Serum antibodies reacting with subgingival species in refractory periodontitis subjects

Microbiome at sites of gingival recession in children with Hutchinson-Gilford progeria syndrome

BACKGROUND

Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disorder with significant oral and dental abnormalities. Clinical symptoms include various features of accelerated aging such as alopecia, loss of subcutaneous fat, bone abnormalities, and premature cardiovascular disease. In addition, children with HGPS have been observed to suffer from generalized gingival recession. Whether periodontal manifestations associated with this syndrome are the results of changes in the oral flora is unknown. The present study aimed to identify the microbial composition of subgingival sites with gingival recession in children with HGPS.

METHODS

Nine children with HGPS were enrolled in this study. Plaque samples were collected from teeth with gingival recession. DNA samples were analyzed using the Human Oral Microbe Identification Microarray (HOMIM). Microbial profiles from HGPS children were compared with microbial profiles of controls from healthy individuals (n = 9) and patients with periodontal disease (n = 9).

RESULTS

Comparison of microbial compositions of HGPS samples with periodontal health samples demonstrated significant differences for two bacterial taxa; Porphyromonas catoniae and Prevotella oulora were present in children with HGPS, but not normal controls. There were statistically significant differences of 20 bacterial taxa between HGPS and periodontal disease groups.

CONCLUSIONS

Typical periodontal pathogens were not present at sites with gingival recession in HGPS children. The microbial compositions of sites of gingival recession and attachment loss in HGPS were generally more similar to those of periodontal health than periodontal disease. Species other than typical periodontal pathogens may be involved in this recession.

Lingual microbiota profiles of patients with geographic tongue

Geographic tongue (GT) is an oral mucosal lesion that affects the tongue. The association between GT and the bacterial colonization profiles of the tongue is not clear. Lingual swabs were collected from lesion sites and healthy sites of 35 patients with GT (19 males and 16 females; M_age = 54.3 ± 16.1 years) and 22 controls (12 males and 10 females; M_age = 56.3 ± 15.8 years). Bacterial DNA was extracted and sequenced by next-generation sequencing. At the phylum level, Fusobacteria were significantly less abundant, while Spirochaetes were significantly more abundant in GT patients compared to controls. At the operational taxonomic units level, multivariate analysis revealed distinct clusters for the three groups based on the lingual microbiota composition. Acinetobacter and Delftia were significantly associated with GT lesion and healthy sites. However, Microbacterium, Leptospira, Methylotenera, and Lactococcus were significantly associated with GT lesion sites. Additionally, Mogibacterium and Simonsiella were significantly associated with GT healthy sites and controls. The changes in the lingual microbiota profiles of patients with GT imply a shift in the lingual bacterial ecology. However, it remains unknown if this shift is a consequence of the lesions or of factors associated with the initiation and progression of the disease.

Antibiotic susceptibility of periodontal Enterococcus faecalis

BACKGROUND

Enterococcus faecalis may contribute to periodontal breakdown in heavily infected subgingival sites, particularly in patients responding poorly to mechanical forms of periodontal therapy. Because only limited data are available on the antimicrobial sensitivity of enterococci of subgingival origin, this study evaluates the in vitro antibiotic susceptibility of E. faecalis isolated from periodontitis patients in the United States.

METHODS

Pure cultures of 47 subgingival E. faecalis clinical isolates were each inoculated onto specially prepared broth microdilution susceptibility panels containing vancomycin, teicoplanin, and six oral antibiotics of potential use in periodontal therapy. After incubation in ambient air for 18 to 20 hours, minimal inhibitory drug concentrations were determined using applicable Clinical and Laboratory Standards Institute criteria and interpretative guidelines. The organisms were additionally evaluated for in vitro resistance to metronidazole at 4 μg/mL.

RESULTS

Periodontal E. faecalis exhibited substantial in vitro resistance to tetracycline (53.2% resistant), erythromycin (80.8% resistant or intermediate resistant), clindamycin (100% resistant to 2 μg/mL), and metronidazole (100% resistant to 4 μg/mL). In comparison, the clinical isolates were generally sensitive to ciprofloxacin (89.4% susceptible; 10.6% intermediate resistant) and 100% susceptible in vitro to ampicillin, amoxicillin/clavulanate, vancomycin, and teicoplanin.

CONCLUSIONS

Tetracycline, erythromycin, clindamycin, and metronidazole revealed poor in vitro activity against human subgingival E. faecalis clinical isolates, and would likely be ineffective therapeutic agents against these species in periodontal pockets. Among orally administered antibiotics, ampicillin, amoxicillin/clavulanate, and ciprofloxacin exhibited marked in vitro inhibitory activity against periodontal E. faecalis, and may be clinically useful in treatment of periodontal infections involving enterococci.

