What defines the thin layer of bone lining the socket around the tooth root?

The thin layer of bone lining the socket around the tooth root is known as alveolar bone proper. This bone is critical for anchoring teeth in the alveolar process and forms the inner aspects of the tooth socket, or alveolus. It is directly involved in the process of tooth support and has a unique structural characteristic where it contains many perforations that allow for the passage of blood vessels and nerves into the periodontal ligament and surrounding tissues.

In contrast, cortical bone refers to the dense outer layer of bone that provides strength and protection but does not line the socket itself. Spongy bone, also known as cancellous bone, is found within the interior of the alveolar bone but does not specifically define the socket lining. Lastly, periapical bone refers to the bone surrounding the apex of the tooth root and is not synonymous with the thin layer of bone that directly interfaces with the root of the tooth within the socket.