Concentration of interleukin-1beta and neutrophil elastase activity in gingival crevicular fluid during experimental gingivitis

BACKGROUND, AIM: The aim of the present study was to measure interleukin-1beta concentrations and neutrophil elastase activity in gingival crevicular fluid (GCF) during experimental gingivitis in humans. MATERIAL AND METHODS: 12 healthy young men participated. After prophylaxis, they performed optimal hygiene to reach plaque and gingivitis indices of or approaching zero. All oral hygiene measures were then ceased for a period of 18 days. The Quigley-Hein plaque index (PLI) and Saxer & Mühlemann papillary bleeding index (PBI) were assessed. GCF samples were taken from the mesiobuccal site of two contralateral teeth in the upper jaw by means of periopapers at baseline and on days 3, 7, 14 and 18. After measuring the gingival crevicular fluid volume (GCFV) with the Periotron 8000, the samples were analyzed in our laboratory for the detection of IL-1beta concentration by ELISA. RESULTS: PLI and PBI showed a reduction prior to baseline reaching almost zero, both increasing from day 0 to day 18 (PLI=from 0.1 to 2.9, PBI=from 0 to 2.0). IL-1beta concentration increased from 229.25 ng/ml (day 0) to 526.13 ng/ml (day 18). Clinical data and IL-1beta concentrations were correlated with elastase activity (EA). No significant correlation could be demonstrated between the clinical parameters assessed and IL-1beta or EA (Spearman rank correlation coefficient). A correlation between GCFV and PBI from day 0 to day 18 could be demonstrated. CONCLUSION: Overall, both IL-1beta and EA showed an increase from baseline throughout the whole study.     

Interleukin-1beta, interleukin-12 and interleukin-18 levels in gingival fluid and serum of patients with gingivitis and periodontitis

INTRODUCTION: Cytokines are of major importance in periodontal disease progression. Interleukin-12 (IL-12) stimulates interferon-gamma production by T helper type 1 (Th1) cells while IL-18 induces Th1 responses when present with IL-12 but Th2 responses in the absence of IL-12. IL-1beta has been correlated with periodontal disease destruction. This study determined the local concentrations of these cytokines in sites of gingivitis and periodontitis. METHODS: Gingival crevicular fluid was collected from two sites in each of 10 gingivitis patients and from two gingivitis sites and two periodontitis sites from each of 10 periodontitis patients. Serum samples were also collected. IL-1beta, biologically active IL-12 p70, the IL-12 p40 subunit and IL-18 concentrations were determined by enzyme-linked immunoabsorbent assay. RESULTS: IL-1beta and IL-18 concentrations were higher in the gingival crevicular fluid from periodontitis patients than in that from gingivitis patients; IL-18 concentrations were higher than those of IL-1beta. Very little IL-12, either p40 or p70, was detected in the gingival crevicular fluid samples. In the serum, very low levels of cytokines were found. The level of serum IL-12 p40, however, was higher than in the fluid from periodontitis sites of periodontitis patients. CONCLUSION: The local production of IL-1beta and IL-18 in the gingival crevicular fluid increased with increasing inflammation and IL-18 was the predominant cytokine at both gingivitis and periodontitis sites. Very little IL-12 was detected with levels decreasing with increasing inflammation. These results suggest that there is an association between severity of periodontal disease and levels of IL-1, IL-12 and IL-18.     

Crevicular fluid myeloperoxidase at healthy, gingivitis and periodontitis sites

The volume and myeloperoxidase (MPO) activity of gingival crevicular fluid (GCF) collected with filter paper strips for 30 s from the sulcus of healthy, gingivitis and periodontitis sites of Chinese subjects were measured. MPO/site and MPO/microliter GCF were both greater at gingivitis and periodontitis sites than at healthy sites. Enzyme activity was similar at the 2 categories of diseased sites. Mean GCF volume and MPO activity were calculated for all samples from healthy, gingivitis and periodontitis sites with GI 0, 1, 2 and 0 + 1. GCF volume, MPO/site and MPO/microliter GCF all were greater at GI 2 than GI 0 or 0 + 1. These data indicate that increased GCF MPO previously observed at periodontitis sites is not specific to such sites. Rather increased GCF MPO likely occurs when additional polymorphonuclear leukocytes enter the sulcus as a result of gingival inflammation. A second sample was obtained from 22 sites 4 weeks after the initial collection. These samples were collected for 5 s rather than 30 s. The GCF volume, MPO/site and MPO/microliters GCF were each greater in samples collected for 30 s rather than 5 s. Correlation coefficients showed that the amount of GCF and MPO activity of the fluid collected for 5 s and 30 s was dependent upon the site even though the 5-s and 30-s samples were collected 4 weeks apart.     

