Local inflammatory markers and systemic endotoxin in aggressive periodontitis.

While much research has focused on local and systemic factors contributing to periodontal disease, little is known regarding mechanisms linking these factors. We have previously reported a systemic hyper-inflammatory response to bacterial endotoxin in localized aggressive periodontitis (LAP). The objectives of this study were to delineate cyto/chemokines in gingival crevicular fluid (GCF) and evaluate systemic levels of endotoxin associated with LAP. Clinical parameters, GCF, and peripheral blood were collected from: 34 LAP, 10 healthy siblings, and nine healthy unrelated control individuals. Cyto/chemokines were quantified in GCF, systemic endotoxin levels were quantified in plasma, and correlation analysis was performed among all parameters. Nine mediators were elevated in LAP diseased sites as compared with healthy sites (TNFα, INFγ, IL1ß, IL2, IL6, IL10, Il12p40, GMCSF, and MIP1α, p < 0.001), while MCP1, IL4, and IL8 were elevated in healthy sites (p < 0.01). Four- to five-fold-higher endotoxin levels were detected in LAP plasma compared with that from healthy participants (p < 0.0001), which correlated with all clinical parameters and most cyto/chemokines analyzed. In conclusion, higher systemic levels of endotoxin were found in LAP, which correlates with an exacerbated local inflammatory response and clinical signs of disease. (Clinicaltrials.gov number, NCT01330719).

Could alkali production be considered an approach for caries control?

This study investigated the relationship of arginine deiminase (ADS) and urease activities with dental caries through a case-control study. ADS and urease activities were measured in dental smooth-surface supragingival plaque and whole saliva samples from 93 subjects, who were in three different groups: caries-free (n = 31), caries-active (n = 30), and caries-experienced (n = 32). ADS activity was measured by quantification of the ammonia generated from the incubation of plaque and saliva samples in a mixture containing 50 mM arginine-HCl and 50 mM Tris-maleate buffer, pH 6.0. ADS-specific activity was defined as nanomoles of ammonia generated per minute per milligram of protein. Urease activity was determined by quantification of ammonia produced from 50 mM urea. For bacterial identification and enumeration real-time qPCR analysis was used. Groups were compared using Kruskal-Wallis tests. Spearman correlations were used to analyze plaque metabolic activity and bacterial relationships. The results revealed significantly higher ammonia production from arginine in saliva (1.06 vs. 0.18; p < 0.0001) and plaque samples (1.74 vs. 0.58; p < 0.0001) from caries-free subjects compared to caries-active subjects. Urease levels were about 3-fold higher in the plaque of caries-free subjects (p < 0.0001). Although higher urease activity in saliva of caries-experienced and caries-free subjects was evident, no significant difference was found between the groups.

Preliminary assessment of safety and effectiveness in humans of ProBiora3, a probiotic mouthwash.

AIMS: To conduct a pilot human clinical trial to assess the safety and to test the ability of a probiotic mouthwash, ProBiora(3), to affect the levels of Streptococcus mutans and certain known periodontal pathogens in the mouth when administered twice daily over a period of 4 weeks. METHODS AND RESULTS: The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 10(6) and 10(8) colony forming units each of Strep. oralis strain KJ3sm, Strep. uberis strain KJ2sm, and the spontaneous lactic acid-deficient variant of Strep. rattus, strain JH145. Substantial decreases in the levels of the marker bacteria were observed. No safety issues were noted with the twice daily application of this mouthwash. CONCLUSIONS: Despite the small number of subjects and the use of young, orally healthy adults, along with the inherent variability in the microbiological measurements, the probiotic mouthwash was able to substantially affect the levels of dental pathogens in saliva and periodontal pathogens in subgingival plaque. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this pilot human study suggest that the probiotic mouthwash product may be safe for daily use as an aid in maintaining both dental and periodontal health.

The relationship between dental caries status and dental plaque urease activity.

