Longitudinal Comparison of Cytokines in Peri‐Implant Fluid and Gingival Crevicular Fluid in Healthy Mouths

Background: Peri‐implant and gingival tissues provide important sealing and protective functions around implants and teeth, but comparisons of the immunologic responses of these tissues after implant placement have not been conducted. Cytokine levels were measured in peri‐implant crevicular fluid (PICF) and gingival crevicular fluid (GCF) as surrogate measures of immune function at subcrestally placed dental implants and healthy periodontal sites during a 1‐year monitoring period. Methods: A total of 27 dental implants were placed subcrestally in 21 periodontally healthy patients (mean age: 49.0 ± 13.4 years). Repeated clinical and cytokine measurements were obtained over 12 months. GCF and PICF samples were collected and analyzed by cytokine microarray. Data were examined by non‐parametric analysis of variance. Results: Plaque and bleeding indices were similar among all patients (P >0.05) at baseline. During 1 year of monitoring, the mean volumes of PICF and GCF were similar (P >0.05). The levels of interleukin (IL)‐4, ‐6, ‐10, and ‐12p70, tumor necrosis factor‐α, and interferon‐γ in GCF and PICF were not significantly different and did not vary over time (P >0.05). The levels of IL‐1α were higher in GCF than PICF at 1, 2, 6, and 12 months, as were the levels of IL‐8 at 1, 2, 4, 6, and 12 months (P <0.001). Transforming growth factor‐β1 in PICF and GCF exhibited time‐dependent increases, and vascular endothelial growth factor was reduced at 1 year without differences between PICF and GCF (P >0.05). Conclusion: Within the limitations of this study design, it can be concluded that after subcrestal implant placement, the immune response of peri‐implant and periodontal tissues, as assessed by cytokine levels in PICF and GCF, is similar.     

Early wound healing following one-stage dental implant placement with and without antibiotic prophylaxis: a pilot study

BACKGROUND: One-stage implant placement has clinically acceptable treatment outcomes. Among other advantages, it may allow investigation of early wound healing. The purpose of this pilot study was to determine whether peri-implant crevicular fluid (PICF) can be used to detect early changes around implants placed with one-stage surgical protocol following 1 week of healing. METHODS: Twenty subjects (11 males and nine females; aged 22 to 72 years; two smokers) were included. Exclusion criteria were allergies to amoxicillin and systemic conditions that may affect healing. Subjects had a healthy periodontium and needed a single implant; eight received antibiotic prophylaxis, and 12 served as controls. Clinical healing was evaluated with plaque and gingival indices (PI and GI, respectively). Gingival crevicular fluid (GCF) from the surgical site was obtained prior to the surgery, whereas PICF was collected at the 1-week visit. Enzyme-linked immunosorbent assay was used to determine GCF/PICF interleukin (IL)-1beta and -8 concentrations. Peripheral blood and GCF antibiotic levels were measured by high-performance liquid chromatography. RESULTS: Postoperative PI and GI were slightly increased. Total GCF and PICF volumes did not show a significant difference between appointments. There was an increase in PICF IL-1beta and -8 levels at 1 week postoperatively. Mean amoxicillin serum concentration was 5.1 +/- 2 microg/ml at 1 to 4 hours following the initial dose, whereas GCF amoxicillin levels were below the limit of detection. Antibiotic prophylaxis had a modest effect on clinical indices (PI and GI) and no appreciable effect on biomarkers. CONCLUSIONS: PICF content can be studied as early as 1 week following one-stage implant placement. The results raise doubts regarding the clinical usefulness of amoxicillin prophylaxis.     

