotypically transform, at moderate concentrations, methicillin-resistant Staphylococcus aureus (MRSA) clonal pathogens from full β-lactam resistance (minimum inhibitory concentration 256-512 mg/L) to complete susceptibility (~1 mg/L). Reversible conversion to susceptibility follows intercalation of these compounds into the bacterial cytoplasmic membrane, eliciting dispersal of the proteins associated with continued cell wall peptidoglycan synthesis in the presence of β-lactam antibiotics. The molecules penetrate deep within the hydrophobic core of the lipid palisade to force a reconfiguration of cytoplasmic membrane architecture. The catechin gallate-induced staphylococcal phenotype is complex, reflecting perturbation of an essential bacterial organelle, and includes prevention and inhibition of biofilm formation, disruption of secretion of virulence-related proteins, dissipation of halotolerance, cell wall thickening and cell aggregation and poor separation of daughter cells during cell division. These features are associated with the reduction of capacity of potential pathogens to cause lethal, difficult-to-treat infections and could, in combination with β-lactam agents that have lost therapeutic efficacy due to the emergence of antibiotic resistance, form the basis of a new approach to the treatment of staphylococcal infections.

JP2 Genotype of Aggregatibacter actinomycetemcomitans in Caucasian Patients: A Presentation of Two Cases

Aggregatibacter actinomycetemcomitans is a key pathogen that has been associated with periodontal disease. Its most important virulence factor is a leukotoxin capable of inactivating immune cells. The JP2 genotype of Aggregatibacter actinomycetemcomitans shows enhanced leukotoxic activity and is mostly present in individuals of North and West African origin with severe periodontitis. In this paper, two cases of Caucasians diagnosed with the JP2 genotype are presented. A 50-year-old female patient had three approximal sites with ≥ 6 mm clinical attachment loss (CAL) and eight sites with probing depth (PD) ≥ 5 mm. Microbiological diagnostics revealed A. actinomycetemcomitans JP2 genotype, but not Porphyromonas gingivalis. This JP2 genotype was highly leukotoxic to monocytic cells. The second case was a 55-year-old female patient with CAL of > 5 mm at all molars and PD of up to 12 mm. A. actinomycetemcomitans JP2 was identified, but not P. gingivalis. Her husband originated from North-Africa. In him, no A. actinomycetemcomitans was detected, but their 17-year-old daughter was diagnosed with periodontitis and was found to be positive for the JP2 genotype. Both patients were successfully treated with adjunctive antibiotics and the JP2 genotype was eliminated. In summary, here, the microbiological diagnosis was key for the treatment with adjunctive antibiotics.

Unique etiologic, demographic, and pathologic characteristics of localized aggressive periodontitis support classification as a distinct subcategory of periodontitis

BACKGROUND

Localized aggressive periodontitis (LAgP) occurs in 2% of African-American adolescents but only 0.15% of white adolescents. First molars and incisors are affected by rapid onset and progression.

METHODS

This nonsystematic critical review evaluated published data for LAgP and chronic periodontitis (CP), focusing on potential differences in epidemiology, microbiology, immunology, genetics, and response to therapy.

RESULTS

LAgP differs from CP by localization to incisors and first molars, early onset and rapid progression in adolescents and young adults, and a 10-fold higher prevalence in populations of African or Middle Eastern origin, often with strong familial aggregation. The bacterium Aggregatibacter actinomycetemcomitans and hyperresponsive neutrophils are frequently observed. Antibiotic and nonsurgical therapies are highly effective.

CONCLUSIONS

LAgP differs in many ways from the far more common CP that affects older adults. The substantial evidence of dissimilarities summarized in this review strongly supports the classification of LAgP as a distinct form of periodontitis.

PRACTICAL IMPLICATIONS

Classifying LAgP as a distinct subcategory of periodontitis will encourage future research and does not conflict with the newly proposed "staging and grading" system. The silent onset and rapid progression of LAgP make early diagnosis and frequent follow-up with patients essential for effective treatment.

Hidden noise in immunologic parameters might explain rapid progression in early-onset periodontitis