INTRODUCTION: Ammonia production from the metabolism of urea by urease enzymes of oral bacteria moderates plaque acidification and may inhibit dental caries, as suggested by in vitro studies and indirect clinical observations. The objective of this study was to examine the relationship of urease activity with dental caries at the clinical level. METHODS: Urease activity was measured in dental plaque and saliva samples from 25 caries-free subjects (CF) and in eight subjects with six or more open caries lesions (CA). Plaque and saliva collection was repeated for each subject 1 week later using identical procedures. RESULTS: Urease-specific activity in the dental plaque of CF subjects was significantly higher compared to that in the subjects with caries. The association of low plaque urease levels with increased caries was further supported by odds ratio analysis using different plaque urease cut-off points. Using a receiver operating characteristic curve it was estimated that there was an approximately 85% probability of correctly classifying the subjects as CA or CF based on the relative ordering of their plaque urease activity levels. No statistically significant differences were observed in salivary urease activity. CONCLUSION: This study suggests that loss of alkali-generating potential of tooth biofilms via the urease pathway has a positive relationship to dental caries.

Accuracy of probing attachment levels using a CEJ probe versus traditional probes.

BACKGROUND: Current interest in the assessment of probing attachment level measurements has been stimulated by recent introduction of novel periodontal probes as well as by the reclassification of periodontal diseases. Clinical attachment level (CAL) is currently the "gold standard" for diagnosing and monitoring periodontal diseases. AIM: To evaluate the performance of the newly introduced cementoenamel junction (CEJ) Probe in detecting CAL using the CEJ as a fixed reference point, and to compare the CEJ Probe with the Florida Disk Probe and a standard Manual Probe (North Carolina Probe). MATERIALS AND METHODS: Three examiners probed 12 periodontal patients to determine intra- and inter-consistency of both the probes and the examiners, over a 4-week time interval. Subjects ranged in age from 22 to 74 years. The experimental design was structured to balance the intra- and inter-examiner consistency at the same site during the two visits. RESULTS: Using the PROC MIXED of SAS, a strong interaction (p<0.001) between the examiner and probes was found. The consistency of probing (repeatability of measurements) depended upon the type of periodontal probe used as well as the skill (experience) of the examiner. Overall, the CEJ Probe displayed a more consistent performance. The CEJ Probe demonstrated greater intra-examiner consistency than the Disk Probe for two examiners (p<0.01). The CEJ Probe also showed increased inter-examiner consistency (p<0.01). CONCLUSIONS: The CEJ Probe has the potential to offer the dental team an efficient, accurate mechanism to chart and monitor attachment level measurements over time. Additional studies, using large numbers of examiners, are needed to assess more clearly the performance of each individual probe.

Allopurinol as prophylaxis against pouchitis following ileal pouch-anal anastomosis for ulcerative colitis. A randomized placebo-controlled double-blind study.

BACKGROUND: Pouchitis is the major long-term complication of restorative proctocolectomy for ulcerative colitis (UC). Allopurinol is a scavenger of oxygen-derived free radicals, which it is suggested play a role in the development of UC and pouchitis. The first aim was to test the hypothesis that the incidence of pouchitis can be reduced by prophylactic Allopurinol, and secondly to evaluate if Allopurinol influences the overall pouch function. METHODS: 273 patients with UC who were planned for proctocolectomy and ileal pouch-anal anastomosis at 12 centres in Sweden between October 1994 and June 1997 were offered the opportunity to participate. 184 patients (67%) were randomized to receive postoperative prophylactic Allopurinol 100 mg twice daily or placebo. All 273 patients had clinical and endoscopic follow-up at 1, 3, 6, 12, 18, 24 months after surgery. RESULTS: Of the 184 randomized patients, 94 were randomized to Allopurinol and 90 to placebo; 116 patients (63%) completed follow-up and the crude incidence of pouchitis among those patients fullfilling the protocol was 31% in the Allopurinol group and 28% in the placebo group (ns). The cumulative risk for a first attack of pouchitis was 30% and 26% after 24 months (ns). The overall pouch function improved over time and did not differ significantly between the two groups. CONCLUSIONS: Prophylactic Allopurinol did not reduce the risk of a first attack of pouchitis.

Intrapocket anesthesia for scaling and root planing: results of a double-blind multicenter trial using lidocaine prilocaine dental gel.