Differences in the inflammatory response in young and old human subjects during the course of experimental gingivitis

The aim of the present experiment was to study changes in (i) the composition of the inflammatory cell infiltrates and (ii) levels of alpha 2-macroglobulin, lactoferrin and IgG subclasses in gingival crevicular fluid in young and old individuals during 3 weeks of plaque formation. To establish healthy gingival conditions, all subjects received professional tooth cleaning during a 4 week pre-experimental period. The experimental sites included the mesio-palatal, palatal, and disto-palatal surfaces of all teeth present in the 15...25 tooth region. At baseline (day 0) assessments of plaque and gingivitis, microbial sampling and gingival fluid assessment were performed and one gingival biopsy harvested from each subject. Following the baseline examination, the participants abolished mechanical tooth cleaning measures in the palatal and approximal surfaces of 15...25. The clinical examination and the gingival fluid measurement were repeated on days 7, 14 and 21 of no oral hygiene. The microbiological sampling and the biopsy procedure were repeated on days 7 and 21. The gingival crevicular fluid samples harvested from the old individuals had higher levels of alpha 2-macroglobulin and IgG3 compared to young subjects. The immunohistochemical analyses of the biopsies demonstrated that the gingival lesion representing the old individuals harbored a higher proportion of B-cells and a lower density of PMN cells compared to the infiltrate in the young group of subjects. It is suggested that differences exist in the inflammatory response to de novo plaque formation in young and old individuals.     

Crevicular fluid endothelin-1 levels in periodontal health and disease

Background and Objective:  Endothelin-1 is a 21-amino-acid peptide with multifunctional regulation. Initial research indicated that endothelin-1 levels in the gingival crevicular fluid from patients with chronic periodontitis were higher than those in the gingival crevicular fluid from healthy subjects. The aim of the present study was to assess the relationship between the clinical parameters and the concentrations of endothelin-1 within the gingival crevicular fluid from inflamed gingiva and periodontitis sites and, subsequently, after the treatment of periodontitis sites.
Material and Methods:  A total of 60 subjects were divided into three groups – healthy (group I), gingivitis (group II) and chronic periodontitis (group III) – based on gingival index, pocket probing depth and clinical attachment loss. A fourth group consisted of 20 subjects from group III, 6–8 wk after treatment (i.e. scaling and root planing). Gingival crevicular fluid samples collected from each patient were quantified for endothelin-1 using an enzymatic immunometric assay.
Results:  Endothelin-1 was not detected in any sample from any of the study groups.
Conclusion:  The results showed that all the gingival crevicular fluid samples were negative for the endothelin-1 molecule. Therefore, endothelin-1 cannot be considered as a potential biomarker of periodontal disease progression.     

Crevicular fluid levels of TGFbeta1 in drug-induced gingival overgrowth

OBJECTIVE: To determine if local, gingival crevicular fluid (GCF) levels of TGFbeta1 were altered in drug-induced gingival overgrowth. Patients and methods: GCF samples were collected on Periopaper strips from 45 renal transplant recipients who had been medicated with cyclosporin or cyclosporin in combination with other putative overgrowth-inducing drugs for a minimum of 6 months. Twenty-two subjects had gingival overgrowth while the other 23 patients showed no signs of gingival changes and constituted the medicated control group. Non-medicated controls consisted 20 periodontally healthy individuals who had never taken overgrowth-inducing drugs. GCF levels of TGFbeta1 and alkaline phosphatase, a marker of inflammation, were determined by enhanced chemiluminescence ELISA and enzyme activity assays, respectively. RESULTS: TGFbeta1 levels in GCF from overgrowth and non-overgrowth sites in overgrowth sufferers did not differ. However, there were significant differences in median concentration (P = 0.001) and GCF levels of TGFbeta1 per sample (P = 0.05) between study groups with overgrowth patients having higher amounts per sample and lower concentrations than medicated and healthy controls. Median levels of alkaline phosphatase per GCF sample differed between site (P = 0.01) with higher levels present at overgrowth sites. Despite this, the concentration of enzyme in GCF did not differ between site or patient group. CONCLUSIONS: GCF TGFbeta1 detected in overgrowth patients could reflect a higher level of gingival inflammation because of difficulties in plaque control consequent on the development of overgrowth. However, the higher local levels of total TGFbeta1 in overgrowth patients could indicate that it is a risk factor for developing gingival overgrowth.     

