IL-1 in gingival crevicular fluid following closed root planing and papillary flap debridement

Interleukin-1β is a potential therapeutic target for periodontitis: a narrative review

Interleukin(IL)-1β, a pro-inflammatory cytokine, was elevated and participates in periodontitis. Not only the link between IL-1β and periodontitis was proved by clinical evidence, but also the increased IL-1β triggers a series of inflammatory reactions and promotes bone resorption. Currently, IL-1β blockage has been therapeutic strategies for autoimmune and autoinflammatory diseases such as rheumatoid arthritis, cryopyrin-associated periodic syndromes, gout and type II diabetes mellitus. It is speculated that IL-1β be a potential therapeutic target for periodontitis. The review focuses on the production, mechanism, present treatments and future potential strategies for IL-1β in periodontitis.

A pilot study of the gingival response when smokers switch from smoking to vaping

Introduction Tobacco smoking is one of the most important risk factors for periodontitis as it alters the host response to plaque. Although the prevalence of tobacco smoking has declined in recent years, the use of electronic-cigarettes (vaping) has increased. The effect of vaping on the gingiva is unknown and an evidence-base needs to be established before providing dental advice about the use of these products.Objective To compare the gingival health of a group of established smokers before and after substituting vaping for smoking tobacco.Design Pilot.Setting Guy's Dental Hospital (England) from April-December 2015.Materials and methods Twenty established smokers (all staff members at Guy's Hospital) with mild periodontal disease replaced their regular smoking habits with the use of e-cigarettes for two weeks.Main outcome measure The primary outcome measure of gingival inflammation was bleeding on probing. Levels of selected pro-inflammatory cytokines in GCF, saliva and serum samples were also determined.Results and conclusions There was a statistically significant increase in gingival inflammation when tobacco smokers switched from smoking to vaping for two weeks. However, this result must be interpreted with extreme caution since this is only a pilot study. Nonetheless, this study should provide a stepping stone to encourage further investigation of the effects of vaping on periodontal health.

Effects of initial periodontal therapy on interleukin-1β level in gingival crevicular fluid and clinical periodontal parameters

Inflammatory cytokines may have important roles in periodontitis. We assessed the effects of initial periodontal therapy on clinical periodontal parameters and interleukin-1β (IL-1β) level in gingival crevicular fluid (GCF) from chronic periodontitis (CP) patients. After initial screening, baseline periodontal parameters such as probing pocket depth (PPD) and bleeding on probing (BOP) were measured. GCF samples were collected from 13 shallow (≤3 mm) and deep (≥5 mm) PPD sites from 13 CP patients, and GCF volume and IL-1β concentration were determined at baseline (before scaling and root planning) and at 2 and 4 months after initial therapy. Baseline BOP rate, GCF volume, and IL-1β level were significantly higher at deep PPD sites than at shallow PPD sites. Significant improvements in PPD and BOP were observed at 2 and 4 months after periodontal initial therapy in deep PPD sites only. In contrast, GCF volume and IL-1β concentration were lower at 2 and 4 months after initial therapy at all sites. These results suggest that GCF volume and IL-1β level in samples reflect disease severity and that these variables are better than PPD and BOP as markers of gingival inflammation.

Polymorphisms of Il-10 (-1082) and RANKL (-438) Genes and the Failure of Dental Implants

Background. Genetic polymorphisms in certain cytokines and chemokines have been investigated to understand why some individuals display implant flaws despite having few risk factors at the time of implant. Purpose. To investigate the association of genetic polymorphisms in interleukin- (IL-) 10 [-1082 region (A/G)] and RANKL [-438 region (A/G)] with the failure of dental implants. Materials and Methods. This study included 90 partially edentulous male and female patients who were rehabilitated with a total of 245 Straumann dental implants. An implant was considered a failure if any of the following occurred: mobility, persistent subjective complaint, recurrent peri-implant infection with suppuration, continuous radiolucency around the implant, probing depth ≥ 5 mm, and bleeding on probing. Buccal mucosal cells were collected for analysis of RANKL438 and IL-10. Results. The implant success rate in this population was 34.4%. The mutant allele (G) in RANKL had an incidence of 52.3% and mutant allele (A) in IL-10 was observed in 37.8%. No statistically significant difference was detected between the failure of the implant and the genotypes and allelic frequencies. Conclusion. No association was detected between the genetic polymorphisms of RANKL (-438) and IL-10 (-1082) and the failure of dental implants in the population studied.

Increased early inflammatory response and osteoclastic activity in gingival tissues following conventional osseous resective surgery compared with the fibre retention technique: a pilot study

BACKGROUND AND OBJECTIVE

The retention of suprabony connective fibres attached into the root cementum during fibre retention osseous resective surgery (FibReORS) results in a more conservative intrasurgical removal of bone, and limits further bone loss and patient morbidity during healing, compared with conventional osseous resective surgery (ORS). This may be a result of the protective effect of preserved connective tissue over the interproximal sites and the lower activation of the inflammatory mechanisms. Thus, the aim of this pilot study was to compare the expression of inflammatory and osteoclastic activity markers in gingival tissues following FibReORS and ORS in the early postsurgical phase.

MATERIAL AND METHODS

Twenty-six posterior sextants requiring osseous resective surgery were selected in 13 patients with chronic periodontitis: 13 sextants were randomly assigned to ORS and 13 to FibReORS in a split-mouth design. Gingival biospies were collected during the surgical sessions and at suture removal. Tissue samples were analysed to evaluate the expression of proinflammatory and immunity regulatory mediators (interleukin-1α, C-X-C motif chemokine ligand 5, interferon-γ and tumour necrosis factor-α), cluster of differentiation 14 (CD14; a monocyte/macrophage marker) and TRAP (an osteoclast marker) using immunohistochemical, immunofluorescence and cytofluorimetric analyses, respectively.