BACKGROUND: The efficacy of a novel anesthetic gel (lidocaine 25 mg/g plus prilocaine 25 mg/g in thermosetting agents) for non-invasive periodontal pocket anesthesia was evaluated. METHODS: One hundred twenty-two (122) patients in 8 centers with moderate to severe periodontitis requiring scaling and root planing (SRP) were enrolled in this multicenter, randomized, double-blind, controlled clinical trial. The active dental gel or a matching placebo gel was applied into the periodontal pocket using a blunt applicator. Following a waiting period of 30 seconds to 2 minutes, scaling and root planing were performed. If the patient had any discomfort, a second application of the gel was applied. If the patient continued to experience discomfort, conventional anesthesia was offered. After all teeth in the test quadrant had received SRP, the overall pain was assessed by the patient using a 100 mm horizontal, ungraded visual analog scale in which the left side was marked "no pain" and the right side marked "worst pain imaginable." Patients also assessed pain by using a 5-point verbal rating scale, from "no pain" to "very severe pain." RESULTS: The visual analog scale showed significant reductions in reported pain, favoring the active gel over the placebo (mean reduction, 8 mm; P <0.0005). The verbal rating scale revealed that 90% of patients treated with active gel reported no pain or mild pain compared to 64% of placebo-treated patients (P<0.001). CONCLUSIONS: Intrapocket administration of lidocaine 25 mg/g plus prilocaine 25 mg/g and thermosetting agents may be effective for pain control for scaling and root planing and may offer an alternative to infiltration anesthesia.

Contribution of net hepatic glycogen synthesis to disposal of an oral glucose load in humans.

The contribution of hepatic glycogen synthesis to whole body glucose disposal after an oral glucose load was examined using (13)C nuclear magnetic resonance (NMR) spectroscopy to measure liver glycogen content in healthy, volunteers after an overnight fast. In group 1 (n = 14), hepatic glycogen synthesis was measured using (13)C-NMR spectroscopy for 240 minutes after ingestion of 98 +/- 1 g glucose. Liver volumes were measured using magnetic resonance imaging (MRI). To assess the direct (glucose --> glucose-6-P --> glucose-1-P --> uridine diphosphate (UDP)-glucose --> glycogen) and indirect (3-carbon units --> --> glycogen) pathways of liver glycogen synthesis, group 2 (n = 6) was studied with an identical glucose load enriched with [1-(13)C]glucose along with acetaminophen to noninvasively assess the (13)C enrichment in hepatic UDP-glucose. The fasting hepatic glycogen content was 305 +/- 17 mmol/L liver, and the liver volume was 1.46 +/- 0.07 L. For the initial 180 minutes after ingestion of glucose, hepatic glycogen concentrations increased linearly (r =.94, P =.0006) achieving a maximum concentration of 390 +/- 7 mmol/L liver and then remained constant until the end of the study. The mean maximum rate of net hepatic glycogen synthesis was 0.48 +/- 0.07 mmol/L liver-minute. Total liver glycogen synthesis could account for 16.7 +/- 3.8 g (17% +/- 4%) of the glucose ingested, and of this, 10.5 +/- 2.4 g (63% +/- 7%) was synthesized by the direct pathway. In conclusion, after ingestion of 98 g of glucose: (1) 16.7 +/- 3.8 g (17% +/- 4%) glucose was stored in the liver as glycogen, and (2) 63% +/- 7% (10.5 +/- 2.4 g) of this glycogen was formed via the direct pathway.

Treatment of periodontitis by local administration of minocycline microspheres: a controlled trial.

BACKGROUND: Periodontitis is an inflammatory condition of tooth-supporting tissues that is usually treated by mechanical removal of plaque and microorganisms that adhere to teeth. This treatment, known as scaling and root planing, is not optimally effective. Adjunctive therapy with locally delivered antimicrobials has resulted in improved clinical outcomes such as probing depth reduction. This article reports on the efficacy and safety of locally administered microencapsulated minocycline. METHODS: Seven hundred forty-eight (748) patients with moderate to advanced periodontitis were enrolled in a multi-center trial and randomized to 1 of 3 treatment arms: 1) scaling and root planing (SRP) alone; 2) SRP plus vehicle; or 3) SRP plus minocycline microspheres. The primary outcome measure was probing depth reduction at 9 months. Clinical assessments were performed at baseline and 1, 3, 6, and 9 months. RESULTS: Minocycline microspheres plus scaling and root planing provided substantially more probing depth reduction than either SRP alone or SRP plus vehicle. The difference reached statistical significance after the first month and was maintained throughout the trial. The improved outcome was observed to be independent of patients' smoking status, age, gender, or baseline disease level. There was no difference in the incidence of adverse effects among treatment groups. CONCLUSIONS: Scaling and root planing plus minocycline microspheres is more effective than scaling and root planing alone in reducing probing depths in periodontitis patients.

