Distributions of fibronection (Fn) in wounds produced by teeth extractions in Wistar rats were examined by immunoperoxidase labelling for Fn and the following findings were observed.
1) Fn was found in the whole socket at 24 hours after tooth extraction.
2) At 2-7 days after tooth extraction, Fn gradually disappeared from the outside of the socket which was replaced by fibrous tissue. In these sections, the fibroblasts invaded the central site of the socket where Fn was found.
3) At 14 days after tooth extraction, Fn completely disappeared from the whole socket. In this section, an active new bone formation from the adjacent bone was found.
Furthermore, we investigated the time course of rat plasma Fn level after tooth extraction. It was found that the plasma Fn level increased during the first 24 hours after tooth extraction, followed by a gradual decline from 48 hours to 7 days post-treatment.
These findings suggest that Fn could be a useful factor in the early phase of wound healing after tooth extraction.
