Classification of periodontal diseases

Necrotizing Gingivitis: Microbial Diversity and Quantification of Protein Secretion in Necrotizing Gingivitis

Necrotizing gingivitis (NG) is a necrotizing periodontal disease that differs from chronic gingivitis (CG). To date, both the microbiological causes and the involved host cytokine response of NG still remain unclear. Here, we investigated corresponding interdental plaque and serum samples from two groups of Chinese patients with CG (n = 21) or NG (n = 21). The microbiota were studied by 16S rRNA Illumina MiSeq sequencing of the microbial metagenome and by assessing quantitatively the abundance of the phylum Bacteroidetes, the genus Prevotella and the species T. forsythia, P. endodontalis, and P. gingivalis using fluorescence in situ hybridization (FISH). With respect to the associated host response, the levels of 30 inflammatory mediators were quantified by multiplex immunoassay analysis. Differential microbial abundance analysis of the two disease groups revealed at the phylum level that Proteobacteria accounted for 67% of the differentially abundant organisms, followed by organisms of Firmicutes (21%) and Actinobacteria (9%). At the species level, significant differences in abundance were seen for 75 species of which 58 species were significantly more abundant in CG patients. Notably, the FISH analysis revealed that Bacteroidetes was the most prevalent phylum in NG. The multiplex cytokine assay showed significant quantitative differences between the disease groups for eight analytes (GM–CSF, G–CSF, IFN–α, IL–4, IL–13, TNF–α, MIG, and HGF). The G–CSF was found to be the most significantly increased inflammatory protein marker in NG. The next-generation sequencing (NGS) data supported the understanding of NG as a multi-microbial infection with distinct differences to CG in regard to the microbial composition.

Are there correlations between radiographic grade levels and modified grade levels of periodontitis?

BACKGROUND

At the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions, periodontitis was reclassified according to a multidimensional staging and grading system. Grading takes variabilities in the rate of disease progression into account, relying on recognized progression risk factors, and is based on the assessment of bone loss at the worst-affected tooth in the dentition as a function of age, which is then modified by factors such as smoking and diabetes mellitus. In this context, the aim of this study was to determine whether there are correlations between radiographically calculated grades and grades modified by the presence of smoking or diabetes.

MATERIALS AND METHODS

In this descriptive study, individuals diagnosed with periodontitis according to the 2017 classifications were examined. The grade of periodontitis was measured using periapical radiography. A modified-grade level was assigned to the patients according to their glycated hemoglobin levels (in diabetics) or their smoking status.

RESULTS

The study included 341 individuals. No statistically significant relationship was revealed by Chi-square testing (P > 0.05) or in the kappa agreement index between the modified grades and the radiographic grades.

CONCLUSIONS

Although there was no correlation between radiographic grade and modified grade in smokers and diabetic individuals, increasing the grade score in these individuals in accordance with the 2017 classification provides clinicians the opportunity to develop a risk-based treatment plan, commensurate with the severity of periodontal disease and the level of risk.

[Insights into peri-implantitis and its prevention]

Peri-implantitis is one of the most common complications in dental implant treatment. Peri-implantitis is a crucial implication of implant failure, which is characterized by high morbidity and intractability. Thus, how to understand peri-implantitis correctly and deeply, and how to prevent its occurrence, are important problems that every dental implant surgeon has to face.

Microbial biogeography and ecology of the mouth and implications for periodontal diseases

In humans, the composition of microbial communities differs among body sites and between habitats within a single site. Patterns of variation in the distribution of organisms across time and space are referred to as "biogeography." The human oral cavity is a critical observatory for exploring microbial biogeography because it is spatially structured, easily accessible, and its microbiota has been linked to the promotion of both health and disease. The biogeographic features of microbial communities residing in spatially distinct, but ecologically similar, environments on the human body, including the subgingival crevice, have not yet been adequately explored. The purpose of this paper is twofold. First, we seek to provide the dental community with a primer on biogeographic theory, highlighting its relevance to the study of the human oral cavity. We summarize what is known about the biogeographic variation of dental caries and periodontitis and postulate that disease occurrence reflects spatial patterning in the composition and structure of oral microbial communities. Second, we present a number of methods that investigators can use to test specific hypotheses using biogeographic theory. To anchor our discussion, we apply each method to a case study and examine the spatial variation of the human subgingival microbiota in 2 individuals. Our case study suggests that the composition of subgingival communities may conform to an anterior-to-posterior gradient within the oral cavity. The gradient appears to be structured by both deterministic and nondeterministic processes, although additional work is needed to confirm these findings. A better understanding of biogeographic patterns and processes will lead to improved efficacy of dental interventions targeting the oral microbiota.

Plasminogen activator inhibitor-1 polymorphisms as a risk factor for chronic periodontitis in North Indian population

Objectives

Impaired plasminogen activator inhibitor-1 (PAI-1), controlling coagulation and the fibrinolytic system is supposed to be involved in the pathogenesis of periodontitis. This study was performed to examine the association of PAI-1 gene polymorphisms with Chronic Periodontitis (CP) and alveolar bone loss severity involved with the disease and for understanding the role of genetic contributions in disease progression.

Methods

87 volunteers were included in the study. Genomic DNA was isolated from peripheral blood, subsequently, DNA samples were subjected to polymerase chain reaction and endonuclease digestion. Direct gene sequencing were performed for all the samples to identify genotype polymorphisms (rs 11560324) in the 3' untranslated region of PAI-1 gene. For bone loss assessment full mouth IOPA was taken.

Results

Statistical analysis showed that for SNP PAI-I in 3' UTR, genotype CC (homozygous mutant) and allele C (mutant) has a risk associated with CP, although statistically significant association was not found. An increased risk of association of disease severity with CG (heterozygous mutant) and CC (homozygous mutant) genotypes, i.e., an increased carriage rate of genotype CG and CC (homozygous mutant) was evident with the increase in the severity of CP, highlighting an increased susceptibility to CP due to this gene polymorphisms.

Conclusion

PAI-1 genotype has a risk association with CP and alveolar bone loss severity in North-Indian population.

The microbial community shifts of subgingival plaque in patients with generalized aggressive periodontitis following non-surgical periodontal therapy: a pilot study

The object of this study is to characterize the bacterial community of subgingival plaque of two subjects with generalized aggressive periodontitis (GAgP) pre- and post-treatment. We picked two patients with GAgP and used high-throughput 16S rDNA sequencing. V4 hypervariable region was picked for PCR amplification of subgingival samples. Then, the PCR products were sequenced through Illumina MiSeq platform. One month after therapy, both the clinical features and periodontal parameters improved obviously. Moreover, the composition and structure of subgingival bacterial community changed after initial periodontal therapy. Also, the composition of the subgingival microbiota was highly individualized among different patients. Bacteroidetes, Spirochaetes and Fusobacteria were related to pathogenicity of GAgP while Actinobacteria and Proteobacteria seemed associated with clinical symptoms resolution. In this study, we found the subgingival bacterial community was high in species richness but dominated by a few species or phylotypes, with significant shifts of microbiota that occurred after treatment. This study demonstrated the shift of the subgingival bacterial community before and after treatment by high-throughput 16S rDNA sequencing, and provided a concise method for analysis of microbial community for periodontal diseases.