Thymidylate synthase expression: an independent prognostic factor for local recurrence, distant metastasis, disease-free and overall survival in rectal cancer.

Several studies have suggested that the intratumoral level of thymidylate synthase (TS) in colorectal tumors correlates with survival. We have studied the correlation between TS expression in primary rectal cancer and locoregional recurrence, distant metastases, and survival. TS enzyme levels were evaluated immunohistochemically using the specific monoclonal antibody TS 106 in paraffin-embedded tumors from 243 patients who had undergone primary surgery for rectal cancer during the years 1980-1993. All patients were included in prospective randomized trials aimed at determining the clinical value of a short preoperative course of local radiation therapy (five doses of 5 Gy each). With a median follow-up of 94 months (range, 43-202 months), it was observed by multivariate analysis that Dukes' stage and TS expression were independent prognostic markers of locoregional recurrence (P < 0.001 and P = 0.038, respectively) distant metastasis (P < 0.001 and P = 0.011, respectively) disease-free survival (P < 0.001 and 0.014, respectively), and overall survival (P < 0.001 and 0.020, respectively). By multivariate analysis, preoperative irradiation therapy showed a borderline improvement in locoregional recurrence (P = 0.051). No other factors, such as age, sex, differentiation of the tumor, or p53 expression, were noted to be independent prognostic factors for clinical outcome in these patients. We concluded that the intratumoral expression of TS in primary rectal cancer is an independent prognostic factor for locoregional recurrence, distant metastases, disease-free survival, and overall survival. Patients with low intratumoral TS expression had a significantly better outcome than those with high TS expression.

Immunohistochemically detected thymidylate synthase in colorectal cancer: an independent prognostic factor of survival.

Intratumoral thymidylate synthase (TS) expression and M(r) 53,000 phosphoprotein (p53) overexpression were studied immunohistochemically in sections from stored paraffin-embedded primary colorectal cancers in 70 patients who had undergone surgery during the years 1987-1990. These cancers were classified according to Dukes' stage A-D, using monoclonal antibodies TS 106 and DO-7. In patients with Dukes' stage A-C tumors, univariate analyses showed that there was a significant correlation (P = 0.048) between disease-free survival and TS expression and between TS expression and time to death with colorectal cancer (P = 0.038). In patients with Dukes' stage A-D tumors, overall survival was correlated to TS expression (P = 0.015), Dukes' stage (P < 0.001), and level of tumor differentiation (P = 0.044) but not to p53 overexpression. Patients with low intratumoral TS expression survived significantly longer than patients with high expression. Cox multivariate analysis showed that Dukes' stage (P < 0.001) and TS expression (P = 0.043) could independently serve as prognostic factors for time to death with colorectal cancer in patients with Dukes' stage A-D tumors.

Recent approaches to periodontal therapy.

Periodontal diseases encompass a variety of disease classifications, all involving inflammation of the supporting tissues of the teeth. When progressive, these diseases ultimately lead to the destruction of attachment apparatus including bone and periodontal ligament, culminating in eventual tooth loss. Inflammation extends from superficial gingival structures, effecting adjacent submerged bone and periodontal ligament. Progression modifies an initially highly favourable, reversible diagnosis of gingivitis to a less favourable, somewhat irreversible situation: periodontitis. Periodontal diseases manifest variable and sometimes unpredictable prognoses, are generally somewhat complicated and costly to treat and often require long-term follow-up for maintenance and monitoring. Treatment aims at restoration of health and control of future disease within a functional, albeit reduced, periodontium. In the strictest sense, periodontal diseases are not 'cured'. The conventional, usually successful, approach to the treatment of patients with gingivitis or chronic periodontitis has involved non-surgical mechanical periodontal therapy [1,2]. Some patients manifest localised or generalised continuous attachment loss and periodontal destruction. These sites are prime candidates for alternative therapeutic regimens. This review highlights some of the recent advances in periodontal therapy and evokes some questions that should be addressed during future studies.