RESULTS

Postsurgery, a higher number of inflammatory cells and stronger expression of proinflammatory cytokines were observed in the epithelium and connective tissue of ORS gingival samples compared with FibReORS gingival samples (p < 0.001). This was accompanied by increased numbers of CD14-positive and TRAP-positive cells.

CONCLUSION

Retention of the supracrestal connective fibres appears to reduce the postsurgical intensity of the host-mediated inflammatory response.

Effects of curcumin on crevicular levels of IL-1β and CCL28 in experimental gingivitis

BACKGROUND

Curcumin has anti-inflammatory properties. The aim of this study was to compare interleukin-1β (IL-1β) and chemokine (C-C motif) ligand 28 (CCL28) levels following a topical application of curcumin (CRM), chlorhexidine (CHX) and chlorhexidine-metronidazole (CHX-MTZ) in an experimental gingivitis human model.

METHODS

Sixty systemically healthy selected subjects were randomly assigned to one of three topical antigingivitis gels. Each gel was applied twice daily for 10 minutes as the sole method of oral hygiene for 29 days on the test quadrant only. Modified gingival index (MGI), plaque index (PI), bleeding on probing (BOP) and probing depth (PD) were assessed at baseline, 29 days and 60 days. Estimation of IL-1β and CCL28 levels in gingival crevicular fluid was done at baseline and at 29 days.

RESULTS

The increase of IL-1β in the CRM (14.52 ± 16.6 pg/ml) and CHX-MTZ (31.63 ± 15.96) groups was significantly less than that of the CHX group (70.55 ± 38.81). Similar results were also observed for CCL28 (CRM: 8.12 ± 8.78 pg/ml; CHX-MTZ: 12.81 ± 18.68; CHX: 41.15 ± 22.82). All groups had a significant increase in MGI, PI and BOP at 29 days.

CONCLUSIONS

The anti-inflammatory potential of topical curcumin was similar to CHX-MTZ but superior to CHX in affecting IL-1β and CCL28 levels.

Surgical periodontal therapy with and without initial scaling and root planing in the management of chronic periodontitis: a randomized clinical trial

AIM

To compare the outcomes of surgical periodontal therapy with and without initial scaling and root planing.

METHODS

Twenty-four patients with severe chronic periodontitis were enrolled in this pilot, randomized controlled clinical trial. Patients were equally allocated into two treatment groups: Control group was treated with scaling and root planing, re-evaluation, followed by Modified Widman Flap surgery and test group received similar surgery without scaling and root planing. Clinical attachment level, probing depth and bleeding on probing were recorded. Standardized radiographs were analysed for linear bone change from baseline to 6 months. Wound fluid inflammatory biomarkers were also assessed.

RESULTS

Both groups exhibited statistically significant improvement in clinical attachment level and probing depth at 3 and 6 months compared to baseline. A statistically significant difference in probing depth reduction was found between the two groups at 3 and 6 months in favour of the control group. No statistically significant differences in biomarkers were detected between the groups.

CONCLUSIONS

Combined scaling and root planing and surgery yielded greater probing depth reduction as compared to periodontal surgery without initial scaling and root planing.

Necessity of keratinized tissues for dental implants: a clinical, immunological, and radiographic study

BACKGROUND

Necessity of keratinized tissues (KTs) for maintaining health around dental implants (DIs) remains as a controversial issue.

PURPOSE

The aim of this study was to investigate the effects of KT width (KTW) on peri-implant tissues by evaluating peri-implant clinical and inflammatory parameters.

MATERIALS AND METHODS

Sixty DIs were included in this 6-month longitudinal study. After classifying DI based on the presence of KTs at the buccal aspect as with adequate/inadequate KTW, DIs were randomly assigned into three study groups. In the first group, while free gingival graft (FGG) was performed, DIs in maintenance (M) group were followed up by standardized maintenance procedures at baseline, first, third, and sixth months as with DI with adequate KTW (Control). Clinical parameters, peri-implant sulcular fluid (PISF) volume, PISF Interleukin 1β concentration, and bone loss were analyzed.

RESULTS

Significant improvements in clinical and immunological parameters were noted only for FGG for the whole study period. Statistical differences detected between the treatment groups (FGG vs M) were for gingival index at all time points and for PISF volume at sixth month. For the other parameters evaluated, while lower values were observed for FGG, statistically no differences were noted between the groups.

CONCLUSIONS

Based on the results of this study, it can be suggested that FGG performed around DIs lacking KT is a reliable method, leading to significant improvements in clinical and inflammatory parameters. Further long-term studies including more DIs are needed to clarify the role of KT on maintenance of DIs.

Salivary interleukin-1β levels in patients with chronic periodontitis before and after periodontal phase I therapy and healthy controls: a case-control study

BACKGROUND

The role of interleukin (IL)-1β in periodontal disease pathogenesis is well researched. This study aimed to assess and compare the salivary IL-1β levels in patients with chronic periodontitis before and after periodontal phase I therapy and periodontally healthy controls. Further, relationships between IL-1β levels and various clinical parameters were explored.

METHODS

Twenty-eight patients with moderate-to-severe generalized chronic periodontitis and 24 age-, race-, and ethnicity-matched controls participated in this study. Saliva samples were obtained from all patients. The clinical parameters recorded were clinical attachment loss (AL), probing depth, bleeding on probing, periodontal index, and gingival index. Clinical evaluation and sample collection were repeated 1 month after periodontal phase I therapy in patients with periodontitis. IL-1β levels were assessed using enzyme-linked immunosorbent assay.

RESULTS

Mean IL-1β levels in patients with periodontitis at baseline (1,312.75 pg/mL) were significantly higher (P <0.0001; eight-fold) than in controls (161.51 pg/mL). Although treatment in patients with periodontitis resulted in significant reduction in IL-1β levels (mean: 674.34 pg/mL; P = 0.001), they remained significantly higher (P <0.0001; four-fold) than control levels. There were significant correlations between IL-1β levels and all clinical parameters (P <0.01) except percentage sites with clinical AL >2 mm (P >0.05).