To investigate in datasets of immunologic parameters from early-onset and late-onset periodontitis patients (EOP and LOP), the existence of hidden random fluctuations (anomalies or noise), which may be the source for increased frequencies and longer periods of exacerbation, resulting in rapid progression in EOP. Principal component analysis (PCA) was applied on a dataset of 28 immunologic parameters and serum IgG titers against periodontal pathogens derived from 68 EOP and 43 LOP patients. After excluding the PCA parameters that explain the majority of variance in the datasets, i.e. the overall aberrant immune function, the remaining parameters of the residual subspace were analyzed by computing their sample entropy to detect possible anomalies. The performance of entropy anomaly detection was tested by using unsupervised clustering based on a log-likelihood distance yielding parameters with anomalies. An aggregate local outlier factor score (LOF) was used for a supervised classification of EOP and LOP. Entropy values on data for neutrophil chemotaxis, CD4, CD8, CD20 counts and serum IgG titer against Aggregatibacter actinomycetemcomitans indicated the existence of possible anomalies. Unsupervised clustering confirmed that the above parameters are possible sources of anomalies. LOF presented 94% sensitivity and 83% specificity in identifying EOP (87% sensitivity and 83% specificity in 10-fold cross-validation). Any generalization of the result should be performed with caution due to a relatively high false positive rate (17%). Random fluctuations in immunologic parameters from a sample of EOP and LOP patients were detected, suggesting that their existence may cause more frequently periods of disease activity, where the aberrant immune response in EOP patients result in the phenotype "rapid progression".

Association between circulating levels of heat-shock protein 27 and aggressive periodontitis

Heat-shock protein (Hsp) 27 is a major intracellular molecular chaperone and controller of intracellular responses to inflammatory signals. In the extracellular space, recombinant Hsp27 has been described to exert anti-inflammatory activities. The aim of this study was to assess the association between circulating levels of Hsp27 and different types of periodontitis. Pro- and anti-inflammatory cytokines and the stress proteins Hsp27 and Hsp60 with proposed anti- and pro-inflammatory properties, respectively, were measured by two-site ELISA in the serum of patients with aggressive periodontitis (AgP, n = 30), chronic periodontitis (CP, n = 29) and periodontally healthy controls (H, n = 28). Furthermore, Hsp27 and Hsp60 levels were also measured longitudinally in 12 AgP patients at 6 time points up to 3 months after treatment. AgP patients had lower levels of Hsp27 compared to CP patients and healthy subjects (adjusted one-way ANOVA, p < 0.001, followed by post hoc Tukey HSD comparisons), while no differences in levels of Hsp60 or cytokines between the three groups were detected. In CP patients and H subjects, the systemic Hsp27 levels correlated with Hsp60 (r = 0.43, p < 0.001; r = 0.59, p < 0.001, respectively) and with pro-inflammatory cytokines TNF-α (r = 0.48, p < 0.001; r = 0.55, p < 0.001, respectively) and IL-6 (r = 0.44, p < 0.01). However, no such correlations were detected in AgP cases. No consistent temporal patterns of changes of Hsp27 concentration were detected across AgP patients following periodontal treatment. This study provides the first evidence that Hsp27 may be differentially expressed and regulated in AgP patients as compared with CP patients and healthy individuals.

Differential Diagnosis between Chronic versus Aggressive Periodontitis and Staging of Aggressive Periodontitis: A Cross-sectional Study

Background

Differentiating between chronic periodontitis (CP) and aggressive periodontitis (AgP) is challenging. The aim of this study was to assess the variations in diagnosis between CP versus AgP and the staging of AgP based on the disease-staging index for AgP among periodontists, specialists in oral medicine, and general dental practitioners (GDPs).

Materials and Methods

Fifteen cases diagnosed as either CP or AgP were included in a "case document" and sent electronically to 75 respondents. Case document included a detailed history with periodontal charting, clinical features, images, and radiographs for all the cases. Diagnosis and staging for the case (if diagnosed as AgP) were requested. A reordered case document (cases in a different sequence) was again sent to respondents after a gap of 1 month.

Statistical analysis

Descriptive statistics including frequency and percentage were calculated. Pearson's Chi-square test was used to analyze the data collected.

Results

For the "case document," 10.17% of the responses were different from those of the authors for diagnosis, whereas 4.48% of the responses were different from those of the authors for the staging of AgP. The agreement in the overall responses was in the range of 0.69-0.84, which was considered good. Comparison of the responses for diagnosis showed statistically significant (P = 0.009) difference between specialists in oral medicine and GDPs.

Conclusions

Variations exist among respondents regarding the diagnosis of CP versus AgP. Staging of AgP based on the listed criteria showed low variations.

Microbial colonization of the periodontal pocket and its significance for periodontal therapy

The aim of this paper was to evaluate strategies for periodontal therapy from the perspective of periodontal disease being a consequence of microbial colonization of the periodontal pocket environment. In classic bacterial infections the diversity of the microbiota decreases as the disease develops. In most cases of periodontitis, however, the diversity of the flora increases. Most incriminating bacteria are thought to harm tissues significantly only if present in high numbers over prolonged periods of time. Clinical trials have repeatedly demonstrated that scaling and root planing, a procedure that aims to remove subgingival bacterial deposits by scraping on the tooth surface within the periodontal pocket, is effective. At present, for the therapy of any form of periodontal disease, there exists no protocol with proven superiority, in terms of efficiency or effectiveness, over scaling and root planing plus systemic amoxicillin and metronidazole. Some exponents advocate rationing these drugs for patients with a specific microbial profile. However, the evidence for any benefit of bacteriology-assisted clinical protocols is unsatisfactory. Treated sites are subject to recolonization with a microbiota similar to that present before therapy. The degree and speed of recolonization depends on the treatment protocol, the distribution patterns of periodontal microorganisms elsewhere in the oral cavity and the quality of the patient's oral hygiene. To limit the use of antibiotics and to avoid accumulation of harmful effects by repeated therapy, further efforts must be made to optimize procedures addressing the microbial colonization and recolonization of the periodontal pocket.