The use of locally delivered metronidazole in the treatment of periodontitis. Clinical results.

Local delivery of antimicrobials has been investigated as a possible method for controlling and treating periodontal disease. A number of antimicrobial agents have been studied both as adjunctive therapies with scaling and root planing and as stand-alone chemotherapies. More recent investigations have focussed on the delivery of antimicrobials in sustained-release formulations designed to maintain effective concentrations of drug within the periodontal pocket. This article provides an overview of the development of the use of locally-delivered metronidazole in periodontal therapy and the current state-of-the-art of the technique. It is concluded that treatment with local delivery of metronidazole seems to be as effective as scaling and root planing in untreated as well as in recall subjects. However, there are reasons to suggest that local delivery of metronidazole should not be used as a substitute for conventional treatment of periodontal disease, since side-effects of long-term use and repeated use are not known. The antibiotic regimen should preferably be used as an adjunct to surgical and non-surgical therapy.

Option-3 median measurement scheme in outlier reduction.

When measurement are subject to rare but large errors, it is better to measure twice instead of once, and, if the two measurements differ too much, to take a third measurement. This is called the option-3 scheme. This paper shows that when the measurement error is the mixture of two normal random variables, use of the median of the three measurements is better than use of the average of the two closest. To reach the maximum sample size benefit, the threshold for taking the third measurement is approximately three times the measurement error standard deviation.

Local delivery of antimicrobial agents for the treatment of periodontitis.

Periodontitis is a result of an infection with specific pathogenic microorganisms. Thus, the local delivery of antimicrobials has been investigated as a possible method for controlling this infection and treating periodontal disease. A number of antimicrobial agents have been studied both as adjunctive therapies with scaling and root planing and as stand-alone chemotherapies. These agents have been administered in irrigation solutions and as single-dose formulations, but with little long-term efficacy in the treatment of periodontitis. Recent investigations have focused on the delivery of antimicrobials in sustained-release formulations designed to maintain effective concentrations of drug within the periodontal pocket. This article provides an overview of the development of the use of locally delivered antimicrobials in periodontal therapy and the current state-of-the-art of the technique.

Mechanism of impaired insulin-stimulated muscle glucose metabolism in subjects with insulin-dependent diabetes mellitus.

To determine the mechanism of impaired insulin-stimulated muscle glycogen metabolism in patients with poorly controlled insulin-dependent diabetes mellitus (IDDM), we used 13C-NMR spectroscopy to monitor the peak intensity of the C1 resonance of the glucosyl units in muscle glycogen during a 6-h hyperglycemic-hyperinsulinemic clamp using [1-(13)C]glucose-enriched infusate followed by nonenriched glucose. Under similar steady state (t = 3-6 h) plasma glucose (approximately 9.0 mM) and insulin concentrations (approximately 400 pM), nonoxidative glucose metabolism was significantly less in the IDDM subjects compared with age-weight-matched control subjects (37+/-6 vs. 73+/-11 micromol/kg of body wt per minute, P < 0.05), which could be attributed to an approximately 45% reduction in the net rate of muscle glycogen synthesis in the IDDM subjects compared with the control subjects (108+/-16 vs. 195+/-6 micromol/liter of muscle per minute, P < 0.001). Muscle glycogen turnover in the IDDM subjects was significantly less than that of the controls (16+/-4 vs. 33+/-5%, P < 0.05), indicating that a marked reduction in flux through glycogen synthase was responsible for the reduced rate of net glycogen synthesis in the IDDM subjects. 31P-NMR spectroscopy was used to determine the intramuscular concentration of glucose-6-phosphate (G-6-P) under the same hyperglycemic-hyperinsulinemic conditions. Basal G-6-P concentration was similar between the two groups (approximately 0.10 mmol/kg of muscle) but the increment in G-6-P concentration in response to the glucose-insulin infusion was approximately 50% less in the IDDM subjects compared with the control subjects (0.07+/-0.02 vs. 0.13+/-0.02 mmol/kg of muscle, P < 0.05). When nonoxidative glucose metabolic rates in the control subjects were matched to the IDDM subjects, the increment in the G-6-P concentration (0.06+/-0.02 mmol/kg of muscle) was no different than that in the IDDM subjects. Together, these data indicate that defective glucose transport/phosphorylation is the major factor responsible for the lower rate of muscle glycogen synthesis in the poorly controlled insulin-dependent diabetic subjects.

