Expression Of MMP-9 In Human Gingival Fibroblasts, Rat Osteoblasts And Peri-implant Sulcular Fluid

Current clinical diagnosis of anormales as well as the clinical evaluation of dental implants predominantly resorts to methods and practices of procedures commonly used in periodontics. It is the imperative precondition of an effective clinical therapy of implantitis to fully understand the mechanisms and the progression of extra cellular matrix degradation during the course of periodontal disease development.Dental implants are fixed into alveolar bone by surgery. The cells of the interfacing tissue with implants are mostly osteoblasts and fibroblasts.In our study, we used the proinflammatory cytokine Interleukin-1β to stimulate healthy human gingival fibroblasts and rat osteoblasts in vitro. We studied the effects and mechanisms of two cell types, by means of evaluating the expression of MMP-9 in the cells, using Interleukin-1β as stimulating proinflammatory agent.As the periodontal tissue of implant and natural tooth are different, our study also included comparative evaluations of MMP-9 levels in PISF and GCF. Mainreason for this research was: a. to study potential differences of matrix destruction in peri-implantitis versus periodontitis; b. to understand the effect of MMP-9 on peri-implantitis; and c. to eventually offer new and/or advanced possibilities for the therapeutic measures of peri-implantitis.Human gingival fibroblasts (HGF) were cultured in gingival tissue under standard conditions. The third generation cells were selected for phenotypical identification of fibroblast and the experiments were subsequently conducted. The methods and means used for the fibroblast identifications were a. cell shape evaluation with an electron microscope, b. vimentin presence using immunoh-istochemistry (IC), and c. cytokeratin presence using immunohisto-chemistry (IC).Rat osteoblasts were isolated by means of continuous enzymatic digestion. Cells were purified by marginal adhesion method. The cell culture was carried out under standard conditions. The third generation cells were selected for phehotypical identification of osteoblast and the experiments were subsequently conducted. The methods and means used for the osteoblast identifications were a. cell shape evaluation with an electron microscope, b. ALPase stain, and c. mineralization experiments.Our studies delivered the following results: typically, fibroblast cells spread on the surface of the glass coverslips. The IC identifacation of vimentin in the test specimen was positive, IC identifacation of cytokeratin, however, was negative. Osteoblast typically spreads on the surface of glass coverslips. Both, ALPase stain and mineralization stain identification was positive. Cells used in this project proved to be monotype with the typical phenotype of fibroblasts and osteoblasts. Their typical features and functions as fibroblasts and osteoblasts were confirmedby these experiments.For the control group, cells were cultured in different Interleukin-lp concentrations. ISH and IC were conducted to examine the MMP-9 levels of mRNA and protein. The surfaces of fibroblast and osteoblast cells were observed by means of Scanning Electron Microscopy (SEM).Results: Dosed-dependently, IL-ip induced MMP-9 mRNA expression and protein synthesis in the cells. Shape and surface of cells changed at an IL-ip concentration of 1.0 ng/ml. Both, fibroblasts and osteoblasts, showed active functions of synthesis and secretion of protein at an IL-ip concentration of 1.0 ng/ml.These studies focused on the MMP-9 levels in PISF and GCF. A periodontal probe was used to determine actual pocket depths. Each was visually examined including buccal/labial site, lingual/palatal, distal site and mesial site. After PISF or GCF collection, the paper strip was transferred to a Periotron 8000 for a quantification of the fluid volume. MMP-9 quantification was assessed by means of sandwich ELIS A.Result: PISF of healthy group expressed MMP-9; Peri-implantitis specimen had significantly higher levels of MMP-9 than the healthy group specimen (PO.05); the level of MMP-9 in peri-implantitis was not higher than that in-periodontitis. (P>0.05); the levels of MMP-9 in peri-implantitis were positively and significantly associated with the clinical indices.Fibroblasts and osteoblasts are among the cells implicated in destructive processes of peri-implantitis and periodontitis. MMP-9, expressed by local cell such as fibroblasts and osteoblasts, apparently plays an important role in thegingival extra-cellular matrix degradation during peri-implantitis and periodontitis progression. The higher and easily confirmed expression of MMP-9 in peri-implantitis might be a useful biochemical indication to monitor per-implant health and/or disease. MMP-9 levels in PISF or GCF, determined by ELISA methode, appear to be a sentitive and reliable diagnostic indicator of the state of progression of peri-implantitis and periodontitis.