Gingival crevicular fluid matrix metalloproteinase-8 levels following adjunctive use of meloxicam and initial phase of periodontal therapy

Importance of Metalloproteinase 8 (MMP-8) in the Diagnosis of Periodontitis

Periodontitis is a complex condition. Left untreated, it leads to tooth loss and the need for prosthetic treatment. The incidence of periodontitis is steadily increasing, so new methods are being sought to aid in the diagnosis of the disease. Among the methods postulated is the determination of concentrations of bioactive compounds which include extracellular matrix metalloproteinases (MMPs). These enzymes are present in various structural elements of the stomatognathic system. The most promising enzyme of this group appears to be metalloproteinase 8 (MMP-8). MMP-8 assays are performed in gingival fluid or saliva, and MMP-8 levels have been shown to be higher in patients with periodontitis compared to healthy subjects and correlated with some clinical parameters of the condition and the severity of the disease. In addition, the preliminary usefulness of this enzyme in evaluating the effectiveness of periodontal treatment and doxycycline therapy has been demonstrated. Determination of the active form of MMP-8 (aMMP-8) in oral rinse fluid using off-the-shelf assays shows the highest potential. Despite reports about aMMP-8 and promising data on the role of MMP-8 in periodontal diagnosis, a clear determination of the usefulness of this enzyme requires further research.

Efficacy of MMP-8 Level in Gingival Crevicular Fluid to Predict the Outcome of Nonsurgical Periodontal Treatment: A Systematic Review

Purpose: To explore whether baseline matrix metalloproteinase (MMP)-8 level in gingival crevicular fluid (GCF) (exposure) can predict the outcome (reduction in probing pocket depth (PPD) (outcome)) of nonsurgical periodontal therapy (NSPT) (manual or ultrasonic or both) in patients with periodontitis (population/problem) after 3 months. Methods: Six databases (PubMed, Cochrane library, ProQuest, Ovid, Scopus, EBSCO) were searched for relevant articles published until 30 July 2021. Retrieved articles were passed through a three-phase filtration process on the basis of the eligibility criteria. The primary outcome was the change in PPD after 3 months. Quality of the selected articles was assessed using Cochrane Risk of Bias tool (RoB2) and Risk of Bias In Non-Randomized Studies of Interventions (ROBINS-I) tools. Results: From 1306 articles, five were selected for analysis. The results showed high variations in the level of GCF MMP-8 level at baseline. The average amount of reduction in PPD was 1.20 and 2.30 mm for pockets with initial depth of 4−6 mm and >6 mm, respectively. Conclusion: On the basis of available evidence, it was not possible to reach a consensus on the ability of baseline GCF MMP-8 to forecast the outcome of NSPT. This could have been due to variation in clinical and laboratory techniques used. However, consistency in mean PPD reduction after 3 months was shown.

Filifactor alocis and Tumor Necrosis Factor-Alpha Stimulate Synthesis of Visfatin by Human Macrophages

There is little known about the effect of the periodontopathogen Filifactor alocis on macrophages as key cells of the innate immune defense in the periodontium. Therefore, the aim of the present study was to investigate the effect of F. alocis and additionally of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNFα) on visfatin and other pro-inflammatory and proteolytic molecules associated with periodontitis in human macrophages. The presence of macrophage markers CD14, CD86, CD68, and CD163 was examined in gingival biopsies from healthy individuals and periodontitis patients. Human macrophages were incubated with F. alocis and TNFα for up to 2 d. The effects of both stimulants on macrophages were determined by real-time PCR, ELISA, immunocytochemistry, and immunofluorescence. F. alocis was able to significantly stimulate the synthesis of visfatin by human macrophages using TLR2 and MAPK pathways. In addition to visfatin, F. alocis was also able to increase the synthesis of cyclooxygenase 2, TNFα, and matrix metalloproteinase 1. Like F. alocis, TNFα was also able to stimulate the production of these proinflammatory and proteolytic molecules. Our results highlight the pathogenetic role of F. alocis in periodontal diseases and also underline the involvement of visfatin in the aetiopathogenesis of periodontitis.

Regulation of Cyclooxygenase 2 by Filifactor alocis in Fibroblastic and Monocytic Cells

Periodontitis is a prevalent chronic inflammatory disease triggered by a synergistic and dysbiotic microbiota present in the oral biofilm. This in vitro study is aimed at evaluating the regulation of cyclooxygenase (COX)2 expression and production by the periodontopathogen Filifactor alocis in human gingival fibroblastic (HGF-1) and monocytic (THP-1) cells and also at investigating the underlying cellular pathway mechanisms. HGF-1 and THP-1 cells were exposed either to F. alocis or to the proinflammatory cytokine tumor necrosis factor alpha (TNFα) for 1 and 2 d to examine the COX2 expression by qPCR. COX2 protein levels were evaluated by ELISA in F. alocis-stimulated cells. Both types of cells were also stimulated with a blocking toll-like receptor (TLR)2 antibody or specific inhibitors against MAPKs. F. alocis significantly (p < 0.05) increased COX2 at both transcriptional and protein levels in both HGF-1 and THP-1 cells. Moreover, the stimulatory effect of F. alocis on COX2 was more pronounced in HGF-1 cells in comparison to THP-1 cells. F. alocis upregulated the COX2 expression in a dose-dependent manner in both type cells at 1 d. TNFα also significantly (p < 0.05) increased the COX2 expression in both cells. After preincubation of HGF-1 and THP-1 cells either with a neutralizing anti-TLR2 antibody or with specific MAPK inhibitors, the F. alocis-upregulated COX2 expression was significantly (p < 0.05) suppressed at 1 d. Our in vitro study provides original evidence that F. alocis stimulates COX2 production in fibroblastic and monocytic cells through TLR2 and MAPK mechanisms, suggesting a role of this periodontopathogen in the etiopathogenesis of periodontitis.