Comparative Analysis of Salivary Alkaline Phosphatase in Post menopausal Women with and without Periodontitis

INTRODUCTION

Alkaline phosphatase is an intracellular destruction enzyme in the periodontium, and it takes part in the normal turnover of the periodontal ligament, alveolar bone, and root cementum formation and maintenance.

AIM

The aim of this case control study was to evaluate the enzyme Alkaline Phosphatase (ALP) level in saliva of post menopausal women with and without chronic periodontitis.

MATERIALS AND METHODS

In this study, 40 individuals, satisfying the study inclusion and exclusion criteria, were recruited. They were categorically divided, on the basis of gingival index, probing pocket depth and clinical attachment level, into two groups: Group I (post menopausal women with a clinically healthy periodontium, n=20); and Group II (post menopausal women with generalized chronic periodontitis, n=20). Clinical parameters assessed were Plaque Index (PI), Gingival Index (GI), Clinical Attachment Level (CAL) and Probing Pocket Depth (PPD). Unstimulated salivary samples were obtained in which the ALP concentration was measured using p-Nitrophenylphosphate, and 2-amino-2-methyl-1-propanol reagents in Beckman and Coulter, AU 480 auto analyser. Mann-Whitney U test was used to find statistical difference with respect to all clinical parameters such as PI, GI, CAL, PPD and salivary ALP levels.

RESULTS

The mean ALP in saliva was found to be higher in Group II compared to Group I and the difference was statistically significant with the p-value of 0.008.

CONCLUSION

A noteworthy increase in the ALP concentration was seen in saliva in our study (Group II) may be due to increased periodontal inflammation in post menopausal women. Thus salivary ALP can be taken as an additional biomarker to early diagnosis, development and progression of periodontitis especially among post menopausal women.

Mechanisms and therapeutic effectiveness of lactobacilli

The gut microbiome is not a silent ecosystem but exerts several physiological and immunological functions. For many decades, lactobacilli have been used as an effective therapy for treatment of several pathological conditions displaying an overall positive safety profile. This review summarises the mechanisms and clinical evidence supporting therapeutic efficacy of lactobacilli. We searched Pubmed/Medline using the keyword ‘Lactobacillus’. Selected papers from 1950 to 2015 were chosen on the basis of their content. Relevant clinical and experimental articles using lactobacilli as therapeutic agents have been included. Applications of lactobacilli include kidney support for renal insufficiency, pancreas health, management of metabolic imbalance, and cancer treatment and prevention. In vitro and in vivo investigations have shown that prolonged lactobacilli administration induces qualitative and quantitative modifications in the human gastrointestinal microbial ecosystem with encouraging perspectives in counteracting pathology-associated physiological and immunological changes. Few studies have highlighted the risk of translocation with subsequent sepsis and bacteraemia following probiotic administration but there is still a lack of investigations on the dose effect of these compounds. Great care is thus required in the choice of the proper Lactobacillus species, their genetic stability and the translocation risk, mainly related to inflammatory disease-induced gut mucosa enhanced permeability. Finally, we need to determine the adequate amount of bacteria to be delivered in order to achieve the best clinical efficacy decreasing the risk of side effects.

Defining periodontal health

Assessment of the periodontium has relied exclusively on a variety of physical measurements (e.g., attachment level, probing depth, bone loss, mobility, recession, degree of inflammation, etc.) in relation to various case definitions of periodontal disease. Periodontal health was often an afterthought and was simply defined as the absence of the signs and symptoms of a periodontal disease. Accordingly, these strict and sometimes disparate definitions of periodontal disease have resulted in an idealistic requirement of a pristine periodontium for periodontal health, which makes us all diseased in one way or another. Furthermore, the consequence of not having a realistic definition of health has resulted in potentially questionable recommendations. The aim of this manuscript was to assess the biological, environmental, sociological, economic, educational and psychological relationships that are germane to constructing a paradigm that defines periodontal health using a modified wellness model. The paradigm includes four cardinal characteristics, i.e., 1) a functional dentition, 2) the painless function of a dentition, 3) the stability of the periodontal attachment apparatus, and 4) the psychological and social well-being of the individual. Finally, strategies and policies that advocate periodontal health were appraised.

I'm not sick but I'm not well,

and it's a sin to live so well.

Flagpole Sitta, Harvey Danger

On putative periodontal pathogens: an epidemiological perspective

The current understanding on the role of microbiology on periodontitis causation is reviewed. An appraisal of the literature reveals several issues that have limited the attempts to investigate candidate periodontal pathogens as causes of periodontitis and confirms that only limited epidemiological evidence is available. Several aspects of the contemporary understanding on causal inference are discussed with examples for periodontitis.

Prevalence of periodontal disease and characterization of its extent and severity in an adult population - an observational study

INTRODUCTION

Present study was undertaken to determine the prevalence of periodontal disease in an adult population and to further characterize the extent and severity of the disease.

MATERIALS AND METHODS

The study population consisted of 700 randomly selected individuals reporting to out patient department of dental college and hospital. Demographic details and lifestyle characteristics of the all the subjects were recorded and a thorough oral examination was performed. In order to evaluate the periodontal status of subjects, five indices (CAL, PD, OHI, PI and GI) were assessed and subjects having at least one site with clinical attachment loss (CAL) ≥3mm were diagnosed as having periodontitis. Further, to analyse the extent of disease, subjects having periodontitis were divided into two groups as having at least one site with CAL ≥5mm and having at least three sites with CAL ≥5mm.

RESULTS

RESULTS showed that there was a high prevalence of periodontitis amongst population with almost 72% of the individuals having at least one site with CAL ≥3mm. A trend was noted in which periodontal status worsened as the age increased. Analysing the extent and severity of disease amongst the population, results revealed that almost 41% of population had at least one site with CAL ≥5mm whereas almost 21% of individuals had at least three sites with CAL ≥5mm.

CONCLUSION

Present study provides with evidence of high prevalence of periodontal disease amongst the population. Importantly, this study also unveils the lack of awareness for dental health amidst the population.

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.

Periodontal diseases in children and adolescents: a clinician's perspective part

Contrasting forms of periodontal disease can affect children and adolescents with varying prevalence, severity and extent, leading to a diverse prognosis in these age groups. For an early diagnosis and treatment of periodontal conditions in young patients, it is essential for the dental practitioner to be able to identify and classify the disease correctly at the earliest opportunity, applying basic principles along with understanding of aetiology and risk factors. The first part of this article discusses the classification, plaque-induced and non-plaque-induced gingival diseases, localized and generalized forms of chronic, as well as aggressive, periodontitis.

CLINICAL RELEVANCE

Knowledge of different forms of periodontal diseases affecting children and adolescents may help to distinguish between different forms of diseases and have value in screening and early diagnosis of the disease.