TNF-alpha TGF-beta2 and IL-1beta levels in gingival and peri-implant crevicular fluid before and after de novo plaque accumulation

Aims: The aim of this split‐mouth study was to investigate levels of tumour necrosis factor alpha (TNF‐α), transforming growth factor beta (TGF‐β2) and interleukin‐1 beta (IL‐1β) in gingival crevicular fluid (GCF) and peri‐implant crevicular fluid (PICF) after a 21‐day‐period of de novo plaque accumulation in the same patient. Material and Methods: In 25 patients, samples of GCF and PICF were collected in the sulcus of the tooth and of the implant after professional hygiene. After the no‐hygiene phase (21 days), second samples of GCF and PICF were taken. Third samples were collected after 69 days of re‐establishment oral hygiene techniques. The crevicular fluids were used to determine the volume and the levels of TNF‐α, TGF‐β2 and IL‐1β. Results: The volume of the crevicular fluids increased significantly after 21 days of plaque accumulation around teeth and implants and decreased significantly by 69 days. TNF‐α and TGF‐β2 did not change significantly among the three different samples. A significant increase of IL‐1β was observed after plaque accumulation around the teeth GCF, whereas in the PICF the increase was not statistically significant. Conclusions: These data suggest that increased volumes of GCF and PICF could be useful markers of early inflammation in gingival and peri‐implant tissues. In the presence of de novo plaque, implants showed lower, and nearly significant, levels of IL‐1β compared with teeth.     

Acute‐phase proteins and immunoglobulin G against Porphyromonas gingivalis in peri‐implant crevicular fluid: a comparison with gingival crevicular fluid

This investigation had 2 aims: 1) to determine the levels of acute‐phase proteins and immunoglobulin G (IgG) against Porphyromonas gingivalis in peri‐implant crevicular fluid (PICF) and their association with the clinical condition of the peri‐implant mucosa; and 2) to compare the inflammatory and immunological responses at implants and teeth as reflected by the gingival crevicular fluid (GCF) and PICF levels of acute‐phase proteins and immunoglobulins. Thirty‐one partially edentulous subjects were recruited for this study. PICF was sampled from 1 healthy and 1 inflamed site from each patient; GCF was sampled from an additional 21 healthy and 27 inflamed tooth sites of the same patients. GCF and PICF were collected with paper strips (for 30 s) and analysed using enzyme‐linked immunosorbent assays for α2‐macroglobulin, α1‐antitrypsin, transferrin, lactoferrin and IgG against P. gingivalis . This investigation demonstrated that the absolute amounts of the acute‐phase proteins and IgG against P. gingivalis are higher in GCF and PICF from inflamed than healthy sites. No significant differences were observed between PICF and GCF components at either healthy or inflamed sites, suggesting that inflammatory and immune events are similar in the peri‐implant mucosa and gingiva in humans and that PICF and GCF production is governed by similar mechanisms.     

Myeloperoxidase as a measure of polymorphonuclear leukocyte response in inflammatory status around immediately and delayed loaded dental implants: a randomized controlled clinical trial

Background: As well as gingival crevicular fluid (GCF), peri‐implant sulcus fluid (PISF) may have a potential diagnostic value for the early identification of metabolic and destructive processes. Purpose: The aim of this study was to analyze the potential impact of inflammation and loading on PISF myeloperoxidase (MPO) levels, in comparison with GCF. Materials and Methods: A total of 220 sites, dental implant (immediately [IL] or delayed loaded [DL]), and natural tooth, either healthy/noninflamed or gingivitis/inflamed, were classified. Clinical parameters were recorded, and GCF/PISF samples were obtained. GCF/PISF MPO levels were spectrophotometrically determined. Results: Clinical parameters demonstrated increases with the presence of gingival/peri‐implant inflammation. Total MPO levels were higher at inflamed tooth and implant sites compared to noninflamed/healthy sites (p < .05). Although they did not reach a significance level, inflamed IL sites had higher total MPO levels than inflamed DL sites (p = .401). Gingival index and total MPO levels exhibited significant correlations (p < .05). Conclusion: Using implants and natural teeth in the same study design, the findings of the present study support the close relationship between MPO production and inflammation, and may speculate a potential for loading of dental implants, contributing to the MPO content of PISF.     