Novel meloxicam releasing electrospun polymer/ceramic reinforced biodegradable membranes for periodontal regeneration applications

Periodontal disease is associated with the destruction of periodontal tissues, along with other disorders/problems including inflammation of tissues and severe pain. This paper reports the synthesis of meloxicam (MX) immobilized biodegradable chitosan (CS)/poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) based electrospun (e-spun) fibers and films. Electrospinning was employed to produce drug loaded fibrous mats, whereas films were generated by solvent casting method. In-vitro drug release from materials containing varying concentrations of MX revealed that the scaffolds containing higher amount of drug showed comparatively faster release. During initial first few hours fast release was noted from membranes and films; however after around 5h sustained release was achieved. The hydrogels showed good swelling property, which is highly desired for soft tissue engineered implants. To investigate the biocompatibility of our synthesized materials, VERO cells (epithelial cells) were selected and cell culture results showed that these all materials were non-cytotoxic and also these cells were very well proliferated on these synthesized scaffolds. These properties along with the anti-inflammatory potential of our fabricated materials suggest their effective utilization in periodontital treatments.

An appraisal of innovative meloxicam mucoadhesive films for periodontal postsurgical pain control: A double-blinded, randomized clinical trial of effectiveness

Background and Objective:

Transmucosal analgesic delivery is a promising approach to periodontal postoperative pain management. The purpose of this clinical trial is to appraise the effectiveness of transmucosal drug delivery system with meloxicam films and to identify its minimum effective dosage via this route after periodontal flap surgery.

Materials and Methods:

The analgesic mucoadhesive films were formulated using meloxicam and hydroxypropyl methyl cellulose polymer by solvent casting method. The sample size consisted of 60 chronic periodontitis patients who require periodontal flap surgery. The subjects were randomized using lottery method into four groups (Group A - 45 mg; B - 30 mg; C - 20 mg; D - 10 mg meloxicam per film). After periodontal flap surgery, the respective meloxicam mucoadhesive films were placed over the surgical site and were removed on 4^th day of postsurgery. The primary outcome measure was postsurgical pain level and recorded at 1^st, 2^nd, 3^rd, 4^th, 5^th, 24^th, and 48^th h using a 0–10 mm visual analog scale with markings from 0 = no pain to 10 = extreme pain.

Results:

The postoperative pain control observed in Groups A and B was found to be effective, and the patient comfort level was very satisfactory. Whereas in Group C, it was found to be high in the first 3 h postsurgically, after which adequate pain relief was seen. Group D exhibited inadequate pain relief. No adverse reactions were noted after applying the film in any of the groups.

Conclusion:

Transmucosal delivery of meloxicam was found to be effective and safe in postsurgical pain control of periodontal flap surgery. The minimum effective dosage via this route for meloxicam was found to be with 30 mg mucoadhesive films.

Serum and salivary matrix metalloproteinases, neutrophil elastase, myeloperoxidase in patients with chronic or aggressive periodontitis

Salivary, serum matrix metalloproteinase-8 (MMP-8), tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), neutrophil elastase (NE), and myeloperoxidase (MPO) levels were investigated in generalized chronic periodontitis (GCP), generalized aggressive periodontitis (GAgP), and healthy groups. Whole-mouth clinical periodontal measurements were recorded. Salivary, serum concentrations of MMP-8, MPO, TIMP-1, and NE were determined by immunofluorometric assay or ELISA in 18 patients with GCP, 23 patients with GAgP, 18 individuals with healthy periodontium. Patients in the GAgP group were younger than the other groups (p<0.05). The study groups were similar in gender, smoking status. Plaque index was higher in GCP than GAgP group (p<0.05). Biochemical data were similar in periodontitis groups. Salivary, serum MPO, and salivary NE concentrations were higher; TIMP-1 concentrations were lower in the periodontitis groups than the controls (p<0.05). The present data support a close relationship between salivary, serum protease content and clinical periodontal parameters in patients with generalized periodontitis.

Comparative study to investigate the effect of meloxicam or minocycline HCl in situ gel system on local treatment of periodontal pockets

In situ gelling formulations allow easy application to the target area. Gelation is induced by physiological stimuli at the site of application where the formula attains semisolid properties and exerts sustained drug release. In situ gelling formulations containing either 3% meloxicam (Mx) or 2% minocycline HCl (MH) were prepared for local application into the periodontal pockets. Gel formulations were based on the thermosensitive Pluronic(®) (Pl) and the pH-sensitive Carbopol(®) (C) polymers. C gels were prepared in combination with HPMC (H) to decrease its acidity. The total percent drug released from Pl formulae was 21.72% after 1 week for Mx and 85% after 3 days for MH. Their release kinetics data indicated anomalous non-Fickian behavior that could be controlled by both diffusion and chain relaxation. Addition of MH to C/H gels (1:2.5) resulted in liquefaction, followed by drug precipitation. Regarding C/H gel containing Mx, it showed a prolonged release rate up to 7 days with an initial burst effect; the kinetics data revealed Fickian-diffusion mechanism. The in vitro antibacterial activity studies for MH gel in Pl revealed that the drug released exceeded the minimum inhibitory concentration (MIC) of MH against Staphylococcus aureus ATCC 6538; placebo gel showed no effect on the microorganism. Clinical evaluation of Pl gels containing either Mx or MH showed significant improvement in chronic periodontitis patients, manifested by decrease in pocket depth and gingival index and increase in bone density.

Effect of scaling and root planing on interleukin-1β, interleukin-8 and MMP-8 levels in gingival crevicular fluid from chronic periodontitis patients

BACKGROUND AND OBJECTIVE

  There are few data concerning the effect of scaling and root planing on the levels of immune and inflammatory mediators in gingival crevicular fluid from patients with chronic periodontitis. Therefore, in this study the influence of scaling and root planing was determined on amounts of interleukin (IL)-1β, IL-8 and MMP-8 in gingival crevicular fluid from patients with chronic periodontitis, in relation to clinical parameters.