Inactivation of epidermal growth factor by Porphyromonas gingivalis as a potential mechanism for periodontal tissue damage

Porphyromonas gingivalis is a Gram-negative bacterium associated with the development of periodontitis. The evolutionary success of this pathogen results directly from the presence of numerous virulence factors, including peptidylarginine deiminase (PPAD), an enzyme that converts arginine to citrulline in proteins and peptides. Such posttranslational modification is thought to affect the function of many different signaling molecules. Taking into account the importance of tissue remodeling and repair mechanisms for periodontal homeostasis, which are orchestrated by ligands of the epidermal growth factor receptor (EGFR), we investigated the ability of PPAD to distort cross talk between the epithelium and the epidermal growth factor (EGF) signaling pathway. We found that EGF preincubation with purified recombinant PPAD, or a wild-type strain of P. gingivalis, but not with a PPAD-deficient isogenic mutant, efficiently hindered the ability of the growth factor to stimulate epidermal cell proliferation and migration. In addition, PPAD abrogated EGFR-EGF interaction-dependent stimulation of expression of suppressor of cytokine signaling 3 and interferon regulatory factor 1. Biochemical analysis clearly showed that the PPAD-exerted effects on EGF activities were solely due to deimination of the C-terminal arginine. Interestingly, citrullination of two internal Arg residues with human endogenous peptidylarginine deiminases did not alter EFG function, arguing that the C-terminal arginine is essential for EGF biological activity. Cumulatively, these data suggest that the PPAD-activity-abrogating EGF function in gingival pockets may at least partially contribute to tissue damage and delayed healing within P. gingivalis-infected periodontia.

Generalized aggressive periodontitis and its treatment options: case reports and review of the literature

Generalized aggressive periodontitis results in rapid destruction of the periodontium and can lead to early tooth loss in the affected individuals if not diagnosed early and treated appropriately. The diagnostic features of the disease are characteristic, but the clinical presentation and patterns of destructions may vary between patients. Successful management of the disease is challenging especially if diagnosed at advanced stages of the disease, but not impossible with the current therapeutic choices for the disease. A vast array of treatment modalities is available which can be employed in the treatment of generalized aggressive periodontitis with varying success rates, but a definite guideline for the management is yet to be formulated. However, with the exponential rate of developments in periodontal research, regenerative therapy, tissue engineering, and genetic technologies, the future seems promising in regard to options at managing the disease. This paper attempts to describe the clinical and radiographic diagnostic features and the current treatment options along with a suggested protocol for comprehensive management of generalized aggressive periodontitis patients with case reports and a brief review.

Profile of chronic and aggressive periodontitis among Senegalese

Purpose

To describe the profile of chronic and aggressive periodontitis among Senegalese (West Africans) attending the Institute of Dentistry of Dakar.

Methods

A retrospective study was conducted with an inclusion period running from 2001 to 2008. The sample included 413 chronic periodontitis and 151 aggressive periodontitis cases, among them 299 males and 265 females selected from 2,274 records. A Student's independent t-test or Pearson chi-squared test was used for data analysis.

Results

The proportion of females with aggressive periodontitis was significantly higher than those with chronic periodontitis (64.9% vs. 40.4%, P<0.001). The aggressive periodontitis patients had an average age of 28.1±8.9 years, and had lost less than 3 teeth. Less than a third of them reported using a toothbrush. Attachment loss was as high as 8 mm and severe lesions had spread to an average of 12 teeth with maximum alveolar bone loss up to 80%. The chronic periodontitis patients had an average age of 44.9±14.0 and had lost on average less than 3 teeth. Nearly 75% used a toothbrush. Attachment loss was significantly higher and lesions were more extensive in the aggressive periodontitis. Chronic periodontitis is associated with risk factors such as smoking or diabetes mellitus in 12.8% versus 0.7% in aggressive periodontitis (P<0.001). Differences between the two groups for most clinical and radiographic parameters were statistically significant.

Conclusions

The profile of aggressive periodontist is characterized by more severe lesions than chronic periodontitis, whereas tooth loss experience is similar in both forms.

Impact of Porphyromonas gingivalis inoculation on ligature-induced alveolar bone loss. A pilot study in rats

BACKGROUND AND OBJECTIVE

Periodontitis is a polymicrobial infection characterized by the loss of connective tissue attachment, periodontal ligament and alveolar bone. The aim of this study was to evaluate the impact of Porphyromonas gingivalis inoculation on the ligature-induced alveolar bone loss (ABL) model in rats.

MATERIAL AND METHODS

Forty male Wistar rats were randomly assigned to the following groups: G1, control (n = 10); G2, ligature-induced ABL (n = 15); and G3, ligature-induced ABL + P. gingivalis inoculation (n = 15). Rats in G2 and G3 were killed 15, 21 and 30 d after ligature placement, and the following parameters were assessed: microbiological load; ABL; and interleukin (IL)-1β (Il1beta)/Il1ra, Il6/Il10 and Rankl/osteoprotegerin (Opg) mRNA ratios in the gingival tissues, as determined by quantitative PCR.

RESULTS

Microbiological analyses demonstrated that rats in G1, G2 and G3 were positive for the presence of bacteria (determined using PCR amplification of the 16S gene), but that only the treatment sites of rats in G3 were positive for P. gingivalis at all time-points investigated. Histometrically, significant bone loss (p<0.001) was observed for both ligated groups (G2 and G3) compared with the nonligated group (G1), with higher ABL observed for G2 at all the experimental time-points. Furthermore, gene-expression analysis demonstrated that the presence of P. gingivalis in the dentogingival area significantly decreased the Il1β/Il1ra, Il6/Il10 and Rankl/Opg mRNA ratios compared with ligature alone.

CONCLUSION

Within the limits of this pilot study, it was concluded that inoculation of P. gingivalis affected the ligature-induced ABL model by the induction of an anti-inflammatory and antiresorptive host response.

The clinical assessment of aggressive periodontitis patients

Purpose

Few epidemiologic studies have investigated aggressive periodontitis in Koreans, but such studies of disease prevalence and other clinical characteristics would be invaluable in providing proper treatment. The aim of this study was to assess the prevalence of aggressive periodontitis and to measure the extent of associated periodontal breakdown.

Methods

The study population consisted of 1,692 patients who visited the Department of Periodontology, Wonkwang Daejeon Dental Hospital from January to December, 2010. Clinical parameters (probing depth, gingival recession, periodontal attachment loss) were measured by a single examiner, and radiographic examination was performed at the baseline.

Results

Twenty-eight (1.65%) patients showed clinical features of aggressive periodontitis, of which 27 patients exhibited the generalized form, and 1 exhibited the localized form. There was no significant difference between the percentage of male and female patients. The probing pocket depth of the maxillary first molar was deeper than that of the other teeth and gingival recession was also the most serious at the maxillary first molar. The periodontal attachment loss was the highest at the maxillary first molar. The average number of missing teeth was 1.29 per subject. Loss of the second molar was prominent.

Conclusions

Within the limitations of this study, the periodontal breakdown evaluated by attachment loss was found to be most severe at the first molars of aggressive periodontitis patients. However, further large scale multicenter studies are necessary to access more precise data, including prevalence.

Short-term benefits of the adjunctive use of metronidazole plus amoxicillin in the microbial profile and in the clinical parameters of subjects with generalized aggressive periodontitis

AIM

The aim of this study was to evaluate the clinical and microbiological effects of scaling and root planing (SRP) alone or combined with metronidazole (MTZ) and amoxicillin (AMX) in the treatment of subjects with generalized aggressive periodontitis (GAgP).

MATERIALS AND METHODS

A double-blind, placebo-controlled, randomized clinical trial was conducted in 30 subjects receiving SRP alone or combined with MTZ (400 mg 3 x per day) and AMX (500 mg 3 x per day) for 14 days. Clinical and microbiological examinations were performed at baseline and 3 months post-SRP. Nine subgingival plaque samples per subject were analysed using checkerboard DNA-DNA hybridization.