Biomarkers and Bacteria Around Implants and Natural Teeth in the Same Individuals

Background: This cross‐sectional study assesses cytokine levels in peri‐implant crevicular fluid (PICF)/gingival crevicular fluid (GCF) and a selection of subgingival/submucosal plaque bacteria from clinically healthy or diseased sites in the same individuals. Methods: Samples from 97 implants/teeth (58 implants [19 healthy, 20 mucositis, 19 peri‐implantitis] and 39 natural teeth [19 healthy, 12 gingivitis, eight periodontitis] in 15 systemically healthy patients were investigated by immunoassay and real‐time polymerase chain reaction. Samples were obtained first, with probing depth, clinical attachment level, bleeding on probing, plaque index scores, and keratinized tissue width then recorded. Data were analyzed by Wilcoxon, Mann–Whitney U, and permutation tests on dependent, independent, and mixed dependent and independent samples and Spearman correlation. Results: Interleukin (IL)‐1β levels were significantly higher in PICF samples of healthy implants than in GCF samples of healthy teeth (P = 0.003), and soluble receptor activator of nuclear factor‐κB ligand (sRANKL) concentrations were significantly higher in the gingivitis than the mucositis group (P = 0.004). Biomarker levels were similar in peri‐implantitis and periodontitis groups (P >0.05). Actinomyces naeslundi and Streptococcus oralis levels were significantly higher in the healthy implant group than in healthy teeth (P <0.05). Prevotella intermedia and Treponema denticola (Td) levels were lower in the mucositis group than the gingivitis group (P <0.05). Prevotella oralis and S. oralis levels were significantly higher in the periodontitis group (P <0.05), and Td levels were significantly higher in the peri‐implantitis group (P <0.05). Conclusion: There were many similarities but, crucially, some differences in biomarker levels (IL‐1β and sRANKL) and bacterial species between peri‐implant and periodontal sites in the same individuals, suggesting similar pathogenic mechanisms.     

A Cross‐Sectional Assessment of Biomarker Levels Around Implants Versus Natural Teeth in Periodontal Maintenance Patients

Background: Recent studies point to the clinical utility of using peri‐implant sulcular fluid (PISF) as a valuable diagnostic aid for monitoring peri‐implant tissue health. The objectives of this study are to determine the levels of key biomarkers in PISF in periodontal maintenance participants and compare them with their corresponding levels in gingival crevicular fluid (GCF) obtained from the same participants. Methods: PISF and GCF were collected from an implant and a contralateral natural tooth after the clinical examination of 73 participants. The levels of interleukin (IL)‐1α, IL‐1β, IL‐6, IL‐8, IL‐10, IL‐12, IL‐17A, tumor necrosis factor (TNF)‐α, C‐reactive protein, osteoprotegerin, leptin, and adiponectin were determined using multiplex proteomic immunoassays. The correlation of biomarker concentrations between GCF versus PISF, within GCF or PISF, and with several covariates (age, brushing frequency, days since professional cleaning, probing depth [PD], and plaque index) were also determined. Results: Significantly higher levels of IL‐17A (P = 0.02) and TNF‐α (P = 0.03) were noted in PISF when compared with their levels in GCF. Significant positive correlations were noted between the concentrations of cytokines in PISF versus their levels in GCF. Among the covariates, a significant positive correlation was noted between mean PDs around implants and levels of IL‐1β (P <0.05) and IL‐8 (P <0.05) in PISF. Conclusion: The results of this study point to the differential expression of specific biomarkers in GCF versus their levels in PISF in periodontal maintenance patients, which is critical information before establishing PISF as a diagnostic fluid to monitor peri‐implant health.     

Analysis of cathepsin-K activity at tooth and dental implant sites and the potential of this enzyme in reflecting alveolar bone loss