Relationship between substance P and interleukin-1beta in gingival crevicular fluid during orthodontic tooth movement in adults

Metabolism by peptidases plays an important role in modulating the levels of biologically-active neuropeptides, while that of substance P (SP), a component of gingival crevicular fluid (GCF), may potentiate the inflammatory process in orthodontic tooth movement. The aim of this study was two-fold: (1) to investigate GCF levels of SP and interleukin-1beta (IL-1beta) during human orthodontic tooth movement, and (2) to determine the correlation coefficients between SP and IL-1beta levels in the GCF. The subjects were 3 males, with a mean age of 21.3 +/- 2.8 years old, and 6 females, with a mean age of 23.1 +/- 2.4 years, undergoing orthodontic movement of a single tooth, with the contralateral tooth used as the control. GCF was sampled at the control and treatment (compression) sites before and 1, 4, 8, 24, 72, 120, and 168 hours after initiation of orthodontic treatment. Prevention of plaque-induced inflammation allowed assessment of the dynamics of mechanically stimulated SP and IL-1beta levels in the GCF, which were determined using enzyme-linked immunosorbent assay (ELISA) kits. GCF levels of SP and IL-1beta for the treated teeth were significantly higher (P < 0.001) than for the corresponding control teeth from 8 to 72 hours, and peaked at 24 hours. These results show that the amounts of SP and IL-1beta in GCF increase with orthodontic tooth movement, and indicate that such increases may be involved in inflammation in response to mechanical stress.     

Interleukin-1 alpha, interleukin-8 and interferon-alpha levels in gingival crevicular fluid

Cytokines play an important role in the pathology associated with chronic inflammatory diseases. We measured the total amounts [picograms (pg)] and concentrations (pg/μl) of interleukin-1 alpha (IL-lα), interleukin-8 (IL-8) and interferonalpha (IFN-α) in 20 s gingival crevicular fluid (GCF) samples obtained from 2 diseased and 2 healthy sites in 20 subjects with periodontitis, and from 2 healthy sites in 20 subjects without disease. Both the mean amount and concentration of IL-lα were significantly higher (p < 0.001) in diseased sites compared to healthy sites in subjects with disease. The results for IL-8 and IFN-α differed depending on the method of reporting. Whereas the amount of IL-8 was significantly higher (p < 0.01) in diseased sites, the mean concentration of IL-8 was lower compared to healthy sites. The mean amount of IFN-α was similar in health and disease; however, the concentration of IFN-alpha was significantly lower in diseased sites (p < 0.001) corresponding to the significant increase in crevicular fluid volume (p < 0.001). There were no significant differences in the amount or concentrations of the 3 cytokines between healthy sites from subjects with disease and healthy sites from healthy controls. The total amounts of both IFN-α and IL-8 were correlated between healthy and diseased sites in subjects. These data suggest that, while the disease status of a site is the major determinant of the levels of these cytokines locally, subjects with high levels of IL-8 and IFN-α in healthy sites also tend to have high levels of these cytokines in diseased sites. Finally, both the concentrations and total amounts of IL-8 and IFN-α were significantly correlated in diseased sites, suggesting that levels of these two cytokines rise or fall in tandem. The combination of decreased IL-8 and decreased IFN-α concentrations at diseased sites may reflect the reduced anti-bacterial host defense activity at that site.     

