Utility of a haemoglobin test of gingival crevicular fluid: A multicentre, observational study.

OBJECTIVE: The purpose of this study was to verify the accuracy and utility of clinical parameters (plaque index, gingival crevicular fluid volume, probing depth, clinical attachment level, bleeding on probing and gingival index) and biochemical parameters (aspartate aminotransferase, protein and haemoglobin) in a longitudinal analysis during the supportive periodontal therapy period. SUBJECTS AND METHODS: A total of 279 test sites of 128 patients were investigated clinically and biochemically. After the first examination of clinical and biochemical parameters, periodontal support treatments were administered immediately and performed once every three months up to the second examination. RESULTS: All of the clinical and biochemical parameters were significantly lower at the second examination than at the first, except for the plaque index and bleeding on probing. Of these parameters, in particular, aspartate aminotransferase and haemoglobin in the gingival crevicular fluid were significantly reduced compared to those of the first examination in both the ≤4 and ≥5 mm probing depth groups, and they clearly suggested that periodontitis tended to recover. CONCLUSION: Adding the haemoglobin test to the bleeding on probing test strongly improves the accuracy of measurement of clinical parameters after periodontal treatment.

Effect of cellular communication network factor 2/connective tissue growth factor on tube formation by endothelial cells derived from human periodontal ligaments.

OBJECTIVES: To clarify the role of cellular communication network factor 2/connective tissue growth factor (CCN2/CTGF) in periodontal tissue regeneration by investigating, the proliferative and tubulogenic responses of human endothelial cells obtained from the periodontal ligament to CCN2/CTGF. DESIGN: Endothelial cells were seeded on agar gel medium with or without 50 ng/mL recombinant CCN2/CTGF (rCCN2/CTGF) and cultured for 6 h. Cells were morphologically and phenotypically analyzed by immunofluorescent microscopy. A colorimetric assay was used to evaluate cell proliferation, and transmission electron microscopy (TEM) was used for ultrastructural analysis. RESULTS: The proliferation of endothelial cells was best promoted by rCCN2/CTGF at 50 ng/mL. In the control group, tube formation was not observed within 6 h. In contrast, endothelial cells seeded on the agar with 50 ng/mL rCCN2/CTGF clearly showed proliferation with network formation. Under a two-dimensional culture condition, a dense network of endothelial cells was not constructed on the plastic bottom. However, drastic morphological change was observed in the endothelial cells on the agar containing rCCN2/CTGF. The endothelial cells in the dense network were interconnected with each other and showed a tube-like structure. Tight junctions or adherens junctions were observed between the adjoining endothelial cells in the dense network. CONCLUSIONS: CCN2/CTGF was found to promote the proliferation and tubulogenesis of endothelial cells from the periodontal ligament. These results suggest that CCN2/CTGF may contribute to the regeneration of damaged periodontal tissue by activating the remaining endothelial cells.

Chronological Gene Expression of Human Gingival Fibroblasts with Low Reactive Level Laser (LLL) Irradiation.

Though previously studies have reported that Low reactive Level Laser Therapy (LLLT) promotes wound healing, molecular level evidence was uncleared. The purpose of this study is to examine the temporal molecular processes of human immortalized gingival fibroblasts (HGF) by LLLT by the comprehensive analysis of gene expression. HGF was seeded, cultured for 24 h, and then irradiated with a Nd: YAG laser at 0.5 W for 30 s. After that, gene differential expression analysis and functional analysis were performed with DNA microarray at 1, 3, 6 and 12 h after the irradiation. The number of genes with up- and downregulated differentially expression genes (DEGs) compared to the nonirradiated group was large at 6 and 12 h after the irradiation. From the functional analysis results of DEGs, Biological Process (BP) based Gene Ontology (GO), BP 'the defense response' is considered to be an important process with DAVID. Additionally, the results of PPI analysis of DEGs involved in the defense response with STRING, we found that the upregulated DEGs such as CXCL8 and NFKB1, and the downregulated DEGs such as NFKBIA and STAT1 were correlated with multiple genes. We estimate that these genes are key genes on the defense response after LLLT.

Clinical and microbiological effect of frequent subgingival air polishing on periodontal conditions: a split-mouth randomized controlled trial.

The objective of this study was to evaluate the clinical effects of repeated subgingival debridement by air polishing during supportive periodontal therapy. A double-blind, randomized controlled trial of 6 months in duration was conducted on 19 recall patients who were previously treated for chronic periodontitis. Three sites with probing pocket depths (PPD) of 4-9 mm in each of the patients were randomly assigned to the following treatments: Glycine powder/air polishing every 30 days (group 1), glycine powder/air polishing at baseline and on day 90 (group 2), or water irrigation every 30 days (group 3). Clinical parameters were recorded and microbiological sampling was performed at 0, 90, and 180 days post-treatment. Subgingival samples were analyzed using real-time PCR methods for Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Between baseline and 90 days, group 1 showed significantly more PPD reduction compared to group 3 and no significant differences with group 2. Between baseline and 180 days, group 1 displayed a significant increase in clinical attachment level compared with group 3. No differences were observed among the groups in numbers of total bacteria or percentage of investigated bacteria at any time point. This study revealed that routine subgingival air polishing at 30-day intervals had significant clinical effects in moderately deep pockets in patients who underwent supportive periodontal therapy.