Impact of periodontal therapy on the subgingival microbiota of severe periodontitis: comparison between good responders and individuals with refractory periodontitis using the human oral microbe identification microarray

BACKGROUND

This study compares the changes to the subgingival microbiota of individuals with "refractory" periodontitis (RP) or treatable periodontitis (good responders [GR]) before and after periodontal therapy by using the Human Oral Microbe Identification Microarray (HOMIM) analysis.

METHODS

Individuals with chronic periodontitis were classified as RP (n = 17) based on mean attachment loss (AL) and/or >3 sites with AL ≥2.5 mm after scaling and root planing, surgery, and systemically administered amoxicillin and metronidazole or as GR (n = 30) based on mean attachment gain and no sites with AL ≥2.5 mm after treatment. Subgingival plaque samples were taken at baseline and 15 months after treatment and analyzed for the presence of 300 species by HOMIM analysis. Significant differences in taxa before and post-therapy were sought using the Wilcoxon test.

RESULTS

The majority of species evaluated decreased in prevalence in both groups after treatment; however, only a small subset of organisms was significantly affected. Species that increased or persisted in high frequency in RP but were significantly reduced in GR included Bacteroidetes sp., Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella spp., Tannerella forsythia, Dialister spp., Selenomonas spp., Catonella morbi, Eubacterium spp., Filifactor alocis, Parvimonas micra, Peptostreptococcus sp. OT113, Fusobacterium sp. OT203, Pseudoramibacter alactolyticus, Streptococcus intermedius or Streptococcus constellatus, and Shuttlesworthia satelles. In contrast, Capnocytophaga sputigena, Cardiobacterium hominis, Gemella haemolysans, Haemophilus parainfluenzae, Kingella oralis, Lautropia mirabilis, Neisseria elongata, Rothia dentocariosa, Streptococcus australis, and Veillonella spp. were more associated with therapeutic success.

CONCLUSION

Persistence of putative and novel periodontal pathogens, as well as low prevalence of beneficial species was associated with chronic refractory periodontitis.

Levels of serum immunoglobulin G specific to bacterial surface protein A of Tannerella forsythia are related to periodontal status

BACKGROUND

Tannerella forsythia (Tf) is a Gram-negative anaerobe implicated in the development of periodontal disease. Bacterial surface protein A (BspA) is a surface-expressed and -secreted protein that is recognized as an important virulence factor of Tf. This study was undertaken to determine whether Tf BspA induces an antibody response in periodontal disease. We hypothesized that serum immunoglobulin (Ig)G antibody levels against BspA correlate with the disease of patients.

METHODS

Sera were obtained from 100 patients with cardiac disorders and periodontal disease and 73 patients who experienced myocardial infarction but were periodontally healthy. Sera samples were assayed for anti-BspA antibody (total IgG and IgG subtypes) by enzyme-linked immunosorbent assay (ELISA). Antibody levels were measured in ELISA units by using an arbitrary patient as a standard.

RESULTS

A negative correlation was found with BspA-specific total IgG antibody titers and the severity of disease measured as the clinical attachment level (CAL) when healthy and diseased groups were analyzed separately (healthy group: [-0.23, correlation value] Student's t value [73 degrees of freedom] = 1.99; P = 0.05; diseased group: [-0.21] t [100 degrees of freedom] = 2.12; P = 0.03]). However, there was a positive correlation ([0.18 correlation value] Student's t value [173 degrees of freedom] = 2.39; P = 0.017) when healthy and diseased groups were combined. A strong positive correlation ([0.338 correlation value] Student's t value [173 degrees of freedom] = 4.69; P <0.0001) between the BspA-specific IgG titers and periodontal probing depth was observed when healthy and disease groups were combined.

CONCLUSIONS

Data demonstrated that antibodies to Tf BspA were elicited in patients with periodontal disease, and antibody levels were associated with the disease severity. Furthermore, data suggested that anti-BspA IgG might have a protective function in periodontal disease by minimizing the loss of tooth attachment tissue.

Periodontal disease as a risk marker in coronary heart disease and chronic kidney disease

PURPOSE OF REVIEW

More than half a million Americans die each year from coronary heart disease (CHD), 26 million suffer from chronic kidney disease (CKD), and a large proportion have periodontal disease, a chronic infection of the tissues surrounding teeth. Chronic inflammation contributes to CHD and CKD occurrence and progression, and periodontal disease contributes to the cumulated chronic systemic inflammatory burden. This review examines recent evidence regarding the role of periodontal disease in CHD and CKD.