MATERIAL AND METHODS

  A total of 51 patients were enrolled in this study. The study population consisted of 30 patients with generalized advanced chronic periodontitis, while 21 periodontally healthy subjects were recruited for the control group. The clinical parameters included approximal plaque index, gingival index, pocket depth and clinical attachment loss. The amounts of IL-1β, IL-8 and MMP-8 in gingival crevicular fluid were measured by ELISA. Periodontal parameters as well as gingival crevicular fluid humoral factor amounts were evaluated in the control group and in chronic periodontitis patients at baseline and at 1 and 4 wk after scaling and root planing treatment.

RESULTS

  At baseline, there were significant differences between control subjects and chronic periodontitis patients in terms of clinical attachment loss, pocket depth, gingival index (p < 0.001) and approximal plaque index (p < 0.01). The amounts of IL-1β, MMP-8 (p < 0.001) and IL-8 (p < 0.01) in gingival crevicular fluid were significantly lower in healthy subjects than in chronic periodontitis patients. Scaling and root planing led to improvement in all examined clinical parameters, apart from clinical attachment loss. Periodontal treatment also resulted in a significant decrease in the amounts of IL-1β, IL-8 and MMP-8 in comparison to baseline, especially 4 wk after scaling and root planing (p < 0.001); however, the amounts of these humoral factors were still higher than those in control group.

CONCLUSION

Our observations indicated that short-term nonsurgical therapy resulted in a significant improvement in periodontal indices and in a marked decrease of IL-1β, IL-8 and MMP-8 gingival crevicular fluid levels. Nevertheless, no significant correlations were found between clinical parameters and amounts of humoral factors after therapy.

Role of polymorphonuclear neutrophils in the clearance of Enterococcus faecalis derived from saliva and infected root canals

OBJECTIVES

The goal of this study was to measure (1) the ability of polymorphonuclear neutrophil leukocytes (PMNs) to kill oral Enterococcus faecalis strains, (2) up-regulation of inflammatory mediators by PMNs in interaction with E. faecalis, and (3) the ability of E. faecalis to cause inflammation in mouse muscle tissue.

METHODS

Fifteen endodontic and nine saliva strains of E. faecalis were isolated and identified by specific 16S ribosomal RNA (16S rRNA) primers. The bacteria were grown in BHI broth and incubated with mouse PMN in appropriate media to determine the ability of the PMNs to kill the bacteria. In other experiments up-regulation of interleukin (IL)-1α, tumor necrosis factor α (TNF-α), matrix metalloproteinase-8 (MMP-8), and cyclooxygenase (COX)-2 messenger RNA in the PMNs was measured after exposure of the leukocytes to the bacteria using real-time polymerase chain reaction. Finally, the inflammatory potential of and PMN response to E. faecalis suspension in mouse muscle tissue was examined from histological sections using hematoxylin-eosin staining and immunostaining.

RESULTS

Murine PMNs killed about 80% of the E. faecalis cells in 1 hour, irrespective of the source of isolation of the strains. Quantitative PCR results showed that IL-1α, TNF-α, MMP-8, and COX-2 messenger RNA were markedly up-regulated in E. faecalis-stimulated PMNs or in E. faecalis-invaded muscular tissues. MMP-8 messenger RNA level was positively related to COX-2 messenger RNA level. Histological evaluation and immunostaining disclosed that all E. faecalis strains could recruit PMNs to the local infectious sites and cause abscess formation.

CONCLUSION

E. faecalis strains from saliva and infected root canals have the potential to recruit PMNs in the infectious sites leading to inflammation via up-regulation of PMN IL-1α, TNF-α, MMP-8, and COX-2. PMNs can play an important role in killing of E. faecalis.

Host-derived diagnostic markers related to soft tissue destruction and bone degradation in periodontitis

BACKGROUND

A major challenge in clinical periodontics is to find a reliable molecular marker of periodontal tissue destruction with high sensitivity, specificity and utility.

OBJECTIVES

The aim of this systematic review is to evaluate available literature on 'the utility of molecular markers of soft and hard periodontal tissue destruction'.

MATERIALS AND METHODS

Based on the focused question, 'What is the utility of molecular markers of soft and hard periodontal tissue destruction', an electronic and manual search was conducted for human studies presenting clinical data for the potential of molecular markers of tissue destruction in biofluids; gingival crevicular fluid (GCF), saliva, and serum.

RESULTS

Papers fulfilling the inclusion criteria were selected. All relevant data from the selected papers were extracted and recorded in separate tables for molecules in GCF, saliva, and serum.

CONCLUSION

Within the defined limits of the Problem/Population, Intervention, Comparison, Outcome, the present analysis reveals that (a) no single or combination of markers exists that can disclose periodontal tissue destruction adequately; (b) while the most fruitful source of biomarkers for periodontal destruction appears to be in molecules tightly related to bone and soft tissue destruction, this remains to be objectively demonstrated. Currently, clinical measurements are still the most reliable.

What do 'omic technologies have to offer periodontal clinical practice in the future?

BACKGROUND AND OBJECTIVE

Periodontal diseases are the most common chronic inflammatory diseases of humans and a major cause of tooth loss. Inflammatory periodontitis is also a complex multifactorial disease involving many cell types, cell products and interactions. It is associated with a dysregulated inflammatory response, which fails to resolve, and which also fails to re-establish a beneficial periodontal microbiota. There is a rich history of biomarker research within the field of periodontology, but exemplary improvements in analytical platform technologies offer exciting opportunities for discovery. These include the 'omic technologies, such as genomics, transcriptomics, proteomics and metabolomics, which provide information on global scales that can match the complexity of the disease. This narrative review focuses on the recent advances made in in vivo human periodontal research by use of 'omic technologies.

MATERIAL AND METHODS

The Medline database was searched to identify articles currently available on 'omic technologies with regard to periodontal research.

RESULTS

One hundred and sixty-one articles focusing on biomarkers of and 'omic advances in periodontal research were analysed for their contributions to the understanding of periodontal diseases.

CONCLUSION

The data generated by the use of 'omic technologies have huge potential to inform paradigm shifts in our understanding of periodontal diseases, but data management, analysis and interpretation require a thoughtful and systematic bioinformatics approach, to ensure meaningful conclusions can be made.