CONCLUSIONS

The data indicate that IL-1β levels are raised in the saliva of patients with chronic periodontitis, which are reduced after phase I therapy, suggesting a close association between salivary IL-1β and periodontitis. Additional longitudinal studies are needed to validate salivary IL-1β as a marker for periodontal disease.

Correlation of levels of interleukin-1β in gingival crevicular fluid to the clinical parameters of chronic periodontitis

AIM

BACKGROUND AND OBJECTIVES

IL-1β is a potent stimulator of bone resorption and has been implicated in the pathogenesis of periodontal destruction. Therefore, this study was designed to compare the levels of IL-1β of chronic periodontitis patients with the healthy subjects. Another objective of this study was to correlate IL-1β levels with the clinical parameters of the periodontal disease progression.

METHODS

For this study, total 60 subjects were chosen (30- healthy and 30-chronic periodontitis). Simplified oral hygiene index (OHI-S), gingival index (GI), periodontal disease index (PDI), probing depth (PD), tooth mobility, bleeding on probing (BOP) were recorded for all the subject. Gingival crevicular fluid (GCF) was collected and subjected for ELISA for estimation of IL-1β.

RESULTS

At the periodontal diseased sites, the IL-1β levels increased at least 2-fold as compared with healthy subjects. This increase was highly significant (p = 0.0000). Within the test group, IL-1β levels correlated positively and significantly with PDI, PD, BOP and tooth mobility. The correlations of IL-1β with PD (p = 0.000) and IL-1β with BOP (p = 0.0004) were highly significant.

INTERPRETATION AND CONCLUSION

These data suggest that amount of GCF IL-1β is closely associated with periodontal status. This relationship may be valuable in monitoring periodontal disease activity.

CLINICAL SIGNIFICANCE

It could be stated from this study on IL- 1β that there seem to be a strong correlation between periodontal tissue destruction and IL-1β. Furthermore IL-1β level could also differentiate between active and inactive periodontal lesions.

The effect of age on the gingival crevicular fluid composition during experimental gingivitis. A pilot study

Background:

Cytokines have been proposed as potentially useful diagnostic or prognostic markers of periodontal inflammation related alterations during the experimental gingivitis model. The role of ageing in periodontal disease needs further elucidation; therefore investigations of its influence on host response are needed.

Objective:

To study the effect of age on interleukins IL -6, IL-8 and TNF-a levels in gingival crevicular fluid (GCF) and their correlations to clinical parameters during experimental gingivitis.

Materials and Methods: Five young subjects (20-22 years old) and five old subjects (61-65 years old), all periodontal healthy, participated in this clinical trial. A professional plaque control programme was undertaken to establish healthy gingival conditions at baseline. Plaque index (PI), gingival index (GI) were recorded at 60 sites at baseline, after 21 days of no oral hygiene and one week later after professional cleaning and reestablishment of oral hygiene procedures. A total of 180 samples were analyzed with ELISA for levels of IL -6, IL-8 and TNF-a in gingival crevicular fluid. The examination included the mesiobuccal sites of the Ramfjord teeth. Comparisons between and within groups were performed by non-parametric tests (Mann- Withney) and correlations were sought for with Wilcoxon test. Significance was set at p=0.05.

Results:

Results showed significant diferences between the two groups with regard to the plaque and bleeding scores and GCF volume, all of which proved to be more pronounced in old group. With respect to laboratory data, mean cytokine concentrations were in general lower in young group. TNF-a had a steady increase for the adults, which was found to be statistically significant between Days 0 and 21, IL-8 showed a statistically significant decrease at Day 28 in the young group and finally IL-6 showed a fluctuation, which was totally adverse for the two groups at each time point.

Conclusion:

Within the limitations of the present study, age cannot be identified as a factor that strongly affects the cytokine expression and fluctuations even in a well-controlled environment of inflammation, such as experimental gingivitis.

Enamel Matrix Derivative and Systemic Antibiotics as Adjuncts to Non-Surgical Periodontal Treatment: Biologic Response

BACKGROUND

Short-term clinical observations suggest an anti-inflammatory effect of enamel matrix derivative (EMD). The purpose of this study was to evaluate the anti-inflammatory capacity of EMD, used as an adjunct to non-surgical periodontal treatment of deep lesions in chronic periodontitis patients, by monitoring inflammatory markers in gingival crevicular fluid (GCF).

METHODS

Sixteen subjects were randomly assigned to treatment with EMD or placebo in contralateral dentition areas. Half of the subjects received 250 mg metronidazole and 375 mg amoxicillin three times a day for 7 days; the other half received a placebo. GCF samples were collected from one interproximal lesion in each of the contralateral quadrants before treatment and after 10 days and 2, 6, and 12 months. Total protein content was determined according to the Bradford method. Myeloid-related protein (MRP) 8/14 and interleukin (IL)-1beta were analyzed quantitatively by enzyme-linked immunosorbent assay (ELISA), and elastase activity was determined using a low molecular weight fluorogenic substrate.

RESULTS

No significant differences were observed between sites treated with or without EMD for any biochemical parameter. Two months after treatment, subjects treated with antibiotics exhibited less clinical signs of inflammation. Furthermore, these subjects had lower MRP 8/14 levels only at day 10 compared to those receiving the placebo. For total protein, IL-1beta, and elastase, no statistically significant differences were noted for subjects with or without antibiotic therapy at any time point.

CONCLUSIONS

Improved healing of the soft tissues has been noted clinically in non-surgically treated sites in subjects treated with antibiotics. The expression of inflammatory mediators in GCF corroborated this finding only in part. EMD did not seem to further affect the expression of inflammatory mediators.

Effect of smoking on gingival crevicular fluid cytokine profile during experimental gingivitis

BACKGROUND

Cigarette smoking is a significant risk factor in the pathogenesis of periodontal disease, able to influence both the subgingival microbiota and host responses.