RECENT FINDINGS

Periodontal pathogens cause both local infection and bacteremia, eliciting local and systemic inflammatory responses. Periodontal disease is associated with the systemic inflammatory reactant C-reactive protein (CRP), a major risk factor for both CHD and CKD. Nonsurgical periodontal disease treatment is shown to improve periodontal health, endothelial function, levels of CRP, and other inflammatory markers. Evidence for the association of periodontal disease with CKD consists of a small body of literature represented mainly by cross-sectional studies. No definitive randomized controlled trials exist with either CHD or CKD as primary endpoints.

SUMMARY

Recent evidence links periodontal disease with CHD and CKD. Adding oral health self-care and referral for professional periodontal assessment and therapy to the repertoire of medical care recommendations is prudent to improve patients' oral health and possibly reduce CHD and CKD risk.

Determinants of serum IgG responses to periodontal bacteria in a nationally representative sample of US adults

AIM

To assess the distribution of elevated antibody titres to multiple periodontal bacteria, including established/putative pathogens and health-related species, by selected demographic, behavioural, and oral- and general health-related characteristics.

METHODS

Data from 8153 >or=40-year-old participants from the third National Health and Nutrition Examination Survey were used, including 1588 edentulous individuals. We used checkerboard immunoblotting to assess serum IgG levels to 19 periodontal species. Thresholds for elevated antibody responses were defined for each species using the 90th percentile titre in periodontal healthy participants, using two alternative definitions of periodontitis.

RESULTS

Edentulous individuals showed lower antibody responses than dentate participants, notably for titres to "red complex" species and Actinobacillus actinomycetemcomitans. Elevated titres to Porphyromonas gingivalis were twice as prevalent in participants with periodontitis than in periodontal healthy individuals. Non-Hispanic blacks and Mexican-Americans were more likely to display elevated titres for P. gingivalis compared with non-Hispanic whites (22.9%versus 19.4%versus 9.5%). Current smokers were significantly less likely to exhibit high titres to multiple bacteria than never smokers.

CONCLUSION

Demographic, behavioural, and oral- and general health-related characteristics were strong determinants of systemic antibody responses to periodontal bacteria in a nationally representative sample of US adults.

Comparisons of subgingival microbial profiles of refractory periodontitis, severe periodontitis, and periodontal health using the human oral microbe identification microarray

BACKGROUND

This study compared the subgingival microbiota of subjects with refractory periodontitis (RP) to those in subjects with treatable periodontitis (GRs = good responders) or periodontal health (PH) using the Human Oral Microbe Identification Microarray (HOMIM).

METHODS

At baseline, subgingival plaque samples were taken from 47 subjects with periodontitis and 20 individuals with PH and analyzed for the presence of 300 species by HOMIM. The subjects with periodontitis were classified as having RP (n = 17) based on mean attachment loss (AL) and/or more than three sites with AL >or=2.5 mm after scaling and root planing, surgery, and systemically administered amoxicillin and metronidazole or as GRs (n = 30) based on mean attachment gain and no sites with AL >or=2.5 mm after treatment. Significant differences in taxa among the groups were sought using the Kruskal-Wallis and chi(2) tests.

RESULTS

More species were detected in patients with disease (GR or RP) than in those without disease (PH). Subjects with RP were distinguished from GRs or those with PH by a significantly higher frequency of putative periodontal pathogens, such as Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Campylobacter gracilis, Eubacterium nodatum, Selenomonas noxia, Tannerella forsythia (previously T. forsythensis), Porphyromonas gingivalis, Prevotella spp., Treponema spp., and Eikenella corrodens, as well as unusual species (Pseudoramibacter alactolyticus, TM7 spp. oral taxon [OT] 346/356, Bacteroidetes sp. OT 272/274, Solobacterium moorei, Desulfobulbus sp. OT 041, Brevundimonas diminuta, Sphaerocytophaga sp. OT 337, Shuttleworthia satelles, Filifactor alocis, Dialister invisus/pneumosintes, Granulicatella adiacens, Mogibacterium timidum, Veillonella atypica, Mycoplasma salivarium, Synergistes sp. cluster II, and Acidaminococcaceae [G-1] sp. OT 132/150/155/148/135) (P <0.05). Species that were more prevalent in subjects with PH than in patients with periodontitis included Actinomyces sp. OT 170, Actinomyces spp. cluster I, Capnocytophaga sputigena, Cardiobacterium hominis, Haemophilus parainfluenzae, Lautropia mirabilis, Propionibacterium propionicum, Rothia dentocariosa/mucilaginosa, and Streptococcus sanguinis (P <0.05).

CONCLUSION

As determined by HOMIM, patients with RP presented a distinct microbial profile compared to patients in the GR and PH groups.