RESULTS

Subjects receiving MTZ and AMX showed the greatest improvements in the mean full-mouth probing depth and clinical attachment level and at initially intermediate and deep sites. The most beneficial changes in the microbial profile were also observed in the MTZ+AMX group, which showed the lowest proportions of the red complex as well as a significant decrease in the proportions of the orange complex after treatment. The antibiotic therapy also reduced the levels of Aggregatibacter actinomycetemcomitans at initially deep sites.

CONCLUSION

Subjects with GAgP significantly benefit from the adjunctive use of MTZ and AMX. The short-term advantages are observed in the clinical and microbiological parameters.

A member of the peptidase M48 superfamily of Porphyromonas gingivalis is associated with virulence in vitro and in vivo

Background

In vivo-induced antigen technology was previously used to identify 115 genes induced in Porphyromonas gingivalis W83 during human infection. One of these, PG2197, a conserved hypothetical protein which has homology to a Zn-dependent protease, was examined with respect to a role in disease.

Design

The expression of PG2197 in human periodontitis patients was investigated, but as there is increasing evidence of a direct relationship between P. gingivalis and cardiovascular disease, a mutation was constructed in this gene to also determine its role in adherence, invasion, and persistence within human coronary artery endothelial cells (HCAEC) and neutrophil killing susceptibility.

Results

Plaque samples from 20 periodontitis patients were analyzed by real-time PCR, revealing that PG2197 was expressed in 60.0% of diseased sites compared to 15.8% of healthy sites, even though P. gingivalis was detected in equal numbers from both sites. The expression of this gene was also found to be up-regulated in microarrays at 5 and 30 min of invasion of HCAEC. Interestingly, a PG2197 mutant displayed increased adherence, invasion, and persistence within HCAEC when compared to the wild-type strain.

Conclusion

This gene appears to be important for the virulence of P. gingivalis, both in vivo and in vitro.

Microbiological diversity of generalized aggressive periodontitis by 16S rRNA clonal analysis

BACKGROUND/AIM

The purpose of this study was to determine the bacterial diversity in the subgingival plaque of subjects with generalized aggressive periodontitis by using culture-independent molecular methods based on 16S ribosomal DNA cloning.

METHODS

Samples from 10 subjects with generalized aggressive periodontitis were selected. DNA was extracted and the 16S rRNA gene was amplified with the universal primer pairs 9F and 1525R. Amplified genes were cloned, sequenced, and identified by comparison with known 16S rRNA sequences.

RESULTS

One hundred and ten species were identified from 10 subjects and 1007 clones were sequenced. Of these, 70 species were most prevalent. Fifty-seven percent of the clone (40 taxa) sequences represented phylotypes for which no cultivated isolates have been reported. Several species of Selenomonas and Streptococcus were found at high prevalence and proportion in all subjects. Overall, 50% of the clone libraries were formed by these two genera. Selenomonas sputigena, the species most commonly detected, was found in nine of 10 subjects. Other species of Selenomonas were often present at high levels, including S. noxia, Selenomonas sp. EW084, Selenomonas sp. EW076, Selenomonas FT050, Selenomonas sp. P2PA_80, and Selenomonas sp. strain GAA14. The classical putative periodontal pathogens, such as, Aggregatibacter actinomycetemcomitans, was below the limit of detection and was not detected.

CONCLUSION

These data suggest that other species, notably species of Selenomonas, may be associated with disease in generalized aggressive periodontitis subjects.

Effects of laser irradiation on the release of basic fibroblast growth factor (bFGF), insulin like growth factor-1 (IGF-1), and receptor of IGF-1 (IGFBP3) from gingival fibroblasts

Various studies have shown biostimulation effects of laser irradiation by producing metabolic changes within the cells. Little is known about the biological effect of laser irradiation on the oral tissues. Among the many physiological effects, it is important to recognize that low-level laser therapy (LLLT) may affect release of growth factors from fibroblasts. Therefore, the aim of the present study was to determine whether the laser irradiation can enhance the release of basic fibroblast growth factor (bFGF), insulin-like growth factor-1 (IGF-1), and receptor of IGF-1 (IGFBP3) from human gingival fibroblasts (HGF). The number of all samples in the study were 30, and the samples were randomly divided into three equal groups; In the first group (single dose group), HGF were irradiated with laser energy of 685 nm, for 140 s, 2 J/cm(2) for one time, and in the second group, energy at the same dose was applied for two consecutive days (double dose group). The third group served as nonirradiated control group. Proliferation, viability, and bFGF, IGF-1, IGFBP3 analysis of control and irradiated cultures were compared with each other. Both of the irradiated groups revealed higher proliferation and viability in comparison to the control group. Comparison of the single-dose group with the control group revealed statistically significant increases in bFGF (p < 0.01) and IGF-1 (p < 0.01), but IGFBP3 increased insignificantly (p > 0.05). When the double dose group was compared with the control group, significant increases were determined in all of the parameters (p < 0.01). In the comparison of the differences between the two irradiated groups (one dose and two doses), none of the parameters displayed any statistically significant difference (p > 0.05). In both of the laser groups, LLLT increased the cell proliferation and cell viability. The results of this study showed that LLLT increased the proliferation of HGF cells and release of bFGF, IGF-1, and IGFBP3 from these cells. LLLT may play an important role in periodontal wound healing and regeneration by enhancing the production of the growth factors.

Influence of periodontal therapy on the regulation of soluble cell adhesion molecule expression in aggressive periodontitis patients

BACKGROUND

Inflammatory periodontal disease is associated with an increased risk of cardiovascular disease. Circulating cell adhesion molecules (CAM) (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], and E-selectin) have been suggested as potential candidate markers of endothelial dysfunction, which contribute to the pathogenesis of cardiovascular diseases. The regulation of CAM in subjects with severe periodontitis and the influence of periodontal intervention on systemic CAM levels are not clear. The aim of this study was to determine whether intensive periodontal therapy reduces serum levels of CAM in patients with generalized aggressive periodontitis.

METHODS

Blood samples were collected at six treatment time points from 21 patients with previously untreated generalized aggressive periodontitis (mean age: 34.6 +/- 4.3 years). Patients received subgingival scaling and root planing and antibiotic therapy and were monitored over a 6-month recall period. Serum levels of soluble ICAM-1 (sICAM-1), VCAM-1 (sVCAM-1), and E-selectin (sE-selectin) were measured by enzyme-linked immunosorbent assay.

RESULTS

sE-selectin plasma levels decreased significantly (P <0.01) during periodontal therapy. Mean plasma levels were 65.95 ng/ml before treatment and 44.71 ng/ml 6 months after antibiotic therapy. sICAM-1 and sVCAM-2 serum levels were unaffected by therapeutic intervention.

CONCLUSIONS

Periodontal therapy reduces plasma sE-selectin levels. Whether this leads to a reduction in risk of future cardiovascular events in patients with aggressive periodontal disease warrants further studies.

Periodontal Disease in Patients From the Original Kostmann Family With Severe Congenital Neutropenia

BACKGROUND

Patients with Kostmann syndrome (severe congenital neutropenia [SCN]) typically normalize their absolute neutrophil count (ANC) upon granulocyte colony-stimulating factor (G-CSF) therapy. However, although they no longer experience life-threatening bacterial infections, they frequently still have recurrent gingivitis and even severe periodontitis, often starting in early childhood.