AIM

The aim of the present study was to determine the influence of smoking on the amount of IL-1beta, IL-4 and IL-8 in gingival crevicular fluid (GCF) during experimental gingivitis in humans.

MATERIAL AND METHODS

Twenty-two healthy subjects, 10 smokers and 12 non-smokers, participated in the study. After professional cleaning, they performed optimal hygiene to reach perfect clinical gingival health. Oral hygiene measures were ceased for a period of 10 days. Clinical indices, including plaque index (PI), gingival index (GI), probing pocket depth (PPD) and bleeding on probing (BOP), were assessed 2 days before (day -2), at the beginning (day 0) and at the end of the experimental gingivitis period (day 10). At the same time, GCF was collected from 12 sites in each patient, by means of durapore filter membranes. Total amounts of IL-1beta, IL-4 and IL-8 were determined by enzyme-linked immunoadsorbent assay.

RESULTS

Clinical data revealed that both smokers and non-smokers showed an increase in PI, GI and BOP scores during the experiment. Although no differences were noted with regard to PI at day 10, the GI and BOP were significantly less pronounced in smokers than non-smokers (p < 0.005). Non-smokers showed higher total amounts of IL-4 but lower amounts of IL-8 than smokers, throughout the experiment. Total amounts of IL-1beta and IL-8 increased significantly during plaque accumulation in both groups. IL-4 remained stable for the smoker group and decreased for the non-smoker group.

CONCLUSIONS

The present results indicate that smoking interferes with cytokine production. When performing studies regarding the pathogenesis of periodontitis, the smoking status of the participants needs to be taken into consideration.

Position Paper: Diagnosis of Periodontal Diseases

At the present time, the diagnosis and classification of periodontal diseases are almost entirely based on traditional clinical assessments. Supplemental quantitative and qualitative assessments of the gingival crevicular fluid and subgingival microflora can potentially provide useful information about the patient's periodontal disease. In certain situations, these supplemental risk-assessment tests may be particularly valuable in establishing the endpoint of therapy prior to placing patients on a periodontal maintenance program. Although the clinical utility of none of these tests has been validated, their further development is warranted. A genetic test for susceptibility to periodontitis has become commercially available. How best to use this and future host-based tests in clinical practice remains to be determined. Probing depth and clinical attachment loss measurements obtained with periodontal probes are practical and valid methods for assessing periodontal status. Computer-linked, controlled-force electronic periodontal probes are commercially available and are currently in use by some practitioners. Many of the logistical problems associated with subtraction radiography are being overcome and this powerful diagnostic tool may soon come into widespread use. Future developments in this and other imaging techniques are likely to have a profound effect on our approach to the diagnosis of periodontal diseases.

Bone turnover markers in serum and periodontal microenvironments

BACKGROUND

Periodontitis is characterized by altered bone turnover, but local measurements are difficult.

OBJECTIVES

The objective of this study was to develop a method to measure multiple markers of bone turnover from single samples collected at various bone surfaces of the periodontium, and to test the ratios of these markers against more traditional serum and gingival crevicular fluid (GCF) samples.

MATERIALS AND METHODS

Fourteen subjects with untreated periodontitis were recruited for sampling serum, GCF (from sites > or = 5 mm probing depth that bled on probing) and washes of periodontal bone surfaces (adjacent interproximal, vestibular cortical and trabecular bone) with a novel irrigating device. All samples were analyzed for osteocalcin (OC, bone turnover marker; RIA), cross-linked N-telopeptide of type I collagen (NTx, bone resorption marker; ELISA) and albumin (Alb, serum protein; ELISA). Results were reported as ratios: OC/NTx to determine relative bone turnover, and OC/Alb or NTx/Alb to determine local OC or NTx production.

RESULTS

The OC/NTx ratio was significantly higher (p < or = 0.05) in serum vs. GCF (OC undetectable), interproximal bone and cortical vestibular bone, but significantly lower than in trabecular vestibular bone. The OC/Alb ratio for serum was also statistically lower than for vestibular trabecular bone. The NTx/Alb ratio for serum was statistically lower than for GCF and all the bone wash test sites. The results indicated considerable local production of both OC and NTx.

CONCLUSIONS

This system demonstrated that multiple markers of bone turnover can be harvested by irrigation from periodontal bone microenvironments. Bone turnover profiles from periodontal bone surfaces and GCF differed from systemic bone turnover profiles (serum) and may be valuable in tracking site-specific responses to disease or treatment.

Evaluation of p53, bcl-2, and interleukin-15 levels in gingival crevicular fluid of cyclosporin A-treated patients

BACKGROUND

Apoptosis plays an important role in the maintenance of tissue homeostasis. Considering that apoptosis mediators may play a role in the pathogenesis of drug-induced gingival overgrowth, this study was conducted to evaluate p53, bcl-2, and interleukin-15 (IL-15) levels in gingival crevicular fluid (GCF) of cyclosporin A (CsA)-treated patients.

METHODS

Twenty renal transplant patients exhibiting CsA-induced gingival overgrowth and 15 systemically healthy gingivitis patients were included in the study; 15 systemically and periodontally healthy volunteer subjects served as the healthy control group. GCF samples were obtained from one interdental site with gingival overgrowth (GO+) and one site without (GO-) from each CsA-treated patient; hyperplasia index, probing depth, papilla bleeding index, and plaque presence were recorded. One site from each gingivitis patient and healthy control was selected, GCF samples were obtained, and the same clinical parameters were recorded. GCF p53, bcl-2, and IL-15 levels were analyzed by enzyme-linked immunosorbent assay. The results were tested statistically.