Effect of periodontal therapy on crevicular fluid interleukin-1beta and interleukin-10 levels in chronic periodontitis

OBJECTIVES: This study aimed to analyse the levels of the proinflammatory cytokine IL-1beta and the anti-inflammatory cytokine IL-10 in gingival crevicular fluid (GCF) of patients with chronic periodontitis prior to, and following, periodontal therapy for a period of 32 weeks. MATERIAL AND METHODS: GCF samples were obtained from 24 non-diseased and 72 diseased sites of 12 periodontal patients prior to as well as at 6, 16 and 32 weeks post-periodontal therapy. All sites received conventional periodontal treatment and IL-1beta and IL-10 levels (concentration and total amount) were determined by enzyme linked immunosorbent assay (ELISA). Additionally, probing pocket depth (PD), clinical attachment loss (CAL), gingival (GI) and plaque (PII) indices were evaluated pre-and post-therapy. RESULTS: IL-1beta was detected in 382 out of 384 samples, while IL-10 was detected in 337 out of 384 samples. The total amount of IL-1beta was significantly higher at diseased compared to non-diseased sites (p<0.01). Following therapy, IL-1beta total amounts were reduced, while IL-1beta concentration gradually increased. IL-10 total amounts (per 30 s sample) were similar in diseased and non-diseased sites, and following therapy they remained almost unchanged. By contrast, IL-10 concentration was significantly higher in non-diseased sites (p<0.01) and displayed a significant increase post-therapy. Moreover, IL-1beta concentration and total amount were significantly greater in smokers following therapy, while IL-10 total amount was significantly higher in non-smokers both prior to and following therapy. Total IL-1beta amounts were positively correlated with GI and Pll. A weak negative correlation between IL-1beta and IL-10 levels was noted (p<0.05). CONCLUSIONS: The data suggest that the total amount rather than the concentration of IL-1beta in GCF seemed to be closely associated with periodontal disease severity. Moreover, smoking status influenced IL-1beta and IL-10 levels. An inverse relationship between IL-1beta and IL-10 was evident.     

Bioassay of interleukin 1 (IL-1) in human gingival crevicular fluid during experimental gingivitis.

The cytokine IL-1 was demonstrated in crevicular fluid during a 14- and 21-day experimental gingivitis in healthy human volunteers. A sensitive and specific bioassay allowed detection of biologically active IL-1 at levels ranging from 0.18 ng/microliters at baseline to 1.70 ng/microliters in inflamed gingiva. Levels of IL-1 increased rapidly with plaque accumulation and in advance of the subsequent gingival inflammation, peaking within 7 days of the start of gingivitis. As changes in IL-1 were detected before clinically recognizable gingival changes, IL-1 may have potential as an early marker of gingival inflammatory changes.     

Crevicular fluid prostaglandin E2 levels in periodontitis-resistant and periodontitis-susceptible adults

Abstract. The aim of this cross-sectional study was to determine concentrations of prostaglandin E₂ (PGE₂) in gingival crevicular fluid (GCF) in a cohort of periodontal disease-resistant (PDR) adults with chronic gingivitis but with minimal evidence of bone loss, and to compare these data with GCF-PGE₂ levels in patients with untreated chronic adult periodontal disease (CAPD), 20 PDR and 35 CAPD subjects with mean (±se) ages 52. 4 (±2.9) and 43, 7 (±1.2) years respectively, were recruited, GCE was sampled from 6 sites in each PDR subject and 4 sites in each CAPD subject. The GCF-PGE2 concentrations were determined by enzyme immunoassay (Assay Designs), Whole mouth medians of sitespecific GCF-PGE; concentrations were calculated for each subject. The means of the median GCF-PGE: concentrations were: PDR 54.94±4.06 ng/ml; CAPD 41.57±2.91 ng/ml ( p =0.009). We hypothesise that the higher concentrations of PGE; in the PDR group may be associated with the proliferating pocket epithelia of the chronic gingivitis. In the CAPD cohort, there were no differences in GCFPGE: concentrations between subgroups of smokers ( n =13), ex-smokers ( n =11) and non smokers ( n =11), In the PDR cohort, 19/20 subjects were non-smokers.     