METHODS

We studied the periodontal disease in the four surviving patients belonging to the family originally described by Kostmann. Their odontological records, x-rays, color photos, bacterial cultures, serum antibodies to oral bacteria, and histopathological examinations were reviewed. The data were also correlated to previous investigations on their antibacterial peptides and molecular biology.

RESULTS

Three patients had periodontal disease, despite normal ANC and professional dental care, and had neutrophils deficient in antibacterial peptides. One of these patients also had a heterozygous mutation in the neutrophil elastase gene, had severe periodontal disease and overgrowth of the periodontal pathogen Actinobacillus actinomycetemcomitans in the dental flora, and 15 permanent teeth had been extracted by the age of 27. One bone marrow-transplanted patient had no periodontal disease.

CONCLUSIONS

Normalized ANC levels are not sufficient to maintain normal oral health in SCN patients, and because neutrophils are important for first-line defense and innate immunity, the deficiency of the antibacterial peptide LL-37 probably explains their chronic periodontal disease. Professional dental care is still important for SCN patients, despite treatment with G-CSF and normal ANC levels. Whether antibacterial peptides play a role in the pathogenesis of periodontitis in other patients remains to be elucidated.

The effects of periodontal therapy on vascular endothelial function: a pilot trial

BACKGROUND

Chronic periodontal infection is associated with an increased risk of coronary heart disease. Although the mechanism responsible for the relationship between periodontal disease and cardiovascular events is not fully understood, it is hypothesized that the chronic inflammatory burden of periodontal disease may lead to impaired functioning of the vascular endothelium.

METHODS

Twenty-two otherwise healthy adults with moderate to severe periodontitis who underwent complete mouth disinfection were evaluated to determine if periodontal therapy would result in improved endothelial function and a decrease in serum inflammatory markers. Subjects had measurements of periodontal disease severity, flow-mediated (endothelium-dependent), and nitroglycerin-mediated (endothelium-independent) dilation of the brachial artery, serum C-reactive protein (CRP) and interleukin 6 (IL-6), and serum total and high-density lipoprotein cholesterol levels on 2 baseline visits separated by 1 month and, again, 1 month after treatment.

RESULTS

There were no significant changes in clinical periodontal measures, flow-mediated dilation, nitroglycerin-mediated dilation, CRP, IL-6, total cholesterol, or high-density lipoprotein cholesterol between the repeated baseline measurements. Periodontal treatment, however, resulted in significant improvements in periodontal pocketing, flow-mediated dilation, and serum IL-6, as well as a trend toward reduction in serum CRP; there were no significant changes in nitroglycerin-mediated dilation or in cholesterol levels.

CONCLUSIONS

These results represent proof of concept that improvement in endothelial function, as measured by flow-mediated dilation of the brachial artery, may be possible through near-elimination of chronic oral infection and suggest that the conduct of a larger controlled trial is justified.

Expression of activated transcription factor nuclear factor-kappaB in periodontally diseased tissues

BACKGROUND

Chronic periodontitis is an inflammatory disease found mainly in adults. Little is known about molecular level changes associated with host response in this condition. Nuclear factor-kappaB (NF-kappaB) is a transcription factor implicated in immune and inflammatory responses. NF-kappaB activation has also been reported to be associated with many chronic inflammatory diseases. The purpose of this paper was to compare the nuclear and cytoplasmic expression of NF-kappaB transcription factor (p50/p65) and cytoplasmic expression of IkappaB in periodontal tissues of periodontitis patients and controls.

METHODS

Twenty patients with chronic periodontitis and 20 healthy controls were included in the study. Gingival tissues taken during extraction were processed for immunohistochemical staining and evaluation.

RESULTS

Nuclear (activated) p50 was found in 90% of periodontal patient tissues compared to only 30% of healthy tissues. A more significant result was obtained with p65 (75% versus 5%). Intense cytoplasmic immunoreactivity was also observed in periodontitis tissues. IkappaB, the inhibitor of NF-kappaB, was expressed only in 5% of periodontally diseased tissues.

CONCLUSION

Activation of NF-kappaB (p50/p65) is significant in periodontally diseased tissues, suggesting the potential of inhibitors of NF-kappaB in managing periodontitis.

Microbiological profile of early onset/aggressive periodontitis patients

OBJECTIVES

The objectives of this study were to characterize the bacterial profile and to seek possible bacterial associations in the subgingival microbiota of early onset periodontitis/aggressive periodontitis patients by using two different techniques, culture and immunofluorescence.

MATERIAL AND METHODS

The study group consisted of 66 systemically healthy individuals with evidence of early onset periodontitis - 41 females and 25 males aged 23-35 years (mean 31.1 +/- 3.1 years). Bacterial samples were collected from the deepest site in each quadrant, resulting in a total of 264 sites with a mean probing pocket depth of 6.6 +/- 1.5 mm. Samples were cultured anaerobically and in 10% CO(2) using selective and nonselective media, and isolates were characterized to species level. Indirect immunofluorescence using monoclonal antibodies was applied to detect Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia (Bacteroides forsythus, Tannerella forsythensis), Prevotella intermedia/Prevotella nigrescens, Campylobacter rectus, Peptostreptococcus micros and Actinomyces israelii.

RESULTS

93.6% of sampled sites showed bleeding on probing and 23.5% were positive for suppuration. P. intermedia/P. nigrescens, P. gingivalis, and C. rectus were detected in 77.3-85.9% of samples using culture methods and in 85.6-91.3% using immunofluorescence. P. micros and A. actinomycetemcomitans were found, respectively, in 63.3% and 25.0% of all sites using culturing and in 58.7% and 27.7% sites using immunofluorescence. Significantly strong positive associations were observed between T. forsythia and C. rectus (odds ratio 109.46), and T. forsythia and P. gingivalis (odd ratio 90.26), whereas a negative association was seen between P. intermedia/P. nigrescens and A. actinomycetemcomitans (odds ratio 0.42). Coinfection by P. gingivalis, T. forsythia, P. intermedia/P. nigrescens and C. rectus was observed in 62.1% of the test sites, and in 89.4% of the studied subjects. The sensitivity of immunofluorescence for T. forsythia, C. rectus, P. intermedia/P. nigrescens and P. gingivalis was found to be very high (0.99-0.94) using culture as the reference detection method. The agreement between culture and immunofluorescence in detecting the presence or absence of the investigated species was 85.2-88.1% for P. gingivalis, P. intermedia/P. nigrescens, C. rectus, and T. forsythia, 75.9% for A. actinomycetemcomitans and 70.4% for P. micros.

CONCLUSIONS

The microbial profile of the early onset/aggressive periodontitis population was complex. The agreement between the two detection methods was very high.

Prevalence of Human Herpesviruses in Patients with Aggressive Periodontitis

BACKGROUND

Recent studies have demonstrated that various human viruses, especially cytomegalovirus (HCMV) and Epstein-Barr virus type-1 (EBV-1), seem to play a part in the pathogenesis of human periodontitis. The aim of this investigation was to evaluate the subgingival presence of HCMV and EBV in patients with aggressive periodontitis (AgP) and healthy subjects and to examine the effect of treatment on the incidence of these viruses 3 months following surgery.