RESULTS

p53 and bcl-2 levels were below the minimum detectable level in all GCF samples analyzed. CsA GO+ and CsA GO- sites, as well as gingivitis sites, exhibited significantly higher GCF levels of IL-15 compared to healthy controls (P<0.05). The difference between CsA GO+ sites and gingivitis sites was not statistically significant, although the total amount of IL-15 in CsA GO+ sites was lower than gingivitis sites (P>0.05). The total amount of IL-15 in CsA GO- sites was significantly lower than gingivitis sites (P<0.05). No significant correlation was found between the clinical parameters and GCF IL-15 levels (P>0.05).

CONCLUSIONS

The pathogenesis of CsA-induced gingival overgrowth is multifactorial. The findings of the present study indicate that IL-15 may play a role in the pathogenesis of CsA-induced gingival overgrowth due to its interactions with CsA and its role in apoptosis and inflammation.

Effect of inflammation, smoking and stress on gingival crevicular fluid cytokine level

BACKGROUND

Recent studies have shown that cytokines are pivotal to the pathogenesis of periodontal diseases and may be used as markers in diagnosis.

AIM

The aim of the present study was to determine the levels of interleukin (IL)-1beta, IL-4, IL-6 and IL-8 in gingival crevicular fluid of periodontally healthy and diseased individuals and to study their association to smoking, stress and clinical periodontal parameters.

MATERIAL AND METHODS

A total of 80 patients were included in the study : 20 patients with early onset or aggressive periodontitis (EOP), 20 with chronic adult periodontitis (AP), 20 with gingivitis (G) and 20 patients with healthy periodontium (H). GCF was collected by means of Durapore strips, from four sites per patient, randomly selected in each quadrant. The contents of IL- 1beta, IL-4, IL-6 and IL-8 were measured in 320 samples by use of commercially available sandwich enzyme-linked immunoadsorbent assays.

RESULTS

In periodontally diseased subjects the total amounts of IL-1beta, IL-6 and IL-8 were significantly elevated as compared to healthy subjects, whereas IL-4 showed an inverse relationship to periodontal status and higher amounts were found in the healthy group. The amounts of all four cytokines were positively correlated with probing depths. IL-4, IL-6 and IL-8 were significantly correlated to smoking while stress was associated with IL-1beta, IL-6 and IL-8 levels.

CONCLUSIONS

The present data suggest that crevicular IL-1beta, IL-6 and IL-8 reflect the activity of periodontal destruction, whereas IL-4 shows an inverse correlation to it. The enhanced production of inflammatory cytokines in the presence of smoking and stress may have clinical consequences.

Effect of locally delivered minocycline microspheres on markers of bone resorption

BACKGROUND

Gingival crevicular fluid (GCF) biomarkers associated with bone resorption may be useful to determine periodontal disease status and response to therapy. The pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), a bone-specific degradation product, and interleukin 1-beta (IL-1), a potent bone-resorptive cytokine, have both been associated with periodontal disease activity. Minocycline is a tetracycline derivative possessing antimicrobial effects on periodontal pathogens and inhibitory properties on matrix metalloproteinases (MMPs) associated with tissue destruction. The aim of this study was to evaluate the effect of periodontal treatment in the form of scaling and root planing (SRP) and locally administered minocycline microspheres on the GCF levels of ICTP and IL-1.

METHODS

Forty-eight chronic periodontitis patients were randomly assigned to 2 groups (SRP plus subgingival application of vehicle control [SRP + V], or SRP plus subgingival application of minocycline microspheres [SRP + M]) and monitored at 8 sites per subject at baseline and 1, 3, and 6 months. Four shallow (PD < or = 3 mm) and 4 deep (PD > or = 5 mm) sites were evaluated for both marker levels and for probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). Eight periodontally healthy control subjects with no probing depths >3 mm and no loss of attachment were also monitored at the same time intervals. GCF levels of ICTP and IL-1 were determined using radioimmunoassay and enzyme-linked immunosorbent assay techniques, respectively.

RESULTS

Significant differences (P<0.001) in GCF levels of ICTP and IL-1 were found between deep and shallow sites at all time points in both treatment groups. In addition, healthy subjects demonstrated significantly reduced levels of both markers compared to both shallow and deep sites in periodontitis patients (P <0.001). Only the SRP + M treated patients exhibited significant reductions (P <0.05) in both ICTP and IL-1 levels 1 month after treatment. Furthermore, the SRP + M group demonstrated significantly lower IL-1 levels (P <0.02) at 1 month compared to the SRP + V group.

CONCLUSIONS

Results of this study indicate that GCF levels of ICTP and IL-1 correlate with clinical measures of periodontal disease and may aid in assessing disease status and response to periodontal therapy. Furthermore, local administration of minocycline microspheres led to a potent short-term reduction in GCF IL-1 levels. Additional studies are needed to address whether repeated administration of scaling and root planing along with minocycline microspheres will achieve long-term reductions in GCF ICTP and IL-1 levels.

Interleukin-1beta and thiobarbituric acid reactive substance (TBARS) levels after phase I periodontal therapy in patients with chronic periodontitis

BACKGROUND

Interleukin-1beta (IL-1beta), a potent stimulator of bone resorption, has been implicated in the pathogenesis of periodontal tissue destruction. There is also a clearly defined and substantial role for free radicals or reactive oxygen species in periodontal destruction. The thiobarbituric acid reactive substances (TBARS) is a commonly applied test to measure free radical activity. The aims of this study were to investigate the amount of crevicular IL-1beta, tissue TBARS levels, and the clinical status of patients with advanced chronic periodontitis and the effect of phase I periodontal therapy on these clinical parameters and measurements.

METHODS

Twenty-five chronic periodontitis and 25 healthy control (C) patients were selected for the study. Plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) were recorded from each sampling area. Gingival crevicular fluid (GCF) sampling and clinical index scores were recorded at the initial examination (IE) and 6 weeks after phase I periodontal therapy (APT). Assays for GCF IL-1beta were carried out by enzyme-linked immunosorbent assay (ELISA). Gingival tissue samples were obtained from sites requiring periodontal flap surgery due to unresolved pockets to determine the tissue TBARS levels. The paired-samples t test was used to compare the IL-1beta levels and clinical parameters between IE and APT. The independent-samples t test was used to determine the significance of all parameters between IE and C, and between APT and C. The correlation among the IL-1beta levels, clinical parameters, and tissue TBARS levels was analyzed using the Pearson correlation.