Effect of photodynamic therapy adjunct to scaling and root planing in periodontitis patients: A randomized clinical trial

BACKGROUND

A randomized split-mouth controlled clinical trial was conducted to evaluate the efficacy of photodynamic therapy (PDT) in reducing Aggregatibacter actinomycetemcomitans (Aa) in periodontitis patients.

METHODS

Twenty patients with periodontitis were recruited for the trial. Following random allocation of either quadrants of the selected jaw to test or control treatment, conventional non-surgical periodontal therapy (NSPT) was performed. In addition, the test side received adjunct photodynamic therapy. Probing depth (PD), clinical attachment level, bleeding on probing (BoP) and plaque scores (PS%) were recorded at phase 0 (baseline), phase 1 (immediately after NSPT), phase 2 (7 days following NSPT), phase 3 (1 month following NSPT) and phase 4 (3 months following NSPT). Subgingival plaque samples for quantification of Aa by real-time polymerase chain reaction was performed at phases 0, 1, 2 and 4.

RESULTS

There was a significant clinical improvement at phases 3 and 4 compared with baseline while BoP reduced significantly only in the test group at phase 4. However, no difference in the quantification of Aa was detected between the groups.

CONCLUSIONS

Within the limits of the study, PDT adjunct to scaling and root planing does not lead to quantitative reduction of Aa in periodontitis patients.

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.

Periodontal Surgery Involving Modified Widman Flap Procedure and Connective Tissue Graft for Generalized Aggressive Periodontitis: A Case Report

We report a case of generalized aggressive periodontitis (AgP) requiring periodontal treatment including flap surgery and ridge augmentation. The patient was a 39-year-old woman who presented with the chief complaint of pus discharge from tooth #36. No other obvious signs of gingival inflammation were observed. Periodontal examination revealed multiple sites with a probing depth of ≥10 mm. Radiography showed pro-nounced bone defects in the maxillary incisors and molar region. Real-time PCR was used to detect Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia in subgingival plaque; all 3 pathogens were found. Based on a clinical diagnosis of generalized AgP, periodontal therapy was initiated, which resulted in an improvement in clinical and microbiological parameters. A modified Widman flap procedure was then performed on sites with residual periodontal pockets. Next, a connective tissue graft was performed for ridge augmentation at #22, which had shown evidence of ridge resorption. Postoperative reevaluation revealed a reduction in probing depth and an improvement in marginal bone levels. Oral function was then restored using a fixed bridge prosthesis and maintenance therapy initiated. The periodontal condition has remained stable over a 2.5-year period. In the present case of AgP, surgical intervention reduced periodontal pockets and periodontal pathogens and improved the architecture of both the hard and soft tissues, allowing subsequent care of the periodontium to be performed efficiently by the patient.

Effect of patient age awareness on diagnostic agreement of chronic or aggressive periodontitis between clinicians; a pilot study

BACKGROUND

The aim of this pilot study was to test whether diagnostic agreement of aggressive and chronic periodontitis amongst Board Certified Periodontists, is influenced by knowledge of a patient's age. In 1999 at the International World Workshop age was removed as a diagnostic criteria for aggressive periodontitis. The impact of this change on the diagnostic reliability amongst clinicians has not yet been assessed.

METHODS

Nine periodontal case reports were twice presented to sixteen board certified periodontists, once with age withheld and again with patient age provided. Participants were instructed to choose a diagnosis of Chronic Periodontitis or Aggressive Periodontitis. Diagnostic agreement was calculated using the Fleiss Kappa test.

RESULTS

Including the patients' age in case report information increased diagnostic agreement (the kappa statistic) from 0.49 (moderate agreement) to 0.61 (substantial agreement).

CONCLUSION

These results suggest that knowledge of a patients' age influenced clinical diagnosis, when distinguishing between aggressive periodontitis and chronic periodontitis, which may in turn impact treatment decision-making.