METHODS

A polymerase chain reaction (PCR) method determined the presence of HCMV and EBV-1. Subgingival plaque samples from 17 consecutive AgP patients and 16 healthy controls were collected. The following indices were measured: plaque index (PI), gingival index (GI), probing depths (PD), and clinical attachment loss (CAL). Clinical parameters were assessed pretherapy and at 3 months following surgical and antimicrobial therapy.

RESULTS

HCMV was detected in 64.7% of AgP patients but not detected in healthy subjects (P < 0.001) and EBV-1 in 70.6% of AgP patients and 6.3% of the healthy controls (P < 0.001). HCMV and EBV-1 coinfection was detected in 41.7% of AgP patients. A statistically significant decrease was found in all clinical parameters 3 months after treatment. There was a statistically significant decrease in HCMV and EBV-1 following therapy (P < 0.001; no HCMV; 1 patient with EBV-1).

CONCLUSIONS

These findings indicate that subgingival presence of EBV-1 HCMV is strongly associated with aggressive periodontitis, and coinfection with HCMV and EBV-1 appears to be particularly deleterious to periodontal health.

Distribution of Periodontal Pathogens in Korean Aggressive Periodontitis

BACKGROUND

Microbial associations in aggressive periodontitis versus different ethnic origins are substantially unknown. We undertook this study to determine the prevalence of seven putative periodontopathogens in Korean patients and to evaluate microbial differences in localized and generalized aggressive periodontitis patients.

METHODS

Thirty-nine aggressive periodontitis patients between 20 and 35 years old (24 males and 15 females; mean age 29.6 years) were selected according to clinical criteria. The patients were subclassified into 17 localized and 22 generalized aggressive periodontitis patients. In each of the 39 individuals, subgingival plaque samples were collected from four diseased teeth (> or = 6 mm probing depth, 156 sites) and one healthy site (< or = 3 mm probing depth, 39 sites). Polymerase chain reaction (PCR) of the 16S ribosomal RNA gene fragments (about 530 bp) of plaque bacteria and their subsequent detection by dot-blot hybridization using specific oligonucleotide probes were performed to determine the presence of seven periodontopathogens.

RESULTS

The prevalences were 75% for Actinobacillus actinomycetemcomitans, 94.2% for Tannerella forsythensis (formerly Bacteroides forsythus), 99.4% for Fusobacterium sp., 85.9% for Micromonas micros (formerly Peptostreptococcus micros), 96.8% for Porphyromonas gingivalis, 78.8% for Prevotella intermedia, and 96.8% for Treponema sp. The prevalences of these bacteria were significantly higher in diseased sites than in healthy sites. Logistic regression analysis showed that P. intermedia was more significantly associated with generalized aggressive periodontitis than the localized form, with an odds ratio of 3.28 (95% confidence interval 1.26-8.56, P = 0.015).

CONCLUSIONS

Our results demonstrate that the seven periodontal pathogens analyzed are strongly associated with Korean aggressive periodontitis. In particular, P. intermedia are more significantly associated with generalized aggressive periodontitis, a more severe and progressive form, than with localized aggressive periodontitis.

Salivary IgA in response to periodontal treatment

There is evidence that the quantity of antigen load is crucial for the activation of IgA immune responses. In order to investigate the relevance of these findings in aggressive periodontitis, salivary antibody responses were measured during non-surgical and antibiotic treatment. Twenty-one patients with generalized aggressive periodontitis were monitored for total salivary IgA and IgA reactive to Porphyromonas gingivalis in resting and stimulated whole saliva. Non-surgical treatment included full-mouth professional tooth cleaning and subgingival scaling and root planing (SRP) under local anesthesia. Patients were recalled at 3 months and 6 months following systemic antibiotic treatment. Non-parametric statistics showed significant improvements in the clinical parameters in all patients. Between baseline and 4 wk following SRP, median concentrations of total IgA decreased both in resting (-46%) and in stimulated (-33%) saliva. The P. gingivalis-specific IgA activity showed a twofold increase at 4 wk after SRP. In addition to these changes, periodontal treatment of aggressive periodontitis did not appear to affect salivary IgA, and there were no significant correlations of IgA to the clinical parameters. In conclusion, salivary IgA responses during periodontal treatment were not found to have a diagnostic or prognostic significance.

The relationship of stress and anxiety with chronic periodontitis

AIM

This case-control study investigates the relationship of stress and anxiety with periodontal clinical characteristics.

METHOD

Seventy-nine selected patients (mean age 46.8+/-8 years) were assigned to three groups in accordance with their levels of probing pocket depth (PPD): control group (PPD< or =3 mm, n=22), test group 1 (at least four sites with PPD > or =4 mm and < or =6 mm, n=27) and test group 2 (at least four sites with PPD >6 mm, n=30). An inclusion criterion of the study required that patients presented a plaque index (PI) with a value equal to or larger than 2 in at least 50% of dental surfaces. All subjects were submitted to stress and anxiety evaluations. Stress was measured by the Stress Symptom Inventory (SSI) and the Social Readjustment Rating Scale (SRRS), while the State-Trait Anxiety Inventory (STAI) was used to assess anxiety. Clinical measures such as PI, gingival index (GI), PPD and clinical attachment level (CAL) were collected. Patient's medical history and socioeconomic data were also recorded.

RESULTS

The mean clinical measures (PI, GI, PPD and CAL) obtained for the three groups, were: control group, 1.56+/-0.32, 0.68+/-0.49, 1.72+/-0.54 and 2.04+/-0.64 mm; group 1, 1.56+/-0.39, 1.13+/-0.58, 2.67+/-0.67 and 3.10+/-0.76 mm, group 2, 1.65+/-0.37, 1.54+/-0.46, 4.14+/-1.23 and 5.01+/-1.60 mm. The three groups did not differ with respect to percentage of clinical stress, scores of the SRRS, trait and state anxiety. Frequency of moderate CAL (4-6 mm) and moderate PPD (4-6 mm) were found to be significantly associated with higher trait anxiety scores after adjusting for socioeconomic data and cigarette consumption (p<0.05).

CONCLUSIONS

Based on the obtained results, individuals with high levels of trait anxiety appeared to be more prone to periodontal disease.

Defining and classifying periodontitis: need for a paradigm shift?

The past two decades have witnessed a large number of proposals for the classification of periodontitis. These proposals are all founded in an essentialistic disease concept, according to which periodontitis is a link between the causes and the signs and symptoms of periodontitis. Essentialistic definitions are necessarily rather imprecise and thereby subject to multiple interpretations. Consequently, it remains unknown to what extent current knowledge regarding 'different' forms of periodontitis is based on the 'same' type of patients. However, periodontitis is a syndrome, the clinical manifestations of which may come in all sizes. Thereby, periodontitis has no diagnostic truth, just as there is no natural basis for a sharp distinction between health and disease or between 'different' forms of periodontitis. Recognition of these facts and adoption of a nominalistic approach to the definition of periodontitis is needed to provide a rational framework for the development of a classification system that meets the needs of both clinicians and scientists.