RESULTS

The concentration of IL-1beta levels was not statistically different among IE, APT, and C groups, but the total amount of IL-1beta levels was statistically different among the 3 groups. While the levels of IL-1beta and the clinical parameters were reduced following phase I periodontal treatment, pretreatment IL-1beta, post-treatment IL-1beta, and TBARS levels were statistically higher in IE and APT groups than C specimens. Tissue TBARS levels in the APT group were statistically greater than controls. No correlations were noted between tissue TBARS levels and clinical parameters in the APT group. A positive statistical correlation was detected between the total IL-1beta and TBARS levels in the APT group.

CONCLUSION

These data suggest that the levels of crevicular IL-1beta and gingival tissue TBARS are closely associated with periodontal status. This relationship may be valuable in treating and monitoring periodontal disease progression.

Evaluation of transforming growth factor-beta 1 level in crevicular fluid of cyclosporin A-treated patients

BACKGROUND

The aim of the present study was to investigate the level of transforming growth factor-beta 1 (TGF-beta 1) in gingival crevicular fluid (GCF) samples of cyclosporin A (CsA)-treated patients and to compare the results with control groups.

METHODS

Fourteen renal transplant patients exhibiting severe CsA-induced gingival overgrowth, 10 patients with chronic gingivitis, and 10 subjects with clinically healthy periodontium were included in the study. In CsA-treated patients, GCF samples were harvested from sites exhibiting gingival overgrowth (CsA GO+) and sites not exhibiting gingival overgrowth (CsA GO-). The TGF-beta 1 levels in a total of 96 GCF samples from the 34 participants were analyzed by enzyme-linked immunosorbent assay. The results were expressed in terms of total amount (pg/2 sites) and concentration (ng/ml).

RESULTS

TGF-beta 1 total amounts in CsA GO+ and CsA GO- sites were similar and significantly higher than that of healthy sites (P < 0.02 and P < 0.01, respectively). The total amount of TGF-beta 1 was also higher in gingivitis sites compared to the healthy sites, but the difference was not statistically significant (P > 0.05). CsA GO+ and CsA GO- sites exhibited higher total amount and concentration of TGF-beta 1 than that of gingivitis sites, but the differences were insignificant (P > 0.05).

CONCLUSIONS

The results of the present study support the theory that CsA increases the synthesis of TGF-beta 1 in GCF. However, since the difference between CsA GO+ and CsA GO- sites was not statistically significant, it seems unlikely that GCF TGF-beta 1 level is the sole factor responsible for the CsA-induced gingival overgrowth. Complex interactions between various mediators of inflammation and tissue modeling are possibly involved in the pathogenic mechanisms of this side effect.

Increased interleukin-1beta concentration in gingival crevicular fluid as a characteristic of periodontitis

BACKGROUND

The levels of interleukin-1beta (IL-1beta) have been reported to be higher in sites with periodontitis than in healthy controls. This may be the result of a more severe inflammation and/or constitutional differences in IL-1beta production. Our aim was to test the hypothesis that the level of IL-1beta in gingival crevicular fluid (GCF) is a characteristic trait of periodontitis, regardless of the degree of tissue destruction. As a secondary aim, we investigated the correlation between IL-1beta and neutrophil elastase. An untreated population was used.

METHODS

GCF samples from inflamed sites in 13 patients with gingivitis (GG), and from inflamed sites with shallow (GP) and deep (PP) pockets in 18 patients with periodontitis were collected. Interleukin-1beta, elastase-alpha-1-antitrypsin complex (E-A1AT), alpha-1-antitrypsin (A1AT), and alpha-2-macroglobulin (A2MG) were measured with ELISA. Elastase activity was measured with a specific substrate.

RESULTS

The concentration of IL-1beta was significantly higher in PP than in GG, but no significant differences were detected between PP and GP. A weak positive correlation between the elastase activity and IL-1beta was also observed. The elastase activity had a tendency to be higher in PP, although no significant difference was found among the 3 groups. The concentrations of E-A1AT, A1AT, and A2MG were similar in the 3 types of sites.

CONCLUSIONS

The levels of IL-1beta in GCF were increased in samples from periodontitis patients, regardless of the severity of disease at the sampled site, suggesting that the levels of IL-1beta are typical of a given patient.

Genetic variations in cytokine expression: a risk factor for severity of adult periodontitis

