Association between early preterm birth and periodontitis according to USA and European consensus definitions.

OBJECTIVE: Prospective case-control study assessing the association between maternal periodontitis according to the recently issued USA and European consensus definitions and early preterm delivery (<35 weeks gestation). Cases were women delivering between 22 and 34(6/7) weeks of gestation (n = 84) and controls were women delivering at term (≥ 37 weeks) (n = 345). METHODS: Periodontal examination at the immediate postpartum period identified periodontitis according to both consensus definitions. A multivariate logistic model was used to assess the association between early preterm delivery and the presence of periodontitis adjusted for confounders. RESULTS: All women had periodontitis by the European consensus definitions. When using the USA definitions, more cases had severe periodontitis than controls (34.5% vs. 17.72%); p = 0.003. After adjustment for main confounders, the association between severe (OR: 2.38; 95% CI: 1.36-4.14) periodontitis and early preterm delivery persisted. The only other independent factor associated with early preterm delivery was vaginal bleeding during pregnancy. CONCLUSIONS: Early preterm delivery is associated with periodontitis when the USA consensus definitions are used. The European definitions revealed inadequate for the study population because of the lack of discrimination power.

Predictive value of clinical and microbiological parameters for the treatment outcome of scaling and root planing.

OBJECTIVES: To compare the clinical and microbiological outcome of non-surgical periodontal therapy after 6 months with data obtained after hygienic phase or 6 weeks after completion of non-surgical therapy, in order to evaluate the value of clinical and microbiological parameters to predict treatment success. MATERIAL AND METHODS: Clinical and microbiological data were available from 271 sites in 10 systemically healthy non-smokers with moderate-to-advanced chronic periodontal disease (24-32 sites per individual). Subgingival plaque samples were tested for the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Tannerella forsythensis and Treponema denticola using RNA probes. RESULTS: Stepwise multiple linear regression analysis revealed a significant impact of the number of sites with visible plaque index >1 after hygienic phase on the bleeding tendency of a subject at month 6 (p<0.01). Furthermore, an association could be demonstrated between the number of residual pockets (PD>3 mm) 6 months after therapy and the number of bleeding sites and suppurating sites after hygienic phase (p=0.016). Six weeks after therapy, the mean total bacterial loads had a significant impact on the bleeding tendency of a subject at month 6 (p<0.01). Although the average numbers of sites with persisting P. gingivalis, A. actinomycetemcomitans, T. forsythensis and T. denticola seemed to be very similar 6 weeks and 6 months after therapy, large variations were noted between subjects, and therefore the microbiological status of a subject at week 6 could not predict the status at month 6. CONCLUSIONS: The present study showed a limited potential of microbiological tests, performed after hygienic phase or shortly after non-surgical periodontal therapy, to predict the clinical outcome 6 months later, but confirmed the importance of an establishment of perfect oral hygiene before non-surgical therapy.

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.

Anti-plaque agents in the prevention of biofilm-associated oral diseases.

The prevention of dental caries and periodontal diseases is targeted at the control of dental plaque. In this context, chemical agents could represent a valuable complement to mechanical plaque control. The active agents should prevent biofilm formation without affecting the biological equilibrium within the oral cavity. Depending on the goals of the preventive measures, various strategies may be considered. Anti-plaque agents with properties other than bactericidal or bacteriostatic activities may be used in primary prevention. In this approach, a modest antiplaque effect may be sufficient or even desirable, as it would decrease the side effects of the active agent. Antimicrobial agents are best indicated in secondary and tertiary prevention, as the objectives are to restore health and to prevent disease recurrence. The rational is to prevent or delay subgingival recolonization by pathogenic micro-organisms. The development of in vitro oral biofilm models certainly represents a major advance for studying and testing oral anti-plaque agents in recent years. The results of these studies have shown that chlorhexidine, hexetidine, delmopinol, amine fluoride/stannous fluoride, triclosan, phenolic compounds, among others, may inhibit biofilm development and maturation as well as affect bacterial metabolism.

Development and applications of injectable poly(ortho esters) for pain control and periodontal treatment.

