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Updated: Jun 21, 2026
The Establishment of a Murine Mandibular Molar Extraction Socket Healing Model
Published on: January 13, 2023
Healing of extraction sockets in collagenase-2 (matrix metalloproteinase-8)-deficient mice
Jarkko T Korpi1, Pirjo Aström, Niko Lehtonen
1Department of Oral and Maxillofacial Surgery, Institute of Dentistry, University of Oulu and Oulu University Hospital, Oulu, Finland.
Abstract:
Matrix metalloproteinase-8 (MMP-8) participates in skin wound healing and inflammation. We hypothesized that MMP-8 plays a role in wound healing after tooth extraction and in periapical inflammation. Bone formation, collagen metabolism, and inflammation in tooth extraction socket and in periapical lesions were analyzed in wild-type mice and in MMP-8-deficient (MMP-8(-/-)) mice. New trabecular bone area in the extraction sockets and in periapical lesions were similar in both groups. In extraction sockets significantly more type III procollagen was synthesized, and the neutrophil and MMP-9 levels were lower in MMP-8(-/-) mice. The amount of Fas ligand, identified as a substrate for MMP-8, was lower in alveolar mucosa but higher in alveolar bone of MMP-8(-/-) mice. These results indicate that MMP-8 can modulate inflammation and collagen metabolism of alveolar bone and mucosa.
Insights
Matrix metalloproteinase-8 (MMP-8) influences wound healing and inflammation. MMP-8 deficiency impacted collagen synthesis and inflammatory markers in mice after tooth extraction, suggesting a role in alveolar bone and mucosa healing.
Area of Science:
- Oral biology
- Wound healing research
- Inflammation studies
Background:
- Matrix metalloproteinase-8 (MMP-8) is involved in skin wound healing and inflammation.
- Its role in tooth extraction socket healing and periapical inflammation is not well understood.
Purpose of the Study:
- To investigate the role of MMP-8 in bone formation, collagen metabolism, and inflammation following tooth extraction.
- To analyze the impact of MMP-8 deficiency on healing processes in extraction sockets and periapical lesions.
Main Methods:
- Comparison of wild-type and MMP-8-deficient (MMP-8(-/-)) mice.
- Analysis of bone formation, collagen metabolism (type III procollagen), neutrophil infiltration, MMP-9 levels, and Fas ligand expression.
- Evaluation in tooth extraction sockets and periapical lesions.
Main Results:
- Bone formation was similar in both wild-type and MMP-8(-/-) mice.
- MMP-8(-/-) mice showed increased type III procollagen synthesis in extraction sockets.
- Neutrophil and MMP-9 levels were reduced in MMP-8(-/-) mice, with altered Fas ligand distribution.
Conclusions:
- MMP-8 plays a role in modulating collagen metabolism and inflammation in the alveolar bone and mucosa after tooth extraction.
- MMP-8 deficiency leads to altered inflammatory responses and collagen synthesis during oral wound healing.