Periodontitis is a collection of chronic inflammatory diseases that are caused by specific bacteria. The bacteria activate inflammatory mechanisms in the periodontal tissues that destroy collagen and bone that support the teeth. Although bacteria are essential for the initiation of periodontitis, the quantity and types of bacteria have not been sufficient to explain the differences in disease severity. In recent years, it has become evident that for many common chronic diseases, there are modifying factors that do not cause the disease but rather amplify some disease mechanisms to make the clinical condition more severe. There are now data to suggest that a few factors which amplify the inflammatory process make people susceptible to an increased severity of periodontitis. Studies of untreated disease in Sri Lanka identified 3 patterns of disease progression. Studies in twins suggested that part of the clinical characteristics of periodontitis may be explained by genetic factors, but previous attempts to identify genetic markers for periodontitis have been unsuccessful Some genetic variations (polymorphisms) are commonly found in our population and represent a mechanism by which individuals may exhibit variations within the range of what is considered biologically normal. Since certain cytokines are key regulators of the inflammatory response and are important in periodontitis, we investigated the relationship between genetic variations associated with cytokine production and periodontitis severity. There are several polymorphisms in the cluster of genes that influence IL-1 biological activity. In recent clinical trials, two of these polymorphisms, when found together, have been associated with a significant increase in the risk for severe generalized periodontitis. Genetic association with periodontitis was evident only when smokers were excluded from the analysis, confirming the importance of smoking, and suggesting that both smoking and the IL- I genotype are independent factors in severe periodontitis. It is notable that 1 polymorphism associated with severe periodontitis in our study is also known to correlate with a 2- to 4-fold increase in IL-1 beta production. These findings are consistent with the current model of how genetic factors influence common chronic diseases. If we apply this model to periodontitis, it would involve the following: 1) a disease-initiating factor that would undoubtedly be specific bacteria such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans. and Bacteroides forsythus: and 2) modifiers of disease mechanisms that account for the clinical severity, including smoking, the IL-I genotype, certain systemic diseases, and psychosocial stress. The association of the IL-I genotype with severe periodontitis is consistent with several lines of periodontal research. Several studies have suggested there is a substantial genetic influence in periodontal disease. Although specific genetic markers have been identified in the uncommon juvenile forms of periodontitis, previous studies of specific genetic markers in adults with periodontitis have not been encouraging. Many investigators have, however, demonstrated a role for IL-1 in the initiation and progression of periodontitis. For example, IL-1 activates the degradation of the extracellular matrix and bone of the periodontal tissues, and elevated tissue or gingival fluid levels of IL-1 beta have been repeatedly associated with periodontitis. In addition, IL-1 is a strong enhancer of tissue levels of PGE2 and TNF-alpha. The association of severe periodontitis with smoking and the IL-1 genotype suggest a role for these factors in the pathogenesis of periodontitis. The finding that host modifying factors are associated with severe periodontitis suggest a biological mechanism by which some individuals, if challenged by bacterial accumulations, may have a more vigorous immunoinflammatory response, leading to more severe clinical disease. (ABSTRACT

Crevicular fluid interleukin-1beta, tumor necrosis factor-alpha, and interleukin-6 levels in renal transplant patients receiving cyclosporine A

Cyclosporine A(CsA) is successfully used to prevent graft rejection in organ transplantation and in the treatment of various systemic diseases. CsA-induced gingival overgrowth (CsA GO) is one of the most important side effects of this drug. However, the pathogenesis of this side effect is still unclear. It has been postulated that CsA-induced alterations of cytokine levels in gingival tissues might play a role in the drug-induced gingival overgrowth. The purpose of the present study was to determine the levels of interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and IL-6 in gingival crevicular fluid (GCF) samples from renal transplant patients receiving CsA therapy and exhibiting CsA GO. Sixteen renal transplant patients receiving CsA, 12 patients with gingivitis, and 11 periodontally healthy subjects were included in this study. Data were obtained on plaque index, papilla bleeding index (PBI), and hyperplastic index from each study site. GCF samples and clinical data were obtained from: 1) 2 sites exhibiting CsA GO (CsA GO+) and 2 sites not exhibiting CsA GO (CsA GO-) in each CsA-treated patient; 2) diseased sites in each patient with gingivitis; and 3) 2 healthy sites in each subject with clinically healthy periodontium. CsA GO+ and CsA GO- sites were also divided into 2 subgroups as clinically uninflamed (PBI = 0) and inflamed (PBI > or = 1). The total amounts of cytokines in GCF were assayed by enzyme-linked immunosorbent assay. GCF IL-1beta levels were significantly higher in CsA GO+ sites compared to CsA GO-sites. Higher GCF levels of IL-1beta and IL-6 were detected in diseased sites compared to healthy sites. Although GCF IL-1beta levels in CsA GO+ sites were significantly higher than in the diseased sites, IL-6 levels of these sites were lower than in the diseased sites, whereas clinical degrees of gingival inflammation were similar in CsA GO+ and diseased sites. Additionally, while IL-1beta and IL-6 levels were similar in uninflamed CsA GO- sites and healthy sites, IL-1beta levels were significantly higher in uninflamed CsA GO+ sites compared to healthy sites and uninflamed CsA GO- sites. However, IL-1beta and IL-6 levels were significantly higher in inflamed CsA GO- sites compared to uninflamed CsA GO+ sites. No significant changes in GCF TNF-alpha levels were found between the groups. These data indicate that CsA therapy does not increase IL-1beta and IL-6 levels in GCF directly and that gingival inflammation plays a significant role in the elevation of GCF IL-1beta and IL-6 levels. For this reason, it is suggested that the alterations of GCF IL-1beta and IL-6 levels in CsA-treated patients might be responsible for the CsA-induced gingival overgrowth not by itself but also in combination with other factors associated with inflammation. To our knowledge, this is the first report describing the levels of cytokines in GCF of CsA-treated patients. We believe that further studies will contribute to the description of the pathogenesis of CsA-induced gingival overgrowth.

Gingival crevicular interleukin-1 and interleukin-1 receptor antagonist levels in periodontally healthy and diseased sites

Interleukin-1 (IL-1) molecules, IL-1 alpha and IL-1 beta are cytokines involved in the acute-phase response against infection and in the pathogenesis of periodontal destruction. Administration of exogenous IL-1 receptor antagonist (IL-1ra) is effective in reducing the inflammatory reactions mediated by IL-1. However, the relationship between these three naturally occurring IL-1 molecules and periodontal diseases has been poorly characterized. We investigated the correlation of gingival crevicular IL-1 molecules and the clinical status of patients with different severities of periodontitis. IL-1 alpha, IL-1 beta, IL-1ra and the total IL-1/IL-1ra ratio (IL-1 activity index; IL-1AI) were measured in 75 gingival crevicular fluid (GCF) samples from non-inflamed gingiva sites in 2 healthy subjects and diseased sites in 7 patients with several types of periodontitis. IL-1 alpha, IL-1 beta and IL-1ra were measured by specific non-cross-reactive enzyme linked immunosorbent assay. The probing depth, gingival index and alveolar bone loss of each site was recorded at the time of GCF sampling. The total amount of IL-1 alpha, IL-1 beta and the IL-1AI, but not total IL-1ra, were found to be correlated with alveolar bone loss score. Three IL-1 molecules were also measured in the gingival tissue of patients with periodontitis. A similar progressive decrease of the IL-1AI was detected in gingival tissue with periodontitis. These results suggest that the amounts of both crevicular IL-1 and IL-1AI are closely associated with periodontal disease severity.

