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Matrix metalloproteinase-8 (MMP-8) in pulpal and periapical inflammation and periapical root-canal exudates
J Wahlgren1, T Salo, O Teronen
1Faculty of Medicine and Biomedicum, Oral Pathology Unit/Laboratory Diagnostics, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland.
Aim:
To study the presence, levels and molecular forms of matrix metalloproteinase (MMP) -8 (collage-nase-2) in pulpal and periapical inflammation, and the changes in MMP-8 levels in root-canal exudates during root-canal treatment.
Methodology:
Periapical exudate samples were collected from 11 necrotic teeth with radiographically verified periapical periodontitis during three root-canal treatment visits with interappointment calcium hydroxide (Ca(OH)2) medication. MMP-8 levels and molecular forms were analyzed with immunofluorescent assay (IFMA) and Western immunoblot. Inflamed pulp tissue and periapical granuloma tissue (n = 10 for both) were obtained from other patients and used for MMP-8 immunohistochemical (IHC) staining.
Results:
The periapical exudate samples demonstrated marked differences in MMP-8 levels between the teeth in the first visit and significant decrease in MMP-8 levels during the root-canal treatment (P = 0.0107). One specimen failed to show a decrease in MMP-8 below 1000 ng mL(-1) a vertical root fracture was later diagnosed and the tooth extracted. IHC staining showed that in addition to PMN-leucocytes, macrophages and plasma cells produced MMP-8 in pulp and periapical granulomas.
Conclusions:
The findings demonstrate the presence of MMP-8 in the inflamed pulp and periapical tissue, indicating that MMP-8 has a role in pulpal and periapical inflammation, most likely participating in tissue extracellular matrix degradation. They further indicate that MMP analysis from periapical exudate could be used to indicate and monitor inflammatory activity and the success of treatment in teeth with periapical lesions.
Insights
Matrix metalloproteinase-8 (MMP-8) is present in inflamed dental tissues and its levels decrease during root canal treatment. MMP-8 analysis in exudates can monitor inflammation and treatment success in periapical lesions.
Area of Science:
- Endodontics
- Oral Pathology
- Biochemistry
Background:
- Pulpal and periapical inflammation involve complex molecular processes.
- Matrix metalloproteinases (MMPs), particularly MMP-8 (collagenase-2), are implicated in tissue degradation.
- Understanding MMP-8's role is crucial for managing endodontic infections.
Purpose of the Study:
- To investigate the presence, levels, and molecular forms of MMP-8 in pulpal and periapical inflammation.
- To assess changes in MMP-8 levels in root canal exudates during treatment.
Main Methods:
- Samples of periapical exudate were collected from 11 teeth with periapical periodontitis during root canal treatment.
- MMP-8 levels and forms were analyzed using immunofluorescent assay (IFMA) and Western immunoblot.
- Immunohistochemical (IHC) staining was performed on inflamed pulp and periapical granuloma tissues.
Main Results:
- MMP-8 levels in periapical exudates varied significantly between initial visits and decreased during root canal treatment (P=0.0107).
- One case with persistent high MMP-8 levels was associated with a diagnosed vertical root fracture.
- IHC revealed MMP-8 production by PMN-leukocytes, macrophages, and plasma cells in inflamed dental tissues.
Conclusions:
- MMP-8 is present in inflamed pulp and periapical tissues, contributing to extracellular matrix degradation.
- MMP-8 analysis in periapical exudates can serve as an indicator of inflammatory activity.
- Monitoring MMP-8 levels may help assess the success of root canal treatment for periapical lesions.
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