Relationship between invasion of the periodontium by periodontal pathogens and periodontal disease: a systematic review

Bacterial invasion of the periodontal tissues has been suggested as a relevant step in the etiopathogenesis of periodontal disease. However, its exact importance remains to be defined. The present systematic review assessed the scientific evidence concerning the relationship between the quality or quantity of periodontal microbiota in periodontal tissues and development of periodontal disease. The databases Medline-PubMed, Cochrane-CENTRAL, ISI Web of Knowledge and SCOPUS were searched, up to January 2014. Studies that reported evaluation of periodontal pathogens invasion on human tissues were selected. The screening of 440 title/abstracts elected 26 papers for full-text reading. Twenty three papers were subsequently excluded because of insufficient data or a study protocol not related to the objectives of this systematic review. All included studies were case-control studies that evaluated intracellular or adherent bacteria to epithelial cells from periodontal pockets versus healthy sulci. Study protocols presented heterogeneity regarding case and control definitions and methodological approaches for microbial identification. No consistent significant differences were found related to the presence/absence or proportion of specific periopathogens across the studies, as only one study found statistically significant differences regarding the presence of A. actinomycetemcomitans (p = 0.043), T. forsythia (P < 0.001), P. intermedia (P < 0.001), C. ochracea (P < 0.001) and C. rectus (P = 0.003) in epithelial cells from periodontal pockets vs. healthy sulci. All studies reported a larger unspecific bacterial load in or on the epithelial cells taken from a diseased site compared to a healthy sulcus. The current available data is of low to moderate quality and inconsistent mainly due to study design, poor reporting and methodological diversity. As so, there is insufficient evidence to support or exclude the invasion by periodontal pathogens as a key step in the etiopathogenesis of periodontal disease. Further research is needed.

Comparative analysis of blood and saliva expression profiles in chronic and refractory periodontitis patients

Background

This study aimed to identify characteristic representative genes through a comparative analysis of gene expression profiles in the blood and saliva of chronic periodontitis (CP) and refractory periodontitis (RP) patients to provide new treatment strategies that may be helpful in the treatment of different forms of periodontitis.

Methods

GSE43525 was downloaded from Gene Expression Omnibus. In the dataset, thirteen samples were from blood including 4 controls, 4 CP and 5 RP samples, and ten samples were from saliva including 3 controls, 4 CP and 3 RP samples. After comparing the CP and RP samples, differentially expressed genes (DEGs) between these two types of periodontitis in the blood and saliva samples were identified by an LIMMA package. Then, functional and pathway enrichment analyses were performed by DAVID and KOBAS, respectively. The significantly associated miRNAs in CP and RP were searched by WebGestalt.

Results

In total, 213 DEGs in CP and 45 DEGs in RP were identified. Functional enrichment showed that the DEGs of CP were mainly enriched in ribosome and regulation of apoptosis-related pathways in blood as well as saliva, while the DEGs of RP were significantly enriched in immune responses and response to organic substance-related pathways. Several miRNAs, such as miR-381 and miR-494, were identified as being closely associated with CP. In addition, CD24, EST1, MTSS1, ING3, CCND2 and SYNE2 might be potential targets for diagnosis and treatment of CP.

Conclusion

The identified DEGs and miRNAs might be potential targets for the treatment of chronic and refractory periodontitis.

Host response mechanisms in periodontal diseases

Periodontal diseases usually refer to common inflammatory disorders known as gingivitis and periodontitis, which are caused by a pathogenic microbiota in the subgingival biofilm, including Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola that trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth, and eventually in tissue, bone and finally, tooth loss. The innate immune response constitutes a homeostatic system, which is the first line of defense, and is able to recognize invading microorganisms as non-self, triggering immune responses to eliminate them. In addition to the innate immunity, adaptive immunity cells and characteristic cytokines have been described as important players in the periodontal disease pathogenesis scenario, with a special attention to CD4⁺ T-cells (T-helper cells). Interestingly, the T cell-mediated adaptive immunity development is highly dependent on innate immunity-associated antigen presenting cells, which after antigen capture undergo into a maturation process and migrate towards the lymph nodes, where they produce distinct patterns of cytokines that will contribute to the subsequent polarization and activation of specific T CD4+ lymphocytes. Skeletal homeostasis depends on a dynamic balance between the activities of the bone-forming osteoblasts (OBLs) and bone-resorbing osteoclasts (OCLs). This balance is tightly controlled by various regulatory systems, such as the endocrine system, and is influenced by the immune system, an osteoimmunological regulation depending on lymphocyte- and macrophage-derived cytokines. All these cytokines and inflammatory mediators are capable of acting alone or in concert, to stimulate periodontal breakdown and collagen destruction via tissue-derived matrix metalloproteinases, a characterization of the progression of periodontitis as a stage that presents a significantly host immune and inflammatory response to the microbial challenge that determine of susceptibility to develop the destructive/progressive periodontitis under the influence of multiple behavioral, environmental and genetic factors.

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.