Clinical and microbiological changes associated with the use of combined antimicrobial therapies to treat "refractory" periodontitis

BACKGROUND

The present investigation examined clinical and microbial changes after a combined aggressive antimicrobial therapy in subjects identified as "refractory" to conventional periodontal therapy.

METHOD

Fourteen subjects were identified as "refractory" based on full-mouth mean attachment loss and/or >3 sites with attachment loss > or =3 mm following scaling and root planing (SRP), periodontal surgery and systemic antibiotics. After baseline monitoring, subjects received SRP, locally delivered tetracycline at pockets > or =4 mm, systemically administered amoxicillin (500 mg, t.i.d. for 14 days)+metronidazole (250 mg, t.i.d. for 14 days) and professional removal of supragingival plaque weekly for 3 months. Subjects were monitored clinically every 3 months post-therapy for 2 years. Subgingival plaque samples were taken at the same time points from the mesial aspect of each tooth and the levels of 40 subgingival taxa were determined using checkerboard DNA-DNA hybridization. Mean levels of each species were averaged within a subject at each visit. Significance of changes in clinical and microbiological parameters over time were evaluated using the Friedman or Wilcoxon signed ranks test.

RESULTS

On average, subjects showed significant improvements in all clinical parameters after therapy. Mean (+/-SEM) full-mouth pocket depth reduction was 0.83+/-0.13 mm and mean attachment level "gain" was 0.44+/-0.12 at 24 months. Clinical improvement was accompanied by major reductions in multiple subgingival species during the first 3 months of active therapy that were maintained for most species to the last monitoring visit. Reductions occurred for three Actinomyces species, "orange complex" species including Campylobacter showae, Eubacterium nodatum, three Fusobacterium nucleatum subspecies, Peptostreptococcus micros, Prevotella intermedia as well as the "Streptococcus milleri" group, Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedus. Subjects differed in their response to therapy; six modest response subjects exhibited less attachment level gain and were characterized by reductions in the microbiota from baseline to 3 months, but re-growth of many species thereafter.

CONCLUSIONS

The combined antibacterial therapy was successful in controlling disease progression in 14 "refractory" periodontitis subjects for 2 years.

Systemic anti-infective periodontal therapy. A systematic review

BACKGROUND

Periodontal diseases are infections and thus systemically administered antibiotics are often employed as adjuncts for their control. There are conflicting reports as to whether these agents provide a therapeutic benefit.

RATIONALE

The purpose of this systematic review is to determine whether systemically administered antibiotics improve a primary clinical outcome measure, periodontal attachment level change.

FOCUSED QUESTION

In patients with periodontitis, what is the effect of systemically administered antibiotics as compared to controls on clinical measures of attachment level?

SEARCH PROTOCOL

The Pub/Med database was searched from 1966 to May 2002. Searches were limited to human studies published in English. Hand searches were performed on the Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. References in relevant papers and review articles were also examined.

SELECTION CRITERIA

INCLUSION CRITERIA

Trials were selected if they met the following criteria: randomized controlled clinical trials, quasi-experimental studies, and cohort studies of > 1 month duration with a comparison group; subjects with aggressive, chronic, or recurrent periodontitis and periodontal abscess; use of a single or a combination of systemically administered antibiotics(s) versus non-antibiotic therapy; and a primary outcome of mean attachment level change (AL).

EXCLUSION CRITERIA

Studies involving the use of low-dose doxycycline, combinations of locally plus systemic antibiotics, or where the control group included a systemically administered antibiotic were excluded.

DATA COLLECTION AND ANALYSIS

A mean difference in AL between groups was available for all papers used in the meta-analysis. A standard deviation (SD) for the difference was used if provided or calculated from the SD or standard error of the mean (SEM) when provided for single measurements. Data were subset by antibiotic employed, type of adjunctive therapy, and disease type. Results were assessed with both fixed-effects and random-effects models.

MAIN RESULTS

1. Twenty-nine studies, 26 RCTs and 3 quasi-experimental (36 comparisons), met the entry criteria. Total study population, both control and test groups, was estimated at over 1,200. 2. Twenty-two studies (27 comparisons) were used in the meta-analysis, evaluating if the antibiotics provided a consistent benefit in mean AL change for different patient populations, for different therapies, and for different antibiotics. 3. For the majority of the comparisons, systemically administered antibiotics exhibited a more positive attachment level change than the control group in the study. The combined results were statistically significant (P < 0.001). 4. The systemic antibiotics were uniformly beneficial in providing an improvement in AL when used as adjuncts to scaling and root planing (SRP) and were consistently beneficial, although of borderline significance, when used as adjuncts to SRP plus surgery or as a stand alone therapy. 5. When examining the effects of individual or combinations of antibiotics, it was found that there were statistically significant improvements in AL for tetracycline, metronidazole, and an effect of borderline statistical significance for the combination of amoxicillin plus metronidazole. 6. Improvements in mean AL were consistent for both chronic and aggressive periodontitis subjects, although the aggressive periodontitis patients benefited more from the antibiotics.