Poly(ortho esters) with a low glass transition temperature are semi-solid materials so that therapeutic agents can be incorporated at room temperature, without the use of solvents, by a simple mixing procedure. When molecular weights are limited to < 5 kDa, such materials are directly injectable using a needle size no larger than 22 gauge. Somewhat hydrophilic polymers can be produced by using the diketene acetal 3,9-diethylidene-2,4,8,10-tetraoxaspiro[5.5]undecane and triethylene glycol (TEG), while hydrophobic materials can be produced by using the diketene acetal and 1,10-decanediol. Molecular weight can be reproducibly controlled by using an excess of the diol, or by use of an alcohol that acts as a chain-stopper. Erosion rates can be controlled by varying the amount of latent acid incorporated into the polymer backbone. Toxicology studies using the TEG polymer have been completed and have shown that the polymer is non-toxic. Toxicology studies using the decanediol polymer are underway. Development studies using the TEG polymer aimed at providing a sustained delivery of an analgesic agent to control post-surgical pain are under development and human clinical trials using the decanediol polymer for the treatment of periodontitis are also underway.

Bioerodible injectable poly(ortho ester) for tetracycline controlled delivery to periodontal pockets: preliminary trial in humans.

The semisolid consistency of poly(ortho esters) (POEs) containing tetracycline free base allows direct injection in the periodontal pocket and shows sustained and almost constant in vitro release in phosphate buffer, pH 7.4 at 37 degrees C, for up to 14 days. Total polymer degradation concomitant with drug release was obtained. Formulations containing 10% or 20% (wt/wt) tetracycline were evaluated in a panel of 12 patients suffering from severe and recurrent periodontitis. In the first trial including 6 patients, single-rooted teeth and molar teeth with furcations were treated immediately after scaling and root planing. Patients tolerated both formulations well, experienced no pain during application, and showed no signs of irritation or discomfort during the observation period. However, retention of the formulation was minimal in this first study. An improved clinical protocol followed in the second study (stopping bleeding after scaling and root planning) prolonged the retention of the formulations in the inflamed periodontal pockets. For up to 11 days, tetracycline concentrations in the gingival crevicular fluid were higher than the minimum inhibitory concentration of tetracycline against most periodontal pathogens.

[Periodontal status among the population of Geneva, Vaud and Neuchâtel]. / Situation parodontale de la population des cantons de Genève, Vaud et Neuchâtel.

The aim of the present study was to evaluate the periodontal status among the population of Geneva, Vaud and Neuchâtel. A representative sample of the population was selected on the basis of age, sex and location. The rate of participation was 51%. In total, 268 subjects were examined; this corresponds to 1:4000 inhabitants. The results showed that a majority of the subjects presented signs of inflamed gingiva. Moderate periodontitis affected a large proportion of the population, whereas severe periodontitis affected only a small percentage of subjects. We observed that the severity of periodontal destruction increased with age and there was no difference between both sexes. The findings revealed that most of the periodontal treatment needs could be provided by general dentists. Complex treatment needs were limited in extent.

Porphyromonas gingivalis gingipain-R enhances interleukin-8 but decreases gamma interferon-inducible protein 10 production by human gingival fibroblasts in response to T-cell contact.

Proteases produced by Porphyromonas gingivalis, an oral pathogen, are considered important virulence factors and may affect the responses of cells equipped with proteinase-activated receptors. The aim of this study was to investigate the effect of the arginine-specific cysteine protease gingipain-R produced by P. gingivalis on chemokine production by human gingival fibroblasts (HGF) and the effect of gingipain-R treatment on the subsequent contact-dependent activation of HGF by T cells. HGF incubated in the presence of purified 47-kDa gingipain-R showed increased levels of interleukin-8 (IL-8) mRNA. Cyclooxygenase-2 (COX-2) mRNA was also induced. Further exposure of HGF to activated T cells resulted in the dose- and time-dependent enhancement of IL-8 transcription and release. T-cell membrane-bound tumor necrosis factor (TNF) was the ligand inducing IL-8 production by HGF, since TNF neutralization abrogated HGF responses to T-cell contact. The enhanced IL-8 release was due, at least in part, to prostaglandin-E(2) production, which was mostly blocked by indomethacin. Gingipain-R proteolytic activity was required since heat inactivation, specific synthetic protease inhibitors, and the natural substrate competitor histatin 5 abrogated its effects. The enhanced production of IL-8 in response to T-cell contact was specific since monocyte chemotactic protein-1 (MCP-1) production was unaffected while interferon-gamma-inducible protein-10 (IP-10) was inhibited. The sum of these activities may result in the recruitment of differential cell types to sites of inflammation since IL-8 preferentially recruits neutrophils and IP-10 attracts activated T cells and may be relevant to the pathogenesis of periodontitis.