Oral Microbiota, Periodontal Status, and Osteoporosis in Postmenopausal Females

BACKGROUND

Alterations in hormone levels during menopause decrease bone density and may worsen oral health, favoring the growth of periodontal pathogens, whose detection could improve the diagnosis of periodontitis. The aim of this study is to detect and quantify the main periodontal pathogens in the oral microbiota of postmenopausal females and to explore the relationship between clinical and periodontal parameters.

METHODS

This was an observational cross-sectional study of 76 postmenopausal females. Dental examinations and sampling for microbiologic evaluation were performed, and a history of osteoporosis/osteopenia was collected. Real-time polymerase chain reaction was used for detecting and quantifying Fusobacterium nucleatum (Fn), Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Campylobacter rectus (Cr), and Tannerella forsythia (Tf). The results obtained were subjected to statistical analyses. Statistical significance was defined as P <0.05.

RESULTS

Periodontitis was detected in 77.1% of females with osteoporosis/osteopenia (P >0.05). A significant correlation was found between osteoporosis and missing teeth. T. forsythia and C. rectus were detected in 100% of the samples, Fn and Pg in 98.7%, and Aa in 73.7%.

CONCLUSIONS

Osteoporosis did not influence the prevalence of periodontitis among postmenopausal females. The presence of periodontopathogenic bacteria was not sufficient to confirm disease. A preventive maintenance program for postmenopausal females, particularly osteoporotic females, who are at greater risk of tooth loss, could minimize the potential effects of bone loss on periodontal tissues.

Aggregatibacter actinomycetemcomitans serotypes and DGGE subtypes in Thai adults with chronic periodontitis

OBJECTIVE

To investigate the distribution of Aggregatibacter actinomycetemcomitans serotypes and DGGE subtypes among isolates from Thai chronic periodontitis patients.

DESIGN

Forty-four adult Thai periodontitis patients were assessed by a full mouth recording for CAL, PPD, and BOP. Seventy-nine strains of A. actinomycetemcomitans were isolated from deep pockets on selective TSBV agar and 17 strains were isolated from shallow pockets. The strains were serotyped using PCR and subtyped using DGGE.

RESULTS

The prevalence of A. actinomycetemcomitans was 84.1%. Non-serotypeable A. actinomycetemcomitans strains occurred equally frequent as serotypeable (54.5%); serotype a 18.2%, serotype c 15.9%, serotype e 9.1%, and serotype f 11.4%. Serotype b and d were not detected. A JP2 like strain but serotyped as c was isolated from two patients, and another two strains showed an 886bp insertion on the ltx promoter of their A. actinomycetemcomitans isolates. DGGE typing disclosed 16 different subtypes among the non-serotypeable strains. Two of them (NS1 and NS2) were more common (12.7 and 10.1%) among the strains than the other 14 subtypes (˂5.1%). Most patients showed only one subtype (32.4%) but 29.7% had 2 and 3 different subtypes while 8.1% revealed 4 subtypes in one and the same deep pocket.

CONCLUSION

This study showed a greater subtype diversity of A. actinomycetemcomitans predominated by non-serotypeable strains than previously reported in an adult Thai population. It was also revealed for the first time that isolates with a 530bp deletion or 886bp insertion of the ltx promoter were serotyped as serotype c.

Deoxyribonucleic Acid Probes Analyses for the Detection of Periodontal Pathogens

BACKGROUND

In clinical microbiology several techniques have been used to identify bacteria. Recently, Deoxyribonucleic acid (DNA)-based techniques have been introduced to detect human microbial pathogens in periodontal diseases. Deoxyribonucleic acid probes can detect bacteria at a very low level if we compared with the culture methods. These probes have shown rapid and cost-effective microbial diagnosis, good sensitivity and specificity for some periodontal pathogens in cases of severe periodontitis.

MATERIALS AND METHODS

Eighty-five patients were recruited for the study. Twenty-one subjects ranging between 22 and 48 years of age fulfilled the inclusion and exclusion criteria. Seventy-eight samples became available for DNA probe analysis from the deepest pockets in each quadrant.

RESULTS

All 21 patients showed positive results for Prevotella intermedia; also, Prevotella gingivalis was identified in 19 subjects, Aggregatibacter actinomycetemcomitans in 6 subjects. P. intermedia was diagnosed positive in 82% of the subgingival samples taken, 79% for P. gingivalis, and 23% for A. actinomycetemcomitans.

CONCLUSION

This study shows a high frequency of putative periodontal pathogens by using DNA probe technology, which is semi-quantitative in this study. Deoxyribonucleic acid probes can detect bacteria at very low level about 10(3) which is below the detection level of culture methods. The detection threshold of cultural methods.

CLINICAL SIGNIFICANCE

The three types of bacteria can be detected rapidly with high sensitivity by using the DNA probe by general practitioners, and thus can help in the diagnosis process and the treatment.