Assessment of complement cleavage in gingival fluid during experimental gingivitis in man

The cleavage of complement may be an important immunopathologic mechanism in the development of gingival inflammation. Utilizing the experimental gingivitis model, cleavage of C3, C4 and B was assessed in gingival fluid following abstention from oral hygiene. 4 male dental students performed stringent oral hygiene measures until the gingival index approached 0, then refrained from any oral hygiene for 21 days. Gingival fluid, sampled with filter paper strips from the mesial surface of all maxillary premolars at 0, 7, 14, and 21 days, was assayed for C3, C4 and B cleavage by multilayer crossed-immunoelectrophoresis. Clinical indices were assessed following gingival fluid sampling. The subjects, who were plaque-free (PI = 0) at the beginning of the study, showed significant plaque accumulation at day 21 (87% of sites with PI greater than or equal to 2). Approximately 90% of the sites were free from clinical inflammation (GI = 0) at the start, but gingivitis increased with time such that 25% of the sites had GI scores of 2 at day 21. Bleeding on probing to the base of the pocket was not observed at day 0, but was observed at 62% of sites by day 21. Statistical analyses showed that all 3 indices significantly increased with time. The %C3 cleavage increased from a mean of 24% at day 0, to 35%, 45% and then 57% at days 7, 14 and 21, respectively, and both days 14 and 21 demonstrated significantly greater C3 conversion than that seen at day 0. The Spearman rank-order correlation coefficient for %C3 conversion versus time was p = 0.52, significant at the p less than 0.0001 level.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of gingivitis in pre-school children and young adults

Earlier studies suggest that children and adults differ in the propensity to develop gingivitis when oral hygiene is abandoned. To confirm the existence of such a difference, a comparative study of pre-school children and young adults was made with objective registration methods. The author performed all registrations. After a period of intensive oral hygiene, all cleaning of teeth was discontinued for 21 days. The amount of bacterial plaque, the amount of gingival exudate and crevicular leukocytes and the bleeding tendency were registered on days 0, 7, 14 and 21. During the experiment the amount of bacterial plaque increased continously in both groups. The amount of gingival exudate and the tendency to gingival bleeding increased to high values in the adults, while only a small rise was seen in the children. The amount of crevicular leukocytes increased in both groups, but the increment was greater in the adults. A comparison concerning differences in gingival exudate and bleeding tendency between pre-school children and adults was undertaken for gingival units that showed a similar plaque development. Under these statistically acceptable prerequisites, it was shown that there is a real difference in the tendency to develop gingivitis between pre-school children and adults.     

Levels of TGFbeta1 in gingival crevicular fluid during a 21-day experimental model of gingivitis

OBJECTIVE: TGFbeta1 is a multifunctional growth factor with both pro- and anti-inflammatory properties. This study aimed to determine levels of TGFbeta1 in gingival crevicular fluid (GCF), serum and plasma in the early stages of gingival inflammation. DESIGN: A 21-day experimental model of gingivitis employing a split mouth design with a soft vinyl splint used to cover test teeth during brushing. SUBJECTS: Ten healthy volunteers (mean age 21 years; five males and five females). METHODS: GCF and blood (with and without EDTA) was collected on days 0, 7, 14 and 21. GCF volumes were measured on a precalibrated Periotron 8000TM. Clinical indices of gingival inflammation and plaque levels were obtained after GCF sampling. Normal brushing resumed after GCF collection on day 21 and final samples were collected on day 35. TGFbeta1 and alkaline phosphatase (ALP) levels were determined using enhanced chemiluminescent methods. RESULTS: Clinical indices and GCF volumes increased at test sites during the 21-day test period. Concentrations of TGFbeta1 and ALP in GCF (test and control), serum and plasma did not change throughout the study (P > 0.3). However, total amounts of TGFbeta1 (pg sample-1) and ALP (mu IU sample-1) in GCF increased at test sites and were significantly higher than baseline values at days 7, 14 and 21 (P < 0.04). Control sites showed no variation in TGFbeta1 or ALP levels throughout the study period (P > 0.35). All parameters at test sites returned to control levels at day 35 (P > 0.3). CONCLUSION: The data indicate that GCF TGFbeta1 levels increase early in plaque-induced inflammation. Whether the biological consequence of this site-specific increase is pro- or anti-inflammatory in nature remains to be elucidated.     

Non-redundant roles for interleukin-1 alpha and interleukin-1 beta in regulating human IgG2.

