During tooth socket healing, the coagulum in the socket is replaced by fibrous connective tissue which undergoes mineralization and eventually becomes bone. Using this model, the healing process of the tooth socket and the role of type I collagen(CI), fibronectin(FN), bone sialoprotein(BSP), and osteopontin(OP) in the process were studied. Thirty Sprague-Dawley rats weighing 130-150gm were fed fi -aminopropionitcille for 5days before extraction of the first maxillary molars, and sacrified by perfusion with 4% paraformaldehyde at 1, 3, 5, 7, and 10days after tooth extraction.
The socket and surrounding tissues were cut, demineralized, dehydrated and embedded in paraffin.
For morphological observation, the sections were stained by Azan. Immunostaining of the ECM components was achieved by the avidin-biotin complex method.
The results as follows;
1. Morphology of the tooth socket 1day after tooth extraction. The socket was filled with blood coagulum which was composed of densly aggregated red blood cells, platelets and fibrin network.
2. Morphology of the tooth socket 3days after tooth exyraction. A large portion of the coagulum was replaced by
fibrous connective tissue contains a large number of fibroblasts, come from periphery of the socket.
3. At 5days, the newly formed bone demonstrated the highest proliferation activity. At 7days, the soclet was occupied
with new bone.
4. Type I collagen was observed in the newly formed connective tissue and around the new bone. fiber.
5. Intensive staining for fibronectin was observed in granulation tissue, especially around blood vessels as well as inflammatory cells.
6. Strong immunostaining for bone sialoprotein and osteopontin was found in osteoblasts and new bone, while weaker staining was observed on dense connective tissue.
7. These data suggest that collagen and noncollagen proteins (FN, BSP, OP) an important role daring socket healing.
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