Detection of subgingival periodontal pathogens--comparison of two sampling strategies

OBJECTIVE

The aim of the study is to compare detection frequency of periodontal pathogens in patients with aggressive/severe chronic periodontitis using pooled plaque samples from the deepest pockets per quadrant/per sextant.

METHODS

In 100 patients with aggressive/chronic periodontitis, subgingival plaque was sampled from the deepest pockets per quadrant (MT4) and per sextant (MT6). Plaque samples were taken using two sterile paper points simultaneously. One paper point from each pocket was pooled with the three other paper points of the pockets (MT4). Subsequently, the remaining four paper points were pooled with two paper points from the deepest pockets from the two remaining sextants (MT6). The content of each vial was analyzed with nucleic-acid based methods for Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Parvimonas micra, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens, and Capnocytophaga sp.

RESULTS

The detection frequency of A. actinomycetemcomitans (MT4/MT6) at 22/24 %, T. forsythia at 93/96 %, P. gingivalis at 78/79 %, T. denticola at 88/90 %, P. intermedia at 40/46 %, P. micra at 75/79 %, F. nucleatum at both 99 %, C. rectus at 84/89 %, E. nodatum at 62/65 %, E. corrodens at 80/87 %, and Capnocytophaga sp. at 49/58 % was higher with MT6 than with MT4. None of these differences were statistically significant.

CONCLUSION

The detection frequency of the investigated periopathogens was statistically insignificant higher with the sampling method MT6 compared with MT4.

CLINICAL RELEVANCE

In daily dental practice, the plaque sampling of the deepest pockets per quadrant seems to be sufficient.

Periodontal progression based on radiographic records: An observational study in chronic and aggressive periodontitis

OBJECTIVES

The current classification assumes that aggressive periodontitis (AgP) has a faster rate of progression than chronic periodontitis (CP). However, this has not been clearly proven and difficulties exist in establishing progression. This study aimed to assess the feasibility of retrospectively utilising previous records for clinical diagnosis of periodontal diseases and to assess if two different patterns of disease progression exist between AgP and CP.

MATERIALS AND METHODS

Previous radiographic records of a cohort of 235 patients clinically diagnosed with AgP or CP were requested from the referring general dental practitioners (GDPs). Comparable radiographic records were analysed in order to assess progression patterns and associate these with clinical diagnosis, by multilevel analysis.

RESULTS

43 patients out of the initial 235 had comparable radiographs retrieved from the GDPs. 858 sites were followed for an average 6.6 years. Radiographically, AgP showed a faster linear pattern of progression than CP (0.31mm/year vs. 0.20mm/year, p<0.001).

CONCLUSION

This study provides evidence for a faster disease progression in untreated AgP compared to CP as assessed by radiographic bone levels. Furthermore, it shows that retrievability of previous radiographs from GDPs is unpredictable and GDPs should be encouraged to send them along with their referral.

CLINICAL SIGNIFICANCE

The importance of differentially diagnosing AgP and CP might be useful in establishing a clinically relevant definition for periodontal disease progression and may have an impact on the clinical management of aggressive periodontitis, since our findings show that there is continuous destruction in patients with aggressive periodontitis if left untreated.

Bacterial profile of aggressive periodontitis in Morocco: a cross-sectional study

Background

Aggressive periodontitis (AgP) is one of the most severe forms of periodontal diseases. In Morocco, Aggregatibacter actinomycetemcomitans has been strongly associated with AgP, however limited knowledge is available about the implication of other periodontal pathogens in this entity. Therefore, the main aim of this study was to evaluate the composition of the subgingival microbiota in Moroccan patients with AgP.

Methods

Subgingival plaque samples were collected from 50 aggressive, 13 localized and 37 generalized periodontitis patients. Samples from 20 chronic periodontitis (ChP) patients were taken as controls. Samples collected from the four deepest periodontal pockets in each patient were pooled in pre-reduced transport fluid and examined by culture.

Results

A. actinomycetemcomitans was significantly more frequent (p = 0.004) in generalised AgP compared to ChP, and Porphyromonas gingivalis was less prevalent in localized AgP, when compared with generalized AgP (p = 0.040) or ChP (p = 0.016). Prevotella intermedia, Fusobacterium nucleatum and Tannerella forsythia were also frequently detected in all groups. Mean proportions of A. actinomycetemcomitans were significantly higher in AgP groups, when compared to ChP, and generalized AgP patients harbored significantly higher proportions of P. gingivalis and T. forsythia, when compared to localized AgP or ChP.

Conclusions

A. actinomycetemcomitans, P. gingivalis, T. forsythia, P. intermedia and F. nucleatum were frequently detected in this Moroccan population with AgP. Differences in frequency of detection, counts and proportions of A. actinomycetemcomitans, P. gingivalis and T. forsythia suggests the presence of distinct microbiological profiles for localized AgP, generalized AgP and ChP patients.