Association of gingival crevicular fluid biomarkers during periodontal maintenance with subsequent progressive periodontitis

BACKGROUND

The analysis of biomarkers in gingival crevicular fluid (GCF) may be helpful in forecasting patient vulnerability to future attachment loss. The purpose of this study is to correlate GCF biomarkers of inflammation and bone resorption with subsequent periodontal attachment and bone loss in a longitudinal trial of a matrix metalloproteinase (MMP) inhibitor.

METHODS

GCF was collected from two periodontal pockets (mean +/- SD: 5.1 +/- 1.0 mm) at baseline and annually in postmenopausal females with moderate to advanced periodontitis undergoing periodontal maintenance every 3 to 4 months during a 2-year double-masked, placebo-controlled, randomized clinical trial of subantimicrobial dose doxycycline (SDD; 20 mg two times a day). Subjects were randomized to SDD (n = 64) or a placebo (n = 64). GCF was analyzed for the inflammation markers interleukin (IL)-1beta (using enzyme-linked immunosorbent assay), total collagenase activity (using hydrolysis of a synthetic octapeptide), and MMP-8 (using a Western blot) and the bone-resorption marker carboxyterminal telopeptide cross-link fragment of type I collagen (ICTP) (using a radioimmunoassay). Generalized estimating equations were used to associate these biomarkers, categorized into tertiles, with subsequent clinical attachment (using an automated disk probe) or interproximal bone loss (using radiography). Odds ratio (OR) values compared highest to lowest tertile groups.

RESULTS

Increases in GCF IL-1beta and MMP-8 during the first year of periodontal maintenance were associated with increased odds of subsequent (year 2) periodontal attachment loss (OR = 1.67; P = 0.01 and OR = 1.50; P = 0.02, respectively) driven by the placebo group. Elevated baseline ICTP was also associated with increased odds of 1- and 2-year loss of alveolar bone density (OR = 1.98; P = 0.0001) in the placebo group, not the SDD group, and a loss of bone height (OR = 1.38; P = 0.06), again driven by the placebo group.

CONCLUSION

These data support the hypothesis that elevated GCF biomarkers of inflammation and bone resorption from a small number of moderate/deep sites have the potential to identify patients who are vulnerable to progressive periodontitis, and SDD may modify that risk.

Application of the checkerboard immunoblotting technique to the quantification of host biomarkers in gingival crevicular fluid

BACKGROUND

The aim of this study was to describe the development and validation of the checkerboard immunoblotting (CBIB) technique for the high-throughput quantification of multiple inflammatory mediators in gingival crevicular fluid (GCF) samples.

METHODS

Monoclonal antibodies were used to bind GCF interleukin (IL)-1beta and -8 and matrix metalloproteinase (MMP)-8 to the surface of membranes. Biotinylated antibodies were used to detect bound antigens in a checkerboard format. Signals were developed using chemiluminescence, captured on film, and quantified using software for array analysis. The assay was tested for potential cross-reactions among the three pairs of antibodies. Eleven CBIBs were processed to determine the analytical sensitivity of the assay. Forty GCF samples were analyzed using CBIB and enzyme-linked immunosorbent assay (ELISA) in parallel, and the significance of the correlations among the results was tested using the Pearson correlation coefficient. Nine hundred thirty-one GCF samples were collected from 20 periodontally healthy subjects and 20 periodontitis subjects and analyzed using CBIB to test the assay's sensitivity and dynamic ranges using clinical samples.

RESULTS

The CBIB was capable of distinguishing among the three analytes. The sensitivity and dynamic ranges of the assay were suitable for the detection of the three targets in the majority of GCF samples. There were highly statistically significant (P <0.0001) positive correlations between CBIB and ELISA data for all three biomarkers. The periodontitis subjects had statistically significantly higher mean levels of IL-1beta and -8 compared to healthy subjects.

CONCLUSION

The CBIB technique is a sensitive and specific assay for the high-throughput quantification of MMP-8 and IL-8 and -1beta in GCF.

Gingival crevicular fluid prostaglandin E(2) and thiobarbituric acid reactive substance levels in smokers and non-smokers with chronic periodontitis following phase I periodontal therapy and adjunctive use of flurbiprofen

BACKGROUND

It has been established that smoking is an important risk factor for the initiation and progression of chronic periodontitis (CP). This study investigates the effects of phase I periodontal therapy and adjunctive flurbiprofen administration on prostaglandin E(2) (PGE(2)) and thiobarbituric acid reactive substance (TBARS) levels in gingival crevicular fluid (GCF) samples from smoker and non-smoker patients with CP.

METHODS

Twenty-one non-smoker and 21 smoker patients with CP were divided into four groups according to treatment modalities. Group 1 (non-smokers with CP) and group 3 (smokers with CP) patients received daily 100-mg flurbiprofen tablets in a 2 x 1 regimen for 10 days together with scaling and root planing (SRP). Patients in group 2 (non-smokers with CP) and group 4 (smokers with CP) received placebo tablets in a 2 x 1 regimen for 10 days together with SRP. Plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) measurements were recorded and GCF samples were collected at baseline and on day 10 of drug intake from each sampling area by a single examiner who was unaware of the treatment modality. Assays for GCF PGE(2) and TBARS were carried out by an enzyme-linked immunosorbent assay and fluorometric method, respectively.

RESULTS

All groups showed statistically significant reductions in PI and GI scores following the phase I periodontal treatment on day 10 (P <0.05), but no statistical differences were observed in PD and CAL scores after the therapy. In groups 1 and 2, the reduction of GCF PGE(2) and TBARS levels were not significant after the therapy compared to baseline levels. In group 3, GCF PGE(2) and TBARS levels exhibited a statistically significant decrease (P <0.05) after the therapy. Group 4 showed significant reductions (P <0.05) in GCF PGE(2) levels after the therapy. No statistically significant reductions were observed in group 4 with regard to GCF TBARS levels. When groups 1 and 3 were compared according to GCF TBARS levels after the therapy, a more statistically significant reduction was observed in group 3 (P = 0.001).