REVIEWERS' CONCLUSIONS

1. The use of systemically administered adjunctive antibiotics with and without SRP and/or surgery appeared to provide a greater clinical improvement in AL than therapies not employing these agents. 2. The data supported similar effect sizes for the majority of the antibiotics; therefore, the selection for an individual patient has to be made based on other factors. 3. Due to a lack of sufficient sample size for many of the antibiotics tested, it is difficult to provide guidance as to the more effective ones.

Streptococci and Actinomyces induce antibodies which cross react with epithelial antigens in periodontitis

Perturbation of epithelial structure is a prominent but poorly understood feature of the immunopathological response to bacterial antigens which characterizes the destructive lesion of periodontitis. Western analysis of sera from 22 patients with periodontitis detected multiple antigens in extracts of epithelial cells whereas sera from 12 periodontally healthy subjects displayed only trace reaction with epithelial antigens. To investigate a possible relationship between the bacterial flora adjacent to diseased sites and the presence of antibodies reactive with epithelium, subgingival plaque samples were taken from deep periodontal pockets and cultured anaerobically. Gram positive bacteria containing antigens cross-reactive with epithelial cells were reproducibly isolated by probing membrane colony-lifts with affinity-isolated (epithelium-specific) antibodies and identified by 16S rDNA sequence homology as streptococci (S. mitis, S. constellatus and two S. intermedius strains) and Actinomyces (A. georgiae, and A. sp. oral clone). Conversely, when serum from patients with periodontitis was absorbed with the captured bacterial species the number of epithelial antigens recognized was specifically reduced. It was concluded that development of cross-reactive antibodies related to these organisms may contribute to perturbation of the epithelial attachment to the tooth and the progression of periodontitis. These autoreactive antibodies could also be a contributing factor in other diseases affecting epithelia.

Preterm low birth weight and periodontal disease among African Americans

African Americans consistently experience higher rates of preterm and low birth weight (LBW) deliveries than do whites. LBW and preterm infants are more likely to die before their first birthday and survivors may suffer from a number of health problems. Therefore, identification of modifiable risk factors for preterm deliveries and LBW has considerable public health significance. Pregnant women's poor periodontal healtlh is emerging as one such factor. Maternal clinical periodontal status and bacteriologic and immunologic profiles related to periodontal disease have been associateted with risk of fetal growth and preterm LBW, and periodontal treatment during pregnancy has reduced the incidence of preterm deliveries. This article reviews the literature on the above association and presents data from a previously published prospective study of predominantly African Americans to show that preterm LBW deliveries are associated with higher midtrimester maternal serum antibody levels against Porphyromonas gingivalis.

Serum markers of periodontal disease status and inflammation in hemodialysis patients

BACKGROUND

Hemodialysis (HD) patients face a 25% annual mortality rate, with 50% of reported deaths attributed to cardiovascular disease. All-cause and cardiovascular mortality correlate with such acute-phase proteins as C-reactive protein (CRP). Hepatic CRP synthesis is upregulated by inflammation; however, elevated CRP values frequently are found in the absence of apparent infection or inflammation. Because destructive periodontal diseases have been associated with elevated CRP levels, we questioned whether destructive periodontal diseases could contribute to elevated CRP values in HD populations.

METHODS

Sera from 86 consecutive dentate HD patients were assayed for levels of immunoglobulin G (IgG) antibody to six periodontal species by means of an enzyme-linked immunosorbent assay.

RESULTS

CRP values for the subject population ranged from less than 6.9 to 159 mg/L (median, 8.2 mg/L). Univariate comparisons between subjects with or without elevated CRP levels (>10 mg/L) showed that CRP level elevation was associated significantly (P < 0.05) with greater doses of human recombinant erythropoietin and lower levels of hemoglobin, serum iron, transferrin saturation (TSat), albumin averaged over the 3 preceding months, total cholesterol, and triglycerides. Log serum IgG antibody levels to Porphyromonas gingivalis also were significantly greater in the group with elevated CRP levels (P = 0.013). Subsequent multivariate logistic regression showed that log serum antibody levels to P gingivalis remained significant (P = 0.02) after controlling for nonperiodontal sources of elevated CRP, hemoglobin, TSat, and triglyceride values.

CONCLUSION

These results suggest that elevated levels of IgG antibody to bacterial species associated with destructive periodontal diseases are associated with elevated CRP values in HD populations.