Differential benefits of amoxicillin-metronidazole in different phases of periodontal therapy in a randomized controlled crossover clinical trial

BACKGROUND

The specific advantage of administering systemic antibiotics during initial, non-surgical therapy or in the context of periodontal surgery is unclear. This study assesses the differential outcomes of periodontal therapy supplemented with amoxicillin-metronidazole during either the non-surgical or the surgical treatment phase.

METHODS

This is a single-center, randomized placebo-controlled crossover clinical trial with a 1-year follow-up. Eighty participants with Aggregatibacter actinomycetemcomitans-associated moderate to advanced periodontitis were randomized into two treatment groups: group A, antibiotics (500 mg metronidazole plus 375 mg amoxicillin three times per day for 7 days) during the first, non-surgical phase of periodontal therapy (T1) and placebo during the second, surgical phase (T2); and group B, placebo during T1 and antibiotics during T2. The number of sites with probing depth (PD) >4 mm and bleeding on probing (BOP) per patient was the primary outcome.

RESULTS

A total of 11,212 sites were clinically monitored on 1,870 teeth. T1 with antibiotics decreased the number of sites with PD >4 mm and BOP per patient significantly more than without (group A: from 34.5 to 5.7, 84%; group B: from 28.7 to 8.7, 70%; P <0.01). Twenty patients treated with antibiotics, but only eight treated with placebo, achieved a 10-fold reduction of diseased sites (P = 0.007). Consequently, fewer patients of group A needed additional therapy, the mean number of surgical interventions was lower, and treatment time in T2 was shorter. Six months after T2, the mean number of residual pockets (group A: 2.8 ± 5.2; group B: 2.2 ± 5.0) was not significantly different and was sustained over 12 months in both groups.

CONCLUSION

Giving the antibiotics during T1 or T2 yielded similar long-term outcomes, but antibiotics in T1 resolved the disease quicker and thus reduced the need for additional surgical intervention.

General immune status and oral microbiology in patients with different forms of periodontitis and healthy control subjects

Objective

Immunological processes in the etiopathogenesis of periodontitis, especially the aggressive form, are not well understood. This study examined clinical as well as systemic immunological and local microbiological features in healthy controls and patients with different forms of periodontitis.

Materials and Methods

14 healthy subjects, 15 patients diagnosed with aggressive periodontitis, and 11 patients with chronic periodontitis were recruited. Periodontal examination was performed and peripheral blood was collected from each patient. Lymphocyte populations as well as the release of cytokines by T-helper cells were determined by flow cytometry and enzyme linked immunosorbent spot assay. Subgingival plaque samples were taken from each individual and immediately cultivated for microbiological examination.

Results

When stimulating peripheral blood mononuclear cells (PBMCs) with lipopolysaccharide, a higher IL-1β release was found in patients with moderate chronic periodontitis compared to the other groups (p<0.01). Numbers of B-cells, naïve and transitional B-cells, memory B-cells, and switched memory B-cells were within the reference range for all groups, but patients with chronic periodontitis showed the highest percentage of memory B-cells without class switch (p = 0.01). The subgingival plaque differed quantitatively as well as qualitatively with a higher number of Gram-negative anaerobic species in periodontitis patients. Prevotella denticola was found more often in patients with aggressive periodontitis (p<0.001) but did not show an association to any of the systemic immunological findings. Porphyromonas gingivalis, which was only found in patients with moderate chronic periodontitis, seems to be associated with an activation of the systemic immune response.

Conclusion

Differences between aggressive periodontitis and moderate chronic periodontitis are evident, which raises the question of an inadequate balance between systemic immune response and bacterial infection in aggressive periodontitis.

Periodontal pathogens and associated factors in aggressive periodontitis: results 5-17 years after active periodontal therapy

OBJECTIVES

To assess the association between presence of periodontal pathogens and recurrence of disease in patients with aggressive periodontitis (AgP) after active periodontal therapy (APT) and further influencing factors.

MATERIAL & METHODS

Microbiological samples were taken from 73 patients with AgP 5-17 years after APT at 292 sites (deepest site per quadrant). Real-time polymerase chain reactions were used to detect the periodontal pathogens Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola. Uni- and multivariate analyses evaluated the associations between pathogens and recurrence of disease, smoking and adjunctive antibiotic therapy.

RESULTS

At re-examination A. actinomycetemcomitans could be detected in six patients (8.2%), P. gingivalis in 24 (32.9%), T. forsythia in 31 (42.5%) and T. denticola in 35 (48.0%). Increased levels of T. forsythia and T. denticola at re-examination were significantly associated with recurrence of disease in multivariate analyses (OR: 12.72, p < 0.001; OR 5.55, p = 0.002 respectively). Furthermore, high counts of T. denticola were found in patients with increased percentage of sites with clinical attachment levels (CAL) ≥ 6 mm compared to those with low counts (13.8% versus 3.2%, p = 0.005).