CONCLUSION

These results suggest that additional flurbiprofen administration may have more inhibitory effects on GCF levels of PGE(2) and TBARS in the groups of smokers compared to non-smokers with CP.

Analgesic and anti-inflammatory dose–response relationship of 7.5 and 15mg meloxicam after lower third molar removal: a double-blind, randomized, crossover study

Fifty patients were scheduled to undergo removal of symmetrically positioned lower third molars in two separate appointments. Meloxicam 7.5 or 15 mg was once daily administered in a double-blind, randomized and crossover manner after the surgery for 4 days. Objective and subjective parameters were recorded for comparison of postoperative courses. Patients treated with 7.5mg meloxicam who underwent osteotomy reported higher pain scores at 1.5, 3, 4, 10, 12 and 16 h (P<0.05) and ingested a greater amount of rescue analgesic medication (P<0.05) than those who did not require osteotomy. A higher percentage of patients who underwent osteotomy medicated with 7.5mg meloxicam needed rescue medication as compared to those who did not require osteotomy (P<0.05). There was a similar mouth opening at suture removal compared with preoperative values for both doses (P>0.05). There were no significant differences concerning swelling observed on the 2nd or 7th postoperative days in comparison with baseline (P>0.05) between the two doses. Pain, trismus and swelling after lower third molar removal not requiring osteotomy can be successfully controlled by a dose regimen of 7.5mg meloxicam once daily. For more aggressive extractions 15 mg meloxicam is advisable.

Increased local matrix metalloproteinase-8 expression in the periodontal connective tissues of smokers with periodontal disease

Matrix metalloproteinase (MMP)-8 has been associated with the progression of periodontitis, a common inflammatory disease of the supporting structures of the teeth, and with other degradative diseases. Tobacco smokers are at high risk of developing periodontitis that may progress more rapidly and respond poorly to treatment. Therefore, MMP-8 expression was determined by immunofluorescence staining in 60 random, computer-selected fields in the excised periodontal tissues of smokers and non-smokers, balanced for age, gender, and periodontal status. Immunofluorescence intensity, representing MMP-8 expression, in the periodontal tissues of smokers (30 fields from 6 subjects, mean 1154+/-124 units) was significantly higher than that in the periodontal tissues of non-smokers (30 fields from 6 subjects, mean 817+/-60 units; p < 0.05). Serum MMP-8 concentrations were measured by ELISA and compared in a larger group of smokers (n = 20) and age- and gender-balanced non-smokers (n = 20). Systemic MMP-8 concentrations in smokers and non-smokers were not significantly different (p > 0.05). A local tobacco-related increase in MMP-8 burden may contribute to periodontal disease progression in tobacco smokers. This finding may also have relevance to other tobacco-induced inflammatory diseases, such as vascular and pulmonary diseases.

The effect of topical doxycycline usage on gingival crevicular fluid MMP-8 levels of chronic and aggressive periodontitis patients: a pilot study

The aim of this study was to evaluate the efficacy of topical subgingival application of doxycycline hyclate (DH) gel adjunctive to non-surgical periodontal therapy on gingival crevicular fluid (GCF) matrix metalloproteinase (MMP)-8 levels in chronic and aggressive periodontitis patients. Forty teeth of 10 chronic periodontitis patients and 32 teeth of eight aggressive periodontitis patients were screened for 6 months. Scaling and root planing (SRP) was applied to the control sites and DH gel adjunctive to SRP was applied to the test sites of each patient simultaneously. GCF MMP-8 levels were analysed at baseline, 7 days; and at 1, 3 and 6 months by Sandwich Elisa Method. At 1, 3 and 6 months, probing depth (P < 0.0051) and plaque scores and bleeding on probing values (P = 0.000) significantly decreased in each group when compared with the baseline, but there was no statistically significant difference between the test and control sites. GCF MMP-8 levels reduced presenting statistically significant differences on 7 days, 1, 3 and 6 months in four of the groups (P < 0.05); however, intergroup differences were not statistically significant. Developing functional and immunological-based chair-side MMP tests might serve as useful adjunctive diagnostic tools when monitoring the effects of DH gel application.

Effects of selective cyclooxygenase-2 inhibitor and omega-3 fatty acid on serum interleukin-1beta, osteocalcin, and C-reactive protein levels in rats

BACKGROUND

The aim of this study was to evaluate the effects of selective cyclooxygenase-2 inhibitor, celecoxib, and omega-3 fatty acid on serum levels of interleukin 1-beta (IL-1beta), osteocalcin (OC), and C-reactive protein (CRP) in experimental periodontitis.

METHODS

Experimental periodontitis in rats was induced by repeated injection of purified lipopolysaccharide (LPS) derived from Escherichia coli endotoxin. Forty-seven adult male Sprague-Dawley rats were divided into five study groups as follows: saline control, LPS, LPS + celecoxib, LPS + omega-3 fatty acid, and LPS + celecoxib + omega-3 fatty acid. Celecoxib and omega-3 fatty acid were given alone or in combination during 14 days of the experimental study period. At the end of the 2-week protocol, serum samples were obtained, and the rats were sacrificed. Serum samples were analyzed for IL-1beta, OC, and CRP concentrations by enzyme-linked immunosorbent assay. Defleshed jaws were analyzed morphometrically for alveolar bone loss. Data were evaluated statistically by non-parametric tests.

RESULTS

According to the morphometric measurements, the LPS and drug treatment groups showed significantly higher bone loss than the saline control group (P <0.05). Omega-3 fatty acid, both alone and in combination with celecoxib, revealed significantly higher IL-1beta levels than LPS and celecoxib groups (P <0.05). Individual and combined administration of celecoxib and omega-3 fatty acid significantly increased OC levels compared to the LPS group (P <0.05). There were no significant differences in serum CRP levels.