Antibody-based diagnostic for 'refractory' periodontitis

OBJECTIVE

About 10-15% of US adults are 'refractory' to therapy for chronic periodontitis. Recently, studies suggest that these patients have elevated lysine decarboxylase activity in the sulcular microbiota. The aim of this study was to determine whether an elevated IgG antibody response to lysine decarboxylase, alone or with antibody to other bacterial antigens and baseline clinical measurements, would predict 'refractory' patients with high accuracy.

METHODS

Chronic periodontitis patients were treated using scaling and root planing (SRP) followed by maintenance SRP and 3-monthly re-examinations. If there was a loss of mean full mouth attachment or more than three sites appeared with > 2.5 mm new loss within a year, the subjects were re-treated (modified Widman flap surgery and systemically administered tetracycline). If attachment loss as above recurred, the subjects were 'refractory'. Baseline clinical measurements and specific antibody responses were used in a logistic regression model to predict 'refractory' subjects.

RESULTS

Antibody to a peptide portion of lysine decarboxylase (HKL-Ab) and baseline bleeding on probing (BOP) prevalence measurements predicted attachment loss 3 months after initial therapy [pIAL = loss (0) or gain (1)]. IgG antibody contents to a purified antigen from Actinomyces spp. (A-Ab) and streptococcal d-alanyl glycerol lipoteichoic acid (S-Ab) were related in 'refractory' patients (R2 = 0.37, p < 0.01). From the regression equation, the relationship between the antibodies was defined as linear (pLA/S-Ab = 0) or non-linear pLA/S-Ab = 1). Using pLA/S-Ab, pIAL and age, a logistic regression equation was derived from 48 of the patients. Of 59 subjects, 37 had 2-4 mm attachment loss and were assigned as 'refractory' or successfully treated with 86% accuracy.

CONCLUSION

HKL-Ab facilitated an accurate prediction of therapeutic outcome in subjects with moderate periodontitis.

Serum IgG antibody response to periodontal pathogens in minority populations: relationship to periodontal disease status and progression

Differences in periodontal disease prevalence, severity, subgingival microflora and host immune response have been reported for various ethnic/racial groups, which implies that risk factors for destructive periodontal disease progression may also vary in these populations. As it is possible that these differences may be due to confounding variables other than ethnicity/race, we have measured serum IgG antibody response to six periodontal pathogens, and compared these data with microbiological, clinical and demographic parameters in three urban minority populations. The study population consisted of 23 Asiatic, 48 African-American and 37 Hispanic subjects, who were resident in the greater New York region. Clinical indices that were recorded included pocket depth, attachment level, gingival erythema, bleeding upon probing, suppuration and supragingival plaque. Attachment level measurements were taken twice at each visit, and the difference between the means of pairs of measurements taken at baseline and two months later was used to determine disease progression. Subgingival microbiological species were identified and enumerated using DNA-DNA checkerboard hybridization. Serum IgG antibody levels to Actinobacillus actinomycetemcomitans serotyopes a and b, Bacteroides forsythus, Campylobacter rectus, Porphyromonas gingivalis and Prevotella intermedia were measured by enzyme-linked immunosorbant assay (ELISA). Mean serum IgG antibody to P. gingivalis was found to be higher in the African-American group, while IgG antibody to B. forsythus was lower in the Hispanic group. However, the African-American group also had greater mean probing depth, attachment loss, number of missing teeth and numbers of individuals within the unskilled occupational group. When the data were analyzed by occupational status, mean serum IgG antibody to P. gingivalis increased from professional to skilled to unskilled groups. For the entire study population, prior disease and subsequent attachment loss were associated with elevated serum IgG antibody to P. gingivalis. Increasing pocket depth, attachment level, gingival erythema and age were also positively correlated with serum IgG antibody to P. gingivalis, but not with serum IgG antibody to the other five subgingival species. No correlation was found between whole-mouth bacterial levels and homologous serum IgG antibody levels. These results suggest that elevated serum IgG antibody to P. gingivalis reflects destructive periodontal disease status, and may be considered a risk factor for disease progression in these ethnic/racial populations. In addition, although differences in serum IgG antibody profiles to subgingival species were found among the three ethnic/racial groups, environmental and socioeconomic variables may have a greater influence on serum IgG antibody levels in these populations.

Women's health issues and their relationship to periodontitis

BACKGROUND

The emergence of sex-specific associations between periodontitis and certain systemic disorders has prompted researchers to investigate the possibility of associations between periodontitis and specific women's health issues. The authors review the potential relationships between periodontitis and hormonal changes and their ramifications in regard to pregnancy outcomes, cardiovascular disease, or CVD, and osteoporosis.