Background: Cathepsin‐K is an enzyme involved in bone metabolism which may make this feature important for both natural teeth and dental implants. The aims of the present study are to comparatively analyze the gingival crevicular fluid (GCF)/peri‐implant sulcus fluid (PISF) cathepsin‐K levels of natural teeth and dental implants, and to assess the potential relationship between this biochemical parameter and alveolar bone loss around natural teeth and dental implants. Methods: Probing depth, bleeding on probing, gingival index, and plaque index clinical parameters were assessed, and GCF/PISF samples were obtained from natural teeth/dental implants presenting with either clinical health, gingivitis/peri‐implant mucositis, or chronic periodontitis/peri‐implantitis. Cathepsin‐K activity levels of 42 GCF samples and 54 PISF samples were determined, and marginal bone loss (MBL) measures were calculated from digitalized standardized intraoral periapical radiographs obtained from natural teeth and dental implants by using cemento‐enamel junction and the actual distance between two consecutive threads of the dental implant as reference points for natural teeth and dental implants, respectively. Results: Comparing the natural teeth group with dental implant group with regard to MBL measure, cathepsin‐K activity, and GCF/PISF volume revealed no significant differences. In both natural teeth and dental implant groups, despite higher MBL measures, cathepsin‐K activity, and GCF/PISF volumes with the presence of inflammation, it was the presence of alveolar bone loss that lead to significantly higher values for these parameters. Conclusion: We suggest cathepsin‐K as a biochemical parameter for monitoring periodontal/peri‐implant alveolar bone loss.     

Can Peri‐Implant Crevicular Fluid Assist in the Diagnosis of Peri‐Implantitis? A Systematic Review and Meta‐Analysis

Background: A broader understanding of the immune inflammatory profile of peri‐implant diseases could be helpful in the development of host‐targeted preventive and therapeutic strategies. The aim of this study is to answer two clinical questions: 1) whether patients with peri‐implantitis (PP) present higher prevalence of any specific inflammatory cytokine in peri‐implant crevicular fluid (PICF) compared with healthy patients; and 2) whether local inflammation measured in PICF can be used as a predictor for incipient PP. Methods: A systematic review of the literature on the most common cytokines released in PICF in healthy and PP‐affected sites was conducted from 1996 up to and including October 2013 using predefined search strategies. Cross‐sectional and prospective longitudinal studies were considered. Meta‐analyses were done separately for healthy, mucositis (MU), and PP outcomes. Results: Interleukin (IL)‐1β was the most studied cytokine (n = 12), followed by tumor necrosis factor (TNF)‐α (n = 10). Other cytokines were also linked to PP, such as IL‐4, IL‐6, IL‐8, IL‐10, IL‐12, and IL‐17. Statistical differences were revealed when IL‐1β release was compared between healthy implant sites and PP (P = 0.001) or MU sites (P = 0.002), respectively; when PP and MU were compared, no statistical differences could be detected (P = 0.80). For TNF‐α release, significant differences were found between healthy and PP implants (P = 0.02). Conclusions: PICF containing inflammatory mediators, such as IL‐1β and TNF‐α, can be used as additional criteria for a more robust diagnosis of peri‐implant infection. Additionally, once the inflammatory process is installed, no differences were found between peri‐implant MU and PP.     

Tissue inhibitor of metalloproteinases-1, matrix metalloproteinases-1 and -8, and collagenase activity levels in peri-implant crevicular fluid after implantation

The integrity of connective tissues surrounding dental implants may be influenced by a balance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). The purpose of this study was to provide an overall assessment of TIMP-1, MMP-1 and -8 levels as well as collagenase activities during the wound healing process after implantation and in peri-implantitis lesions. Peri-implant crevicular fluid (PICF) was sampled with sterile paper strips from 10 osseointegrated implants of 6 subjects. Ten implants from 6 patients affected with peri-implantitis were also assessed. Gingival crevicular fluid (GCF) from 11 periodontitis-affected patients and 10 healthy volunteers served as controls. TIMP-1 and MMP-1 and -8 protein levels in the PICF were measured by ELISA, and active and APMA-activatable collagenase activities were determined by functional assays using image-analysis after SDS-PAGE. The experiment showed a significant increase in the TIMP-1 level at 1 week after implantation as compared with that in GCF from healthy periodontium. Four weeks after implantation it had reached the same level as that in the GCF of healthy subjects. The data has also disclosed a higher post-implantation collagenase activity level at 1 week than at weeks 2, 4, and 12. This may be due to the increase in MMP-1 and -8. Furthermore, peri-implantitis and periodontitis were shown to be similar inflammatory lesions in respect to MMP-1 and -8 and collagenase activities, even though the TIMP-1/MMP-1 + MMP-8 ratio was significantly lower in peri-implantitis than in periodontitis. In conclusion, the overproduction of TIMP-1 in the wound area after implantation could, to some extent, inhibit excessive tissue destruction and degradation of the neo-matrix in wound repair due to MMPs.     