CONCLUSIONS

Celecoxib and/or omega-3 fatty acid administration does not significantly influence circulating levels of CRP. The significantly increased serum OC level observed after individual and combination administration suggests that celecoxib and omega-3 fatty acid may influence bone remodeling and thereby inhibit the progression of alveolar bone resorption. However, the failure to observe any significant inhibition of bone loss in celecoxib- and/or omega-3 fatty acid-treated rats compared to the LPS group suggests that their therapeutic effect may be reduced by other factors, such as increases in serum IL-1beta promoting osteoclast activity.

Selective cyclo-oxygenase 2 inhibition affects ileal but not colonic anastomotic healing in the early postoperative period

BACKGROUND

Selective cyclo-oxygenase 2 (COX-2) inhibitors are increasingly prescribed in the perioperative period. Recent recognition of a possible role for COX-2 in wound healing has raised concerns about the safety of their use in surgical practice. Therefore, the influence of celecoxib, a selective COX-2 inhibitor, on early anastomotic healing was investigated.

METHODS

Celecoxib, in doses of 15, 50 or 200 mg per kg per day, was given daily from the day before operation onwards to male Wistar rats that received both ileal and colonic anastomoses. Anastomotic strength was assessed by measuring the breaking strength and bursting pressure on the third day after operation. A second group received a dose of 50 mg per kg per day and a colonic anastomosis only, and healing was assessed on the third and fifth day after surgery.

RESULTS

Expression of COX-2 protein was upregulated in the anastomotic area. Administration of celecoxib, at all doses tested, resulted in a significantly higher ileal dehiscence rate than in control rats (P = 0.002). In contrast, colonic anastomoses healed normally within the same animals. The latter was confirmed in rats with colonic anastomoses only.

CONCLUSION

In this model, administration of the COX-2 inhibitor celecoxib affected ileal but not colonic anastomotic healing in the early postoperative period.

Host response modulation in the management of periodontal diseases

OBJECTIVE

To review the biological mechanisms and clinical utility of therapeutic modulation of the host response in the management of periodontal diseases.

MATERIAL AND METHODS

A search of MEDLINE-PubMed was performed up to and including December 2004. The search was limited to in vitro, experimental animal and clinical studies published in English. The selection criteria included all levels of available evidence: systematic reviews, randomised-controlled clinical trials, controlled clinical trials, prospective and retrospective cohort studies and case reports of human and experimental animal studies.

RESULTS

Six targets for non-microbial chemotherapeutic intervention were identified. Clinical trials have demonstrated the ability of non-steroidal anti-inflammatory drugs to slow periodontal disease progression. However, recently reported serious adverse effects preclude the use of cyclooxygenase-2 inhibitors as an adjunct to periodontal therapy. Adjunctive use of subantimicrobial dose doxycycline to non-surgical periodontal therapy is beneficial in the management of chronic periodontitis over 12 months. Controversial data exist on the effects of bisphosphonate administration as an adjunct to periodontal therapy. Evidence on modulation of other host mediators including lipoxins, cytokines and nitric oxide synthase is limited to animal research.

CONCLUSION

After validation in long-term clinical trials, adjunctive host modulation therapy may prove advantageous in the management of periodontal diseases.

Longitudinal analysis of metalloproteinases, tissue inhibitors of metalloproteinases and clinical parameters in gingival crevicular fluid from periodontitis-affected patients

BACKGROUND

The aim of this work was to improve the assessment of the periodontal disease status through measurements of extracellular matrix metalloproteinases (MMPs) and their tissular inhibitors (TIMPs) in the gingival crevicular fluid from patients diagnosed with chronic periodontitis.

METHODS

Gingival crevicular fluid samples from patients (n = 13) were taken from 60 sites initially, and from 51 and 41 sites, respectively, 3 and 6 months after scaling and root planing. Gingival crevicular fluid samples were also taken from healthy subjects (n = 11, 24 sites). The presence of MMP-9 and MMP-8 was assessed by zymography and immunowestern blotting, respectively. The actual MMP activity (gelatinase and collagenase) was measured using the fluorogenic substrate assay. TIMP-1 and -2 levels were measured by immunodot blot.

RESULTS

The fluorogenic substrate assay determinations showed higher MMP activity in sites with probing depth > or = 4 mm, with significant reduction post-treatment. Gelatinase activity followed by zymography consisted mainly of MMP-9. A different pattern of MMP-8 in control and patient sites was found. Controls only showed species of a partially active form (69 kDa), whereas patient sites showed a high frequency of the active form (56 kDa), and in some cases the latent form (85 kDa) was also observed. The active form reduced its frequency in sites with probing depth > or = 4 mm. TIMP-1 and -2 levels in patients were significantly lower than in controls, and after treatment the recovery of TIMP-1 level similar to control was observed.

CONCLUSION

Significant correlations between the severity of the periodontal disease and the actual MMP activity, the active form of MMP-8 and the low level of both TIMP-1 and TIMP-2 were found.

In vitro studies of a degradable device for controlled-release of meloxicam

BACKGROUND

Plaque biofilm and associated host responses are the primary factors in the pathogenesis of periodontitis. Delivery of medications directly into the periodontal pockets to suppress or eradicate the pathogenic microbiota or modulate the inflammatory response has attracted significant interest to limit periodontal tissue destruction. The aim of the present study was twofold: (1) to describe the development of a biodegradable controlled-release device containing meloxicam as the therapeutic agent and (2) to evaluate the in vitro release of meloxicam from this device into different release media.

METHODS

Films of cross-linked gelatin matrix containing meloxicam were prepared, hardened for various time periods and cut in a form to fit to the periodontal pocket anatomy. The release of active agents was studied separately in 10 ml distilled water, artificial saliva and pH 7.4 phosphate buffer at 37 degrees C. Apparatus Vibrax was used at 120 r.p.m. Determinations were carried out spectrophotometrically, and the release profiles were plotted as a function of time. The results were evaluated by the similarity test.

RESULTS

The release rates of meloxicam from the hardened (1 h, 4 h, 8 h) formulations were slower than the unhardened formulation in all the three release media. Increasing the hardening time decreased the release rates. The overall release rates were similar in artificial saliva and pH 7.4 phosphate buffer, while it was lower in distilled water.