Methodological considerations on descriptive studies of induced periodontal diseases in rats

The aim of this study was to show the technique and the methodological approach used in describing histological characteristics of induced periodontal disease in rats. To reach that inflammatory process, periodontal disease was induced by ligature, with or without sucrose-rich diet. Twenty-four female adult (60 days old) Wistar rats were divided in four groups: Group 1, or control (which received standard diet), Group 2 (which received ligature around the upper second molars and a standard diet), Group 3 (which received a sucrose-rich diet), and Group 4 (which received ligature around the upper second molars and a sucrose-rich diet). The animals were followed for a period of 30 days, after which they were sacrificed. The upper second molars were removed, processed, and the histological characteristics were analyzed by a descriptive dichotomous method. The results were analyzed by the Fisher's exact test (significance level of 95%) and by a residual test, which showed the relation between groups and histological characteristics. The animals which received ligature (Groups 2 and 4) showed histological characteristics related with periodontitis, whilst the animals without ligatures showed no periodontal destruction. This was shown by a distribution of these groups in extremes of a graphic representation. The use of a ligature, as done in this study, was able to promote a chronic inflammatory process in the periodontium of rats, regardless of the adopted diet. The correspondence factorial analysis was capable of showing these characteristics, being one more tool to be used in histological research.

Analysis of vitamin D and Fcgamma receptor polymorphisms in Japanese patients with generalized early-onset periodontitis

Early-onset periodontitis (EOP) is considered to have a genetic basis which has not been clearly defined. Genetic polymorphisms of the vitamin D receptor (VDR-B-b) and the immunoglobulin-Fc-gamma receptor IIIb (FcgammaRIIIb-NA1-NA2) are associated with bone metabolism and infectious diseases, respectively. The purpose of this study was to investigate the associations of EOP with VDR and FcgammaRIIIb polymorphisms. Subjects were comprised of those with generalized EOP (G-EOP, n = 42), adult periodontitis (AP, n = 52), and healthy control (HC, n = 55). VDR and FcgammaRIIIb genotypes were determined by allele-specific polymerase chain-reactions. Our results indicated that frequencies of the VDR-B non-carrier and the FcgammaRIIIb-NA2 carrier were lower in the G-EOP compared with the AP and HC groups. Furthermore, we found a strong association between G-EOP and the VDR-Fc-gammaRIIIb composite genotype (G-EOP vs. AP - OR = 5.09, p = 0.009; G-EOP vs. HC - OR = 5.93, p = 0.004). In conclusion, no correlation was found between the VDR genotype and G-EOP. However, the VDR and Fc-gammaRIIIb genotype combination may be associated with susceptibility to G-EOP.

Association of early onset periodontitis microbiota with aspartate aminotransferase activity in gingival crevicular fluid

OBJECTIVES

The objective of this study was to determine the relationship between the activity of the enzyme aspartate aminotransferase (AST) in gingival crevicular fluid (GCF) using the colorimetric PerioGard (PTM) test and the subgingival microflora in early onset periodontitis lesions.

MATERIAL AND METHODS

The study population consisted of 25 otherwise healthy individuals exhibiting early onset periodontitis (EOP). In each patient four experimental sites were identified comprising one deep periodontal pocket (PD >5 mm) randomly chosen in each quadrant. Bacterial samples were obtained from the experimental sites, consecutively cultured anaerobically and in 10% CO(2) using selective and nonselective media. Isolates were characterized to species level by conventional biochemical tests and various identification kits. Clinical measurements as well as AST activity, assessed either as positive or negative using the PTM, were recorded at the same sites.

RESULTS

Sixty-two sites exhibited AST positive and 38 AST negative activity. Analysis of bacterial counts using the ANOVA (Mann Whitney U-test) showed that Streptococcus intermedius, Peptostreptococcus micros, Campylobacter concisus, Bacteroides forsythus, Camplobacter gracilis, Campylobacter rectus and Selenomonas sputigena were significantly higher in sites with AST-positive activity. The odds ratio of having high prevalence of S. intermedius, P. micros, C. concisus, B. forsythus, C. gracilis, C. rectus and S. sputigena in the presence of a positive AST site was very high (range: 3.5-17.0). Streptococcus sanguis, Actinomyces naeslundii, Gemella morbillorum, Capnocytophaga gingivalis, Veillonella parvula, Fusobacterium varium, Eubacterium lentum and Prevotella oralis were detected in significantly higher proportions in sites with AST negative activity and manifested a negative odds ratio in the presence of AST positive sites. The logistic regression analysis revealed that smoking and bleeding upon probing showed a significant association with AST activity, while plaque and suppuration were not found to be significant predictors of AST activity. The co-infection of Porphyromonas gingivalis, B. forsythus and P. micros, or P. gingivalis, B. forsythus and C. rectus were found to be significantly associated with the AST activity (p<0.001). AST positive sites revealed significantly higher occurrence of co-infections by P. gingivalis, B. forsythus, S. sputigena or by P. gingivalis, B. forsythus, S. intermedius than AST negative sites (p<0.001). P. gingivalis, B. forsythus, A. naeslundii co-infection was found significantly higher in the AST negative sites (p<0.001).

CONCLUSIONS

The present study found a high level of agreement between the presence of putative periodontal pathogens and positive AST scores at periodontal sites that clinically were considered to be potentially disease active. Prospective studies should be performed to confirm the findings.

Herpes viruses and periodontopathic bacteria in early-onset periodontitis

OBJECTIVES

This study examined the occurrence of human herpes viruses and suspected periodontopathic bacteria in early-onset periodontitis patients who experienced progressive disease in at least 2 periodontal sites during the maintenance phase of therapy.

MATERIAL AND METHODS

In each of 16 individuals (9 male and 7 female; mean age 33.1+/-2.6 years), subgingival plaque samples were collected from 2 deteriorating and 2 stable periodontitis sites. A nested polymerase chain reaction method determined the presence of human cytomegalovirus (HCMV), Epstein-Barr virus type 1 (EBV-1) and herpes simplex virus (HSV). A 16s rRNA polymerase chain reaction method identified Porphyromonas gingivalis, Dialister pneumosintes, Bacteroides forsythus and Actinobacillus actinomycetemcomitans.

RESULTS

HCMV was detected in 59.4% of active and in 12.5% of stable sites (p<0.001), EBV-1 in 43.8% of active and in 12.5 % of stable sites (p=0.01), HSV in 34.5% of active and in 9.4% of stable sites (p=0.03), and co-infection with any of the 3 test herpesviruses in 43.8% of active and in 3.1% of stable sites (p<0.001). P. gingivalis was detected in 71.9% of active and in 37.5% of stable sites (p=0.01), D. pneumosintes in 62.5% of active and in 18.8% of stable sites (p=0.04), co-infection with P. gingivalis and D. pneumosintes in 50% of active and in 0% of stable sites (p<0.001), and co-infection with any 3 or 4 of the test bacteria in 40.6% of active and in 0% of stable sites (p=0.001). All periodontitis sites showing herpesvirus co-infection and all but one site showing P. gingivalis and D. pneumosintes co-infection revealed bleeding upon probing.

CONCLUSIONS

HCMV, EBV-1, HSV and herpesvirus co-infection, as well as P. gingivalis, D. pneumosintes and P. gingivalis-D. pneumosintes co-infection were statistically associated with active periodontitis. Herpesviruses are immunosuppressive and may set the stage for overgrowth of subgingival P. gingivalis, D. pneumosintes and other periodontopathic bacteria. Understanding the significance of herpesviruses in human periodontitis may allow for improved diagnosis, more specific therapy and, ultimately, disease prevention.

