Expression of matrix metalloproteinase-2 in the extracellular matrix of osseointegrated and diseased implants

Abstract

Background: Recently with improvement of dental implantology science, osseointegrated implants show aconsiderable durability, however; failures are not completely avoidable. Matrix metalloproteinase-2 (MMP-2)expression is disturbed in many pathological conditions such as peri-implantitis and periodontitis. This study wascarried out to investigate the tissue expression of MMP-2 in the extracellular matrix of osseointegrated and diseasedimplants.Subjects and methods: Gingival biopsies were collected from six patients having osseointegrated or workingimplants and twenty with diseased or non osseointegrated implants and (6) controls having no implants. In situhybridization technique was used to analyze the changes in immunoreactivity of ECM-controlling MMP-2.Results: The findings of the present study indicate that the expression of MMP2 was significantly elevated in failedimplants versus healthy implants (P<0.01). In addition, MMP-2 was detected in peri-implant sites with ongoing boneloss, cavitations and inflammatory reaction.Conclusion: The in situ hybridization technique, showed clear evidence that MMP-2, which is involved in the processof osseointegration and bone remodeling, increase greatly in the presence of bone destruction, cavitations, severeinflammation and fibrous tissue formation. The data link titanium- induced bone remodeling to changes in expressionand distribution of MMP-2.