Chitosan as tear substitute: a wetting agent endowed with antimicrobial efficacy.

A cationic biopolymer, chitosan, is proposed for use in artificial tear formulations. It is endowed with good wetting properties as well as an antibacterial effect that are desirable in cases of dry eye, which is often complicated by secondary infections. Solutions containing 0.5% w/v of a low molecular weight (M(w)) chitosan (160 kDa) were assessed for antibacterial efficacy against E. coli and S. aureus by using the usual broth-dilution technique. The in vitro evaluation showed that concentrations of chitosan as low as 0.0375% still exert a bacteriostatic effect against E. coli. Minimal inhibitory concentration (MIC) values of chitosan were calculated to be as low as 0.375 mg/ml for E. coli and 0.15 mg/ml for S. aureus. Gamma scintigraphic studies demonstrated that chitosan formulations remain on the precorneal surface as long as commonly used commercial artificial tears (Protagent collyrium and Protagent-SE unit-dose) having a 5-fold higher viscosity.

Salivary fluoride concentrations following applications of bioadhesive tablets and mouthrinses.

Presence of elevated fluoride concentration in saliva is important for the prevention of caries. In the present study, we developed an intra-oral bioadhesive tablet aimed at delivering F(-) in the mouth over a prolonged period of time. Various tablet formulations were tested in vivo for their tolerance and adhesiveness. Two formulations were selected for further studies on salivary fluoride clearance. For comparison, mouthrinses with increasing F(-) concentrations were also examined. Results indicate that a bioadhesive tablet located on the upper gingiva is able to sustain salivary F(-) concentrations for about 10h without major side effects. Mouthrinses with high F(-) concentration were able to prolong salivary fluoride retention for more than 6h.

Clinical and microbiological characteristics of smokers with early onset periodontitis.

Cigarette smoking is a potential risk factor which has recently been associated with periodontal disease progression. The objective of this study was to compare the microbial profile of smokers and non-smokers in a group of patients with early onset periodontitis. The study population consisted of 60 healthy individuals, 40 males and 20 females aged 22 to 35 yr, exhibiting early onset periodontitis. Thirty patients were smokers (30.9 cigarettes/d) and 30 non-smokers. Smokers had a higher proportion of deep pockets (PD >5 mm), especially in the maxilla anterior and premolar regions (p < 0.001) and presented a significantly greater mean probing depth and attachment loss (p <0.05) in diseased sites and a significantly greater alveolar bone loss (p <0.01) compared to non-smokers. Two pooled bacterial samples were obtained from each patient. Samples were collected from the deepest periodontal pockets of each quadrant. The samples were cultured anaerobically and in 10% CO2 plus air for bacterial isolation using selective and non-selective media. Isolates were characterized to species level by conventional biochemical tests and various identification kits. Smokers harboured a greater number of bacteria in total. Analysis of bacterial counts using the ANOVA (Mann-Whitney U-test) showed that Staphylococcus aureus, Peptostreptococcus micros, Campylobacter concisus, Escherichia coli, Bacteroides forsythus, C. gracilis, C. rectus, Porphyromonas gingivalis, Selenomonas sputigena, Candida albicans and Aspergillus fumigatus were found in significantly higher numbers and more frequently in smokers while Streptococcus intermedius, A. naeslundii, A. israelii and Eubacterium lentum were detected more frequently and in significantly higher proportions in non-smokers. The isolation of bacteria belonging to the exogenous flora such as E. coli, C. albicans, A. fumigatus and S. aureus in smokers' microbiota underscores the importance of the host that is adversely affected by cigarette smoking.

Scanning electron microscopic study of the effects of Er:YAG laser on root cementum.