Evaluating the merits of option-3 methods in relative attachment level measurement in a healthy population.

Attachment loss is the principal clinical indicator for periodontal disease progression. However, the attachment measurement can be inaccurate due to outliers. A remedial scheme, the option-3 scheme, has been suggested in the literature. This scheme involves first measuring the relative attachment twice at any given site. A third measurement is required if there is a large disagreement between the first two probings. When the third measurement is taken, there are several possible ways to make the final assessment of the true attachment level. Among them are the average of the 3 measurements, the average of the closest 2, and the median of the 3. This report evaluates the merits of the option-3 scheme by comparing it with other schemes to reduce measurements variance and outliers. Since true attachment levels are unknown, we chose to check accuracy through measurement consistency between visits in healthy subjects using the fact that such subjects should have little real change in attachment levels. 12 healthy subjects participated in the study. They visited the clinic 4 times in 4 months. Two types of the Florida stent probe were used by 2 calibrated examiners. It was found that option-3 schemes were more accurate than a single probing or duplicate probings in estimating the relative attachment level. The 3 final assessment schemes performed almost equally well from a practical standpoint, but the median was the best among them in a statistical sense.

Immunohistochemical determination of thymidylate synthase in colorectal cancer--methodological studies.

With the aid of specific monoclonal antibodies, an immunohistochemical technique has recently been developed for the detection of intratumoral thymidylate synthase (TS). This technique can be applied to paraffin-embedded material suitable for retrospective studies. In order to examine this technique further, the TS enzyme activity of lysates from frozen-stored colorectal cancer (CRC) specimens were compared with their immunohistochemical TS staining intensity (arbitrarily graded from 0 to 3). A statistically significant correlation between these two methods on a total of 25 tumour specimens (P < 0.001) was observed. The staining intensity in different areas of 48 paraffin-embedded CRCs was examined. Sixty-seven per cent of the tumours were homogeneously stained (either grades 0-1 or 2-3), 33% showed a heterogeneity in TS staining. Increased TS expression correlated with more advanced Dukes' stage (P < 0.001). It is concluded that TS immunostaining intensity reflects TS enzyme activity in colorectal tumours and is well suited for paraffin-embedded material. The TS immunostaining pattern is heterogeneous in up to one-third of the tumours.

Oral diseases, mycology and periodontal microbiology of HIV-1-infected women.

HIV-1 infection is increasing more rapidly among heterosexual women. Relatively limited information is available on HIV-related oral pathoses in these individuals. To gain insight into the type and occurrence of oral lesions in this population, 25 HIV-1 infected women including asymptomatic, symptomatic and AIDS patients were examined clinically and sampled for detection of oral yeast and characterization of their subgingival microbial flora. Sixty percent of the subjects were African-American, with 80% infected via heterosexual contact. Oral candidiasis was the most common nonperiodontal oral lesion, observed in 44% of the patients. Oral yeast was cultured from all women with candidiasis and 76% of the total subjects. Oral hairy leukoplakia was clinically diagnosed in 16% of the subjects. Clinically mild to moderate gingivitis and periodontitis were observed in 84% and 52% of the patients, respectively. Candidiasis and the presence of cultivable yeast were observed in patients with low, intermediate, and high CD4+ T lymphocyte numbers. Plaque samples were collected from each subject and enumerated by predominant cultivable methods, selective media and microscopy. No differences were detected in the microflora associated with seropositive women with existing periodontitis relative to those without periodontitis or to seronegative women with periodontitis. Candidiasis was the most notable oral clinical manifestation in the HIV-1-infected women and may be a useful clinical indicator of early immune dysfunction mediated by HIV-1.