The Association Between Periodontal Inflammation and Labor Triggers (Elevated Cytokine Levels) in Preterm Birth: A Cross‐Sectional Study

Background: Periodontitis is considered to be a risk factor for preterm birth. Mechanisms have been proposed for this pathologic relation, but the exact pathologic pattern remains unclear. Therefore, the objective of the present study is to evaluate levels of four major labor triggers, prostaglandin E₂ (PGE₂), interleukin (IL)‐1β, IL‐6, and tumor necrosis factor (TNF)‐α, in gingival crevicular fluid (GCF) and serum samples between women with preterm birth (PTB) and full‐term birth (FTB) and correlate them with periodontal parameters. Methods: PGE₂, IL‐1β, IL‐6, and TNF‐α levels were estimated using enzyme‐linked immunosorbent assays in GCF and serum samples collected 24 to 48 hours after labor from 120 women (60 FTB, 60 PTB). Results: Women with PTB exhibited significantly more periodontitis, worse periodontal parameters, and increased GCF levels of IL‐6 and PGE₂ compared with the FTB group; there were no significant differences in serum levels of measured markers. GCF levels of IL‐1β, IL‐6, and PGE₂ and serum levels of TNF‐α and PGE₂ were significantly higher in women with periodontitis compared with periodontally healthy women. Serum levels of PGE₂ were positively correlated with probing depth (PD) and clinical attachment level (CAL) as well as with GCF levels of TNF‐α in women with PTB. Conclusions: Women with PTB demonstrated worse periodontal parameters and significantly increased GCF levels of IL‐6 and PGE₂ compared with those with FTB. Based on significant correlations among serum PGE₂ and PD, CAL, and GCF TNF‐α in PTB, periodontitis may cause an overall increase of labor triggers and hence contribute to preterm labor onset.     

Azithromycin as an Adjunctive Treatment of Generalized Severe Chronic Periodontitis: Clinical,Microbiologic, and Biochemical Parameters

Background: This study examines the efficacy of azithromycin in combination with non‐surgical periodontal therapy on clinical and microbiologic parameters and gingival crevicular fluid (GCF) matrix metalloproteinases‐8 (MMP‐8) levels over 6 months in patients with severe generalized chronic periodontitis (CP). Methods: Twenty‐eight of 36 patients with severe generalized CP were included in this randomized, double‐masked, placebo‐controlled, parallel‐arm study. They were randomly assigned to azithromycin or placebo groups (500 mg, once daily for 3 days). Probing depth (PD), clinical attachment level, dichotomous presence or absence of supragingival plaque accumulation, and bleeding on probing were recorded. GCF samples were obtained from one single‐rooted tooth with PD ≥ 6 mm, whereas microbiologic samples were collected from two single‐rooted teeth with PD ≥ 6 mm. Microbiologic parameters were analyzed by quantitative real‐time polymerase chain reaction for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia, and total bacteria. GCF MMP‐8 levels were determined by immunofluorescence assay. Results: Azithromycin and placebo groups demonstrated similar but significant improvements in all clinical parameters (P <0.05). A. actinomycetemcomitans, P. gingivalis, T. forsythia, P. intermedia, and total bacteria significantly decreased over the 6‐month period in both groups, whereas F. nucleatum was significantly reduced in all visits in the azithromycin group, with the levels also being lower compared with those of the placebo group (P <0.05). The azithromycin and placebo groups exhibited significant reduction in GCF MMP‐8 levels at the post‐treatment visit and at 2 weeks (P <0.05). Conclusion: On the basis of the present findings, it can be concluded that adjunctive azithromycin provides no additional benefit over non‐surgical periodontal treatment on parameters investigated in patients with severe generalized CP.     