BACKGROUND: Serum concentrations of immunoglobulin G2 (IgG2) are elevated in localized aggressive periodontitis (LAgP) patients, and secretory products of monocytes from LAgP patients enhance IgG2 responses of lymphocytes from healthy subjects. Furthermore, genes regulating production of interleukin (IL)-1 influence the risk for both aggressive periodontitis (AgP) and chronic periodontitis. These observations, and the fact that IgG2 dominates responses to carbohydrates from Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis, prompted the hypothesis that IL-1 alpha, IL-1 beta, and IL-RA may help regulate human IgG2 responses. METHODS: Human peripheral blood leukocytes (PBL) were stimulated in culture with pokeweed mitogen (PWM); the levels of available IL-1 gene products were manipulated; and the effect on IgG2 production was monitored. Manipulations of IL-1 were accomplished by adding specific neutralizing monoclonal antibodies or recombinant IL-1RA, IL-1 alpha, or IL-1 beta. RESULTS: Blocking the IL-1 receptor with IL-1RA or neutralizing IL-1 alpha or IL-1 beta with specific antibody dramatically suppressed IgG2 production (50% to 70%). Additionally IL-1 alpha did not compensate for neutralized IL-1 beta, and additional IL-1 beta did not compensate for neutralized IL-1 alpha, suggesting the 2 monokines have separate roles in promoting IgG2. Furthermore, combinations of anti-IL-1 alpha and anti-IL-1 beta were more inhibitory than either antibody alone, and IL-1 alpha and IL-1 beta in combination appeared to work additively in promoting IgG2. Moreover, PBL cultures from a group of LAgP patients with high IgG2 levels had elevated levels of IL-1 beta. CONCLUSION: IL-1 alpha and IL-1 beta appear to have critical and non-redundant roles in the generation and regulation of potent IgG2 responses, which appear to be important in human responses to carbohydrate-bearing bacteria.     

Estimation of interleukin-1beta levels in the gingival crevicular fluid in health and in inflammatory periodontal disease

Initial research indicated that the levels of interleukin-1beta (IL-1beta) are higher in sites of inflammation than in healthy sites. However, subsequent studies suggest heterogenous responses and indicate the quantitative levels of IL-1beta to be the characteristic of an individual rather than simply being the reflection of the inflammatory status of the tissues. This study has been designed to find out the relationship between IL-1beta levels in the gingival crevicular fluid and the inflammatory status of the periodontal tissues in the Indian population. Sixty patients were selected for the study. They were categorized in to three groups based on their periodontal tissue status as group I (clinically healthy gingiva with no loss of attachment), group II (gingivitis with no attachment loss) and group III (gingivitis with attachment loss). Microcapillary pipettes were used to collect gingival crevicular fluid samples from one site in each person and the samples were analysed for IL-1beta using a commercially available ELISA kit. The concentration of IL-1beta in the gingival crevicular fluid of patients in group III is statistically higher (P < 0.0001) than that in group II and the concentration of IL-1beta in groups II and III is statistically at much higher levels (P < 0.0001) than in the group I subjects. However, there is a significant overlap in the values obtained in groups II and III and the values in both the groups range over a wide spectrum. The composite values obtained within the groups and the overlapping values in groups II and III could indicate the role of genetic polymorphism in determining the quantity of IL-1beta produced and also the contributory role of other cytokines that share similar biologic activity.     

Daytime variations of interleukin-1beta in gingival crevicular fluid

Interleukin-1 β (IL-1 β ) is an important parameter in periodontal research because of its role in inflammation and bone resorption. One measure used to assess local IL-1 β concentrations is analysis of its levels in gingival crevicular fluid (GCF). While studies on serum IL-1 β concentrations indicate a circadian rhythm of this parameter, nothing is known about daytime variations of IL-1 β in GCF. The present study thus aimed to analyse such variations. Daytime variations of GCF-IL-1 β between 08:00 and 22:00 h were assessed, with a time resolution of 2 h, in 28 periodontally healthy subjects.The data showed a significant variation throughout the day, with the lowest concentrations and total amounts in the morning and the highest in the evening. The effect sizes of comparisons between morning and evening samples were medium to high and corresponded in magnitude to those reported in other published research comparing healthy sites and those affected by periodontitis. The smallest daytime variations were found to occur between 12:00 h and 18:00 h. It is concluded that daytime variations in GCF-IL-1 β are large enough to be able to mimic or mask differences caused by clinical factors.     

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.