CONCLUSIONS

As a conclusion, cross-linked gelatin matrix films may be considered as a suitable inert material for obtaining a prolonged local release of meloxicam as an adjunct to the mechanical periodontal treatment. As required, further in vitro and in vivo studies will be performed before starting clinical applications of this controlled-release formulation of the anti-inflammatory agent.

Individual and combined effects of selective cyclooxygenase-2 inhibitor and omega-3 fatty acid on endotoxin-induced periodontitis in rats

BACKGROUND

The present study was planned to evaluate the individual and combined effects of selective cyclooxygenase-2 (COX-2) inhibitor, celecoxib, and omega-3 fatty acid on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), leukotriene B4 (LTB4), and platelet activating factor (PAF) in endotoxin-induced periodontitis in rats.

METHODS

Experimental periodontitis was induced by repeated injection of Escherichia coli endotoxin (LPS). Forty-four adult male Sprague-Dawley rats were divided into five study groups: saline control, LPS, celecoxib, omega-3 fatty acid, and combination celecoxib and omega-3 fatty acid. Celecoxib and omega-3 fatty acid were given either as a single agent or as a combination therapy during 14 days of the study period. At the end of the 2-week protocol, the rats were sacrificed, the gingival tissues were dissected and extracted, and the extracts were analyzed for PGE2, PGF2alpha, and LTB4 levels by enzyme immunoassay and for PAF levels by radioimmunoassay. The defleshed jaws were analyzed morphometrically for alveolar bone loss. Data were evaluated statistically by using parametric tests.

RESULTS

LPS injection resulted in significantly more bone loss than the saline controls (P<0.05) and significant elevations in the gingival tissue levels of all the analyzed mediators except PGF2alpha. Individual administration of celecoxib revealed significant reductions in PGE2 and PAF levels (P <0.05), while omega-3 fatty acid provided significant reduction in PGE2, PGF2alpha, and LTB4 levels compared to the LPS group (P <0.05). Combined administration of celecoxib and omega-3 fatty acid exhibited significantly lower values than those of the LPS group in all the analyzed membrane phospholipid mediators (P <0.05), which approximated the levels in the saline control group (P>0.05).

CONCLUSIONS

The results of the present study indicate that celecoxib and omega-3 fatty acid, when used individually, show a rather partial effect on the control of the analyzed mediators, but when combined they show a synergic effect and provide significant reductions in the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF in LPS-induced experimental periodontitis. These findings may pioneer further clinical human studies investigating the possible place of celecoxib and omega-3 fatty acid in periodontal treatment.

Adjunctive subantimicrobial dose doxycycline: effect on clinical parameters and gingival crevicular fluid transforming growth factor-beta levels in severe, generalized chronic periodontitis

BACKGROUND

At present there is limited data concerning the efficacy of non-surgical periodontal therapy supplemented with subantimicrobial dose doxycycline (SDD) in the treatment of severe, generalized periodontitis. The purpose of the present study was to evaluate the effect of adjunctive SDD therapy on clinical periodontal parameters and gingival crevicular fluid (GCF) transforming growth factor-beta1 (TGF-beta1) levels in patients with severe, generalized chronic periodontitis over a 6-month period.

METHODS

Thirty-five patients with severe, generalized periodontitis and 11 periodontally healthy subjects were included in the present study. Patients received full-mouth supragingival debridment at baseline and randomized to take either SDD b.i.d. or placebo b.i.d. for 3 months. Patients received root planing and oral hygiene instruction once a week for four consecutive weeks. Clinical measurements including probing depth (PD), clinical attachment level, papilla bleeding index and plaque index and GCF sampling were performed at baseline, 3 and 6 months. The GCF TGF-beta1 levels were analysed by enzyme-linked immunosorbent assay.

RESULTS

Thirteen patients in both study groups completed the 6-month trial. Following scaling and root planing (SRP) plus SDD and SRP plus placebo therapy significant improvements in clinical periodontal parameters of both groups were observed (p<0.025). In the SDD group a significantly higher percentage (%73.4) of deep pockets resolved (PD reduction > or =3 mm from baseline) when compared with placebo group (%49.7) at 6 months (p<0.05). At baseline there were no significant differences in GCF TGF-beta1 levels between three groups. Both total amount and concentration of GCF TGF-beta1 in SDD and placebo groups increased when compared with baseline at 3 months. However, only GCF TGF-beta1 levels of SDD group was significantly higher than baseline (p<0.025) and placebo group (p<0.017) at 3 months. At 6 months GCF TGF-beta1 levels of both groups were similar to baseline levels (p<0.025).

CONCLUSIONS

These data indicate that combination of SDD with non-surgical therapy improves clinical parameters of periodontal disease and increases GCF TGF-beta1 levels together with a decrease in prevalence of residual pockets in patients with severe, generalized chronic periodontitis. Increased GCF TGF-beta1 levels following SDD therapy might suggest a novell pleiotrophic mechanism for tetracyclines to inhibit connective tissue breakdown.

Therapeutic versus prophylactic plus therapeutic administration of omega-3 fatty acid on endotoxin-induced periodontitis in rats

BACKGROUND

The aim of the present study was 1) to evaluate the possible effects of therapeutic usage of omega-3 fatty acid on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), platelet activating factor (PAF), and leukotriene B4 (LTB4) in endotoxin-induced periodontitis in rats and 2) to investigate whether prophylactic usage provides any additional benefits to therapeutic doses of omega-3 fatty acid.

METHODS

Experimental periodontitis was induced by repeated injection of Escherichia coli lipopolysaccharide (LPS). Thirty-six adult male Sprague-Dawley rats were divided into four study groups: 1) saline controls; 2) LPS; 3) therapeutic omega-3 fatty acid (TO3); and 4) prophylactic plus therapeutic omega-3 fatty acid (P + TO3) groups. In TO3 group, omega-3 fatty acid was given for 15 days following induction of experimental periodontitis. In P + TO3 group, omega-3 fatty acid was started 15 days before baseline, and then periodontitis was induced at baseline and omega-3 fatty acid was continued for 15 days after baseline. On day 15 after baseline, all rats were anesthetized and sacrificed. PGE2, PGF2alpha, and LTB4 levels in gingival tissue samples were analyzed by enzyme immunoassay and PAF levels were analyzed by radioimmonoassay. Data were evaluated statistically by using parametric tests.