Expression of growth-factor receptors in normal and regenerating human periodontal cells

Growth factors are biologically active mediators that bind to specific receptors on target cells and regulate genes involved in cell growth, wound healing and regeneration. The expression of these receptors is thus of fundamental importance for the response of the cells to the factors. The aim here was to examine, using immunohistochemistry and flow cytometry, the expression of growth factor receptors in normal gingiva, periodontal ligament and in cells derived from these tissues, and also in regenerated tissues following guided tissue regeneration (GTR). By immunocytochemistry platelet-derived growth factor receptor-alpha (PDGF-Ralpha) was not detected in any of the tissues, whereas the PDGF-Rbeta and transforming growth factor-beta receptor types I and II (TGF-beta RI, RII) appeared to be upregulated in regenerated tissues compared with gingival and periodontal ligament tissues. Epidermal growth factor receptor (EGF-R) was also notably elevated in the regenerated tissue and was strongly expressed in the gingival epithelium but not in the periodontal ligament. Neither were fibroblast growth factor receptor-I (FGF-RI) or insulin-like growth factor receptor (IGF-R) detected in the periodontal ligament, nor in the gingiva, but they sometimes stained weakly in the regenerated tissues. Flow cytometry (FCM) showed that all the cells derived from the normal gingiva and the periodontal ligament expressed the PDGF-Rbeta, whereas the TGF-beta RI and RII, FGF-RI and IGF-R were detected in only a proportion of the total cells. In contrast, none of the cells expressed the PDGF-Ralpha or the EGF-R. These observations show that the growth factor receptors are differentially expressed by the periodontal tissues and cells and suggest that the corresponding factors may also be differentially involved in periodontal wound healing and regeneration.

The clinical and microbiological effects of systemic ornidazole in sites with and without subgingival debridement in early-onset periodontitis patients

BACKGROUND

The purpose of this study was to evaluate the clinical and microbiological effects of systemic ornidazole (ORN) in sites with or without subgingival debridement in early-onset periodontitis (EOP) patients.

METHODS

Two pooled bacterial samples consisting of 4 sites each (scaled and non-scaled sites) were obtained from 30 individuals exhibiting EOP. All patients received oral hygiene instruction (OHI), supragingival scaling and ORN. Subgingival scaling and root planing (SRP) was carried out only in scaled sites. Bacterial samples were taken at baseline (BL) and 1 week and 2, 6, and 12 months after systemic ornidazole administration (500 mg/bid for 7 days). One more sample was taken at scaled sites, one week after SRP.

RESULTS

One week following SRP (scaled sites) Gram-negative facultative and anaerobic rods were significantly reduced while Gram-positive facultative cocci were significantly increased. After ORN administration, P. gingivalis, P. denticola, P. intermedia, B. forsythus, C. rectus, and S. sputigena were no longer detectable in either scaled or non-scaled sites. A statistically significant long-term (2, 6, and 12 months) reduction of P. gingivalis, P. intermedia, P. loescheii, B. forsythus, and C. rectus and a pronounced increase of S. milleri, S. oralis, and S. sanguis counts in both scaled and non-scaled sites were detected in comparison to baseline. A sustained reduction of bleeding tendency and of probing depth was also observed in both scaled and non-scaled sites.

CONCLUSIONS

ORN combined with SRP effects beneficial shifts in the bacterial population associated with substantial clinical improvement, thereby indicating that ORN is effective adjunct in the treatment of EOP deep periodontal pockets where anaerobic bacteria are predominant.

The Fcgamma receptor genotype as a risk factor for generalized early-onset periodontitis in Japanese patients

BACKGROUND

Genetic polymorphisms of immunoglobulin G (IgG) Fc receptors (FcgammaR) were recently shown to be associated with recurrence rates of adult periodontitis (AP). The purpose of this study was to evaluate whether FcgammaR polymorphisms are also associated with generalized early-onset periodontitis (G-EOP) in Japanese patients.

METHODS

Thirty-eight Japanese patients with G-EOP and 83 Japanese patients with AP were identified according to established clinical criteria, including measurements of probing depth, clinical attachment level, and alveolar bone level. FcgammaR genotypes for 3 bi-allelic polymorphisms were determined in these G-EOP and AP patients and 104 race-matched healthy controls by means of allele-specific polymerase chain reactions.

RESULTS

There was a significant difference in the distribution of FcgammaRIIIb genotypes between G-EOP patients and healthy controls (P = 0.02). Additionally, a significant over-representation of FcgammaRIIIb-NA2 allele was observed in G-EOP patients as compared to AP patients and controls (P= 0.02, P= 0.009, respectively). Moreover, we found a strong association between G-EOP and the composite genotype comprising FcgammaRIIIb-NA2 and FcgammaRIIIa-158F (G-EOP versus controls: odds ratio 2.4, 95% CI 1.0-6.0, chi2 = 4.13, P= 0.04).

CONCLUSIONS

This study indicates that the FcgammaRIIIb-NA2 allele and possibly FcgammaRIIIa-158F could be associated with susceptibility to G-EOP in Japanese patients.

Dental plaque-induced gingival diseases

Gingival diseases are a diverse family of complex and distinct pathological entities found within the gingiva that are the result of a variety of etiologies. There are several clinical characteristics common to all gingival diseases and these features include clinical signs of inflammation, signs and symptoms that are confined to the gingiva, reversibility of the disease by removing the etiology, the presence of bacterial laden plaque to initiate and/or exacerbate the severity of the disease and a possible role as a precursor for attachment loss around teeth. Defining and classifying gingival diseases has not been an easy task. The tools and methods to identify gingival diseases have varied depending on the criteria used by epidemiologists, researchers, or the practicing clinician. The classification of gingival disease in this review relied upon experimental and/or epidemiological human studies that accurately and reliably assessed an underlying functional derangement that was localized to the gingiva and was reported in a peer-reviewed journal. The classification of gingival diseases that depends on dental plaque to initiate the disease process(es) has been categorized into two groups. The two categories of plaque-induced gingival diseases are those affected by local factors and those that are affected by local factors and modified by specific systemic factors found in the host. In this review, the clinical characteristics of gingival disease associated with plaque, endogenous hormone fluctuations, drugs, systemic diseases, and malnutrition were investigated.

Prevalence of beta-lactamase-producing strains among 149 anaerobic gram-negative rods isolated from periodontal pockets

In a prospective study, 47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of beta-lactamase-producing strains among oral anaerobic gram-negative rods. Predominant anaerobes were identified from two of the deepest periodontal pockets. beta-Lactamase-positive strains fulfilled to at least two of three criteria: positive nitrocefin test, penicillin Etest minimal inhibitory concentration > 1 microgram/ml, and disk diffusion synergy between amoxycillin and clavulanic acid > 10 mm. At least one beta-lactamase-producing strain was found in 53.2% of patients and 39.4% of the periodontal pockets investigated. Prominent beta-lactamase-positive species were Prevotella buccae and Prevotella intermedia (respectively 16 of 38: 42% and 18 of 52: 35% positive strains), followed by Prevotella bivia, Prevotella disiens, Prevotella denticola and Fusobacterium nucleatum (respectively 1 of 6: 17%, 1 of 10: 10%, 1 of 10: 10%, and 1 of 13: 8% positive strains). No beta-lactamase producer could be evidenced in Porphyromonas gingivalis (10 strains tested). All the beta-lactamase-positive strains with the nitrocefin test had penicillin minimal inhibitory concentrations > 1 microgram/ml with the Etest, and a strong synergy between amoxicillin and clavulanic acid was always observed.