Osteoprotegerin levels in peri-implant crevicular fluid

AIMS: To evaluate the levels of soluble receptor activator of nuclear factor-kappaB ligand (sRANKL) and osteoprotegerin (OPG) in crevicular fluid of endosseous dental implants. METHODS: Eighty-six implants in 39 patients were evaluated. All patients were treated with root-type implants placed at least 16 months and loaded at least 12 months before the examination. Peri-implant crevicular fluid (PICF) samples were obtained from buccal and lingual aspects of implants. Modified plaque index, probing depth, gingival index, and bleeding on probing (BOP) were recorded at four sites per implant. PICF levels of sRANKL and OPG were analysed by ELISA. Spearman's correlations were utilised to relate biochemical data and clinical parameters. RESULTS: The PICF level of sRANKL did not show significant correlation with the clinical parameters or the OPG level. The total amount of OPG was positively correlated with PICF volume, gingival index, and BOP (P<0.05) and negatively correlated with pack years (P<0.05). CONCLUSION: The findings of this preliminary study suggest that the crevicular fluid level of OPG deserves further investigation as a possible marker to evaluate the health status of surrounding tissues of dental implants, as this was not the case for the sRANKL level. Larger scale studies, particularly in peri-implantitis cases, may shed more light on this subject.     

The influence of academic stress on gingival inflammation

Abstract: Objective: The aim of the present study was to investigate the effects of academic stress on periodontal health, in relation to inflammatory markers in gingival crevicular fluid (GCF) and cortisol in saliva. Materials and methods: The study included 20 healthy dental hygienists (females: mean age 29.3 ± 8.5 SD) and was conducted during a major exam period and 4 weeks later after the exams. A clinical examination was performed and GCF was collected from four sites in each subject on these two occasions. Interleukin (IL)‐1β, IL‐4, IL‐6, IL‐10 levels were determined using Luminex 100 and cortisol amounts by radioimmunoassay (RIA ¹²⁵I). Students registered their perceived stress on a visual analogue scale (VAS). Significance of the findings was determined using paired t‐test, Wilcoxon‐matched pair and Spearman’s rank correlations. Results: Students had higher amounts of dental plaque (P < 0.007) and gingival inflammation (P < 0.001) during the exam period compared with after the exams. The amounts of IL‐6 and IL‐10 in GCF were significantly increased during the time of examinations. The median level of cortisol in saliva was also significantly raised during the exam period compared with after the exams, 20.52 nmol/l (range: 11.91–27.34) and 16.41 nmol/l (range: 10.91–24.17) respectively, P < 001. The results from the VAS registration revealed a significant difference (P < 001) between the two occasions. Conclusion: Academic stress appears to affect periodontal health, shown by more plaque accumulation, gingival inflammation and increased amounts of IL‐6, IL‐10 in GCF and cortisol in saliva.     

Interleukin-33 levels in gingival crevicular fluid, saliva, or plasma do not differentiate chronic periodontitis

Background: This study investigates whether gingival crevicular fluid (GCF), saliva, and plasma levels of interleukin‐33 (IL‐33) can differentiate individuals with chronic periodontitis from individuals with healthy periodontium. Methods: GCF, whole saliva, and plasma samples together with full‐mouth clinical periodontal recordings were obtained from 32 otherwise healthy, non‐smoker chronic periodontitis individuals and 25 systemically and periodontally healthy, non‐smoker individuals. IL‐33 levels in the biofluid samples were determined by enzyme‐linked immunosorbent assay. Data were tested statistically by Mann‐Whitney U test. Results: The GCF concentrations of IL‐33 were significantly lower in chronic periodontitis individuals than in healthy individuals (P <0.0001), whereas the total amounts in GCF samples were similar (P >0.05). The salivary and plasma contrations of IL‐33 were indifferent in the two study groups (P >0.05). Conclusions: According to the present findings, the GCF, saliva or plasma levels of IL‐33 could not differentiate chronic periodontitis individuals and periodontally healthy individuals. Larger‐scale intervention studies may better clarify this issue.     