CONCLUSION

In patients with recurrence of disease T. forsythia and T. denticola were detected more frequently and in higher counts. Furthermore, T. denticola was found more frequently in patients with increased CAL.

Analysis of periodontal attachment loss in relation to root form abnormalities

Purpose

The aim of this study was to explore root shape abnormalities, to investigate the influence of root form abnormalities on periodontal attachment loss, and to gather basic data to assist in the diagnosis and treatment of aggressive periodontitis.

Methods

From January 2010 to June 2012, a survey was conducted of all 3,284 periodontitis patients who visited the Department of Periodontology, Daejeon Dental Hospital, Wonkwang University School of Dentistry. Clinical parameters (probing depth, periodontal attachment loss, missing teeth) were measured and a radiographic examination was performed at the baseline. We classified the root shape abnormality of bicuspids and molars based on Meng classification.

Results

The periodontal attachment loss was the highest at the maxillary first molar (6.03 mm). The loss of the second molar was prominent. Type V deformity was shown to be the most common in the second maxillary and mandibular molars (P<0.05). Type V root shape was associated with the highest attachment loss (P=0.01).

Conclusions

Considering the small population and limited design of this study, definitive conclusions cannot be drawn. We suggest larger scale, methodologically more sophisticated studies that include normal controls and chronic periodontitis patients to clarify whether root form abnormalities are a potential risk factor for aggressive periodontitis.

Correlation of Aggregatibacter actinomycetemcomitans detection with clinical/immunoinflammatory profile of localized aggressive periodontitis using a 16S rRNA microarray method: a cross-sectional study

OBJECTIVE

The objective of this study was to determine whether the detection of Aggregatibacter actinomycetemcomitans (Aa) correlates with the clinical and immunoinflammatory profile of Localized Aggressive Periodontitis (LAP), as determined by by 16S rRNA gene-based microarray.

SUBJECTS AND METHODS

Subgingival plaque samples from the deepest diseased site of 30 LAP patients [PD ≥ 5 mm, BoP and bone loss] were analyzed by 16S rRNA gene-based microarrays. Gingival crevicular fluid (GCF) samples were analyzed for 14 cyto/chemokines. Peripheral blood was obtained and stimulated in vitro with P.gingivalis and E.coli to evaluate inflammatory response profiles. Plasma lipopolysaccharide (LPS) levels were also measured.

RESULTS

Aa was detected in 56% of LAP patients and was shown to be an indicator for different bacterial community structures (p<0.01). Elevated levels of pro-inflammatory cyto/chemokines were detected in LPS-stimulated blood samples in both Aa-detected and Aa-non-detected groups (p>0.05). Clinical parameters and serum LPS levels were similar between groups. However, Aa-non-detected GCF contained higher concentration of IL-8 than Aa-detected sites (p<0.05). TNFα and IL1β were elevated upon E.coli LPS stimulation of peripheral blood cells derived from patients with Aa-detected sites.

CONCLUSIONS

Our findings demonstrate that the detection of Aa in LAP affected sites, did not correlate with clinical severity of the disease at the time of sampling in this cross-sectional study, although it did associate with lower local levels of IL-8, a different subgingival bacterial profile and elevated LPS-induced levels of TNFα and IL1β.

Haplotype analysis of interleukin-8 gene polymorphisms in chronic and aggressive periodontitis

Objectives. Periodontitis is an inflammatory disease characterized by connective tissue loss and alveolar bone destruction. Interleukin-8 (IL8) is important in the regulation of the immune response. The aim of this study was to analyze four polymorphisms in the IL8 gene in relation to chronic (CP) and aggressive (AgP) periodontitis. Methods. A total of 492 unrelated subjects were included in this case-control association study. Genomic DNA of 278 patients with CP, 58 patients with AgP, and 156 controls were genotyped, using the 5′ nuclease TaqMan assay, for IL8 (rs4073, rs2227307, rs2227306, and rs2227532) gene polymorphisms. Subgingival bacterial colonization was investigated by the DNA-microarray detection kit in a subgroup of subjects (N = 247). Results. Allele and genotype frequencies of all investigated IL8 polymorphisms were not significantly different between the subjects with CP and/or AgP and controls (P > 0.05). Nevertheless, the A(−251)/T(+396)/T(+781) and T(−251)/G(+396)/C(+781) haplotypes were significantly less frequent in patients with CP (2.0% versus 5.1%, P < 0.02, OR = 0.34, 95% CI: 0.15–0.78, resp., 2.0% versus 4.5%, P < 0.05, OR = 0.41, 95% CI: 0.18–0.97) than in controls. Conclusions. Although none of the investigated SNPs in the IL8 gene was individually associated with periodontitis, some haplotypes can be protective against CP in the Czech population.