Figure 49. Dimensional ridge alternation : 8 weeks
At 8 weeks after tooth extraction, the entrance to the extraction site is bridged with cortical bone. The woven bone in the socket is replaced with bone marrow and some trabeculae of lamellar bone. At the crests of the buccal and lingual cortical plates, there are signs of ongoing bone resorption.
Figure 36. Day 60 - 180 : Initial periosteum formation
After 60 to 90 days, newly formed woven bone forms a bridge across the entrance of the socket. The epithelium covering the bone is keratinized. Soft tissue healing at this stage has been completed. At 90 to 180 days after tooth extraction, the woven bone is gradually remodeled into cortical bone. A periosteum is established with collagen ...
Figure 29. Day 180 : large marrow spaces
After 180 days of healing, beneath the marginal cortical bone at the entrance of the socket as denoted by the arrow, most of the socket is filled with trabecular bone that includes large marrow spaces. The bone is characterized by a limited number of trabeculae of lamellar bone. The bone marrow contains large numbers of adipocytes but only a few inflam...
Figure 28. Day 120 : cortical bone & trabecular bone
At 120 days of healing, the entrance of the socket, denoted with an arrow, has become reinforced by layers of cortical bone that are deposited over the previously formed woven bone.
Figure 18. Extraction socket wall
The buccal bone plate is usually thin, less than 1 mm, especially in the anterior dentition, and it consists mainly of bundle bone. On the contrary, the lingual or palatal wall of the socket is usually thicker than its buccal counterpart, and some trabecular bone may be present.