RESULTS

LPS injection resulted in significant amount of bone loss (P<0.05). Neither therapeutic nor prophylactic plus therapeutic administration of omega-3 fatty acid with the doses and duration of therapy used in the present study was effective in preventing endotoxin-induced alveolar bone loss. TO3 group exhibited significant decreases in the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF compared to the LPS group (P<0.05). PGE2 and PGF2alpha levels in TO3 group were similar to those of the saline group (P>0.05), while LTB4 and PAF levels were statistically higher than the saline group (P<0.05). Prophylactic plus therapeutic usage of omega-3 fatty acid provided similar levels of all these mediators to those of the saline controls (P>0.05).

CONCLUSIONS

Therapeutic omega-3 fatty acid significantly reduced the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF in experimental periodontitis. Furthermore, prophylactic usage of omega-3 fatty acid provided additional beneficial effects to the therapeutic administration by decreasing the gingival tissue levels of these mediators to levels of healthy tissue. These findings should be verified by longitudinal clinical trials investigating clinical and biochemical periodontal parameters to better define the possible role of omega-3 fatty acids in periodontal treatment.

Augmented transforming growth factor-beta1 in gingival crevicular fluid of smokers with chronic periodontitis

BACKGROUND

Patients who smoke are at increased risk for chronic periodontitis (CP). Also, CP patients who smoke exhibit significantly less reduction of probing depths and gains in clinical attachment compared to non-smokers following periodontal therapy. Several studies suggest that the effects of smoking on the host response may be paramount in regulating the basal systemic inflammatory status and therapeutic outcomes in this cohort. Growth factors, specifically transforming growth factor beta1 (TGF-beta1), are critical in regulating the wound healing response by controlling cell division, differentiation, and motility. The hypothesis to be tested was that gingival crevicular fluid (GCF) TGF-beta1 production was altered in smokers compared to non-smokers with CP.

METHODS

GCF was collected from smokers and non-smokers with CP, both at baseline and 1 to 2 weeks after initial therapy. GCF volume was determined using an electronic device and TGF-beta1 concentration was measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Smokers exhibited a higher mean concentration of GCF TGF-beta1 at baseline compared to non-smokers (P = 0.03). After initial therapy, smokers exhibited significantly less reduction in mean GCF volume compared to non-smokers (P = 0.04).

CONCLUSIONS

Augmented constitutive production of GCF TGF-beta1 in smokers may explain the clinical appearance of fibrotic gingival tissue exhibited by this patient cohort. A diminished reduction in GCF volume in smokers following root instrumentation suggests a chronic inflammatory status in conjunction with an ineffective host response. These findings support the concept that smokers with CP display an altered local inflammatory response after initial therapy, perhaps symptomatic of colonization by residual periodontal pathogens.

In vitro studies on controlled-release cellulose acetate films for local delivery of chlorhexidine, indomethacin, and meloxicam

BACKGROUND

Delivery of medications into periodontal pockets to suppress or eradicate the pathogenic microbiota or modulate the inflammatory response, thereby limiting periodontal tissue destruction, has attracted significant interest with the purpose of effective periodontal treatment. However, no study has previously attempted to develop a controlled-release formulation of anti-inflammatory agents to be used in the field of periodontology. The aim of the present study was to examine the in vitro release profile of chlorhexidine gluconate, indomethacin, and meloxicam from cellulose acetate films.

METHODS

Cellulose acetate films containing chlorhexidine gluconate, indomethacin, and meloxicam were prepared and cut in a form to fit to the periodontal pocket anatomy. The release of active agents was studied in 10 ml artificial saliva at 37 degrees C. Apparatus Vibrax was used at 150 r.p.m. Determinations were carried out spectrophotometrically and the release profiles were plotted as a function of time.

RESULTS

The formulations showed two different release patterns for a total observation period of approximately 120 h. When the formulations of the three active agents were compared, the release patterns of meloxicam and chlorhexidine gluconate were found to be similar, while the indomethacin-containing formulation exhibited the fastest release rate.

CONCLUSIONS

As a conclusion, cellulose acetate may be a suitable inert material for obtaining a prolonged local release of various anti-inflammatory agents like meloxicam. Further in vitro and in vivo studies are required before starting clinical applications of these controlled-release formulations of anti-inflammatory agents.

The effects of ovulation induction during infertility treatment on gingival inflammation

BACKGROUND

Ovulation induction is the most common method of infertility treatment in which the ovaries are stimulated to produce multiple follicles. The aim of this study was to assess the effects of three drug protocols of ovulation induction: clomiphene citrate (CC) alone, CC combined with follicle stimulating hormone (FSH), and CC combined with human menopausal gonadotropin (HMG) on the gingival tissues of women who were undergoing infertility treatment.

METHODS

Study population was composed of 18 women using CC for three menstrual cycles or less and 16 women using CC for more than three cycles; 21 women using CC-FSH; and 24 women using CC-HMG who had at least four cycles of CC alone the previous year. All subjects were clinically examined for plaque levels (plaque index), gingival inflammation (gingival index), bleeding on probing, and gingival crevicular fluid volume. The results were compared with a control group of 20 women matched for age, educational and professional level, and oral habits and who had never used ovulation drugs.

RESULTS

Despite similar plaque levels (P>0.05), women using CC for more than three cycles and combined protocols of CC-FSH and CC-HMG had higher levels of gingival inflammation (P<0.01, P<0.001 and P<0.001, respectively), bleeding (P<0.001), and GCF volume (P<0.001) when compared to the control group and to the users of CC for three cycles or less.

CONCLUSIONS

The results of this study have shown that ovulation induction, which is the most common method in the management of infertility, exacerbates gingival inflammation, bleeding, and GCF volume and that the duration of the usage of these drugs is strongly associated with the severity of gingival inflammation.