Use of Er:YAG laser has been proposed for the removal of microbial deposits and calculus present on teeth affected by periodontal disease. However, the influence of Er:YAG laser irradiation on root surfaces has not yet been fully investigated. The aim of the present study was to evaluate the effects of Er:YAG laser irradiation on root cementum by scanning electron microscopy (SEM). Specimens were obtained from extracted human periodontally-diseased teeth using a water-cooled high-speed bur. An Er:YAG laser beam was then applied at various powers ranging from 25 to 100 mJ/ pulse/sec. The laser irradiation was performed under water irrigation, with the tip held perpendicular to the root surface in the contact mode. Following laser exposure, specimens were fixed, dehydrated, and dried at critical-point in liquid CO2. After mounting on SEM plates and sputter-coating with gold, the cementum surface was examined by SEM. Observations of the root surface showed a relatively flat surface in control specimens. In Er:YAG exposed specimens, the laser beam created a circular, notched-edge, crater-like defect on the root. The bottom of the lesion showed an irregular and sharp-pointed surface. Subsequently, the specimens were fractured with a sharp scalpel perpendicularly to the surface. SEM observations of these specimens showed a 15 microm layer of damaged tissue within the laser-irradiated cementum. The tissue presented an amorphous appearance and the Sharpey's and matrix fiber bundles were not clearly distinguishable. These observations indicate that cementum tissue could be damaged by Er:YAG laser irradiation.

Current status in oral fluoride pharmacokinetics and implications for the prophylaxis against dental caries.

Fluoride plays a central role in the prevention of dental caries. There is evidence that its effect is mainly topical and that continuous presence of fluoride ions in low concentration at the plaque/enamel interface is essential. The present paper reviews the most important aspects of fluoride kinetics in the oral cavity and discusses their implications on preventive approaches to dental caries. As a continuous presence of fluoride ions in saliva is important for an optimum prophylactic effect, new formulations capable of delivering low levels of fluoride over prolonged periods of time have been developed. These systems consist either of intra-oral devices, or of restorative materials into which fluoride has been incorporated. Among all the preparations investigated, bioadhesive tablets and membrane-controlled reservoirs are the most promising.

Effects of an oral health program on selected clinical parameters and salivary bacteria in a long-term care facility.

The aim of this study was to evaluate clinically and microbiologically the effects of a preventive oral health program in a long-term care facility. A total of 116 dentate elderly residents agreed to participate, and half of them were included in an experimental group. Almost all of the residents were mentally or physically handicapped, and many were dependent on care-givers for daily living activities. Oral examination and microbiological sampling were performed at baseline and 18 months later. The experimental group benefited from a preventive program, including an oral hygiene course for the health care providers and regular recalls by dental hygienists of the residents. After 18 months, the plaque indices were statistically similar to those at baseline in both groups. Mutans streptococci counts and active root caries at 18 months were lower compared to baseline in the experimental group but did not change significantly in the control group. Thus, it seems that, while the preventive program failed to decrease plaque indices, it was effective in reducing mutans streptococci colonisation and caries prevalence.

Serum immunoglobulin G responses to various Actinobacillus actinomycetemcomitans serotypes in a young ethnographically heterogeneous periodontitis patient group.

Sera from young patients with periodontal diseases have been shown to often contain highly elevated antibody levels to Actinobacillus actinomycetemcomitans, in particular serotype b. Such responses were reportedly predominated by antibodies of the immunoglobulin G2 (IgG2) subclass. The aim of this study was to investigate an ethnically diverse group of 14 early-onset periodontitis and 15 rapidly progressive periodontitis patients for the occurrence of elevated antibody titers against the five known A. actinomycetemcomitans serotypes, and to compare the patient's IgG subclass response profiles. Enzyme-linked immunosorbent assays were used to measure both total IgG and subclass specific IgG titers. Twenty-four subjects had markedly elevate total IgG levels against at least one serotype. The frequencies of high responses against serotypes a, b, c, d and e were 7, 11, 6, 4, and 4, respectively. Elevated antibody responses were predominated by IgG2, regardless of the serotype to which the response was directed. The serotype specificity of the host responses was further investigated by competitive binding studies with serotype-specific monoclonal antibodies. Twelve sera were found to contain antibodies capable of strongly inhibit the binding of monoclonal antibodies against a single serotype; four other sera had antibodies against epitopes of two, and one serum against those of three serotypes. The findings document broad serotype diversity in an ethnically heterogeneous group of patients and indicate that strong antibody responses to A. actinomycetemcomitans are predominated by IgG2 regardless of the serotype of the infective agent.

Supportive care of the periodontal patient.