Correlation Between Gingival Crevicular Fluid Hemoglobin Content and Periodontal Clinical Parameters.

BACKGROUND: Probing depth (PD) and bleeding on probing (BOP) are essential clinical parameters used for periodontal diagnosis. This study investigated whether detection of hemoglobin (Hb) in gingival crevicular fluid (GCF), along with PD and BOP, would improve diagnostic accuracy. METHODS: After plaque index (PI) was measured, GCF was collected from the gingival sulci of 401 anterior teeth in the maxilla and mandible from 184 patients who had entered periodontal maintenance therapy. Clinical parameters (gingival index [GI], PD, clinical attachment level [CAL], and BOP) were recorded. Hb values in GCF were assessed by immunochromatography. Moreover, cutoff values for PI, GI, and CAL based on the degree of PD and amount of GCF were created and analyzed. RESULTS: Hb was detected in 64.8% of GCF samples in 105 BOP-negative (-) sites in the periodontally stable group out of 107 sites that were less than all cutoff values. There were 71 BOP(-) sites in the periodontal-management-required group out of 122 sites that were more than all cutoff values, although no improvement in periodontal disease was observed. Hb was detected in 88.7% of GCF samples from these 71 BOP(-) sites. CONCLUSIONS: Hb was observed in more than 60% of GCF samples in BOP(-) gingival sulci in both periodontally stable and periodontal-management-required groups. These results suggest inspection of Hb derived from microbleeding in gingival sulci may serve as an index for preclinical diagnosis.

Matrix remodeling response of human periodontal tissue cells toward fibrosis upon nicotine exposure.

It is widely accepted that fibrosis is frequently observed in the gingiva of smokers. However, the mechanisms by which smoking results in pathological changes in periodontal tissue that lead to fibrosis are not entirely clear. Our former report showed that type I collagen synthesis was promoted by nicotine via CCN family protein 2 in human periodontal tissue cells. Here, we evaluated other aspects of nicotine function from a viewpoint of extracellular matrix (ECM) remodeling. Human gingival fibroblasts (n = 4) and periodontal ligament cells (n = 3) were isolated. The cells were treated with nicotine at a variety of concentrations for 12-48 h. Modulators of matrix remodeling were measured using enzyme-linked immunosorbent assays. Cell migration and morphology were also evaluated. As a result, following treatment with 1 µg/ml nicotine, tissue inhibitor of metalloproteinase-1 and transforming growth factor-ß1 production in both cell lysates and supernatants, and matrix metalloproteinases-1 production in cell lysates, were significantly increased (p < 0.05). Compared to controls, cell migration was significantly inhibited (p < 0.005) by nicotine in a time-dependent manner. Electron microscopic analysis revealed the presence of a number of vacuoles in nicotine-treated cells. These results indicate that nicotine not only impairs fibroblast motility, and induces cellular degenerative changes, but also alters ECM-remodeling systems of periodontal cells. Induction of matrix remodeling molecules, combined with type I collagen accumulation, may account for the molecular mechanism of nicotine-induced periodontal fibrosis.

Evaluation of bleeding on probing and gingival crevicular fluid enzyme activity for detection of periodontally active sites during supportive periodontal therapy.

This study aimed to analyze the enzyme activity in gingival crevicular fluid (GCF) and its association with clinical parameters, especially bleeding on probing (BOP), and thus reconsider the significance and accuracy of recording BOP. A total of 184 patients who had entered supportive periodontal therapy were selected and GCF was collected from 401 sites before recording the clinical parameters, probing pocket depth (PPD), BOP, clinical attachment level, gingival index and plaque index. The enzyme activity of neutrophil elastase and aspartate aminotransferase and amount of protein in GCF were also analyzed. In the clinical parameters for biochemical data, amount of GCF showed the most correlation. A cut-off value for BOP and PPD were determined by the ROC curve and Youden index. Analysis was performed with all clinical parameters and biochemical data. Of the 401 sites, 51 were less than the cut-off value and were BOP-negative. On the other hand, 29 sites had values more than the cut-off value, with 14 BOP-negative sites and 15 BOP-positive sites. A conclusion is as follows: twenty-nine sites with values more than the cut-off value were diagnosed as sites requiring periodontal management, however, 14 of these were BOP-negative. These results suggest that combining other biochemical tests with examination of BOP and PPD may improve the validity of periodontal disease diagnosis. In future studies, it will be essential to find a marker that can precisely detect periodontal disease activity, and to develop a diagnostic tool for chair-side use.