METHODS

Changes in hormone levels, such as those that occur during puberty, pregnancy, menstruation and menopause, as well as those that occur with the use of hormonal supplements, have long been associated with the development of gingivitis. Furthermore, bacterial anaerobes have been found to change during the normal hormonal cycle. In periodontitis, the inflammatory response results in ulceration of the gingivae and the subsequent entry of bacterial cells, bacterial products, peptidoglycan fragments and hydrolytic enzymes into the systemic circulation. The result is a systemic response of increased cytokines and biological mediators, as well as increased levels of serum antibodies.

RESULTS

Some researchers have found that pregnant women with periodontitis were 7.5 times more likely to have a preterm low-birth-weight infant than were control subjects. Other researchers reported that the risk of preterm birth was directly related to the severity of periodontitis. Similarly, researchers have linked periodontitis to CVD. Many studies have indicated that estrogen exerts a protective effect against CVD development, and much evidence suggests that when hormone replacement therapy is administered to postmenopausal women, this effect continues. A relationship between periodontitis and osteoporosis has been established, such that more clinical attachment loss has been noted in osteoporotic people.

CONCLUSIONS

The literature suggests that more sex-specific research is essential to determine the strategies needed to prevent and treat adverse pregnancy outcomes, CVD and osteoporosis through hormone modification and periodontitis control.

CLINICAL IMPLICATIONS

Dentists must assume greater responsibility for the overall health of their patients, and acquire knowledge of relevant systemic conditions to interact meaningfully with medical colleagues.

Subgingival microbial profiles in refractory periodontal disease

BACKGROUND/AIM

The purpose of the present investigation was to examine subgingival microbial profiles associated with refractory periodontitis and to seek such profiles in periodontally healthy, periodontally well-maintained elder and untreated periodontitis subjects.

METHODS

36 subjects were defined as refractory on the basis of further attachment loss after scaling and root planing, surgery and systemically administered antibiotics. A total of 890 subgingival plaque samples (mean/subject=24.7) were taken from the mesial aspect of each tooth in each subject at baseline and individually processed for their content of 40 subgingival taxa using checkerboard DNA-DNA hybridization. Cluster analysis was performed on mean within subject species counts using the chord coefficient and an average unweighted linkage sort. Significant differences among clusters for individual and complexes of species were sought using the Kruskal Wallis test. The microbial profiles of the refractory subjects were compared with those of 27 periodontally healthy subjects (n plaque samples=708), 35 periodontally well-maintained elder subjects (n plaque samples=801) and 115 untreated adult periodontitis subjects (n plaque samples=2871).

RESULTS

28 of 36 refractory subjects fell into 4 clusters with >29% similarity. 10 of 40 species and 4 of 7 complexes differed significantly among clusters. Profile (Cluster) I (n=4) was characterized by high proportions of "yellow" and "green" complex species, profile II (n=3) by low total counts and high proportions of "orange" and "purple" complex species, profile III (n=9) by high total counts and counts of Actinomyces and "purple" complex species, profile IV (n=12) by high proportions of "red" and "orange" complex species. The mean profiles of each cluster were subjected to cluster analysis with microbial data from 4380 (mean 24.7) baseline subgingival plaque samples from 27 periodontally healthy, 35 treated, well-maintained elders and 115 untreated adult periodontitis subjects. 12 clusters were formed with >41% similarity. 3 of the refractory profiles were detected in 3 cluster groups. Profile II in a cluster of 1 healthy, 1 elder and 4 untreated periodontitis subjects; profile III in a cluster of 1 healthy, 2 elder and 12 periodontitis subjects; Profile IV, with 1 healthy and 5 untreated periodontitis subjects. The profile not detected in non refractory subjects was dominated by Streptococcus species. 9 clusters did not harbor refractory profiles. 11.1% of healthy, 8.6% of elder and 18.3% of periodontitis subjects were in clusters exhibiting refractory microbial profiles.

CONCLUSIONS

4 subgingival microbial profiles were detected among refractory subjects. "Refractory microbial profiles" could be detected in subjects who had not yet exhibited refractory disease.