The ultimate goal of supportive periodontal care is to maintain health of the dental and oral soft tissues. It represents a preventive measure for individuals who have never experienced periodontal problems. On the other hand, supportive care is a continuation of therapy for the treated periodontal patient, once health has been reestablished. It aims at optimizing the results of therapy and prevent further destruction following active treatment. Attempts are being made to individualize and tailor supportive periodontal care according to the patient's profile and needs. Recent trends also show increased use of antimicrobials as adjuncts to mechanical procedures for controlling the etiologic agents.

Evidence for genetic control of changes in f-actin polymerization caused by pathogenic microorganisms: in vitro assessment using gingival fibroblasts from human twins.

Attachment to and migration upon a substratum, as well as other functions of connective tissue cells, are regulated mainly by cytoplasmic structural proteins, particularly filamentous actin (f-actin). Pathogenic microorganisms exert negative effects on cytoskeletal proteins. In the present study, normal gingival fibroblasts from 10 sets of human twins (6 fraternal, DZ; 4 identical, MZ) were exposed to soluble extracts from Porphyromonas gingivalis or Fusobacterium nucleatum, then f-actin was stained using FITC-labeled phalloidin. Cells were examined under fluorescence, and a computer-assisted image analyzer quantitated f-actin polymerization as fluorescence intensity on a per-cell basis. Intraclass correlation coefficients for f-actin in MZ/MZ vis-a-vis DZ/DZ paired cell cultures were determined to assess the possible heritability of responses to the microorganism preparations. F-actin labeling was significantly different between control cultures and those exposed to the extracts. Both F. nucleatum and P. gingivalis effected f-actin and fibroblast morphology. When the data were adjusted for gender and age effects, and for differences in control f-actin levels, fibroblasts from MZ twin pairs were moderately similar in both absolute and relative responses to bacterial challenges; cells from DZ twins showed little similarity when response was measured on the absolute scale, and moderate similarity using the relative scale.

Oral candidosis in long-term hospital care: comparison of edentulous and dentate subjects.

OBJECTIVE: To obtain information on the oral health status of the elderly living in a medicalized, geriatric institution. DESIGN: A cross-sectional clinical investigation with complementary microbiological studies. SUBJECTS AND METHODS: A cohort of 233 elderly in one long-term care ward; collection of demographic data; clinical examination to determine dental and prosthetic status and health of the oral mucosae; swabs for detection of mucosal and denture colonization by Candida; paraffin stimulated saliva for detection of colonization by mutans streptococci and lactobacilli. MAIN OUTCOME MEASURES: Oral and denture hygiene; oral mucosal health; degree of colonization by Candida, mutans streptococci and lactobacilli. RESULTS: Mean age of the 233 patients was 85.6 +/- 6.9 years; 61% were totally dependent, 62.7% were wearing one or two complete dentures; 19.7% had natural teeth and no denture and 17.6% neither teeth nor denture. Of those wearing dentures 72% had denture stomatitis. Of those with natural teeth 72% were affected by active caries. Yeast counts were significantly correlated with the intensity of the erythema of the palatal mucosa, plaque score of the natural teeth, denture plaque score, and salivary counts of mutans streptococci and lactobacilli. CONCLUSIONS: High oral yeast counts and frequent prevalence of oral candidosis in elderly subjects living in institutions are associated with poor oral hygiene and neglect of denture care.

Caries prevalence and associated predisposing conditions in recently hospitalized elderly persons.

The prevalence of caries and caries risk factors was studied among 120 consecutively hospitalized elderly persons. Coronal caries was recorded using the WHO criteria, and active and inactive root caries in accordance with Fejerskov et al. The CPITN was used to evaluate the periodontal state and plaque accumulation in accordance with Löe & Silness. Of the 1212 teeth examined 5% had active coronal caries (2% inactive), 14% active root caries (2% inactive), and 10% fillings with recurrent caries. No relationship was found between caries prevalence, degree of dependence, number of medicaments, age, and gender. Patients with psychiatric diseases had increased caries prevalence (P < 0.01), and lower caries prevalence was associated with frequent tooth brushing (P < 0.05). At the tooth level root caries was associated with high plaque scores (P < 0.001), degree of gingival recession (P < 0.001), presence of coronal caries (P < 0.001), and increased pocket depth (P < 0.01). The results strongly indicate that oral hygiene measures should be introduced immediately after hospitalization of these patients.