Factors affecting IL-1-mediated collagen metabolism by fibroblasts and the pathogenesis of periodontal disease: a review of the literature

Fibroblasts have been studied extensively for their contribution to connective tissue destruction in diseases where the metabolism of extracellular matrix components plays an essential part in their pathogenesis. A considerable dissolution, especially of collagen fibrils, is a well-known characteristic of the periodontal ligament and the gingival connective tissue in microbial-induced periodontal disease. Fibroblasts, responsible for the assembly of the extracellular matrix, are capable of responding directly to oral microbial challenges or indirectly, following activation of the host immune response, and can alter the composition of connective tissue in several ways: synthesis of inflammatory mediators, their receptors and antagonists; fibroblast proliferation; collagen synthesis; phagocytosis of collagen fibrils; and synthesis of proteolytic enzymes, including matrix metalloproteinases and their corresponding inhibitors. The contributions of these cellular fibroblastic properties to the pathogenesis of periodontal disease are reviewed in the context of the cytokine, interleukin-1, as the inflammatory regulator.

Interleukin-1 beta, prostaglandin E2, and immunoglobulin G subclasses in gingival crevicular fluid in patients undergoing periodontal therapy

Determination of the presence of inflammatory products found in gingival crevicular fluid (GCF) may be of value in evaluating both periodontal disease status and the outcome of therapy. Immunoglobulin G subclasses 1 through 4 (IgGs), interleukin 1-beta (IL-1 beta), and prostaglandin E2 (PGE2) have all been shown to be present in GCF. This study monitored IgGs, IL-1 beta, and PGE2 in GCF of 18 adult patients as they progressed through periodontal treatment toward maintenance therapy. Sites were selected from the most severely affected sextant as determined by probeable crevice depth (PD) at initial examination (IE). GCF was collected on four occasions: initial examination; 4 weeks after completion of initial therapy (oral hygiene counseling, and scaling and root planing); 3 months after completion of surgery; and 7 to 9 months later at a maintenance visit. All variables were reduced to binary form (positive or negative), and break points chosen to separate the approximately symmetrical bell-shaped areas (negatives) from the skewed tails (positives). Repeated measures analyses of variance were performed to detect significant changes in all variables across time. Significant improvements were observed for all the clinical variables measured: PD, attachment level, and bleeding on probing. However, significant reductions for the GCF components only occurred in the concentrations of IL-1 beta and PGE2, but were not evident until the maintenance sampling. Surprisingly, GCF:serum ratios of IgG subclasses did not change significantly over the course of the investigation. The robustness of the levels of these components may be due to inflammation associated with the healing process, or to a further plaque induced response.

The effects of smokeless tobacco on clinical parameters of inflammation and gingival crevicular fluid prostaglandin E2, interleukin-1 alpha, and interleukin-1 beta

The purpose of this study was to examine the effect of smokeless tobacco (ST) on gingival inflammation as assessed clinically and biochemically by gingival crevicular fluid (GCF) levels of PGE2, IL-1 alpha, and IL-1 beta. These parameters were compared in ST users (n = 12) and control, non-tobacco using subjects (n = 8) matched for plaque and probing depth levels. Both GI and GCF PGE2 concentration were significantly (P < 0.05) elevated at ST placement sites compared to sites in control subjects. A short-term longitudinal trial spanning 7 days also was undertaken within ST users (n = 18) to study the dynamics of gingival inflammation when ST is moved to a new site. At day 0 habitual ST placement sites exhibited a significantly (P < 0.05) higher GI compared to non-tobacco placement sites. Following transfer of ST to a new placement site, 48 hour GI scores were increased (P < 0.05) at this region. Although GCF parameters were not significantly altered, over 80% of the subjects developed dramatic inflammatory reactions in the alveolar mucosa, ranging from erythema to ulceration, at the new site of placement. This observation of a more severe response in alveolar mucosa compared to gingiva may be related to the physical location of ST or differences in tissue characteristics.

Histological evaluation of interleukin-1 beta and collagen in gingival tissue from untreated adult periodontitis

Interleukin-1 beta (IL-1 beta) may be related to the pathological processes associated with periodontitis, primarily due to its ability to induce collagenase, increase neutrophil chemotaxis, and stimulate bone resorption. This study was designed to histologically quantitate IL-1 beta positive cells from various histologic fields in untreated gingivitis/early periodontitis (G/EP) versus moderate/severe periodontitis (M/SP) gingival tissues, and associate these with collagen loss. Two gingival biopsies from 8 patients were collected, one from a G/EP site and one from a M/SP site. Mouse monoclonal antibodies in combination with an avidin-biotin-peroxidase system were used to stain for IL-1 beta, while the van Gieson method was used to stain for collagen in serial sections. Collagen loss in G/EP (35%) and M/SP (52%) fields was consistent with gingivitis and periodontitis, respectively. IL-1 beta positive cells in combined coronal/sulcular (Co/Su) and apical/sulcular (Ap/Su) fields (nearest the bacterial insult) were significantly more numerous compared to combined coronal/middle (Co/Mi) and apical/middle (Ap/Mi) fields (p < 0.05). While numbers and percentages of IL-1 beta positive cells were generally higher in M/SP biopsies, differences were not significant. Further, there was no correlation between the number of IL-1 beta positive cells and percent collagen loss. However, a significant correlation between IL-1 beta positive cells and corresponding gingival crevicular fluid IL-1 beta concentrations was noted (r = 0.65, p = 0.01). Through the use of immunohistochemistry, this study demonstrated that the presence of IL-1 beta + cells does not appear to have a direct association with collagen loss.