Cytokine profile in the gingival crevicular fluid of rheumatoid arthritis patients with chronic periodontitis

The aim was to assess the cytokine profile in the gingival crevicular fluid (GCF) of rheumatoid arthritis (RA) patients with chronic periodontitis (CP). Databases were searched from 1991 to August 2013 using a combination of various keywords. Eight studies were included. The GCF concentrations of interleukin (IL)‐1β, IL‐4, IL‐10, matrix metalloproteinase (MMP)‐8, MMP‐13 and tumor necrosis factor‐alpha (TNF‐α) were reported to be higher in patients with RA than in healthy controls (HC) without CP. In one study, TNF‐α levels in GCF were significantly higher in HC than in RA patients receiving anti‐TNF‐α therapy. One study reported no significant difference in GCF TNF‐α levels among RA patients and HC regardless of anti‐TNF‐α therapy. One study reported no difference in IL‐1β and prostaglandin E₂ levels among RA patients and HC with CP. Raised levels of proinflammatory cytokines are exhibited in the GCF of RA patients with CP.     

Expression of HMGB1 and HMGN2 in gingival tissues, GCF and PICF of periodontitis patients and peri-implantitis

Background and objective

High mobility group chromosomal protein B1 (HMGB1) and N2 (HMGN2), two members of high mobility group (HMG) family, play important role in inflammation. The purpose of this study was to investigate the expression of HMGB1 and HMGN2 in periodontistis.

Materials and methods

The expression of HMGB1 and HMGN2 mRNA in gingival tissues and gingival crevicular fluid (GCF) in chronic periodontitis (CP), generalised aggressive periodontitis (G-AgP) patients and healthy subjects was detected by real-time PCR. The protein level of HMGB1 and HMGN2 in peri-implant crevicular fluid (PICF), peri-implant crevicular fluid of peri-implantitis (PI-PICF) and normal patients was determined by Western blotting. Furthermore, IL-1β, IL-6, IL-8, TNF-α and HMGB1 levels in GCF, PI-PICF and healthy-PICF samples from different groups were determined by ELISA.

Results

HMGN2 expression was increased in inflamed gingival tissues and GCF from CP and G-ApG groups compared to control group. HMGB1 expression was the highest in the gingival tissues and GCF from CP patients and was accompanied by increased concentrations of IL-1β, IL-6, IL-8 proinflammaory cytokines.

Conclusion

To our knowledge, this is the first study reporting that the expression of HMGB1 and HMGN2 was increased in the gingival tissues and GCF in CP and G-AgP and the PICF in PICF. Our data suggest that HMGB1 may be a potential target for the therapy of periodontitis and PI.     

Chemerin as a Novel Crevicular Fluid Marker of Patients With Periodontitis and Type 2 Diabetes Mellitus

Background: The objectives of the present study are to: 1) determine whether gingival crevicular fluid (GCF) chemerin is a novel predictive marker for patients with chronic periodontitis (CP) with and without type 2 diabetes mellitus (t2DM); 2) analyze the relationship between chemerin and interleukin (IL)‐6 in periodontally healthy individuals and in patients with CP and with and without t2DM; and 3) evaluate the effect of non‐surgical periodontal therapy on GCF chemerin levels. Methods: Eighty individuals were split into four groups: 20 who were systemically and periodontally healthy (CTRL), 20 with t2DM and periodontally healthy (DM‐CTRL), 20 systemically healthy with CP (CP), and 20 with CP and t2DM (DM‐CP). Individuals with periodontitis were treated with non‐surgical periodontal therapy. GCF sampling procedures and clinical periodontal measures were performed before and 6 weeks after treatment. Enzyme‐linked immunosorbent assay was used to measure chemerin and IL‐6 levels. Results: Greater values for GCF chemerin and IL‐6 levels were found in CP groups than in periodontally healthy groups, in DM‐CP than in CP, and in DM‐CTRL than in CTRL (P <0.008). GCF chemerin and IL‐6 levels decreased following therapy in CP groups (P <0.02). A comprehensive overview of all groups showed a statistically significant positive correlation of chemerin with IL‐6, glycated hemoglobin, sampled‐site clinical attachment level, and gingival index (P <0.05). Conclusions: In this study, periodontitis and t2DM induced aberrant secretion of chemerin, and non‐surgical periodontal therapy influenced the decrease of GCF chemerin levels in patients with CP with and without t2DM. Furthermore, it suggests GCF chemerin levels may be considered a potential proinflammatory marker for diabetes, periodontal disease, and treatment outcomes.     