Periodontitis and diabetes interrelationships: role of inflammation

Diabetes mellitus is a systemic disease with several major complications affecting both the quality and length of life. One of these complications is periodontal disease (periodontitis). Periodontitis is much more than a localized oral infection. Recent data indicate that periodontitis may cause changes in systemic physiology. The interrelationships between periodontitis and diabetes provide an example of systemic disease predisposing to oral infection, and once that infection is established, the oral infection exacerbates systemic disease. In this case, it may also be possible for the oral infection to predispose to systemic disease. In order to understand the cellular/molecular mechanisms responsible for such a cyclical association, one must identify common physiological changes associated with diabetes and periodontitis that produce a synergy when the conditions coexist. A potential mechanistic link involves the broad axis of inflammation, specifically immune cell phenotype, serum lipid levels, and tissue homeostasis. Diabetes-induced changes in immune cell function produce an inflammatory immune cell phenotype (upregulation of proinflammatory cytokines from monocytes/polymorphonuclear leukocytes and downregulation of growth factors from macrophages). This predisposes to chronic inflammation, progressive tissue breakdown, and diminished tissue repair capacity. Periodontal tissues frequently manifest these changes because they are constantly wounded by substances emanating from bacterial biofilms. Diabetic patients are prone to elevated low density lipoprotein cholesterol and triglycerides (LDL/TRG) even when blood glucose levels are well controlled. This is significant, as recent studies demonstrate that hyperlipidemia may be one of the factors associated with diabetes-induced immune cell alterations. Recent human studies have established a relationship between high serum lipid levels and periodontitis. Some evidence now suggests that periodontitis itself may lead to elevated LDL/TRG. Periodontitis-induced bacteremia/endotoxemia has been shown to cause elevations of serum proinflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha), which have been demonstrated to produce alterations in lipid metabolism leading to hyperlipidemia. Within this context, periodontitis may contribute to elevated proinflammatory cytokines/serum lipids and potentially to systemic disease arising from chronic hyperlipidemia and/or increased inflammatory mediators. These cytokines can produce an insulin resistance syndrome similar to that observed in diabetes and initiate destruction of pancreatic beta cells leading to development of diabetes. Thus, there is potential for periodontitis to exacerbate diabetes-induced hyperlipidemia, immune cell alterations, and diminished tissue repair capacity. It may also be possible for chronic periodontitis to induce diabetes.

The association between Porphyromonas gingivalis-specific maternal serum IgG and low birth weight

BACKGROUND

In Alabama, low birth weight (LBW) infants are about 20 times more likely to die before their first birthday compared to normal birth weight infants. While the rate of LBW has been consistently higher among African Americans compared to whites, there has been a gradual increase in LBW for both African Americans and whites over the last 15 years. In an attempt to identify modifiable risk factors for LBW, we have previously reported that a pregnant woman's poor periodontal health may be an independent risk factor for low birth weight.

METHODS

A predominantly African American and socioeconomically homogeneous group of 448 women was followed from the second trimester of their first pregnancy. Thirty-nine LBW cases were observed at the end of follow-up. Using 17 preterm LBW cases and 63 randomly selected controls from the above cohort, the periodontal pathogen-specific maternal serum IgG levels during the second trimester of pregnancy were evaluated in relation to birth weight of the infant, while controlling for known risk factors for LBW.

RESULTS

Porphyromonas gingivalis (P.g.)-specific maternal serum IgG levels were higher in the LBW group (mean 58.05, SE = 20.00 microg/ml) compared to the normal birth weight (NBW) group (mean 13.45, SE = 3.92 microg/ml; P= 0.004). Women with higher levels of P.g.-specific IgG had higher odds of giving birth to LBW infants (odds ratio [OR] = 4.1; 95% confidence interval [CI] for odds ratio = 1.3 to 12.8). This association remained significant after controlling for smoking, age, IgG levels against other selected periodontal pathogens, and race.

CONCLUSIONS

Low birth weight deliveries were associated with a higher maternal serum antibody level against P. gingivalis at mid-trimester.

Pathophysiological relationships between periodontitis and systemic disease: recent concepts involving serum lipids

Periodontitis has been traditionally regarded as a chronic inflammatory oral infection. However, recent studies indicate that this oral disease may have profound effects on systemic health. The search for cellular/molecular mechanisms linking periodontitis to changes in systemic health and systemic physiology has resulted in the evolution of a new area of lipid research establishing linkages between existing multidisciplinary biomedical literature, recent observations concerning the effects of serum lipids on immune cell phenotype/function, and a heightened interest in systemic responses to chronic localized infections. There appears to be more than a casual relationship between serum lipid levels and systemic health (particularly cardiovascular disease, diabetes, tissue repair capacity, and immune cell function), susceptibility to periodontitis, and serum levels of pro-inflammatory cytokines. In terms of the potential relationship between periodontitis and systemic disease, it is possible that periodontitis-induced changes in immune cell function cause metabolic dysregulation of lipid metabolism through mechanisms involving proinflammatory cytokines. Sustained elevations of serum lipids and/or pro-inflammatory cytokines may have a serious negative impact on systemic health. The purpose of this paper is to present the background, supporting data, and hypotheses related to this concept. As active participants in this emerging and exciting area of investigation, we hope to stimulate interest and awareness among biomedical scientists and practitioners.