Azithromycin concentrations in blood and gingival crevicular fluid after systemic administration

Background: Azithromycin is a macrolide antibiotic that is active against several periodontal pathogens. Macrolides are taken up and concentrated inside gingival fibroblasts, which could influence their pharmacokinetics. This study tests the hypothesis that steady‐state levels of azithromycin are higher and more sustained in gingival crevicular fluid (GCF) than in serum. Methods: Four healthy patients received an initial dose of 500‐mg azithromycin followed by 250‐mg doses on each of the next 2 days. Serum and GCF samples were obtained 2 hours after the last dose on day 2, and on days 4 and 7. GCF samples were collected from maxillary posterior sites with paper strips. The strips were pooled and eluted with high‐purity water. After extraction, the azithromycin content of the serum samples and GCF eluates was determined with an agar diffusion bioassay. Results: On days 2, 4, and 7, the concentrations of azithromycin in blood serum were 0.22 ± 0.02, 0.08 ± 0.02, and 0.04 ± 0.01 μg/mL, respectively. The concentrations in GCF were 8.82 ± 1.25, 7.90 ± 1.72, and 7.38 ± 1.15 μg/mL, respectively. Mean GCF levels were significantly higher than mean serum levels (P ≤0.02; paired t test). Conclusions: The findings demonstrate that the pharmacokinetic profiles of azithromycin are different in GCF and serum. At steady state, azithromycin concentrations in GCF were higher and more sustained than those in serum. Based on previous studies, the levels observed in GCF were above the minimal inhibitory concentration for Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and Prevotella intermedia.     

Interleukin‐6 Family of Cytokines in Crevicular Fluid of Renal Transplant Recipients With and Without Cyclosporine A–Induced Gingival Overgrowth

Background: Interleukin (IL)‐6 family of cytokines, including IL‐6, oncostatin M (OSM), leukemia inhibitory factor (LIF), and IL‐11, have fibrogenic features. The current study determines gingival crevicular fluid (GCF) levels of fibrosis‐related IL‐6–type cytokines in cyclosporine A (CsA)–induced gingival overgrowth (GO). Methods: Eighty non‐smokers were included (40 CsA‐medicated renal transplant patients with GO [GO + ; n = 20] or without GO [GO?; n = 20], 20 individuals with gingivitis, and 20 healthy participants). Probing depth and plaque, papilla bleeding, and hyperplastic index scores were recorded. GCF samples were obtained from the mesio‐buccal aspects of two teeth. GCF IL‐6, IL‐1β, OSM, LIF, and IL‐11 levels were analyzed by enzyme‐linked immunosorbent assay. Results: The GO+ and GO? groups had higher IL‐6 total amounts than the healthy group (P <0.008). IL‐1β total amounts in the GO+ group were significantly higher than in both the healthy and GO? groups (P <0.008). OSM total amount was elevated in the GO+ and GO? groups compared with both the gingivitis and healthy groups (P <0.008). All groups had similar LIF and IL‐11 total amounts (P >0.008). Moderate positive correlations were detected among IL‐6, IL‐1β, OSM, and IL‐11 total amount in GCF and clinical parameters (P <0.05). Conclusions: IL‐6 and OSM increases in GCF as a result of CsA usage or an immunosuppressed state irrespective of the severity of inflammation and the presence of GO. The IL‐6 family of cytokines might not be directly involved in biologic mechanisms associated with CsA‐induced GO. Lack of an association between assessed IL‐6 cytokines and CsA‐induced GO might indicate distinct effects of these cytokines on fibrotic changes of different tissues.